Effectiveness of a Cognitive Based Intervention on Semantic Memory and Word Retrieval
Info: 17913 words (72 pages) Dissertation
Published: 9th Dec 2019
Project Title: The effectiveness of a cognitive based intervention on semantic memory and word retrieval operations in adult’s aged 60 years and over with Mild non-clinical Cognitive Impairment (MCI).
Table of Contents
Acknowledgments 2
Table of Contents 3
Abstract 5
Introduction 6
CHAPTER 1: Literature Review 7
- History of Terminology 7
- Classification Criteria 7
- MCI Subtypes 8
- Diagnostic Tools: Rating Scales 9
- Etiology and Risk Factors 10
- Conclusion 11
CHAPTER 2: Methodology 12
2.1 Literature Review Resources 12
2.2 Aims of Research 12
2.3 Recruitment Method 12
2.4 Inclusion/ Exclusion Criteria 13
2.5 Experimental Design, Sample Size and Gender 14
2.6 Overview 14
2.7 Procedure 14
2.8 Hypothesis 15
2.9 Ethics 15
CHAPTER 3: Analysis of Results 17
3.1 Table 1:Gender 17
3.2 Table 2:Age 17
3.3 Table 3:Reaction Times to Word TypesPre and Post Intervention 18
3.4 Table 4:Number of Positive Ranks, Negative Ranks and Ties 20
3.5 Table 5:Z scores and Significance 21
CHAPTER 4: Discussion 23
4.1 Aims 23
4.2 Literature 23
4.3 Strengths and Limitations 25
CHAPTER 5: Conclusion 27
5.1 Summary 27
5.2 Future Recommendations 27
References 29
Appendices
Appendix A: Global Deterioration Scale (GDS) 32
Appendix B: Workbook 33
Appendix C: Ethics Approval Form 44
- Informed Consent Letter 51
- Debriefing Letter 54
Abstract
The aim of this dissertation was to test the effectiveness of a cognitive based intervention on semantic memory and word retrieval operations in adults aged 60 years and over with Mild non-clinical Cognitive Impairment (MCI). This dissertation sought to find out if this type of intervention could be used to slow down the progression of Alzheimer’s Disease (AD) in those who have Mild Cognitive Impairment (MCI). Meyer and Schvaneveldt’s (1971) lexical decision paradigm was used to examine the internal workings of the mental lexicon, where semantics and vocabulary are stored. The experiment recorded response rate times and error rates to word and nonword pairs which were displayed on a computer screen. All the data was stored on a software known as SuperLab5 and the results were analysed using SPSS. A total number of 12 participants, both male and female took part in a repeated measures experimental design. In between the repeated measures design, participants were required to take part in a cognitive based intervention in the form of a workbook containing crosswords, for 1 hour per day. Two weeks later the same participants were re-tested using the same lexical decision paradigm. The results showed that there was a slowing of reaction times following the cognitive based intervention. This shows this type of intervention was not successful in enhancing semantic memory and word retrieval operations within this group of 12 participants. Therefore, this type of intervention would not be the best suited method at slowing down the progression of Alzheimer’s Disease (AD) in those who have MCI.
Introduction
In the field of psychology and ageing, a current topic of interest surrounds the normal ageing process and the onset/early onset of Alzheimer’s Disease (AD). Researchers have placed much of the main focus on detecting Alzheimer’s Disease (AD) at its earliest stages in order to prevent or slow down the progression. This has led to the identification of a transitional stage between the cognitive changes associated with normal ageing and the cognitive decline which leads to Dementia. This stage has been termed as the brain disease Mild Cognitive Impairment (MCI), which is said to have an effect on a variety of cognitive domains, but in particular memory. Although Mild Cognitive Impairment (MCI) shares similar characteristics with Alzheimer’s Disease (AD), it does not meet the criteria set for clinically probable Dementia. Therefore, the best non-clinical way to slow down the progression is to keep mentally or socially stimulated whilst clinical trials are underway (Petersen, 2004).
This dissertation aims to test the effectiveness of a cognitive based intervention on semantic memory and word retrieval operations in adults aged 60 years and over with Mild non-clinical Cognitive Impairment (MCI). It also aims to see if this type of intervention is the best suited method at slowing down the progression of Alzheimer’s Disease (AD) in those who have Mild Cognitive Impairment (MCI).
Chapter 1 of this dissertation will review the current literature which relates to this topic and Chapter 2 will discuss the methods used to gather data for this research. Chapter 3 will provide an analysis of the results and Chapter 4 will compare the results against previous literature and will provide an overall evaluation of the research study. Chapter 5 will then conclude this research and will suggest recommendations for future research.
CHAPTER 1:
Review of Literature
This review of literature will examine the previous research which relates to this topic, giving an evaluation and summary of each piece.
As previously mentioned, for many years, researchers have been studying the “gap” between the normal ageing process and the onset/early onset of Alzheimer’s Disease (AD). This “gap” has since become known as the intermediate stage, Mild Cognitive Impairment (MCI). The discovery of this intermediate stage is a relatively new topic which requires further research into certain areas. Some of these areas include: an agreed upon diagnostic criteria, the causes and the treatments. Without an agreed upon diagnostic criteria, it is difficult for researchers and rating scales to clarify what is categorised as Mild Cognitive Impairment (MCI) and without the known causes, it is difficult to create clinical treatments which will help alleviate symptoms or slow down the progression for those suffering from the disease. Therefore, since there is uncertainty over the causes and no clinical trials have yet been approved, the best suited method to slow down the progression is thought to be through the use of a cognitive based intervention (Petersen, 2004).
1.1 History of Terminology
Historically, several terms have been used to describe the intermediate stage which is now known as Mild Cognitive Impairment (MCI). In 1986, The National Institute of Mental Health (NIMH) categorised deficits in memory as Age-Associated Memory Impairment (AAMI). This term was used to describe memory changes during the ageing process which were thought to be a part of normal cognition. This proved to be difficult with widespread application as the term was associated with older adult’s performance rather than the performance of younger people. This led to the re-categorisation of the term, naming it Age Associated Cognitive Decline (AACD). This time the term recognised that other cognitive domains besides memory could be affected during the normal ageing process. In more recent years, The Canadian Study of Health and Ageing defined the term as “Cognitive Decline, No Dementia” (CIND) which refers to an intermediate stage which is not severe enough to be classed as a form of Dementia. The term itself is diverse in nature in regards to cognitive dysfunction and is therefore the closest term associated with Mild Cognitive Impairment (MCI). After gaining more knowledge about the disease, Mild Cognitive Impairment (MCI) is now recognised as a brain disease which is not associated with the normal ageing process (Petersen, 2004).
1.2 Classification of MCI
Mild Cognitive Impairment (MCI) is a brain disease which involves impairment in both memory and non-memory cognitive domains. This is in contrast to the previous criteria set whereby only a memory impairment was required for a diagnosis (Roberts & Knopman, 2013). Petersen (2004) has argued that there is no set or agreed upon diagnostic criteria however, Roberts and Knopman (2013) have suggested that individuals with Mild Cognitive Impairment (MCI) share similar characteristics in the form of a cognitive decline but are essentially able to function normally during daily activities. Therefore, these people cannot be classed as demented. Albert et al (2011, as cited in Huckans, 2013) along with other researchers has refuted this idea by suggesting, like Dementia, individuals with Mild Cognitive Impairment (MCI) experience changes in daily functioning as well as quality of life. The claims from Roberts and Knopman (2013) and Albert et al (2011, as cited in Huckans, 2013) may be accurate but are heavily dependent on where a person lies on the spectrum between normal ageing and Alzheimer’s Disease (AD).
The spectrum between normal ageing and Alzheimer’s Disease (AD) is extensive and therefore the level of cognitive and functional impairment has an impact on the varied outcomes of the disease. These diverse outcomes can be seen in the MCI subtypes (Roberts & Knopman, 2013).
1.3 MCI Subtypes
There are several types of Mild Cognitive Impairment (MCI) with the two most common forms being the Amnestic MCI (aMCI) and the Non-Amnestic MCI (naMCI). Both subtypes differ symptoms-wise but are both said to have an impact on the progression to Alzheimer’s Disease (AD). The aMCI subtype affects a single cognitive domain such as memory whereas the naMCI subtype affects one or more cognitive domains such as language, attention and visual spatial skills (Roberts & Knopman, 2013). The number of cognitive domains affected is also said to have an impact on the underlying brain disease, the severity of the disease and the progression of MCI to Alzheimer’s Disease (AD). The multi-cognitive domain subtype (naMCI) is thought to be more severe than the single cognitive domain subtype (aMCI) as the progression rate from MCI to Alzheimer’s Disease (AD) is higher (Roberts & Knopman, 2013). This was shown in a Cardiovascular Health Study which found individuals with the aMCI subtype progressed to Alzheimer’s Disease (AD) at 6 % per year while those with the naMCI subtype progressed at 16% per year (Petersen, 2004). However, when the aMCI subtype was compared against healthy individuals, those with the aMCI subtype progressed to Alzheimer’s Disease (AD) at 10-15% per year whereas the healthy individuals progressed at 1-2% per year (Petersen et al, 2001). These findings suggest that although one subtype is more likely to progress onto Alzheimer’s Disease (AD), both subtypes can lead onto Alzheimer’s Disease (AD) but at different rates of progression. Even though there is an increased risk of developing Alzheimer’s Disease (AD) no single cause or outcome of the disorder has been identified. Individuals with MCI may remain stable for years, progress onto Alzheimer’s Disease (AD) or another type of Dementia or indeed improve over time (Mayo Clinic, 2016). Due to the diverse nature, there is no fixed outcome to the disease.
1.4 Diagnostic Tools: Rating Scales
There are several useful rating scales which can be used to diagnose individuals with Mild Cognitive Impairment (MCI). The Global Deterioration Scale (GDS) was first introduced by Reisberg et al (1983) who created a rating scale to score impairment on a gradation of 1 to 7. According to Reisberg et al (1983) the scale describes the continuum from normal (1) to the more severe stages of Dementia (4-7). Individuals who score either a 2 or a 3 on the GDS are thought to have Mild Cognitive Impairment (MCI). The Global Deterioration Scale (GDS) has faced many criticisms regarding the conceptual and methodological concepts. Eisdorfer et al (1992) states the Global Deterioration Scale (GDS) was created on the basis of conscious observation of the symptoms found in people with Alzheimer’s Disease (AD) and Age-Associated Memory Impairment (AAMI). There has been no evidence over a discussion of the psychometric methods used which currently relate to the seven stages and the parameters specified on the scale. Overall, The GDS is based on assumptions about independencies between cognitive, functional and behavioural impairment. When the GDS is compared against other rating scales such as the Clinical Dementia Rating Scale (CDR) the two scales rate impairment differently. The Clinical Dementia Rating Scale (CDR) rates impairment on a scale of 0-3, with 0 being normal and 3 being the more severe stages of Dementia. Individuals who score a 0.5 or 1 on the scale are thought to have very mild Dementia or in other terms Mild Cognitive Impairment (MCI). Problems arise when trying to convert the scores from the GDS to the CDR and vice versa as there are no set rules between conversions (Choi, 2003). However, when a semi-structured interview was conducted on 78 individuals with Dementia and 36 controls, regression analysis showed a curvilinear relationship between the GDS and CDR (Choi, 2003). This may provide a way for researchers to interchange the scores between the two scales. Although, the use of a semi-structured interview requires the interpretations and conclusions to be drawn from the researcher’s own personal ability. The interpretations and conclusions drawn may be subjective and therefore inaccurate (Gubrium & Holstein, 2002). This may mean the conversions between the two are invalid and incorrect. Despite these limitations, the GDS and CDR are still regarded as useful tools to diagnose Mild Cognitive Impairment (MCI).
1.5 Etiology (Causes) and Risk Factors
As mentioned previously, the causes of Mild Cognitive Impairment (MCI) are not completely understood. It is thought that in some cases, the causes are linked to brain changes which occur in the initial stages of Alzheimer’s Disease (AD) or another type of Dementia (Alzheimer’s Association, 2017). Some of these changes have been identified in autopsies and brain imaging studies. These changes include; abnormal clumps of the amyloid protein which is associated with AD, a change in another type of protein known as Lewy Bodies which is associated with Dementia and the shrinkage of an important brain region called the hippocampus which effects memory (Mayo Clinic, 2016).
Since there is uncertainty over the causes, certain risks factors have been identified which could have an impact on the development of the disease. These risk factors can be increased with illness or lifestyle choices such as diabetes, hypertension, high cholesterol and the inability to partake in mentally or socially stimulating activities. The ageing process itself is irreversible and the risk of developing some form of Dementia increases with age (Mayo Clinic, 2017). The Alzheimer’s Association (2017) found 15-20% of adults aged 65 and over have Mild Cognitive Impairment (MCI).
Glisky (2007) has associated increased age with lower levels of performance in cognitive functioning and tasks which involve active manipulation, decision making and problem solving. A study conducted by Dudas and Clague et al (2005) used a Face Place Test, also known as the Cambridge Face Memory Test to examine episodic and semantic memory. 22 individuals with AD and 24 individuals with MCI took part. The results showed that both AD and MCI subjects were impaired on all components including person-naming, item recognition and the recall of spatial location. These results show that subjects with MCI are impaired in both episodic and semantic memory. A limitation of the Cambridge Face Memory Test is previous research has shown individuals have difficulty in recognising faces from another ethnic group. This may provide a reason for an impairment on item recognition (Germine & Duchaine et al, 2010). The degree of the diagnosed impairment and type of memory affected may therefore be exaggerated or inaccurate. However, despite this limitation, Glisky (2007) has recognised that semantic memory is affected during ageing though it is not impaired, just slower. Therefore, to improve the memory retrieval of individuals with Mild Cognitive Impairment (MCI), a cognitive based intervention may be used to assist cognitive functioning in older adults (Martin, 2011). Though, previous research has shown conflicting results with Gross et al (2012) stating, in advanced years, there is little benefit to be gained from cognitive training.
Meyer and Schvaneveldt (1971) claimed a variety of factors can affect a person’s ability to recall semantic information. Previous studies show that the frequency of a word can influence the recall rate. Whaley and Gordon (1978 &1983, as cited in Galambos et al, 2013) state words which are most commonly used in the English language are more likely to be recalled than words which are uncommon. Meyer and Schvaneveldt (1971) examined the effect of association between two words on recall time. 12 high school students were selected and were shown words which may either be related or unrelated semantically. Subjects were presented with four blocks of 24 test trials each. There was a total number of 16 nonword pairs, 32 word-nonword pairs, 24 pairs of associated words and 24 pairs of non-associated words. Before each trial began a fixation box appeared. After 1 second the stimulus appeared in the box prompting the subjects to press the appropriate key. The results showed that semantically related words have a priming effect on each other. Semantically related words are easier to recognise and aid the retrieval of similar words. A problem with studying semantic memory is, the items are stored serially, facilitation occurs in accessing stored information about associated words which means neural excitement in memory may be responsible for the associated effect (Schvaneveldt & Meyer,1973). Another problem with this research is the participants were all high school students, the ability to recall semantic information would not be reduced in healthy young adolescents compared to ageing individuals with Mild Cognitive Impairment (MCI) (Glisky, 2007)
- Conclusion
This review of literature aimed to give an insight into the current thoughts and investigations into the topic of MCI. The main reasons why this topic deserves further investigation is, with life expectancy increasing, there is more chance of a larger proportion of the population suffering from a cognitive impairment (Parliament, 2010). Once a person’s mental agility is impaired, there is an increased chance of that person developing Alzheimer’s Disease (AD). By understanding the causes and risk factors, treatments and interventions could be developed to arrest the progression of the disease. Though, researchers are currently working towards this. A decisive intervention has not yet been agreed upon and therefore more research is needed.
CHAPTER 2:
Methodology
(A Quantitative Study)
This chapter will discuss how previous research has influenced the data collection for this study.
2.1 Literature Review Resources
Whilst researching for this dissertation, several types of research were reviewed, such as journal articles, medical websites and the organisations associated with reduced cognitive functioning. After analysing the literature, the information most specific to this research was selected.
After reading various pieces of literature on the subject of MCI, the aims of this particular research project were decided upon and the methods previously used were amended slightly to aid the research.
2.2 Aims of research:
1) The aim of this research was to test the effectiveness of a cognitive based intervention on semantic memory and word retrieval operations in adults aged 60 years and over with Mild Non-Clinical Cognitive Impairment (MCI).
2) This research also aimed to see if this type of intervention could be used to slow down the progression of Alzheimer’s Disease (AD) in those who are already suffering from Mild Cognitive Impairment (MCI).
Participants
This section will discuss the recruitment method, the inclusion/exclusion criteria and the experimental design, sample size and gender of the participants
2.3 Recruitment Method:
All the participants selected for this study were recruited using a convenience sample. The main reason for using this type of sampling method was, with the time available for research, this method seemed most appropriate as the participants who agreed to take part were most readily available when the study commenced (Ellison et al, 2009).
2.4 Inclusion/Exclusion Criteria
All the participants who agreed to take part in the study had to meet certain criteria before being selected. The criteria set was as follows:
- Requirement no. 1: All the participants had to be aged 60 years and over and have Mild Non-Clinical Cognitive Impairment (MCI). This was due to Plassman (1995 as cited in Salthouse, 2009) who stated cognitive decline begins around aged 60.
- Requirement no. 2: All the participants had to have English as a first language as the experiment used words which are associated with the English language, therefore individuals who grew up speaking another language may be disadvantaged or unaware of some of the words in the English vocabulary.
- Requirement no. 3: The participants must not have been diagnosed with a serious brain disorder prior to the study which could have affected the person’s ability to remember or understand words. An example of a serious brain disorder associated with an inability to remember and understand words is Alzheimer’s Disease (AD) (NHS, 2016). Furthermore, this research was aimed towards halting the progression of this disease.
- Requirement no.4: The participants must also not have had a learning disability or barrier which effects how words are interpreted or displayed. An example of a learning barrier which effects the interpretation and display of words is Dyslexia (NHS, 2015). The difficulty in reading words would therefore invalidate the results.
- Requirement no. 5: The participants must also not be an avid user of brain training activities such as crosswords or sudoku puzzles, as the experiment is looking for an improvement following one of these types of interventions. Therefore, those who are accustomed to using puzzles may not show any change post intervention.
- Requirement no. 6: The final requirement relates to when the experiment is underway. Before starting the experiment, the participants must not have consumed any stimulants which could advantage the participants results. Some of these stimulants include coffee, tea and energy drinks (Encyclopedia of Health, 2010). The participants were however able to eat on the day of the study.
The failure to comply to these requirements would mean the study did not use a standardised procedure for each of the participants and therefore, the results may not be accurate or a reliable source which contributes towards the research field (Eysenck, 2002).
2.5 Experimental Design, Sample Size and Gender:
A repeated measures experimental design was used as the research was looking for a change in the same participants following a cognitive based intervention (Verma, 2015). A total number of 12 participants, both male and female, took part. The sample size was chosen based on Meyer and Schvaneveldt’s (1971) study.
Experiment
This section will give an overview of the study previously used by Meyer and Schvaneveldt (1971) paradigm as this research used the lexical decision paradigm created by the two researchers. This section will also detail the three phases of the experimental procedure and predict the results of the study based on two different types of hypothesis.
2.6 Overview:
Previously, both psychologists and psycholinguists have used a Lexical Decision Task (LDT) to examine mild impairments in semantic memory. The Lexical Decision Task (LDT) is most commonly used to study the internal workings of the mental lexicon. The task requires participants to classify visual stimuli as words or non-words as quickly and as accurately as possible. Analysis is therefore primarily based on the reaction times and error rates to the visual stimuli (Meyer and Schvaneveldt, 1971).
2.7 Procedure:
There were three phases to this experiment. The procedure was listed as below:
Phase 1:
At phase 1 of the experiment, participants over the age of 60 were required to complete a Global Deterioration Scale (GDS) (see Appendix A) which identified the level of impairment. The experiment required a diagnosis of Mild Cognitive Impairment (MCI) without being medically diagnosed by a doctor and therefore the best way to do this was through the use of a rating scale. The participants who scored a 2 or a 3 on the GDS were able to participate in the Lexical Decision Task (LDT). The original Meyer and Schvaneveldt (1971) lexical decision paradigm was used.
The paradigm displayed words on a computer screen and required participants to decide if both two letter strings revealed were words or non-words. The task included 24 pairs of semantically related words (BREAD-BUTTER) and 24 pairs of semantically unrelated words (BREAD-CONCRETE). 16 pairs of non-word pairs (ELUG-TEEHS) were also used along with 32 word-nonword pairs (BREAD-TSOAST). At the beginning of each of the 24 trials, a small fixation box appeared. After 1000 milliseconds the stimuli appeared in the box, one letter string centred above the other. The participants had to decide whether the stimulus type is the same or different, both words and non-words respectively. The participants had to select the answer by pressing on the appropriate key on the keyboard. In this instance, the “Z” key represented yes and the “?/” represented no. All the participant’s reaction times and error rates were collected and stored in the software known as SuperLab 5.
Phase 2:
During phase 2 of the study, the same participants were required to engage in a cognitive based intervention that consisted of a workbook containing a series of crossword puzzles. The crosswords were expected to be completed over a period of two weeks, 1 hour per day (See Appendix B)
Phase 3:
At the final stage of the experiment, phase 3, the participants repeated the Lexical Decision Task (LDT) previously underwent to test for possible improvements in semantic memory and lexical efficiency (word retrieval). All the data was analysed by SPSS.
2.8 Hypothesis:
Two types of hypotheses are listed below:
Null Hypothesis: There will be no difference in the participant’s semantic memory and word retrieval operations post the cognitive based intervention
Alternative Hypothesis: There will be a significant difference in the participant’s semantic memory and word retrieval operations post the cognitive based intervention
2.9 Ethics
Before carrying out research on human participants, it was important to review the British Psychological Society’s code of conduct on human research (2014). Reviewing these guidelines ensured that all the information gathered from the research was carried out within the stated guidelines, reducing ethical problems. The guidelines followed are listed below and can be seen in the Ethics Approval Form (Appendix C).
Informed Consent:
All the participants who agreed to take part were handed an informed consent letter which stated the aims of the research, what the study entailed and the length of time the study was expected to last. After reading the informed consent letter, the participants had to agree to take part in the study by drawing a tick in a box at the bottom of the page. In doing this, the participants gave informed consent.
Deception:
The participants who took part in this study were not deceived as the true aims of the research were provided in the informed consent letter. In making the aims of the research clear prior to the commencement of the study, the participants fully understood what the study entailed.
Right to Withdraw:
In the informed consent letter, the participants were made aware of the ability to withdraw from the study both during and after the study had been completed. All data recorded from the participants would not be used in the final paper had any withdrawn from the study. Furthermore, the contact details of myself and supervisor were detailed on the consent form, should a wish to withdraw be expressed.
Confidentiality:
All the participant’s information was kept private and not discussed with any other participant in the study. All participants were not named and were labelled from 1-12 to ensure confidentiality.
Protection from Harm:
During the study, all participants were protected from harm due to the right to withdraw and the absence of hurtful and offensive language in the Lexical Decision Task (LDT).
Debriefing:
At the end of the study, the participants were given a debriefing letter which reiterated what the informed consent letter detailed. This was to remind the participants of the study undertaken.
CHAPTER 3:
Analysis of Results
This section will analyse the results obtained in the Lexical Decision Task (LDT) prior and post the cognitive based intervention. All the data was analysed using SPSS software. The significance level was set to 0.05.
3.1 Table 1
| Gender | |||||
| Frequency | Percent | Valid Percent | Cumulative Percent | ||
| Valid | Male | 6 | 50.0 | 50.0 | 50.0 |
| Female | 6 | 50.0 | 50.0 | 100.0 | |
| Total | 12 | 100.0 | 100.0 | ||
A total number of 12 participants took part in this research. 6 participants were male (50%) and 6 participants were female (50%).
3.2 Table 2
| Statistics | ||
| Age | ||
| N | Valid | 12 |
| Missing | 0 | |
| Mean | 72.75 | |
| Median | 73.50 | |
| Minimum | 60 | |
| Maximum | 91 | |
All the 12 participants were aged 60 years and over with the minimum age being 60 and the maximum age being 91. The average age of the total number of participants was 73 years (M =72.75) with the middle age being 74 years (Mdn = 73.50).
3.3 Table 3
| Descriptive Statistics | ||||||
| WORD OR NONWORD | N | Mean | Std. Deviation | Minimum | Maximum | |
| word vs word | REACTION TIME PRIOR TO INTERVENTION | 1147 | 1542.44 | 964.679 | 435 | 8289 |
| REACTION TIME POST TO INTERVENTION | 1151 | 2054.55 | 1699.505 | 536 | 45903 | |
| nonword vs word | REACTION TIME PRIOR TO INTERVENTION | 774 | 1538.06 | 1004.848 | 450 | 8273 |
| REACTION TIME POST TO INTERVENTION | 775 | 2215.53 | 1078.475 | 680 | 12026 | |
| nonword vs nonword | REACTION TIME PRIOR TO INTERVENTION | 373 | 1554.61 | 830.780 | 443 | 5157 |
| REACTION TIME POST TO INTERVENTION | 377 | 2052.47 | 913.716 | 753 | 6273 | |
A nonparametric Wilcoxon Signed Rank Test was conducted to compare two related samples reaction times pre and post cognitive based intervention. Table 3 shows the reaction times of the participants to different word type pairs. Prior to the cognitive based intervention, 1147 scores for word vs word word pairs were analysed. The results showed that the minimum reaction time was 435 milliseconds and the maximum reaction time was 8289 milliseconds. The average reaction time of these scores was 1542.4 milliseconds (M = 1542.44) with a standard deviation of 964.68 (SD = 964.679). Post the cognitive based intervention, 1151 scores for word vs word word pairs were analysed. The results showed that the minimum reaction time was 536 milliseconds and the maximum reaction time was 45903 milliseconds. The average reaction time of these scores was 2054.6 milliseconds (M=2054.55) with a standard deviation of 1699.5 (SD = 1699.505). Based on the means between both tests, the reaction times for word vs word were faster prior to the cognitive based intervention.
The reaction times prior and post the cognitive based intervention were also analysed for nonword vs word type pairs. 774 scores prior to the cognitive based intervention were analysed. The results showed that the minimum reaction time was 450 milliseconds and the maximum reaction time was 8273 milliseconds. The average between these results was 1538.1 milliseconds (M = 1538.06) with a standard deviation of 1004.85 (SD= 1004.848). Post the cognitive based intervention, 775 scores were analysed. The results showed that the minimum reaction time was 680 milliseconds and the maximum reaction time was 12026 milliseconds. The average score between these results was 2215.5 milliseconds (M= 2215.53) with a standard deviation of 1078.48 (SD= 1078.475). Again, based on the means between both tests, the reaction times for nonword vs word were faster prior to the cognitive based intervention.
The reaction times were also analysed for the nonword vs nonword word type pairs prior and post cognitive based intervention. 373 scores prior to the cognitive based intervention analysed. The results showed that the minimum reaction time was 443 milliseconds and the maximum reaction time was 5157 milliseconds. The average score between these results was 1554.6 milliseconds (M=1554.61) with a standard deviation of 830.8 (SD=830.780). Post the cognitive based intervention, 377 scores were analysed. The results showed that the minimum reaction time was 753 milliseconds and the maximum reaction time was 6273 milliseconds. The average reaction time between the two scores was 2052.5 milliseconds (M= 2052.47) with a standard deviation of 913.72 (SD= 913.716). Based on the two means between both tests, the reaction times for nonword vs nonword were faster prior to the cognitive based intervention.
Overall, the reaction times for word vs word, nonword vs word and nonword vs nonword were faster prior to the cognitive based intervention.
3.4 Table 4
| Ranks | |||||
| WORD OR NONWORD | N | Mean Rank | Sum of Ranks | ||
| word vs word | REACTION TIME POST TO INTERVENTION – REACTION TIME PRIOR TO INTERVENTION | Negative Ranks | 337a | 523.38 | 176378.50 |
| Positive Ranks | 808b | 593.70 | 479706.50 | ||
| Ties | 1c | ||||
| Total | 1146 | ||||
| nonword vs word | REACTION TIME POST TO INTERVENTION – REACTION TIME PRIOR TO INTERVENTION | Negative Ranks | 183a | 313.63 | 57395.00 |
| Positive Ranks | 590b | 409.76 | 241756.00 | ||
| Ties | 1c | ||||
| Total | 774 | ||||
| nonword vs nonword | REACTION TIME POST TO INTERVENTION – REACTION TIME PRIOR TO INTERVENTION | Negative Ranks | 118a | 153.14 | 18070.00 |
| Positive Ranks | 255b | 202.67 | 51681.00 | ||
| Ties | 0c | ||||
| Total | 373 | ||||
| a. REACTION TIME POST TO INTERVENTION < REACTION TIME PRIOR TO INTERVENTION | |||||
| b. REACTION TIME POST TO INTERVENTION > REACTION TIME PRIOR TO INTERVENTION | |||||
| c. REACTION TIME POST TO INTERVENTION = REACTION TIME PRIOR TO INTERVENTION | |||||
Table 4 shows the number of cases which have a negative rank, positive rank and ties. For word vs word, 1146 scores were analysed. The results showed that in 337 cases, the post intervention had faster response rate times than the pre intervention. The average response rate time was 523.4 milliseconds (M= 523.38). However, in 808 cases, the response rate times were slower post intervention. The average score of these cases was 593.7 milliseconds (M=593.70). There was also a tied score of 1. These results showed that although the post intervention scored favourable in 337 cases, 808 times this was not the case. Overall, the response rate times were faster prior to the intervention for the word vs word pairings.
In the nonword vs word type pairs, 774 scores were analysed. The results showed that in 183 cases the post intervention had faster response rate times than the pre intervention. The average response rate time was 313.6 milliseconds (M= 313.63). Conversely in 590 cases the response rate times were slower post intervention. The average score for these cases was 410 milliseconds (M= 409.76). There was also a tied score of 1. Overall, the response rate times were faster prior to the intervention for the word vs nonword pairings.
In the nonword vs nonword word type pairs, 373 scores were analysed. The results showed that in 118 cases the post intervention had faster response rate times than the pre intervention. The average response rate time was 153.1 milliseconds (M= 153.14). Though, in 255 cases the response rate times were slower post intervention. The average score of these cases was 202.7 milliseconds (M= 202.67). There were also 0 ties between the two tests. Overall, the response rate times for the nonword vs nonword pairings were faster prior to the intervention.
On the whole, the response rates were slower for the post intervention on all word type pairs.
|
3.5 Table 5 Test Statistics |
||
| WORD OR NONWORD | REACTION TIME POST TO INTERVENTION – REACTION TIME PRIOR TO INTERVENTION | |
| word vs word | Z | -13.551b |
| Asymp. Sig. (2-tailed) | .000 | |
| nonword vs word | Z | -14.844b |
| Asymp. Sig. (2-tailed) | .000 | |
| nonword vs nonword | Z | -8.065b |
| Asymp. Sig. (2-tailed) | .000 | |
|
||
Table 5 shows the Z scores for the reaction times of each word type: word vs word (Z= -13.551), nonword vs word (Z= -14.844) and nonword vs nonword (Z= -8.065). When hypothesis testing, a Z score below 0 would reject the null hypothesis (Wade & Tavris, 1996). Therefore, with negative results in each case, the null hypothesis is rejected and the alternative hypothesis is accepted. The significance level on all the word type pairs is P<.001. This shows that the results were statistically significant.
The alternative hypothesis for this research was “There will be a significant difference in the participant’s semantic memory and word retrieval operations post the cognitive based intervention”. In this particular case, participants showed a change in reaction times post the cognitive based intervention. The overall conclusion of the results is the participant’s reaction times became slower post the intervention
CHAPTER 4:
Discussion
This chapter will discuss the findings of the study in relation to previous literature and will examine the strengths and weaknesses of the study conducted.
4.1 Aims
The aims of this research were to test the effectiveness of a cognitive based intervention on semantic memory and word retrieval operations in adults aged 60 years and over with Mild non-clinical Cognitive Impairment (MCI). This dissertation sought to find out if this type of intervention would be the best suited method at slowing down the progression of Alzheimer’s Disease (AD) in those who have Mild Cognitive Impairment (MCI).
To test the effectiveness of the cognitive based intervention, participant’s reaction times to word and nonword pairs were compared pre and post the intervention. In order for the intervention to be deemed as effective, an improvement in reaction times would be noted in the post intervention. The results showed a negative change in the participant’s results as the reaction times slowed post the intervention. This would suggest that this type of cognitive based intervention may not be the best suited method at slowing down the progression of Alzheimer’s Disease (AD) in those who have Mild Cognitive Impairment (MCI). To understand why the participant’s reaction times worsened in the post intervention, further investigation may be needed.
4.2 Literature
By reviewing the previous literature, comparisons between the results, statements and studies can be made. As previously stated by Plassman et al (1995, as cited in Salthouse, 2009) cognitive decline begins around the age of 60 years old. The Alzheimer’s Association (2017) also stated Mild Cognitive Impairment (MCI) effects 15-20% of the over 65’s. The results from the Global Deterioration Scale (GDS) supports both of these statements as the participants aged between 60 and 91 years old showed cognitive decline and had a form of Mild non-clinical Cognitive Impairment (MCI). The results however showed that participants under the age of 65 had MCI, which could suggest that the onset of the disease begins around age 60 or even earlier. Albert and Heaton (1998, as cited in Salthouse, 2009) suggested that this decline could begin as early as age 50.
Mild Cognitive Impairment (MCI) is an extensive scale and therefore the level of cognitive and functional impairment can have an impact on the varied outcomes of the disease (Roberts and Knopman, 2013). For instance, in this case, the participant’s reaction times slowed in the post intervention, which could suggest the degree of MCI worsened. The widespread spectrum of the disorder meant participants were impaired at different points on the Global Deterioration Scale (GDS). For example, Reisberg et al (1983) suggests individuals with Mild Cognitive Impairment (MCI) score either a 2 or a 3 on the GDS. The point in which the participants are impaired could have affected the reaction times in both trials. A person who scored a 2 on the GDS may have had faster response rate times than those who scored a 3 on the GDS. This could also help explain the broad range of minimum and maximum response rate times recorded amongst the word type pairs. Likewise, the type of MCI subtype affecting the individual could have had an influence on the results and reaction times obtained as the naMCI subtype effects several cognitive domains besides memory. This could have further affected the person’s attention span and language skills in this study.
When comparing the results of this study against aforementioned studies, similarities and differences can be made between some of the findings. Meyer and Schvaneveldt (1971) found reaction times were faster to words which were semantically related. Whaley and Gordon (1978 &1983, as cited in Galambos, 2013) proposed words which are more commonly used in the English language are more likely to be recognised than less frequently used words. The results obtained support Meyer and Schvaneveldt (1971) findings as participant’s minimum reaction times were fastest in the word vs word word pairs prior (min= 435) and post (min= 536) the intervention. An explanation for this could be, the words presented were semantically related or were frequently used in the English language (Whaley & Gordon 1978 & 1983, as cited in Galambos, 2013). However, the word vs word pairs maximum reaction time was the highest compared to any other word types maximum reaction time in both the pre (max= 8289) and post (max= 45903) intervention. This could be due to the words not being semantically related or not commonly used in the English Language. Conversely, the shortest maximum reaction time in the pre (max= 5157) and post (max= 6273) intervention came from the nonword vs nonword word pairings. Participant’s seemed to be able to recognise nonsense words in a shorter length of time.
Overall, the results from the Lexical Decision Task (LDT) showed that participants reaction times worsened in the post intervention, meaning Martin’s (2011) statement about cognitive interventions assisting cognitive functioning in older adults is disproved. Gross’ (2012) statement of conflicting evidence regarding this theory is therefore accepted.
4.3 Strengths and Limitations
Research Method:
This study used an experimental method to gather data for this research. A strength of using this type of research method is the use of a standardised procedure. Standardised procedures allow researchers to replicate the study, increasing the reliability if similar or the same results are found. The results can then be checked and verified against other comparable results (Bernard, 2012). This study used a standardised procedure as all the participants had to meet 6 requirements before being able to partake. The participants each completed the same GDS scale, the same Lexical Decision Task (LDT) and the same set of crossword puzzles, making the experiment unbiased. The results from the standardised procedure could be flawed if the participants did not follow some of the 6 requirements or omitted the cognitive based intervention. Often, experiments are carried out in artificial environments which makes generalisation to real-life settings difficult (Bernard, 2012). Unlike most experiments, this study was carried out in the familiar setting of the participant’s own homes. This makes the results more plausible and increases ecological validity. A problem with conducting experiments in real-life settings is control over extraneous variables may be impossible, as the researcher has less control over the variables (Neuman, 2006). For example, in this research, each Lexical Decision Task (LDT) was carried out across numerous homes making it impossible to foresee the participant’s health, mood and daily events which could influence the performance level of each participant. Another extraneous variable which could have affected the results of the study is human error. Human error occurs when participants make mistakes which are not intended to be part of the research (Creswell, 2013). In this study, participants made mistakes by making keyboard errors. This led to ultra-fast keyboard reactions that were registered as errors. These were clearly outliers and would affect the validity of the study. To resolve this issue, the outliers were removed.
Recruitment Method:
All the participants for this research were gathered using a convenience sample. A strength of using this type of sampling method is, all the participants used were most readily available when the study commenced. A problem with using a convenience sample is the researcher makes no attempt to know the population or use a random process to select participants. Therefore, there is little control over the representation of the sample which could lead to researcher bias. In this study, a convenience sample was used which meant the sample consisted of family members, neighbours and family friends. To overcome the issue of a biased sample and researcher bias, the study used individuals who lived within a 2 mile radius, had different academic skills, gender and age. By ensuring this selection, it could be fairly representative of the general public and wider population (Gravetter et al, 2011). Despite the limitations of convenience sampling, this method is most commonly used than any other type of sampling method. A reason for this is, it is the least time consuming method to gather the desired amount of participants for research compared to probability sampling. This is due to probability sampling requiring the identification of each member of the population which can end up being a lengthy process (Gravetter, 2011).
Experimental Design
This research used a repeated measures also known as a within-subjects experimental design. This design requires each participant to partake in every condition on each trial. A strength of using this design is it eliminates the effects of individual differences as the same participants complete both trials. The person’s IQ, ability, gender and age remain the same during both trials. A disadvantage of using a repeated measures experimental design is subjects need to be tested under both or several conditions. This requires the participant’s to be available over long periods of time or be willing to partake in multiple sessions (Myers & Well et al, 2013). If people retract the agreement to complete the study at any point, this can make the research process longer. Fortunately, in this study, all participants completed both trials. This was the advantage of using only 12 participants and having a research process that would not impinge on the participant’s daily lives over a long period of time. Although, the research was short, participants could still be affected by order effects. Order effects are especially problematic in repeated measures designs as the order in which the experimental materials are presented can have an impact on the outcome of the study. For instance, in reaction time studies, participants may show improvement in reaction time speed as a result of practising the task (Shaughnessy et al, 2008). However, in this study, this was not the case as participant’s reaction times slowed post the intervention. Another factor that can affect the outcome of the study is fatigue. Often, if tasks are uninteresting or repetitive participants may become bored and lose interest in the task at hand. This could reduce performance levels, which has an impact on the results. Those with a shortened attention span may rush through the task to relieve boredom and those with a lack of motivation may slow down with disinterest (Shaughnessy et al, 2008). To control order effects in this study, word pairs were assigned randomly pre and post the intervention.
CHAPTER 5:
Conclusion
5.1 Summary
The preliminary aims of this research were to test the effectiveness of a cognitive based intervention on semantic memory and word retrieval operations in adults aged 60 years and over with Mild non-clinical Cognitive Impairment (MCI). This dissertation sought to find out if this type of intervention could be used to slow down the progression of Alzheimer’s Disease (AD) in those who have Mild Cognitive Impairment (MCI. Based on the results obtained in this research, the cognitive based intervention did not improve the semantic memory and word retrieval of those taking part. It could be suggested that this intervention would not be the best suited method for slowing down the progression of Alzheimer’s Disease (AD) in those who have Mild Cognitive Impairment (MCI). The research would need to be repeated in order to verify the findings from this study.
5.2 Future Recommendations
If this study were to be repeated, a few suggestions could be:
- To lengthen the time between phase 2 and phase 3 of the experiment:
The two week timescale for workbook completion could be increased to give the participants the opportunity to complete all the puzzles and relieve pressure of an intense, tight schedule. The two week timescale may also not be long enough to truly detect a change in a person’s cognition.
- Follow-up participants (longitudinal study)
After the study has been completed, participants could be revisited to check for improvements following the intervention and to monitor the progression of the disease. Although there is no universally accepted time for follow up periods, Weiner et al (2003) suggests 3-6 month follow ups have proven to be inadequate at determining the long term effects of an intervention program. Therefore, a recommendation would be to revisit the participants on an annual basis.
- Reduce the amount of word pairings
In relation to the time taken to complete the task, around 20 minutes for each session, a reduction in the word type pairs might be preferable to eliminate some of the problems associated with order effects (Shaughnessy et al, 2008). Although the words in this study were assigned randomly pre and post intervention, the tasks themselves seemed lengthy to some of the participants which could still present a problem in regards to boredom, low attention span and a lack of motivation.
- Serial Processing (word placement)
Serial processing is the act of recognising and processing words one at time (Geissler, 2000). The speed at which words or nonwords are recognised is dependent upon where the words are placed within the fixation box. For example, reaction times may be faster to words placed above nonwords or vice versa. This could be an interesting area of research to understand how the brain processes the information presented and how it could affect reaction times.
REFERENCES
Alzheimer’s Association. (2017). Mild Cognitive Impairment. Retrieved from http://www.alz.org/dementia/mild-cognitive-impairment-mci.asp.
Bernard, H.R. (2012). Social Research Methods Qualitative and Quantitative Approaches (2nd ed.). United States of America: SAGE publications.
Choi, S.H. (2003). Interchanging Scores Between Clinical Dementia Rating Scale and Global Deterioration Scale. National Center for Biotechnology Information, 17 (2), 98-105. Retrieved from https://www.ncbi.nlm.nih.gov/labs/articles/12794387/.
Creswell, J.W. (2013). Research Design: Qualitative, Quantitative and Mixed Methods Approaches (4th ed.). United States of America: SAGE publications.
Dudas , R.B. & Clague et al, F. (2005). Episodic and semantic memory in mild cognitive impairment. Neuropsychologia, 43 (9), 1266-1276. doi: http://doi.org/10.1016/j.neuropsychologia.2004.12.005.
Eisdorfer et al, C. (1992). An empirical evaluation of the Global Deterioration Scale for staging Alzheimer’s Disease, American Journal of Psychiatry, 149 (8) 190-190. doi: 101176/ajp.149.2.190
Ellison et al, S.L.R. (2009). Practical Statistics for the Analytical Scientist: A Bench Guide. United Kingdom: Royal Society of Chemistry.
Encyclopedia of Health (2010), Volume 1. New York: The Rosen Publishing Group.
Eysenck, M.W. (2002). Simply Psychology. United Kingdom: Taylor and Francis.
Galambos et al, J.A. (2013). Knowledge Structures. United Kingdom: Psychology Press.
Geissler, E.A. (2000). Modern Issues in Perception. Netherlands: Elsevier.
Germine, L. & Duchaine, B et al. (2010). A new selective developmental deficit: impaired object recognition with normal face recognition, Cortex. doi: 10.1016/j.cortex.2010.04.009
Glisky, E.L. (2007). Brain Aging: Models, Methods, and Mechanisms. United Kingdom: Taylor and Francis.
Gravetter et al, F.J. (2011). Research Methods for the Behavioral Sciences (4th ed.). United States of America: Cengage Learning.
Gross et al, A.L. (2012). Memory training interventions for older adults: A meta-analysis. Aging and Mental Health, 16 (6), 722-734. doi: 10.1080/13607863.2012.667783.
Gubrium, J.F. & Holstein, J.A. (2002). Handbook of Interview Research: Context and Method. United States of America: SAGE Publications.
Huckans et al, M. (2013). Efficacy of cognitive rehabilitation therapies for mild cognitive impairment (MCI) in older adults: working toward a theoretical model an evidence-based intervention. National Center for Biotechnology Information, 23 (1), 63-80. doi: -10.1007/s11065-013-9230-9
Martin et al, M. (2011). Cognition-based interventions for healthy older people and people with mild cognitive impairment. Cochrane Database of Systematic Reviews, 19 (1). doi: 10.1002/14651858.CD006220.pub2
Mayo Clinic. (2016). Mild Cognitive Impairment (MCI). Retrieved from: http://www.mayoclinic.org/diseases/conditions/mild-cognitive-impairment/symptoms-causes/dxc-20206111.
Meyer, D. E. & Schvaneveldt, R.W. (1971). Facilitation in recognising pairs of words-Evidence of a dependence on retrieval operations. Journal of Experimental Psychology, 90 (2), 227-230. doi: – 10.1037/h0031564.
Myers, J.L. & Well et al, A.D. (2013). Research Design and Statistical Analysis (3rd ed.). United Kingdom: Routledge.
National Health Service (NHS). (2015). Dyslexia – Symptoms . Retrieved from http://www.nhs.uk/Conditions/Dyslexia/Pages/Symptoms.aspx.
National Health Service (NHS). (2016). Alzheimer’s disease – Symptoms. Retrieved from http://www.nhs.uk/Conditions/Alzheimers-disease/Pages/Symptoms.aspx.
Neuman, W.L. (2006). Social Research Methods: Qualitative and Quantitative Approaches (2nd ed.). Toronto: Pearson.
Parliament UK. (2010). The ageing population: key issues for the 2010 Parliament. Retrieved from http://www.parliament.uk/business/publications/research/key-issues-for-the-new-parliament/value-for-money-in-public-services/the-ageing-population/.
Petersen et al, R.C. (2001). Current Concepts in Mild Cognitive Impairment. Arch Neurol, 58 (12). Retrieved from: http://www.memory-clinic.at/mcipetersen.pdf.
Petersen, R.C. (2004). Mild Cognitive Impairment as a diagnostic entity. Journal of Internal Medicine, 256 (3), 183-194. doi: 10.1111/j.1365-2796.2004.01388.x.
Reisberg et al, B. (1983). The Global Deterioration Scale for Assessment of Primary Degenerative Dementia. American Journal of Psychiatry, 139. 1136-1139.Retrieved from: https://www.fhca.org/members/qi/clinicadmin/global.pdf.
Roberts, R. & Knopman, D. (2013). Classification and Epidemiology of MCI. National Center for Biotechnology Information, 29 (4), 753-772. doi: 10.1016/j.cger.2013.07.003.
Salthouse, T.A. (2009). When does age-related cognitive decline begin?. Neurobiology of Aging, 30 (4), 507-514. doi: 10.1016/j.neurobiolaging.2008.09.023.
Schvaneveldt, R.W. & Meyer, D.E. (1973). Retrieval and Comparisons Process in Semantic Memory. In S. Kornblum (Ed.) Attention and Performance IV (pp. 395-409). United States of America: Academic Press.
Shaughnessy et al, J.J. (2008). Research Methods in Psychology (8th ed.). United Kingdom: McGraw-Hill Higher Education.
The British Psychological Society (2014) Code of Human Research Ethics. Retrieved from: http://www.bps.org.uk/system/files/Public%20files/code_of_human_research_ethics_dec_2014_inf180_web.pdf
Wade, C. & Tavris, C. (1996). Psychology (4th ed.). United Kingdom: HarperCollins.
Weiner et al, I.B. (2003). Handbook of Psychology: Health Psychology. United States of America: Wiley.
Appendix A
Global Deterioration Scale (GDS)
Stage 1: No cognitive decline
- Experiences no problems in daily living.
Stage 2: Very mild cognitive decline
- Forgets names and locations of objects.
- May have trouble finding words.
Stage 3: Mild cognitive decline
- Has difficulty travelling to new locations.
- Has difficulty handling problems at work.
Stage 4: Moderate cognitive decline
- Has difficulty with complex tasks (finances, shopping, planning dinner for guests).
Stage 5: Moderately severe cognitive decline
- Needs help to choose clothing.
- Needs prompting to bathe.
Stage 6: Severe cognitive decline
- Loss of awareness of recent events and experiences.
- Requires assistance bathing; may have a fear of bathing.
- Has decreased ability to use the toilet or is incontinent.
Stage 7: Very severe cognitive decline
- Vocabulary becomes limited, eventually declining to single words.
- Loses ability to walk and sit.
- Requires help with eating.
Appendix B:
PHASE 2:
WORKBOOK
(CROSSWORD PUZZLES)
ONE:
Across Down
8. Abominable Snowman (4) 1. Stunt Flying (10)
9. Official examination (10) 2. Exhibits (8)
10. Dormant (6) 3. Language of India (10)
11. Edible marine bivalves (8) 4. Demands (4)
12. Dad (4) 5. Plateau (4)
13. Flight attendant (10) 6. Impassive (6)
17. Perishes (4) 7. A type of liquid food (4)
18. Small terrestrial lizard (5) 14. Electronic letters (5)
19. Autumn (4) 15. Deductive (10)
20. Particularly (10) 16. The end of an Apollo flight (10)
22. Constellation bear (4) 19. Quartet (8)
23. Precarious (8) 21. Whole (6)
27. Not outside (6) 24. Require (4)
28. Unglazed earthenware (10) 25. Baroque composer (4)
29. Cut (4) 26. Dines
TWO:
Across
9. Anxious (7)
10. Drool (7)
11. Hearable (7)
12. Luxurious (7)
13. Brine (9)
15. Fruity-Smelling compound (5)
16. A small kitchen appliance (7)
19. Wander aimlessly (7)
20. Mistake (5)
21. Becoming proficient (9)
25. Nightclub (7)
26. Walk emphatically (7)
28. Insert (7)
29. Fasten (7)
Down
1.Chronicles (6)
2. Pertaining to a bride (6)
3. Newbie (slang) (4)
4. View (6)
5. Graphic Symbol (8)
6. Vilify (10)
7. Disapproved (8)
8. Educator (8)
14. Rainproof (10)
16. Carved deeply into (8)
17. Cardiopulmonary exercises (8)
18. One who makes payment (8)
22. Personal security (6)
23. Set a flame (6)
24. Putting surfaces (6)
27. Unrestrained revelry (4)
THREE:
Across
1.Governance (1)
10. Malicious burning (5)
11. Ceramic ware (9)
12. Male ruler of an empire (7)
13. Far beyond a norm (7)
14. Utilisers (5)
16. Cutbacks (9)
19. Circumference (9)
20. Hair net (5)
22. Pretentious (7)
25. Antiquated (7)
27. Association (9)
28. Discrimination against the elderly (5)
29. Achievement (14)
Down
2.Vanish (9) 24. Oar (5)
3. Not outer (5) 26. Allegation (5)
4. Crucial (9)
5. Half of six (5)
6. Vigilance (9)
7. Absurd (5)
8. Convent (7)
9. Boat (6)
15. Conference (9)
17. Pennants (9)
18. Separation (9)
19. A mild powered seasoning (7)
21. Leave suddenly (6)
23. Melodies (5)
FOUR:
Across
8. Modify (4)
9. Positive pole (5)
10. Leave out (4)
11. Perplex (6)
12. Encirclement (8)
13. Breaking and entering (8)
15. Ascribe (6)
17. Not an art (7)
19. Violent rotating windstorm (7)
22. Scant (6)
24. Fury (8)
26. Marine Crustacean (8)
28. Termagants (6)
30. Learning method (4)
31. Well hyphened known (5)
32. Make do (4)
Down
1.Border (4) 18. A curved shape (8)
2. Fight (8) 20. A black candy (8)
3. Photographic necessity (6)
4. Cattleman (7) 21. Outcomes (7)
5. Speed (8) 23. Eluted (6)
6. Come up with (6) 25. Dwell (6)
7. Discover (4) 27. Affirm (4)
14. Open, as a bottle (5) 29. Sponge (4)
16.Basic Belief (5)
FIVE:
Across
6. Recuperate (7)
7. Rehabilitation (5)
9. Hairdo (4)
10. Make legal (10)
11. Those without seats (18)
13. Influx (6)
15. Kind of bean (4)
17. Coming and………. (5)
18. Orange Pekoe (4)
19. Gap (6)
20. Described (8)
23. Dispense (10)
26. Classify (4)
27. Audacity (5)
28. Our language (7)
Down
1.Bookkeeper (10) 22. Our Planet (5)
2. Slender (6) 24. Faeces (4)
3. Naval jail (4) 25. Utilized (4)
4. Squirming (8)
5. Levelling wedge (4)
6. Fit out again (5)
8. Rocket Launcher (7)
12. Bake in a shallow dish (5)
14. What some science fiction is (10)
16. Belief (7)
17. Rumourmonger (8)
21. Promise (6)
SIX:
Across
6. Clothed in finery (7)
7. Affirms (5)
9. Holes (4)
10. Study of mental disorders (10)
11. Ancestry (8)
13. Responds (6)
15. Lash (4)
17. Impressive in Scale (5)
18. Point where two curves meet (4)
19. Light brownish colour (6)
20. Giggled (8)
23. Benevolences (10)
26. Hotels (4)
27. Fully developed (5)
28. People watching their calories (7)
Down
1.Believer (10) 17. Three-masted ships (8)
2. Marksman (6) 21. Tuft of loose cords (6)
3. Lazily (4) 22. Sea eagles (5)
4. Amassed (8) 24. Let fall to the ground (4)
5. A midwestern state (4) 25. Pop (4)
6. Nimble (5)
8. Fairies (7)
12. Precise (5)
14. Recognised (10)
16. Dancing (slang) (7)
SEVEN:
Across
6.Dried Grapes (7)
7. Damp (5)
9. Alliance of countries (4)
10. Annoying (10)
11. Gnashing (8)
13. Declare not guilty (6)
15. Capital of Latvia (4)
17. Not quietly (5)
18. Creativity (4)
19. Respite (6)
20. Nirvana (6)
23.Declaration (10)
26. Chamber (4)
27. Moan (5)
28. Chemical (7)
Down
1.A city in Ohio (10) 21. Leased (6)
2. Two piece bathing suit (6)
3. Exploiter (4) 22. Nose (slang) (5)
4. Bread of sheep dog (8) 24. Fragrance (4)
5. Send fourth (4) 25. Angers (4)
6. Measuring stick (5)
8. Tooth doctor (7)
12. Mob (5)
14. Dilemmas (10)
16. Floating mass of frozen water (7)
17. Wealthy (8)
EIGHT:
Across
1.A long narrow sled without runners (8)
5. Static balance (6)
9. Indolence (8)
10. Ring of colour around the nipple (6)
12. The passing of a law (9)
13. Nude (5)
14. Long haired Tibetan oxen (4)
16. Pillage (7)
19. Oval (7)
21. A type of fruit (4)
24. Heath (5)
25. Gaunt (9)
27. A top worn by women
28. Seppuku (8)
29. Sell again (6)
30. Connoisseur (8)
Down
1.Rudder lever (6)
2. A street of small shops (6) 15. Assessment (9)
3. Agile Old World viverrine (5) 17. Recall (8)
4. A localised collection of pus (7) 18. Chicago state (8)
6. Large hair tropical spider (9) 20. Sword (4)
7. Concentration camp (8) 21. Mollify (7)
8. Norm (8) 22. Endeavour (6)
11. Stair (4) 23. Counsel (6)
26. Unsuitable (5)
NINE:
Across
1.Leader of 100 soldiers (9)
6. Farewell (5)
9. Especially fine clothing (7)
10. Belligerent mood (7)
11. Amazing (7)
12. A mild powered seasoning (7)
13. Crow foot flower (9)
15. Candied (5)
14. SSSS (5)
19. District (9)
22. Hole in a lock (7)
23. Strong and sharp (7)
25. Artists loft (7)
26. Set apart (7)
27. Chores (5)
28. Sedimentary rock (9)
Down
1.About (5) 14. Large church (9)
2. Leave undone (7) 17. Timidity (7)
3. Release (7) 18. Tales (7)
4. Picture (5) 20. Pyrogenic (7)
5. A publication of current events (9)
6. Germane (7) 21. Marjoram (7)
7. Envisage (7) 23. Light refractor (5)
8. Insalubrious (9) 24. Motif (5)
13. Morning meal (9)
TEN:
Across
1.Ectasy (7)
5. One of Batman’s foes (7)
9. Long string pasta (9)
10. Informal language (5)
11. Disappointment (7)
12. Chemical (7)
13. Beyond normal limits (9)
15. Electrical pioneer Nikola (5)
17. Divided (5)
19. Negated (9)
22. Sharp shooter (7)
25. Radiating (7)
26. Shovel (5)
27. Acquaint (9)
28. Cold symptom (7)
29. Used for sewing and knitting (7)
Down
1.Settle conclusively (7) 23. South American bird (5)
2. Pragmatic (9) 24. Leave out (5)
3. Detaches (7)
4. Addition (9)
5. Increase (5)
6. Cake or pie (7)
7. Rent (5)
8. Boat races (7)
14. Make understand (9)
16. A kind of religious song (9)
17. They like inflicting pain (7)
18, Thence (7)
20. A variant of an element (7)
21. Deviate (7)
Appendix C:
Ethics Approval Form
Part One
| Title of project: The effectiveness of a cognitive based intervention on semantic memory and retrieval operations in adults over 60 years with mild cognitive impairment. |
| YES | NO | N/A | ||
| 1 | Will you describe to participants what will happen in your study (e.g. experimental or interview procedures) in advance, so that they are informed about what to expect? | X | ||
| 2 | Will you tell participants that their participation is voluntary? | X | ||
| 3 | Will you obtain written consent for participation? | X | ||
| 4 | If the research is observational, will you ask participants for their consent to being observed? | X | ||
| 5 | Will you tell participants that they may withdraw from the research at any time and for any reason? | X | ||
| 6 | With questionnaires and interviews, will you give participants the option of omitting questions they do not want to answer? | X | ||
| 7 | Will you tell participants that their data will be treated with full confidentiality and that, if published, it will not be identifiable as theirs? | X | ||
| 8 | Will you debrief participants at the end of their participation (i.e. Give them a brief explanation of the study)? | X |
If you have ticked No to any of Q1-8, please make sure you give an explanation on Part Two of the form.
[Note: N/A = not applicable]
| YES | NO | N?A | ||
| 9 | Will your project involve deliberately misleading participants in any way? | X | ||
| 10 | Is there any realistic risk of any participants experiencing either physical or psychological distress or discomfort? If Yes, give details in part two of this form, and state what you will tell them to do if they should experience any problems (e.g. who they can contact for help). | X | ||
| 11 | Does your project involve work with animals?
. |
X | ||
| 12 | Do participants fall into any of the following special groups? If they do, please refer to the guidance notes and provide the justification required in part 2 Q6.
Prisoners, children (under 18), NHS patients, NHS staff, Social Services clients and other vulnerable adults. |
X |
Part 2
- Title of project: The effectiveness of a cognitive based intervention on semantic memory and retrieval operations in adults over 60 years with mild nonclinical cognitive impairment.
- Purpose of project and its academic rationale:
The purpose of this project is to investigate the effectiveness of a cognitive based intervention on semantic memory and retrieval operations in adults over 60 years with mild nonclinical cognitive impairment. The boundary between normal aging and early onset or mild dementia is currently an intense area of interest in the field of psychology and aging. A slight cognitive impairment, typically memory, with otherwise normal performance in adults has been operationalised as mild cognitive impairment (MCI)and is a contemporary topic of research. MCI refers to the condition between normal aging and conditions in which people experience memory loss to a greater extent than one would expect for age, but they do not meet accepted criteria for clinically probable mild dementia. Consequently, this condition has been recognized as suitable for possible cognitive based intervention and therapy.
There are several useful rating scales available to access and characterise research participants along a continuum from normal aging through various stages of dementia, but do not necessarily coincide with the clinically relevant conditions of normal aging, MCI and mild dementia. Scales typically describe a continuum from normal (1) through to normal with questionable cognitive impairment (2), mild dementia (3) and more severe stages of dementia (4 – 7), within this rating scale subjects with mild cognitive impairment score either 2 or 3. The differentiation between normal functioning and mild impairment is an important area of research for cognitive psychologists, with the notion of normal aging and the associated cognitive impairments can be suppressed by intervention. Indeed, the notion of successful aging is a process of minimal cognitive impairment.
The lexical decision task (LDT) is a procedure commonly used in cognitive psychology and psycholinguistic experiments and a useful procedure for examining mild impairments in semantic memory. The LDT is commonly used to study the characteristics of the internal lexicon, where participants are required to classify visual stimuli as words or non-words as quickly and accurately as possible, thus analysis is based on the reaction times and, secondarily, the error rates. Whaley (1978) and Gordon (1983) proposed one of the strongest predictors in the lexical decision task is word frequency. This means words that are used most often in the English language are more likely to be recognised as words. It would appear the difference in response time required to respond to high versus low frequency words implies that people making a lexicon decision are influenced by their experience with the lexicon, and greater experience leads to faster decisions. Lexicon decisions are also faster for words having two or more meanings homographs versus non-homographs, implying that word frequency affects the order of retrieving stored words in long-term memory, and that more replicas of homographs than of non-homographs are stored in long term memory. Lexicon decision response times differ when participants are required to judge that a letter string (e.g. HOUSE) is a word and that it belongs to a prespecified semantic category – for a relatively small category (e.g. buildings), the latter semantic decision was significantly faster than the prior lexical decision, however, for a relatively large category (e.g. structures), the latter semantic decision was significantly slower than the prior lexical decision. This implies that semantic decision could involve a search through words stored in the semantic category, but that the lexical decision did not entail such a search process amongst the set of all words in memory (see; Meyer & Schvaneveldt, 1971; Rubenstein, Garfield & Millikan, 1970).
Meyer and Schvaneveldt (1971) demonstrated the positive effect priming has upon participant’s reaction times. Two strings of letters were presented simultaneously on each trial. Stimuli were arranged horizontally in a visual display with one string of letters positioned above the other. Stimulus presentations were paired combinations of either non-words (PABLE – REAB), a word/nonword (KNIFE – SMUKE) or words. Fifty percent of the paired words were commonly associated (BREAD-BUTTER; DOCTOR-NURSE) and fifty percent were non-associated (BREAD-NURSE; DOCTOR-BUTTER). Participants responded ‘no’ Exp 1 and ‘same’ Exp 2 if both strings of letters were words, and ‘no’ and ‘different’ respectively, otherwise. Findings showed that reaction time for yes and same responses was increased for associated words versus non-associated word pairs. Same responses were slowest for pairs of nonwords. No responses were quicker when the top letter string was a non-word, whereas different responses were faster when the top string was a word. The implications for those studying sematic memory are that stimulus items are processed serially, facilitation occurs in accessing stored information about associated words and that neural excitation in memory might be responsible for the associated effect. (also see; Schvaneveldt & Meyer 1973).
Research from Glisky (1997) has implied increased age leads to lower levels of performance in cognitive functioning. The institute also suggests older adults show significant deficits in tasks that involve manipulation and re-organization. These tasks include problem-solving and decision making. A quote from Plassman (1995) states “cognitive abilities remain stable throughout adult life until around age 60”. The present study is within a subject’s pre-intervention and post-intervention repeated measures design. At phase 1, participants over the age of 60 randomly selected from the normal population will complete a Global Deterioration Scale (GDS) and complete an experiment using the lexicon-decision task to assess fundamental memory process and lexical efficiency. At Phase 2, the same participants will engage in a cognitive based intervention that consists of a series of crossword puzzles over a period of two weeks. At phase 3, participants will repeat the lexicon-decision task to further assess semantic memory and lexical efficiency.
- Brief description of methods and measurements
At phase 1, participants over the age of 60 randomly selected from the normal population will complete a Global Deterioration Scale (GDS) and then participate in an experiment using the lexicon-decision. The experiment will use the original Meyer and Schvaneveldt (1971) lexicon decision paradigm. The lexicon decision task will be programmed in SuperLab software. Word pairs will be displayed on the computer screen and participants must decide if both two letter strings revealed are words or non-words. The task will include 1) pairs of words which are either semantically related (BREAD-BUTTER) or words which are not semantically related such as (BREAD-DOCTOR); 24 pairs of associated words (BREAD-BUTER) and 24 pairs of non-associated words (BREAD-CONCRETE). 2) Pairs of nonwords such as (EULG). There will be a total number of 16 non-word pairs (ELUG-TEEHS), 32 word/nonword pairs (BREAD-TSAOT). At the beginning of each trial a small fixation box will appear, after 1000 milliseconds stimuli will appear in the box, one letter string centred above the other. The participants must then decide whether the stimulus type is the same or different, both words versus nonwords respectively. The participants will select the appropriate key on the keyboard. The participant’s reaction times and correct response versus error rates will be collected and stored by SuperLab software. At Phase 2, the same participants will engage in a cognitive based intervention that consists of a workbook consisting of series of crossword puzzles to be completed over a period of two weeks (1 hour per night). At phase 3, participants will repeat the lexicon-decision task to test for possible improvements in semantic memory and lexical efficiency.
4. Participants: recruitment methods, number, age, sex, exclusion/inclusion criteria
The recruitment method for this study is opportunity sampling. This means the participants selected for the experiment are the most easily and readily available during the time of the study. The study will use both male and female participants who are aged 60 and over. The total number of participants required for this study is 12 and certain criteria must be met before selection. Firstly, participants who want to partake in this study must have English as a first language. Secondly, the participants must not be a habitual user of brain training activities such as crosswords or Sudoku. The third and final requirement is participants must not have a diagnosis of a brain disorder such as Alzheimer’s or a disorder which effects the ability to interpret words such as dyslexia.
5. Consent and participant information arrangements, debriefing.
Before commencing the study, all participants will be required to agree to take part in the study. Agreeing to take part in the study means the participants have understood what the study involves and the rights available. For the participants to give informed consent, a tick must be put in the “yes” box on the consent form. If the participants fail to tick the “yes” box then the participants will not be able to take part in the study. The informed consent letter will include a brief description of the research and what the study aims to investigate. It will also notify the participants that withdrawal from the study is allowed at any point of the research, even after the research has concluded. The research will also remind the participants that their agreement to take part is of a voluntary basis. Furthermore, the form will include details of the researcher and the supervisor of the study. After the study has ended the participants will be given a debriefing form which will reiterate what the informed consent form listed.
Please attach all intended information and consent forms, and where possible, outline interview schedules, experimental stimuli, questionnaires, as appendices at the end of this form.
6. A clear but concise statement of the ethical considerations raised by the project and how you intend to deal with them. If your proposed research involves any of the ‘special groups’ listed in Q12 on the previous page, please present a clear justification for this, addressing the points raised in the guidance notes.
Harm/risk:
The study will not contain words/ non-words which could cause offence, such as the use of foul language or psychologically damaging words which relate to hurtful events. If participants feel as though they are being subjected to harm, they will be informed that they can withdraw from the study at any time even after the study has concluded. Furthermore, if participants feel distressed whilst completing the crossword then withdrawal from the puzzle is also allowed. This can either be in the form of a time out or withdrawal completely if the stress is too much.
Confidentiality:
All participants’ information will be kept private and no personal details shall be revealed. All participants will be referred to in the form of letters such as “participant A”. This allows the participants to be identified and mentioned without names being revealed. In addition to this, the informed consent letter shall only contain a tick box so that participants do not have to sign using their signature. This makes sure that participant’s names cannot be identified.
Informed Consent Letter
Thank you for agreeing to take part in this research. Before being able to partake, it is important you are aware of what the study entails and the rights you have as a participant. Once you have been given the appropriate information, it is your decision as to whether you partake in study. To give your full informed consent, you must have an understanding of the following:
Aims of project:
The aim of this project is to test the effectiveness of a cognitive based intervention on semantic memory and word retrieval operations in adults aged 60 years and over with Mild non-clinical Cognitive Impairment (MCI). This dissertation aims to find out if this type of intervention would be the best suited method at slowing down the progression of Alzheimer’s Disease (AD) in those who have Mild Cognitive Impairment (MCI).
The Task
The task involves “priming” words with words which are semantically related in order to see if this has an effect on the person’s ability to recognise those words as words. An example of this is “priming” the word “doctor” with the word “nurse”. Both these words are related as they are similar professions. Similar words are stored more closely together in the brain and are thought to trigger a quicker response. Words which are not related such as “doctor” and “concrete” are stored much further away in the brain, which is thought to make it much harder for people to recognise these words as words, as it takes longer for a decision to be made. The reason why this project focuses on the over 60’s is after a certain age, it is suggested that ageing leads to a decline in cognitive functioning and the ability to decision make. The findings from this study aim to see if cognitive interventions facilitate improvements in memory and lexical efficiency in older participants with Mild non-clinical Cognitive Impairment (MCI).
Stages of Task and Duration
At phase 1 of the experiment, participant’s aged 60 years and over will be selected from the population using a convenience sample. All the participants will be required to complete a Global Deterioration Scale (GDS) which identifies the impairment. Participants who meet this criteria will be able to partake in the Lexical Decision Task (LDT). The Task will use the original Meyer and Schvaneveldt (1971) paradigm and will be programmed in the software known as SuperLab5. All the stimuli will be displayed on a computer screen leaving the participants to decide if both two letter strings revealed are words or nonwords. The task will include 24 pairs of words which are semantically related (BREAD-BUTTER), 24 pairs which are not semantically related (BREAD-CONCRETE) and 16 pairs of nonword pairs (TSOAST-ELUG). 32 pairs of word and nonword pairs will also be included (BREAD-ELUG). At the beginning of each trial a small fixation box will appear, after 1000 milliseconds (1 second) stimuli will appear in the box, one letter string centred above the other. The participants must decide if the stimulus type is the same or different, both words vs nonwords respectively. The participants must select the appropriate key on the keyboard to give an answer. The reaction times and error rates will be collected and stored in SuperLab5.
At phase 2 of the experiment, participants will be required to engage in a cognitive based intervention that consists of a workbook containing a series of crossword puzzles. These puzzles should be completed over a period of two weeks, 1 hour per day.
At phase 3 of the experiment, the participants will be required to repeat the Lexical Decision Task (LDT) previously underwent to test for a possible improvement in semantic memory and lexical efficiency
Requirements (Inclusion/Exclusion Criteria)
1) Must have English as a first language as this experiment uses words which are a part of the English vocabulary and therefore those who grew up speaking another language may be disadvantaged
2) Must be aged 60 + and have a diagnosis of Mild non-clinical Cognitive Impairment (MCI) (based on Global Deterioration Scale score)
3) Must not have a learning difficulty/ disability which effects the person’s ability to understand/ interpret words. An example of this is dyslexia
4) Must not have Alzheimer’s Disease (AD), as again this effects the person ability to understand/ remember words
5) Must not regularly partake in mentally or socially stimulating activities such as crosswords or sudoku puzzles as those who are accustomed to these types of puzzles may show no improvement in the post intervention
6) The final requirement relates to on the day of the experiment, participants are required to no consume any stimulating drinks such as coffee or energy drinks as these could influence the results.
Confidentiality
All the results obtained from this experiment will be kept confidential and will not be discussed with other participants, anybody who agrees to take part will be labelled from 1-12 to differentiate between each participant.
Right to Withdraw
All the participants are able to withdraw from the study at any time during and after the experiment has ended. Anybody who expresses a desire to withdraw will not have any data published in the final paper.
Protection from harm
Participants will not be subjected to harm as the experiment does not use offence or foul language. If participants feel harmed in anyway, the option of withdrawal is available.
After being made aware of what the study entails and your rights as a participant, do you still wish to continue?
Debriefing Form
Thank you for taking the time to complete this study. The purpose of this project was to find out if a cognitive based intervention affects a person’s semantic memory and lexical efficiency. The task used to gather data for this research was called a Lexical Decision Task (LDT). As a participant, you were required to decide if the words displayed on the screen were real words or nonwords. All the data was based around the reaction times and error rates to the stimuli presented. You were required to repeat the same Lexical Decision Task (LDT) two weeks later after completing a series of crossword puzzles that were handed to you, in the form of a workbook. These puzzles were expected to be completed for 1 hour per day. After the completion of both Lexical Decision Tasks (LDT) the results were compared to see if the cognitive based intervention has facilitated a speeded response to the stimuli. This type of response would indicate an improvement in semantic memory processing and lexical efficiency.
Thanks again for taking part
If you have any questions regarding this research, either contact myself or my supervisor using the contact details below
Cite This Work
To export a reference to this article please select a referencing stye below:
Related Services
View all
Related Content
All TagsContent relating to: "Neurology"
Neurology is the specialist branch of medicine that deals with the treatment of disorders of the nervous system. This means that neurologists concern themselves with issues affecting the brain, the nerves, and the spinal cord.
Related Articles
DMCA / Removal Request
If you are the original writer of this dissertation and no longer wish to have your work published on the UKDiss.com website then please: