- Email: [email protected]
Metacognition in Alzheimer's disease
S120
Symposium S3-02: Neuropsychology
Background: In recent years, the focus of etiologic research for dementia, especially Alzheimer’s disease, has been in three main areas of investigation: neuro-imaging, neuro-genetics, and neuropsychological testing. In each of these areas, strong determinants of dementia have been identified. The strong associations of hippocampal atrophy, carriership of the APOE e4 allele, and memory performance with dementia and Alzheimer’s disease have been well-documented. The predictive utility of these has mostly been investigated in clinical samples. In this study, the predictive accuracy of these risk factors is assessed in a population-based setting and by using incident dementia cases. Methods: We used data from the Rotterdam Scan Study, which is a population-based cohort study with extensive data on risk factors and more than 10 years of follow-up for dementia, to investigate the predictive utility of hippocampal atrophy, carriership of APOE e4, and memory performance. We studied these risk factors separately and in combined models, and investigated the prediction at different follow-up time points. Results: These data show that though each of these risk factors strongly associates with dementia, their predictive utility beyond age and sex decreases with longer follow-up times, i.e. the utility for early prediction is limited. Conclusions: Based on these findings the implications for future research are discussed, both regarding etiology and prediction.
S3-01-05
DEPRESSION, STRESS, AND RISK FOR ALZHEIMER’S DISEASE
Mirjam I. Geerlings, University Medical Center Utrecht, Utrecht, Netherlands. Contact e-mail: [email protected] Background: It has frequently been hypothesized that depression can cause Alzheimer’s disease through hypersecretion of glucocorticoids, which would have deleterious effects on hippocampal structures. However, no large-scale studies in humans examined the direct relation between depression, hypothalamic-pituitary-adrenal (HPA) axis activity and hippocampal structures. The aim of this study was to examine the associations between depression, HPA-axis activity, and hippocampal and entorhinal cortex volumes. Methods: Cross-sectional analyses within 636 participants (mean age 6269 years, 81% male) from the Second Manifestation of ARTerial disease-Memory depression and aging (SMART-Medea) study, an ancillary study to the SMART-MR study, aimed to investigate brain changes associated with psychosocial stressors in patients with a history of atherosclerotic disease. Twelve-month diagnosis of major depressive disorder (MDD), early-onset depression (EOD) (<50 years) and late-onset depression (LOD) (50 years) were assessed. HPA-axis activity was measured with 6 saliva samples, collected at awakening and 30, 45 and 60 minutes thereafter, and at 10PM and 11PM. Suppression of the HPA-axis was defined as the cortisol value at awakening after ingestion of 0.5 mg dexamethasone at 11PM. Volumetric measurements of the hippocampus and entorhinal cortex were performed on a 3-dimensional FFE T1-weighted 1.5 Tesla MRI scan with isotropic voxels. Results: Regression models adjusted for demographics, vascular risk, antidepressant use and white matter lesions showed that MDD was not significantly associated with hippocampal or entorhinal cortex volumes. However, participants with EOD had significantly smaller hippocampal volumes than those never depressed, whereas participants with LOD had smaller entorhinal cortex volumes. Participants with higher evening cortisol levels and reduced suppression after dexamethasone had smaller hippocampal volumes. Higher evening cortisol levels were also associated with smaller right, but not left, entorhinal cortex volume. The cortisol awakening response was not significantly associated with hippocampal or entorhinal cortex volumes. Cortisol levels did not, however, explain the associations found between age of onset of depression with hippocampal or entorhinal cortex volumes. Conclusions: Although we found several associations between depression, HPA-axis activity, and hippocampal or entorhinal cortex volumes, from our studies it seems unlikely that hypersecretion of glucocorticoids is an explanation for the frequently observed association between depression, hippocampal atrophy, and Alzheimer’s disease.
S3-01-06
ATHEROSCLEROTIC DISEASE, ITS RISK FACTORS, AND DEMENTIA AMONG JAPANESEAMERICANS IN HAWAII
J. David Curb, University of Hawaii at Manoa, Honolulu, HI, USA. Contact e-mail: [email protected] Background: There is increasing evidence of an association between Alzheimer’s disease and atherosclerotic disease and it’s of risk factors. The nature of this association remains unclear. Methods: The Honolulu Heart Program (HHP) and the Hawaii-Asia Aging Study (HAAS), of 8006 Japanese-American men in Hawaii have provided a number of clues. Asian Americans (AA) comprise one of the fastest minority populations in the U.S. Japanese Americans in Hawaii are among the largest concentrations of AA and are among the longest lived subgroups in the U.S. and the world. They thus offer an ideal model in which to do longitudinal studies of chronic diseases in the elderly. The HHP was one of the earliest studies to do so. It began as part of the international NI-HON-SAN study(NHSS)in 1963. The NHSS was initiated to investigate observed significant differences and opposite trends in stroke and CHD rates among Japanese in Japan and Japanese migrants in Hawaii and California. Follow-up data indicates that risk factor-adjusted long-term non-cancer mortality rates for NI-HON-SAN men are substantially greater in Japan than in Hawaii. While the originally planned long term comparison of these populations was not continued, the HHP has continued for over 45 years, providing the opportunity for unparalleled long term longitudinal follow-up for atherosclerotic risk factors and their relationships to atherosclerosis related diseases. In 1991 the HAAS, a study of dementia and aging, was begun. This longitudinal study of combined with the HHPs mid to late life atherosclerotic risk factors has allowed longitudinal investigations of the relationships of these factors to vascular dementia and Alzheimer’s Disease in a manner not possible in most other studies. Results: Among the factors which have been investigated are anklebrachial index, hypertension and blood pressure, serum cholesterol, serum glucose and insulin, diabetes, and C-reactive protein. The results suggest most of the factors studied are related to risk of vascular dementia and Alzheimer’s disease. Conclusions: These studies have offered a number of clues regarding the relationship of atherosclerotic risk factors to vascular and Alzheimer’s dementias. Given the critical nature of these problems in an aging America, it is imperative that such investigations be continued. TUESDAY, JULY 13, 2010 SYMPOSIUM S3-02 NEUROPSYCHOLOGY S3-02-01
METACOGNITION IN ALZHEIMER’S DISEASE
Stephanie A. Cosentino, Columbia University Medical Center, New York, NY, USA. Contact e-mail: [email protected] Background: Awareness of memory loss varies remarkably across individuals with Alzheimer’s disease (AD), and comprises an important part of each person’s clinical presentation. Unlike disturbances to cognitive abilities such as memory and language, the etiology and nature of disrupted self awareness is poorly understood. Our limited knowledge regarding this clinical phenomenon may in part reflect constraints in the way that it has been measured. The overall purpose of this research is to deconstruct the clinical phenomenon of disordered awareness through use of objective metacognitive methodologies. In previous work, we introduced the potential utility of an objective metamemory task for quantifying and studying memory awareness in AD. The specific goals of the current work were to: 1) gain further evidence that our metamemory task captures day to day memory awareness in AD and is specifically self-referential; 2) determine whether there are conditions under which memory awareness can be facilitated; and 3) use cognitive testing to explore whether differential distribution of disease may influence metacognition in AD. Methods: Individuals with mild AD and non-demented elders underwent clinical interviews, cognitive testing, and metacognitive testing.
Symposium S3-02: Neuropsychology Results: In a replication of previous work, metamemory varied significantly as a function of clinically rated awareness in AD. Neither variable was related to dementia severity or verbal memory, but both correlated with nonverbal memory. Preliminary data suggest that requiring retrospective evaluation of memory responses, or providing feedback regarding memory accuracy can improve metamemory. Finally, in a second task validation study, metamemory was associated with another aspect of self-assessment (agency), and this relationship could not be accounted for by primary cognitive abilities or participant characteristics. Conclusions: Findings from individuals with AD and healthy elders converge to suggest that metamemory testing may offer an objective, reliable, and useful means of quantifying and studying memory awareness in AD. Manipulating the parameters of the metamemory test has the potential to provide detailed information about the nature of awareness deficits. Finally, preliminary data points to an association between memory awareness and nonverbal memory abilities in AD. The implications of this association for investigating the etiology of disrupted self-awareness will be discussed.
S3-02-02
A COGNITIVE PROFILE IN LESS THAN 5 MINUTES OF CLINICIAN TIME?
Peter W. Schofield, University of Newcastle, Newcastle, Australia. Contact e-mail: [email protected] Background: Cognitive testing is time consuming and this represents a major constraint in the development of cognitive screening instruments. Instruments that take longer than 5 minutes to administer have limited uptake in primary care practice. Computer-based screening instruments offer certain advantages but many require some supervision during the assessment. We adopted a novel approach to create a cognitive screening instrument that offers considerable scope of testing with good psychometric properties while still being very brief for the clinician. Methods: Our instrument, the Audio Recorded Cognitive Screen (ARCS), uses an audio device to administer selected neuropsychological tests to unsupervised individuals who write their responses in a special booklet for later scoring. A gentle preamble on the audio explains the testing procedure and even patients with dementia with Mini Mental Status Examination (MMSE) scores as low as 18/ 30 can be tested. Elements of the ARCS include a 12 word list learning task (modelled on the Hopkins Verbal Learning Test Revised), three verbal fluency measures (letter, category, and action), a clock drawing task, an object naming task (ten pictured items in the response booklet), a test of writing speed, and a two part psychomotor speed/executive function/attentional task unique to the ARCS. We have conducted extensive normative and validation studies and have characterised the psychometric properties of the ARCS as a screening instrument for detecting cognitive impairment and dementia. Results: Age, gender and education influence ARCS performance. ARCS tests are generally reliable and correlate well with corresponding conventional neuropsychological tests. Testing lasts 34 minutes, but only set up and scoring require a clinician (<5 minutes). Cognitive domain and global scores are scaled according to demographic characteristics (mean 100, SD 15). Receiver Operating Characteristic analyses confirmed the superiority of the ARCS over MMSE as a screen for mild dementia (AUC 0.98, 99%CI 0.95-1.00) or cognitive impairment (AUC 0.90, 99% CI 0.83-0.97). Conclusions: The ARCS has good validity and reliability, a sound normative base, and measures functioning in multiple cognitive domains while imposing minimal time demands upon the clinician. A profile encompassing five cognitive domains can be obtained in less than 5 minutes of clinician time.
S3-02-03
SERIAL POSITION ANALYSIS OF FREE RECALL AS EARLY MARKER OF COGNITIVE DECLINE
Mario Fioravanti, University of Rome Sapienza, Rome, Italy. Contact e-mail: [email protected] Background: Memorization is an active elaboration of information and encoding and organization during acquisition and retention are examples of
S121
these activities determining the efficiency of recall. Usually, memory is measured by the gross output (quantity and precision of recall) while processes underlying the output are not considered. Different processes can be able to achieve the same quantity of output depending on differences in stimuli and in conditions of presentation. Age and pathological factors could be determinant in which process is involved in memorization. Methods: The serial learning effect concerns the different probability of being recalled of stimuli presented as a unique series depending on the position in the series. This effect depends on internal to the series factors (familiarity, concreteness, imagery, semantic categorization, etc.) and external factors (speed of presentation, the length of acquisition/recall interval, etc.). In several studies with normal participants of different age and patients with Parkinson’s Disease, Chronic Cerebro-Vascular Disorders, and Alzheimer’s Dementia, the examination of those internal factors was carried out to examine their relationship with recall both in terms of gross output and of qualitative changes related to the encoding and organization. Results: The quantity of recalled items in a serial learning task remains constant across most of the life span of a normal person before presenting a decline once the aging process is more advanced. The invariant recall is produced by variant processes across age. Only later on, or with the presence of a degenerative disorder of the CNS, the quantity of recall shows its decline independently by the processes underlying it. Conclusions: A hierarchical organization is available to memory in order to acquire, organize, retain, and eventually reproduce stimuli. This hierarchy goes from the most complex, such as semantic categorization, to the simplest, such as serial position. The use of the top processes override the action of the lower processes of which the effects become evident only when the top process become attenuated. The modifications of the serial learning effect are relevant in examining which processes are involved in the memorization task for an in-depth diagnostic procedure to supplement the traditional gross output method (quantity of recall).
S3-02-04
LACK OF PRACTICE EFFECTS ON NEUROPSYCHOLOGICAL TESTS AS EARLY COGNITIVE MARKERS OF ALZHEIMER’S DISEASE?
Andreas U. Monsch, Memory Clinic, Department of Geriatrics, University Hospital, Basel, Switzerland. Contact e-mail: [email protected] Background: The reliable assessment of change from a previous cognitive functioning level is a prerequisite for determining the possible presence of neurodegenerative diseases such as Alzheimer’s disease (AD) and is a diagnostic sign of mild cognitive impairment (MCI). These criteria imply repeated neuropsychological testing. The purpose of our recent research was to assess the ability of different measures of cognitive change to detect very early AD. Methods: Study 1 investigated whether standardized change scores on the German version of the Consortium to Establish a Registry for Alzheimer’s Disease - Neuropsychological Assessment Battery (CERADNAB) are superior diagnostic markers of early AD than scores from a single time-point. 374 normal control subjects were assessed at baseline and an average of 2.4060.28 years later. Data from 95 patients with mild probable AD were collected at their first Memory Clinic testing and an average of 1.160.24 years later (Zehnder et al., 2008). Study 2 compared different longitudinal change measures in 366 cognitively healthy participants (237 men, 129 women) examined with a German version of the California Verbal Learning Test at baseline and 2 years later (Study 2; Blaesi et al., 2009). In both studies age, education, gender, and baseline performance were taken into account. Results: In Study 1, binary logistic regression analyses based on practice effects (T1-T0) revealed that the CERAD-NAB subtests MMSE, Word List-Learning, Word Lists 1-3, Word List-Savings, and Figures-Savings best distinguished NCs from AD patients; 93.3% NCs and 86.8% AD patients were correctly classified, yielding a 92.0% correct classification rate. Study 2 found marked practice effects in cognitively healthy individuals after 2 years. Normal ranges for change that control for practice effects and regression to the mean proved to be the best change index. This new method
Symposium S3-02: Neuropsychology
Background: In recent years, the focus of etiologic research for dementia, especially Alzheimer’s disease, has been in three main areas of investigation: neuro-imaging, neuro-genetics, and neuropsychological testing. In each of these areas, strong determinants of dementia have been identified. The strong associations of hippocampal atrophy, carriership of the APOE e4 allele, and memory performance with dementia and Alzheimer’s disease have been well-documented. The predictive utility of these has mostly been investigated in clinical samples. In this study, the predictive accuracy of these risk factors is assessed in a population-based setting and by using incident dementia cases. Methods: We used data from the Rotterdam Scan Study, which is a population-based cohort study with extensive data on risk factors and more than 10 years of follow-up for dementia, to investigate the predictive utility of hippocampal atrophy, carriership of APOE e4, and memory performance. We studied these risk factors separately and in combined models, and investigated the prediction at different follow-up time points. Results: These data show that though each of these risk factors strongly associates with dementia, their predictive utility beyond age and sex decreases with longer follow-up times, i.e. the utility for early prediction is limited. Conclusions: Based on these findings the implications for future research are discussed, both regarding etiology and prediction.
S3-01-05
DEPRESSION, STRESS, AND RISK FOR ALZHEIMER’S DISEASE
Mirjam I. Geerlings, University Medical Center Utrecht, Utrecht, Netherlands. Contact e-mail: [email protected] Background: It has frequently been hypothesized that depression can cause Alzheimer’s disease through hypersecretion of glucocorticoids, which would have deleterious effects on hippocampal structures. However, no large-scale studies in humans examined the direct relation between depression, hypothalamic-pituitary-adrenal (HPA) axis activity and hippocampal structures. The aim of this study was to examine the associations between depression, HPA-axis activity, and hippocampal and entorhinal cortex volumes. Methods: Cross-sectional analyses within 636 participants (mean age 6269 years, 81% male) from the Second Manifestation of ARTerial disease-Memory depression and aging (SMART-Medea) study, an ancillary study to the SMART-MR study, aimed to investigate brain changes associated with psychosocial stressors in patients with a history of atherosclerotic disease. Twelve-month diagnosis of major depressive disorder (MDD), early-onset depression (EOD) (<50 years) and late-onset depression (LOD) (50 years) were assessed. HPA-axis activity was measured with 6 saliva samples, collected at awakening and 30, 45 and 60 minutes thereafter, and at 10PM and 11PM. Suppression of the HPA-axis was defined as the cortisol value at awakening after ingestion of 0.5 mg dexamethasone at 11PM. Volumetric measurements of the hippocampus and entorhinal cortex were performed on a 3-dimensional FFE T1-weighted 1.5 Tesla MRI scan with isotropic voxels. Results: Regression models adjusted for demographics, vascular risk, antidepressant use and white matter lesions showed that MDD was not significantly associated with hippocampal or entorhinal cortex volumes. However, participants with EOD had significantly smaller hippocampal volumes than those never depressed, whereas participants with LOD had smaller entorhinal cortex volumes. Participants with higher evening cortisol levels and reduced suppression after dexamethasone had smaller hippocampal volumes. Higher evening cortisol levels were also associated with smaller right, but not left, entorhinal cortex volume. The cortisol awakening response was not significantly associated with hippocampal or entorhinal cortex volumes. Cortisol levels did not, however, explain the associations found between age of onset of depression with hippocampal or entorhinal cortex volumes. Conclusions: Although we found several associations between depression, HPA-axis activity, and hippocampal or entorhinal cortex volumes, from our studies it seems unlikely that hypersecretion of glucocorticoids is an explanation for the frequently observed association between depression, hippocampal atrophy, and Alzheimer’s disease.
S3-01-06
ATHEROSCLEROTIC DISEASE, ITS RISK FACTORS, AND DEMENTIA AMONG JAPANESEAMERICANS IN HAWAII
J. David Curb, University of Hawaii at Manoa, Honolulu, HI, USA. Contact e-mail: [email protected] Background: There is increasing evidence of an association between Alzheimer’s disease and atherosclerotic disease and it’s of risk factors. The nature of this association remains unclear. Methods: The Honolulu Heart Program (HHP) and the Hawaii-Asia Aging Study (HAAS), of 8006 Japanese-American men in Hawaii have provided a number of clues. Asian Americans (AA) comprise one of the fastest minority populations in the U.S. Japanese Americans in Hawaii are among the largest concentrations of AA and are among the longest lived subgroups in the U.S. and the world. They thus offer an ideal model in which to do longitudinal studies of chronic diseases in the elderly. The HHP was one of the earliest studies to do so. It began as part of the international NI-HON-SAN study(NHSS)in 1963. The NHSS was initiated to investigate observed significant differences and opposite trends in stroke and CHD rates among Japanese in Japan and Japanese migrants in Hawaii and California. Follow-up data indicates that risk factor-adjusted long-term non-cancer mortality rates for NI-HON-SAN men are substantially greater in Japan than in Hawaii. While the originally planned long term comparison of these populations was not continued, the HHP has continued for over 45 years, providing the opportunity for unparalleled long term longitudinal follow-up for atherosclerotic risk factors and their relationships to atherosclerosis related diseases. In 1991 the HAAS, a study of dementia and aging, was begun. This longitudinal study of combined with the HHPs mid to late life atherosclerotic risk factors has allowed longitudinal investigations of the relationships of these factors to vascular dementia and Alzheimer’s Disease in a manner not possible in most other studies. Results: Among the factors which have been investigated are anklebrachial index, hypertension and blood pressure, serum cholesterol, serum glucose and insulin, diabetes, and C-reactive protein. The results suggest most of the factors studied are related to risk of vascular dementia and Alzheimer’s disease. Conclusions: These studies have offered a number of clues regarding the relationship of atherosclerotic risk factors to vascular and Alzheimer’s dementias. Given the critical nature of these problems in an aging America, it is imperative that such investigations be continued. TUESDAY, JULY 13, 2010 SYMPOSIUM S3-02 NEUROPSYCHOLOGY S3-02-01
METACOGNITION IN ALZHEIMER’S DISEASE
Stephanie A. Cosentino, Columbia University Medical Center, New York, NY, USA. Contact e-mail: [email protected] Background: Awareness of memory loss varies remarkably across individuals with Alzheimer’s disease (AD), and comprises an important part of each person’s clinical presentation. Unlike disturbances to cognitive abilities such as memory and language, the etiology and nature of disrupted self awareness is poorly understood. Our limited knowledge regarding this clinical phenomenon may in part reflect constraints in the way that it has been measured. The overall purpose of this research is to deconstruct the clinical phenomenon of disordered awareness through use of objective metacognitive methodologies. In previous work, we introduced the potential utility of an objective metamemory task for quantifying and studying memory awareness in AD. The specific goals of the current work were to: 1) gain further evidence that our metamemory task captures day to day memory awareness in AD and is specifically self-referential; 2) determine whether there are conditions under which memory awareness can be facilitated; and 3) use cognitive testing to explore whether differential distribution of disease may influence metacognition in AD. Methods: Individuals with mild AD and non-demented elders underwent clinical interviews, cognitive testing, and metacognitive testing.
Symposium S3-02: Neuropsychology Results: In a replication of previous work, metamemory varied significantly as a function of clinically rated awareness in AD. Neither variable was related to dementia severity or verbal memory, but both correlated with nonverbal memory. Preliminary data suggest that requiring retrospective evaluation of memory responses, or providing feedback regarding memory accuracy can improve metamemory. Finally, in a second task validation study, metamemory was associated with another aspect of self-assessment (agency), and this relationship could not be accounted for by primary cognitive abilities or participant characteristics. Conclusions: Findings from individuals with AD and healthy elders converge to suggest that metamemory testing may offer an objective, reliable, and useful means of quantifying and studying memory awareness in AD. Manipulating the parameters of the metamemory test has the potential to provide detailed information about the nature of awareness deficits. Finally, preliminary data points to an association between memory awareness and nonverbal memory abilities in AD. The implications of this association for investigating the etiology of disrupted self-awareness will be discussed.
S3-02-02
A COGNITIVE PROFILE IN LESS THAN 5 MINUTES OF CLINICIAN TIME?
Peter W. Schofield, University of Newcastle, Newcastle, Australia. Contact e-mail: [email protected] Background: Cognitive testing is time consuming and this represents a major constraint in the development of cognitive screening instruments. Instruments that take longer than 5 minutes to administer have limited uptake in primary care practice. Computer-based screening instruments offer certain advantages but many require some supervision during the assessment. We adopted a novel approach to create a cognitive screening instrument that offers considerable scope of testing with good psychometric properties while still being very brief for the clinician. Methods: Our instrument, the Audio Recorded Cognitive Screen (ARCS), uses an audio device to administer selected neuropsychological tests to unsupervised individuals who write their responses in a special booklet for later scoring. A gentle preamble on the audio explains the testing procedure and even patients with dementia with Mini Mental Status Examination (MMSE) scores as low as 18/ 30 can be tested. Elements of the ARCS include a 12 word list learning task (modelled on the Hopkins Verbal Learning Test Revised), three verbal fluency measures (letter, category, and action), a clock drawing task, an object naming task (ten pictured items in the response booklet), a test of writing speed, and a two part psychomotor speed/executive function/attentional task unique to the ARCS. We have conducted extensive normative and validation studies and have characterised the psychometric properties of the ARCS as a screening instrument for detecting cognitive impairment and dementia. Results: Age, gender and education influence ARCS performance. ARCS tests are generally reliable and correlate well with corresponding conventional neuropsychological tests. Testing lasts 34 minutes, but only set up and scoring require a clinician (<5 minutes). Cognitive domain and global scores are scaled according to demographic characteristics (mean 100, SD 15). Receiver Operating Characteristic analyses confirmed the superiority of the ARCS over MMSE as a screen for mild dementia (AUC 0.98, 99%CI 0.95-1.00) or cognitive impairment (AUC 0.90, 99% CI 0.83-0.97). Conclusions: The ARCS has good validity and reliability, a sound normative base, and measures functioning in multiple cognitive domains while imposing minimal time demands upon the clinician. A profile encompassing five cognitive domains can be obtained in less than 5 minutes of clinician time.
S3-02-03
SERIAL POSITION ANALYSIS OF FREE RECALL AS EARLY MARKER OF COGNITIVE DECLINE
Mario Fioravanti, University of Rome Sapienza, Rome, Italy. Contact e-mail: [email protected] Background: Memorization is an active elaboration of information and encoding and organization during acquisition and retention are examples of
S121
these activities determining the efficiency of recall. Usually, memory is measured by the gross output (quantity and precision of recall) while processes underlying the output are not considered. Different processes can be able to achieve the same quantity of output depending on differences in stimuli and in conditions of presentation. Age and pathological factors could be determinant in which process is involved in memorization. Methods: The serial learning effect concerns the different probability of being recalled of stimuli presented as a unique series depending on the position in the series. This effect depends on internal to the series factors (familiarity, concreteness, imagery, semantic categorization, etc.) and external factors (speed of presentation, the length of acquisition/recall interval, etc.). In several studies with normal participants of different age and patients with Parkinson’s Disease, Chronic Cerebro-Vascular Disorders, and Alzheimer’s Dementia, the examination of those internal factors was carried out to examine their relationship with recall both in terms of gross output and of qualitative changes related to the encoding and organization. Results: The quantity of recalled items in a serial learning task remains constant across most of the life span of a normal person before presenting a decline once the aging process is more advanced. The invariant recall is produced by variant processes across age. Only later on, or with the presence of a degenerative disorder of the CNS, the quantity of recall shows its decline independently by the processes underlying it. Conclusions: A hierarchical organization is available to memory in order to acquire, organize, retain, and eventually reproduce stimuli. This hierarchy goes from the most complex, such as semantic categorization, to the simplest, such as serial position. The use of the top processes override the action of the lower processes of which the effects become evident only when the top process become attenuated. The modifications of the serial learning effect are relevant in examining which processes are involved in the memorization task for an in-depth diagnostic procedure to supplement the traditional gross output method (quantity of recall).
S3-02-04
LACK OF PRACTICE EFFECTS ON NEUROPSYCHOLOGICAL TESTS AS EARLY COGNITIVE MARKERS OF ALZHEIMER’S DISEASE?
Andreas U. Monsch, Memory Clinic, Department of Geriatrics, University Hospital, Basel, Switzerland. Contact e-mail: [email protected] Background: The reliable assessment of change from a previous cognitive functioning level is a prerequisite for determining the possible presence of neurodegenerative diseases such as Alzheimer’s disease (AD) and is a diagnostic sign of mild cognitive impairment (MCI). These criteria imply repeated neuropsychological testing. The purpose of our recent research was to assess the ability of different measures of cognitive change to detect very early AD. Methods: Study 1 investigated whether standardized change scores on the German version of the Consortium to Establish a Registry for Alzheimer’s Disease - Neuropsychological Assessment Battery (CERADNAB) are superior diagnostic markers of early AD than scores from a single time-point. 374 normal control subjects were assessed at baseline and an average of 2.4060.28 years later. Data from 95 patients with mild probable AD were collected at their first Memory Clinic testing and an average of 1.160.24 years later (Zehnder et al., 2008). Study 2 compared different longitudinal change measures in 366 cognitively healthy participants (237 men, 129 women) examined with a German version of the California Verbal Learning Test at baseline and 2 years later (Study 2; Blaesi et al., 2009). In both studies age, education, gender, and baseline performance were taken into account. Results: In Study 1, binary logistic regression analyses based on practice effects (T1-T0) revealed that the CERAD-NAB subtests MMSE, Word List-Learning, Word Lists 1-3, Word List-Savings, and Figures-Savings best distinguished NCs from AD patients; 93.3% NCs and 86.8% AD patients were correctly classified, yielding a 92.0% correct classification rate. Study 2 found marked practice effects in cognitively healthy individuals after 2 years. Normal ranges for change that control for practice effects and regression to the mean proved to be the best change index. This new method