Acquisition and retention of categorized material in normal aging and senile dementia

A Systematic Review of Antidepressants and Psychotherapy Commonly Used in the Treatment of Late Life Depression for Their Effects on Cognition

Cognitive dysfunction is common in late life depression (LLD) and is a major risk factor for dementia. Recent studies show limited improvement in cognition with commonly employed treatments for LLD, contradicting the notion that cognition "returns to normal" with treatment. However, findings differ with the treatments used. The aim of this study is to perform a systematic review of studies of antidepressants and psychotherapies commonly employed in LLD to determine their effects on cognition, particularly processing speed, memory, and executive function. We searched for trials of acute phase treatment, in nondemented individuals 60 years and older with unipolar nonpsychotic Major Depressive Disorder, that assessed cognitive performance with neuropsychological tests before and after treatment. We compared the magnitude of change in cognition by examining within group effect sizes. Six antidepressant trials and two psychotherapy trials (both using Problem Solving Therapy)(PST) provided relatively comparable data that allowed for quantitative comparison. Nine other antidepressant trials provided descriptive findings. Sertraline and vortioxetine had significant positive effects on processing speed and memory. Duloxetine had significant effects on memory. The most selective SRIs-citalopram and escitalopram-had minimal effects on cognition and citalopram had adverse effects in depression nonresponders. PST had modest effects on processing speed and no effect on memory. Effects of practice and improvement in depression on cognition are examined. In all but one study, cognition was a secondary outcome and various quality indicators (e.g. blinding cognitive assessment to treatment) were often not reported. As a consequence, these findings must be considered preliminary.

Effects of Lutein and Astaxanthin Intake on the Improvement of Cognitive Functions among Healthy Adults: A Systematic Review of Randomized Controlled Trials

Background: Fruits and vegetables are generally rich in antioxidants such as carotenoids. Consumption of carotenoids is expected to have benefits on cognitive functions in humans. However, previous randomized controlled trials (RCT) using carotenoids have reported inconsistent results. Therefore, this systematic review (SR) aimed to summarize the effect of carotenoid intake on cognitive functions in humans. Method: PubMed, Cochrane Library, Web of Science, and PsychoINFO were searched for research papers on carotenoid intake with the criteria that 1) oral carotenoid intake was evaluated using RCTs, 2) participants were healthy young, middle-aged, or older, and 3) cognitive functions were measured using RCTs. Results: Five studies using lutein and two studies using astaxanthin met the inclusion criteria. Consumption of lutein and its isomer showed consistent results in selective improvement of visual episodic memory in young and middle-aged adults while inhibition was observed in middle-aged and older adults. One of the two included astaxanthin studies reported a significant improvement of verbal episodic memory performance in middle-aged adults. Conclusion: This SR showed that the 10 mg lutein per day for twelve months can lead to improvement of cognitive functions. Due to the small number of studies, it is difficult to conclude whether astaxanthin would have a positive effect on cognitive functions.

Two Year Outcomes, Cognitive and Behavioral Markers of Decline in Healthy, Cognitively Normal Older Persons with Global Deterioration Scale Stage 2 (Subjective Cognitive Decline with Impairment)

BACKGROUND

Little is known with respect to behavioral markers of subjective cognitive decline (SCD), a condition initially described in association with Global Deterioration Scale (GDS) stage 2.

OBJECTIVE

Two-year interval behavioral markers were investigated herein.

METHODS

Subjects from a published 7-year outcome study of GDS stage 2 subjects were selected. This study had demonstrated a hazard ratio of 4.5 for progression of GDS stage 2, in comparison with GDS stage 1 (no subjective or objective cognitive decline) subjects, after controlling for demographic and temporal variables. Because GDS 2 subjects have previously demonstrated impairment in comparison with healthy persons free of complaints, we herein suggest the terminology "SCD(I)" for these persons. 98 SCD(I) persons, 63 women and 35 men, mean baseline age, 67.12±8.75 years, with a mean educational background of 15.55±2.60 years, and mean baseline MMSE scores of 28.9±1.24 were followed for 2.13±0.30 years.

RESULTS

Observed annual decline on the GDS was 6.701% per annum, very close to a 1986 published estimate. At follow up, the MMSE, and 7 of 8 psychometric tests did not decline significantly. Of 21 Hamilton Depression Scale items, 2 improved and the remainder were unchanged. Anxieties declined from multiple perspectives. The Brief Cognitive Rating Scale (BCRS) declined significantly (p < 0.001), with component declines in Remote memory (p < 0.01), and Functioning/self-care (p = 0.01).

CONCLUSION

SCD(I) persons decline at an annual rate of approximately 6.7% /year from several recent studies. The BCRS assessments and the Digit Symbol Substitution Test can be sensitive measures for future studies of progression mitigation.

A possible role for lutein and zeaxanthin in cognitive function in the elderly

Epidemiologic studies suggest that dietary lutein and zeaxanthin may be of benefit in maintaining cognitive health. Among the carotenoids, lutein and zeaxanthin are the only two that cross the blood-retina barrier to form macular pigment (MP) in the eye. They also preferentially accumulate in the human brain. Lutein and zeaxanthin in macula from nonhuman primates were found to be significantly correlated with their concentrations in matched brain tissue. Therefore, MP can be used as a biomarker of lutein and zeaxanthin in primate brain tissue. This is of interest given that a significant correlation was found between MP density and global cognitive function in healthy older adults. An examination of a relation between cognition and lutein and zeaxanthin concentrations in the brain tissue of decedents from a population-based study in centenarians found that zeaxanthin concentrations in brain tissue were significantly related to antemortem measures of global cognitive function, memory retention, verbal fluency, and dementia severity after adjustment for age, sex, education, hypertension, and diabetes. In univariate analyses, lutein was related to recall and verbal fluency, but the strength of the associations was attenuated with adjustment for covariates. However, lutein concentrations in the brain were significantly lower in individuals with mild cognitive impairment than in those with normal cognitive function. Last, in a 4-mo, double-blinded, placebo-controlled trial in older women that involved lutein supplementation (12 mg/d), alone or in combination with DHA (800 mg/d), verbal fluency scores improved significantly in the DHA, lutein, and combined-treatment groups. Memory scores and rate of learning improved significantly in the combined-treatment group, who also showed a trend toward more efficient learning. When all of these observations are taken into consideration, the idea that lutein and zeaxanthin can influence cognitive function in older adults warrants further study.

Relationship between event-related potentials and frontal-subcortical dysfunction in Parkinson's disease

Cognitive impairment in Parkinson's disease (PD) has been determined to be due to the interruption of frontal-subcortical neural circuits. To evaluate which kind of frontal-subcortical dysfunction may be present and the relationship of this dysfunction with P300 in PD patients, non-demented PD patients and controls were rendered for comprehensive Frontal Test Battery and P300 assessments. PD patients manifested significantly with frontal dysfunction and revealed a good correlation between P300 and executive dysfunction. We conclude that PD patients may manifest with cognitive impairment related to frontal dysfunction, and P300 may be an indicator reflecting the evolution of dysexecutive syndrome.

Does antidepressant therapy improve cognition in elderly depressed patients?

OBJECTIVES

To analyze the effects of antidepressants on cognitive functioning in elderly depression.

METHODS

Data were pooled for elderly participants with major depression from two double-blind 12-week studies (n = 444) comparing sertraline to fluoxetine and to nortriptyline. A cognitive battery was performed pre-treatment and post-treatment that included the Shopping List Task (SLT), which quantifies short-term and long-term memory storage and retrieval, and the Digit Symbol Substitution Test (DSST), which measures visual tracking, motor performance, and coding.

RESULTS

Older age, male gender, higher systolic blood pressure, and higher illness severity were associated with lower performance on specific cognitive measures at baseline. For the entire group, improved depression and a lower anticholinergic side effect (dry mouth and constipation) severity were associated with statistically significant improvement in the SLT and DSST. The correlations between improvements in depression and improvement in tested cognitive function were highest for sertraline followed by nortriptyline and then fluoxetine.

CONCLUSIONS

Acute improvement in depression is associated with cognitive improvement as measured by the SLT and DSST. Prospective studies are warranted to study the effects of potential differences among antidepressant therapies on long-term cognitive outcomes in geriatric depression.

Analysis of probabilistic classification learning in patients with Parkinson's disease before and after pallidotomy surgery

This study examined the characteristics of probabilistic classification learning, a form of implicit learning previously shown to be impaired in patients with basal ganglia dysfunction (e.g., Parkinson's disease). In this task, subjects learn to predict the weather using associations that are formed gradually across many trials, because of the probabilistic nature of the cue-outcome relationships. Patients with Parkinson's disease, both before and after pallidotomy, and age-matched control subjects, exhibited evidence of probabilistic classification learning across 100 training trials. However, pallidotomy appears to hinder the learning of associations most implicit in nature (i.e., weakly associated cues). Although subjects were most sensitive to single-cue associations when learning the task, there is evidence that cue combinations contribute significantly to probability learning. The utility of multiple dependent measures is discussed.

Cortisol differentially affects memory in young and elderly men

Nine young and 11 elderly men participated in this placebo-controlled, double-blind, crossover study (0.5 mg/kg cortisol or intravenous placebo). Participants learned a word list before cortisol administration, and delayed recall was then tested. A 2nd word list was learned and recalled after drug administration. In addition, the Paragraph Recall Test and tests measuring working memory (Digit Span), attention (timed cancellation), and response inhibition (Stroop Color and Word Test) were administered at 2 time points after drug administration. Cortisol reduced recall from the word list learned before treatment in both groups but did not influence recall of the list learned after treatment. In contrast, Digit Span performance was decreased by cortisol in young but not elderly participants. The possibility that differential age-associated brain changes might underlie the present results is discussed.

Staged bilateral pallidotomy for treatment of Parkinson disease

OBJECT

Several investigators have described the motor benefits derived from performing unilateral stereotactic pallidotomy for the treatment of Parkinson disease (PD), but little is known about the efficacy and complication rates of bilateral procedures. The goal of this study was to assess both these factors in 12 patients.

METHODS

Eleven patients with medically intractable PD underwent staged bilateral pallidotomy and one patient underwent a simultaneous bilateral procedure. Unilateral pallidotomy resulted in an improvement in the patients' Unified Parkinson Disease Rating Scale (UPDRS) total scores and motor subscores, Hoehn and Yahr stages, and Schwab and England Activities of Daily Living scores. There were no complications. The second procedures were performed 5 to 25 months after the first, and nearly complete 3-month follow-up data are available for eight of these patients. Staged bilateral pallidotomy did result in further improvements in some symptoms, but the patients proved to be less responsive to levodopa. In contrast to outcomes of the initial unilateral pallidotomy, there were significant complications. One patient suffered an acute stroke, two patients suffered delayed infarctions of the internal capsule, four patients had mild-to-moderate worsening of speech and increased drooling, and one patient complained of worsening memory.

CONCLUSIONS

Bilateral pallidotomy results in modest benefits but is associated with an increased risk of complications.

Effects of age, education, and sex on response bias in a recognition task

This study examined age-related differences in decision criteria and the extent to which inconsistencies in earlier findings could be due to sampling artifacts, especially the underlying effects of educational level and sex. Male and female participants (N = 3,059) from 4 age groups (32, 42, 52, and 62 years) and a wide range of educational levels performed a word recognition task. Response bias was assessed with a nonparametric index derived from signal detection theory. The analyses revealed no age differences except for the most educated subjects, for whom increased age was associated with stricter decision criteria. Lower levels of education and men as compared with women were associated with a more conservative bias. Controlling for the level of sensitivity did not significantly change this pattern of results. This finding stresses the need for caution in generalizing age differences obtained from samples that are only partly representative or imbalanced with respect to education and sex.

The Frontal Lobe Score: part II: evaluation of its clinical validity

OBJECTIVE

To evaluate the ability of the Frontal Lobe Score (FLS) to differentiate patients with frontal lobe lesions from those with nonfrontal lesions and normal controls.

DESIGN

In a prospective, blind setup, the sensitivity and specificity of the Frontal Lobe Score was compared with the Wisconsin Card Sorting Test (WCST) and the Stroop Test.

PATIENTS

A sample of 108 subjects (26 patients with cerebral lesions confined to the frontal lobes, 28 patients with cerebral lesions without involvement of the frontal lobes, 31 patients with mixed frontal/nonfrontal lesions, 23 controls without cerebral lesions) was examined.

MEASURES

Frontal Lobe Score, Wisconsin Card Sorting Test, Stroop Test.

RESULTS

The Frontal Lobe Score detected pure frontal lesions with a sensitivity of 92.3%. It discriminated patients with frontal lesions from normal controls with a specificity of 100%; differentiation from patients with nonfrontal lesions was obtained with a specificity of 75.0%. For the WCST, sensitivity for detection of pure frontal lesions was 65.4%, while specificity was 60.9% compared with normal controls and 53.6% compared with nonfrontal lesions. The Stroop Test showed a sensitivity of 30.8%, a specificity compared with normal controls of 95.7% and compared with nonfrontal lesions of 92.9%.

CONCLUSION

The Frontal Lobe Score has clinical usefulness for screening of effects of frontal lobe damage superior to that of the WCST and the Stroop Test.

Comparative efficacy of sertraline vs. fluoxetine in patients age 70 or over with major depression

Using data from a larger 12-week clinical trial, the authors evaluated the comparative efficacy and safety of sertraline (n=42) and fluoxetine (n=33) in patients over age 70 with a diagnosis of major depressive disorder. Similar improvement on measures of depression, including remission of depressive symptoms, was evident, although significantly more sertraline-treated patients achieved a criterion clinical response. Significantly greater improvement for the sertraline group was apparent on the Digit Symbol Substitution Test, but not on two other measures of cognitive functioning. Although there was no difference in the rate of adverse events experienced, fluoxetine-treated patients lost significantly more body weight over the 12-week trial than did sertraline-treated patients, whereas the latter group exhibited significantly more "shaking. "

Adult age differences in semantic and episodic memory

In 2 experiments, performance was compared on memory tests taken by older and younger adults for information that had been rated as more memorable for older adults or more memorable for each age group by adults in that age group. In Experiment 1, semantic knowledge was tested by having the participants recognize or recall information from memory (e.g., name as many states as you can). The older adults performed significantly better; thus, hypotheses of superior knowledge and ease of retrieval of that knowledge for that age group were supported. In Experiment 2, lists of presidents and states were presented to the participants, followed by recognition and recall tests of episodic memory. The younger adults performed significantly better. The older adults studied familiar items on the lists for less time and made many more errors. Thus, the hypothesis of an encoding deficit influenced by item familiarity for older adults was supported.

The California Verbal Learning Test: psychometric characteristics and clinical application

The California Verbal Learning Test (CVLT) is a popular clinical and research test that claims to measure key constructs in cognitive psychology such as repetition learning, serial position effects, semantic organization, intrusions, and proactive interference. The psychometric characteristics of the CVLT are reviewed and related to the test's clinical utility. The utility of the CVLT is shown to be limited by its poor standardization and inflated norms. Further, the validity is limited because the CVLT uses multiple trials whereas the constructs it purports to measure are based on single-trial paradigms. The review proposes modifications to the CVLT and guidelines for its clinical use. It concludes that if the limitations of the CVLT are recognized, it can still make a useful contribution to the clinical assessment of verbal learning and memory.

A longitudinal study of cognitive function in elderly persons with subjective memory complaints

OBJECTIVE

To assess change in cognitive function in elderly individuals with subjective memory loss over a follow-up interval of more than 3 years.

DESIGN

Prospective cohort study.

SETTING

An outpatient research clinic in aging and dementia at a university hospital.

PARTICIPANTS

A convenience sample of 59 healthy, elderly individuals (mean age 68.7 years) with memory complaints but no clinically apparent cognitive dysfunction.

MEASUREMENTS

Participants were given a full diagnostic evaluation and were administered a neuropsychological test battery at baseline and follow-up. The cognitive assessment battery included 12 tests of recent memory, immediate memory, language function, visuospatial praxis, and psychomotor speed. Most of the tests had been established to be sensitive to cross-sectional age differences.

RESULTS

Of 59 subjects, 54 (91.5%) were successfully followed up an average of 3.4 years later. Between baseline and follow-up, two tests exhibited significant improvement, two tests exhibited significant decline, and the other eight were unaffected.

CONCLUSION

Elderly individuals with subjective perceptions of cognitive decrements who fail to provide clear evidence of cognitive impairment upon clinical interview are not at high risk for progressive cognitive deterioration over the subsequent 3- to 4-year interval.

Learning, forgetting, and retrieval of everyday material across the adult life span

Levels and rates of acquisition and amounts of forgetting of name-face associations and grocery list items were assessed in a sample of 1,921 normal participants that was divided into five age groups (i.e., 17-39, 40-49, 50-59, 60-69, and 70+). Retrieval was assessed via the consistent long-term retrieval score (CLTR) from the Grocery List Selective Reminding Test (GLSRT). Substantial linear age-associated declines in level of acquisition were noted for both name-face associations and grocery list items. There was a significant age-related drop in rate of acquisition of name-face associations. Remarkably, very little forgetting occurred over a 40-min delay at any age on either measure. There was a significant linear age-related decline in retrieval efficiency for grocery list items, when variance due to both level of acquisition and retention was removed. The nature of age-associated memory decline and its possible neuroanatomic correlates is discussed.

A two-year longitudinal study of cognitive function in normal aging and Alzheimer's disease

A group of 136 elderly subjects were administered a comprehensive neuropsychological test battery, which was readministered 2 years later. Among the 136 elderly subjects, 86 were assigned a diagnosis of probable Alzheimer's disease. An additional 33 young subjects were administered the assessment battery at baseline only. The normal elderly group exhibited no decline in cognitive test performance over the 2-year follow-up interval. Subjects with mild cognitive impairment, however, were as likely to deteriorate between baseline and follow-up as the more severely impaired subjects. The tests that exhibited longitudinal decline in the Alzheimer's disease patients constituted a subset of the tests that revealed cross-sectional deficits relative to the normal elderly. Differences in baseline cognitive test performance and in rate of cognitive deterioration were examined in relatively young versus relatively old Alzheimer's disease patients. Potential psychometric predictors of cognitive decline in the normal elderly were identified.

Differential validity of psychometric tests in dementia of the Alzheimer type

Forty-nine patients with a clinical diagnosis of probable dementia of the Alzheimer type underwent an extensive test battery designed to evaluate cognitive deficits according to NINCDS/ADRDA criteria. All patients demonstrated signs of impairment on this test battery. One day later, they were administered a second test battery that consisted of the Mini-Mental State Examination (MMS), the Alzheimer's Disease Assessment Scale (ADAS), the SKT test (SKT), and the Brief Cognitive Rating Scale (BCRS) to assess the construct validity, sensitivity, and possible shortcomings of these tests. A control group of 47 age-matched persons was administered the same test battery to allow a comparison with reference values from other studies. Due to the design of the study, values of controls and patients did not overlap. Intercorrelations in patients were above 0.65 (p < 0.05 after Bonferroni correction) for all four cognitive tests. The ADAS and BCRS appeared to document the whole course of the disease in patients studied. The best differentiation with the SKT test could be obtained in mild to moderate dementia; however, due to the test's construction, a floor effect demonstrated its limitations in the case of severe dementia. Results obtained with the MMSE indicated the contrary: a ceiling effect showed its lack of differentiation in mild dementia. Therefore, a combination of tests should be used in the evaluation of cognitive deficits in the course of dementia of the Alzheimer type.

Hypersensitivity to scopolamine in the elderly

Scopolamine hydrobromide, 0.43 mg/70 kg, was administered by subcutaneous injection to ten young and ten elderly subjects. A comprehensive neuropsychological test battery was used to assess the effects of scopolamine, as compared to placebo, on cognitive function. As previously reported for this group of young subjects, scopolamine significantly impaired performance on tests of recent memory and visuospatial praxis. The same effects were observed in the elderly subjects, but the magnitude of the effects was much larger. The scopolamine injections produced significant psychomotor slowing in the elderly, whereas higher doses of the drug are required to produce this effect in young subjects. In both young and old subjects scopolamine failed to affect immediate memory, language function, object sorting, and the frequency of intrusion errors (although trends toward an effect were more apparent in the elderly). Remote memory, tested in the elderly only, was also unaffected. The results suggest that scopolamine's cognitive effects are quantitatively more pronounced in elderly subjects than young subjects, but that they are qualitatively similar and do not constitute a valid model for the cognitive dysfunction associated with Alzheimer's disease.

Performance of four age groups of normal elderly on the Rey Auditory-Verbal Learning Test

This study explored effect of age on encoding, retention, and retrieval components of memory functioning in a sample of 156 healthy, elderly subjects between the ages of 57 and 85, partitioned into four age groups. Memory assessment was based on subjects' performance on the RAVLT, which consisted of five free-recall trials, recall after interference, and recognition trial. Significant group differences in recall were found on all five learning trials, whereas rates of learning, forgetting, and recognition did not differ for four age groups. In addition, primacy/recency effect was equally strong for all groups. Results suggest faulty retrieval mechanisms, whereas encoding and retention processes did not prove to be affected by aging.

Development of an "early" detection battery for dementia of the Alzheimer type

1. To develop a diagnostic battery sensitive to and specific for the early detection of Alzheimer disease (AD) dementia, the authors reviewed over 400 journal articles dealing with the diagnosis of A.D. or senile dementia and cognitive assessment in organic brain dysfunction and closed head injury. 2. We culled those studies that met our criteria for solid, reliable and statistically significant results and recommend the testing paradigms that most often produced good discrimination of mild AD dementia from normal senescence. 3. These include tests of language, verbal and non-verbal memory, perception, praxis, attention and reasoning. 4. The battery we assembled takes less than 1 hour to administer, requires no special equipment, and was designed as an early screen for use by psychologists, psychiatrists and other trained health care professionals; it is not intended for repeated administration, as in pharmacological or longitudinal studies.

Ability to register new information: a memory measure for the aged

Ability to register new information is a necessity for the maintenance of autonomy. Its measurement is especially critical with older patients to distinguish cognitive from other aging losses. This paper introduces the Aronson Shopping List, constructed to assess that ability. It describes a check on the test's reliability and an aspect of construct validity for its use. The subjects were 67 community volunteers aged 62 to 89 yr. Those aged 80 to 89 yr. required more training than members of the two preceding decades. Correlations of learning scores on the Aronson Shopping List with WAIS or WAIS--R subtests and prorated IQs were significant. Alternate form stability/reliability, checked after a mean interval of 11 mo. was .75. Assessing cognitive aging was discussed and related to memory.

Direct and indirect memory performance in patients with senile dementia

The performance of patients with a presumptive clinical diagnosis of Senile Dementia of the Alzheimer's Type was compared to that of a group of normal elderly on several memory and neuropsychological tasks. The patients were impaired on tasks of free and cued recall, but exhibited normal performance on a word-completion procedure similar to that used by Graf et al. (1984). Reasons for the discrepancy between these findings and those from related research which reports impairment of word completion in patients with Alzheimer's Disease are discussed. Of particular interest is the role the orientating task plays in word-completion performance.

Scopolamine effects on memory, language, visuospatial praxis and psychomotor speed

Scopolamine hydrobromide was administered by subcutaneous injection to 30 young subjects in a dose of 0.22 mg/70 kg, 0.43 mg/70 kg, or 0.65 mg/70 kg. Treatment effects were compared to placebo on an extensive cognitive assessment battery. Almost all tests in the battery had been previously administered to Alzheimer's disease patients and nondemented elderly subjects. Scopolamine produced deficits on tests of verbal recall, visuospatial recall, visual recognition memory, visuospatial praxis, visuoperceptual function, and psychomotor speed. Immediate memory, language function, object sorting, and frequency of intrusion errors were unaffected. The low dose of scopolamine produced some peripheral anticholinergic signs but did not affect the cognitive measures. The results support the conclusion reached in previous studies that the cognitive profile of scopolamine-injected young subjects is more similar to that of the nondemented elderly than to that of Alzheimer's disease patients.

Age-related sex differences in verbal memory

Verbal learning and memory were studied in 196 healthy men and women aged 40 to 89. The Rey Auditory Verbal Learning Task (RAVLT), a 15-word list, was presented over five trials followed by free recall after each trial. A recognition trial of 50 words subsequently was administered. A stepwise regression that examined the contributions of age, sex, and vocabulary on the five trials of the RAVLT showed that age and sex accounted for a significant portion of the variance on each trial. Vocabulary accounted for a significant portion of the variance only on trials 4 and 5. The recognition trial was not affected by age, sex, or vocabulary. Men had lower scores overall as compared to women. In the older age group (ages 66-89), this difference was significant on trials two through five. Possible mechanisms that may underlie these age-related sex differences in learning curves are discussed.

A visual recognition memory test for the assessment of cognitive function in aging and dementia

Young, non-demented elderly, and elderly demented subjects were administered a computerized visual recognition memory task. In the task, subjects were instructed to point out the new object from a group of objects whose number was progressively incremented. The test was subject-paced and made use of face-valid stimulus materials; it is closely comparable to tests developed for memory assessment in non-human primates that are sensitive to the effects of hippocampal ablation. The present task was found to elicit significant differences in performance between young and non-demented aged subjects, between the non-demented and demented elderly, and between demented subjects in the early and more advanced stages of senile dementia of the Alzheimer type (SDAT). In a discriminant analysis, the visual recognition memory test scores correctly classified 72.6% of the aged subjects and early SDAT patients. No significant difference in task performance was found between SDAT patients and demented patients with a significant cerebrovascular etiological component. Thus, although the task does not appear to be suitable for diagnostic purposes it would be useful for the assessment of treatment effects upon age-related cognitive dysfunction.

The link between memory performance, self-assessment, and affective status

To investigate the relationship between memory performance, self-assessment of memory, and affective status, 67 elderly females were administered a self-assessment memory questionnaire and multiple measures of affect and laboratory memory tet performance. Canonical correlations indicated that the memory performance scores were not related to the affective measures nor to the scales of self-assessed memory ability. Affective status and self-assessment of memory skill were related, suggesting that investigations of memory performance which rely on self-assessment should also measure affective status.

Effects of aging and dementia upon recent visuospatial memory

In two experiments, a total of 20 young normals, 29 elderly normals, and 76 elderly demented subjects were administered a computerized delayed visuospatial recall task. Subjects were instructed to remember which room of a 25-room house had a light on in the window. A choice reaction time task was interposed during the delay interval (0-120 seconds) between stimulus presentation and recall. The test was designed to be (1) face valid-relevant to the subjects' everyday lives, (2) sensitive and specific to the cognitive decline associated with senile dementia of the Alzheimer's type (SDAT), and (3) comparable to animal memory tests. Immediate recall of the spatial location of a single stimulus was found to be deficient in severely demented subjects only, and all groups exhibited a decline in recall accuracy with increasing delay intervals. This decline in recall accuracy was greatest in severely demented subjects, smaller in less demented subjects, still smaller in aged normals, and smallest in young normals. No significant forgetting of spatial location occurred between 30 and 120 seconds after stimulus presentation. Increasing stimulus number decreased recall accuracy in all groups and the elderly and elderly demented subjects were more sensitive to the increase in stimulus load than the young normals. Choice reaction time also proved sensitive to age and severity of dementia. Correlation analyses demonstrated that delayed spatial recall (as well as choice reaction time) is highly correlated with clinically evaluated global cognitive status, as well as with tests of verbal recall.(ABSTRACT TRUNCATED AT 250 WORDS)

Contextual effects upon text memory for young, aged-normal, and aged memory-impaired individuals

The purpose of the study was to assess contextual effects upon text memory for young, aged-normal, and aged memory-impaired individuals. Subjects read short passages which differed in their contextual relatedness to target sentences, and then recalled those target sentences. It was found that large differences distinguished the performance of the young from the elderly on the free recall task; that cueing aided the performance of the young and the elderly-normal more than the aged-impaired; and lastly, that no differences were found in recognition performance between young and aged normals whereas the performance of the aged-impaireds was significantly poorer than either the young or the aged-normal group. The results were interpreted in light of two hypothetical mechanisms; the first is labeled "normal" aging and the second, "pathological" aging.

Recall and recognition as diagnostic indices of Malignant Memory Loss in Senile Dementia: a Bayesian analysis

The Benign Senescent Forgetfulness of normal aging and the Malignant Memory Loss of Senile Dementia of the Alzheimer Type (SDAT) each have a distinct symptomatology, course, and prognosis. The purpose of this study was to evaluate the discriminative validity and relative predictive values of recall and recognition as diagnostic screening tests for the Malignant Memory Loss of SDAT. Thirty-six patients with mild to moderate SDAT and 40 normal aged controls were studied. Both recall and recognition showed good discriminative validity. However, analysis of recall and recognition by Bayes's Theorem revealed the relative predictive values as diagnostic screening instruments were 11% and 100% respectively. Thus, it was concluded that while both recall and recognition have discriminative validity under experimental conditions, a test of recognition is the preferred diagnostic instrument when screening for the Malignant Memory Loss of SDAT.

Contextual effects upon text memory for young, aged-normal, and aged memory-impaired individuals

The purpose of the study was to assess contextual effects upon text memory for young, aged-normal, and aged memory-impaired individuals. Subjects read short passages which differed in their contextual relatedness to target sentences, and then recalled those target sentences. It was found that large differences distinguished the performance of the young from the elderly on the free recall task; that cueing aided the performance of the young and the elderly-normal more than the aged-impaired; and lastly, that no differences were found in recognition performance between young and aged normals whereas the performance of the aged-impaireds was significantly poorer than either the young or the aged-normal group. The results were interpreted in light of two hypothetical mechanisms; the first is labeled "normal" aging and the second, "pathological" aging.