Maura Mitrushina

Effect of repeated administration of a neuropsychological battery in the elderly.

Our study explored the magnitude of practice effect in repeated administration of NP measures that tap different cognitive domains in normal elderly subjects (N = 122) between ages 57 and 85, who were evaluated over three annual testing probes. Results revealed that WAIS-R PIQ, serial recall of words, WMS visual memory, and memory for logical passages (immediate and delayed) are likely to improve on the retest due to practice effect in individuals below age 75, whereas test-retest changes in older people show a different pattern. Implications of age-specific changes on retest for differential diagnosis of dementia in clinical practice were considered.

Reliability and validity of the mini-mental state exam in neurologically intact elderly

Reliability and validity of MMSE were explored in a sample of 122 healthy, community-residing elderly volunteers between the ages of 57 and 85, who were tested with a battery of neuropsychological tests over three annual probes. Test-retest reliability ranged between .45 and .50 over a 1-year interval and was .38 over a 2-year period. Change on the MMSE of more than 5 points over a 2-year period was associated with a neurological disorder. Significant correlations were found with many neuropsychological measures, especially with a measure of verbal learning.

The relationship between age and cognitive impairment in HIV-1 infection : findings from the Multicenter AIDS Cohort Study and a clinical cohort

Article abstract–Previous studies have identified age as a risk factor for many neurologic disorders, and a “cerebral reserve” factor has been postulated to explain these findings. This study examined whether age represents a risk factor for HIV-1-related neuropsychological dysfunction. Subjects for study 1 were primarily asymptomatic seropositive (n = 1,066) and seronegative (n = 1,004) nonelderly male community volunteers who completed neuropsychological and reaction time measures. Data analyses revealed a significant effect for age on reaction time and timed neuropsychological measures, but no interaction between age and serostatus. Study 2, employing a similar neuropsychological battery, consisted of 76 seropositive men (29 over age 55) recruited from community outpatient clinics and 47 seronegative controls. We found serostatus and age to have main effects on a number of measures, but a trend for an effect of age-serostatus interaction on only one measure.

Left-handedness and old age: Do left-handers die earlier?

Data are presented on the prevalence of current left-handedness and prior left-handedness (switched) in 2787 subjects from 21 to 101 years of age. In addition, data on sex differences, familial sinistrality, hand posture when writing, and education were recorded. Two hypotheses were tested. The elimination hypothesis states that reduced frequency of left-handers in old age is due to reduced longevity. The modification hypothesis states that differences in the number of left-handers between older and younger persons are due to changing patterns of social norms. The results showed a decreasing prevalence of left-handedness across the age span, with 15.22% in the youngest group (21-30 years), but only 1.67% in subjects older than 80 years. There was however a corresponding increase in the number of subjects who had switched hand for writing, 2.69% in the youngest group to 6.75% in subjects 80 years and above. This supports the modification hypothesis and questions the elimination hypothesis. However, the mean percent score was still lower in subjects above compared to below age 40 after correction for hand switching. Thus, although changes in social norms towards left-handers seem to be the most likely explanation, we have not empirically disproved the elimination hypothesis.

Neuropsychological processes associated with normal aging

This study reports cross‐sectional data on 156 normal older adults, aged 57–85 years old, who were enrolled in a study that addressed the neuropsychological processes associated with normal aging. The results based on a factor analysis of 12 key neuropsychological measures assessing a broad range of cognitive domains revealed three primary factors: (a) a Verbal Cognitive/Verbal Memory factor; (b) a Nonverbal Cognitive/Nonverbal Memory factor; and (c) a timed, Speed of Processing factor. This analysis accounted for 62% of the overall variance. Univariate regression analyses revealed that, consistent with prior research, tests comprising the third factor (speed of processing) were the most sensitive to changes associated with normal aging.

Emotional sequelae of stroke: A longitudinal perspective

This study investigated emotional change following stroke at acute (2-week), 2-month, and 6-month time intervals. Five dimensions of emotional functioning were examined in a sample of 19 stroke subjects: indifference, inappropriateness, depression, mania, and pragnosia (a defect in the pragmatics of social communicative style). Results showed that, at the 2-month point, differential recovery rates become apparent depending on hemispheric side of the stroke lesion. Increased indifference, inappropriateness, and depression appear to account for these results and suggest a slower rate of recovery on these variables in the left hemisphere group (LH n = 9) compared to the right (RH n = 10). Results further indicate that, at the 6-month point, emotional functioning in RH subjects appears to worsen. In contrast, emotional recovery in LH subjects seems to stabilize at this time. Clinical implications of these findings in terms of type and timing of intervention are discussed.

Heterogeneity of cognitive profiles in normal aging: implications for early manifestations of Alzheimer's disease

This study explores the presence of homogeneous subgroups among 156 normal elderly subjects based on their performance on a battery of neuropsychological tests. Subjects ranged in age between 57 and 85 years and included 62 males and 94 females with a mean age 70.7 years, mean education 14.1 years, and mean Full Scale IQ of 117.2. Six clusters were extracted, three of which are likely to represent preclinical stages of the dementing process with distinct patterns of cognitive deficits. The results are discussed in light of different models of cognitive deterioration in DAT.

A comparison of cognitive profiles in schizophrenia and other psychiatric disorders

This study compared patients across 5 psychiatric diagnostic groups: Depression, Mania, Schizophrenia, Schizoaffective Disorder, and Psychosis NOS, all of whom are psychotic. Differences in overall cognitive profiles and in dysfunctional memory mechanisms, as well as the effect of psychosis on cognitive functioning were explored using the Neurobehavioral Cognitive Status Examination (NCSE), a brief screening instrument. Results indicated pronounced deficit in memory and abstract reasoning associated with schizophrenic illness, which is not secondary to psychosis and points to localized brain dysfunction. Both encoding and postencoding memory mechanisms were affected. Results support a hypothesis of progressive dysfunction associated with the severity and chronicity of the illness. Implications of findings in aiding diagnostic determination, patient management and rehabilitation are discussed.

Performance on motor tasks as an indication of increased behavioral asymmetry with advancing age.

Age-related asymmetrical functional decline was tested on a sample of 64 right-handed volunteers between 60 and 64 years of age who were free from neurological illnesses and physical handicaps. Increase in functional asymmetry was explored by examining performance indexes for each hand and superiority of the dominant hand on motor tasks of different complexities: the Finger Tapping Test, the Grooved Pegboard Test, and the Pin Test. Our study revealed an increase in superiority of the right hand with age on a highly demanding task (Pin Test). This finding is discussed in light of the hypothesis of a decline in callosal functioning with age and the alternative hypothesis of a greater vulnerability of the right hemisphere in the elderly.

Correlates of self-rated health in the elderly

The relationship between self-rated health status and age group, gender, self-reported number of physical symptoms, functional capacity and level of activity was explored in a group of 133 elderly subjects ranging in age from 57 to 85 years. Self-rating of health was found to be a useful measure of health status, which is highly related to a number of physical symptoms and evidence of disruption in everyday functioning due to health problems. Women’s overall ratings of health were interpreted as reflecting a more optimistic appraisal of their self-ratings of health. (Aging 3: 73-77,1991)