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J A Yesavage

Publications and source records attributed to J A Yesavage.

At least 19 recordsLinked to original sources
PubMed2001

Rate of cognitive decline in AD is accelerated by the interleukin-1 alpha -889 *1 allele.

The reason for differences in rate of cognitive decline in AD is unknown. The interleukin-1 alpha (IL-1 alpha) -889 *2 allele is associated with increased risk for AD. Surprisingly, in a sample of 114 patients followed for an average of 3.8 years, individuals homozygous for the IL-1 alpha -889 *1 allele declined significantly more rapidly on the Mini-Mental State Examination than did others. There was no difference in rate of decline between patients with and without the APOE epsilon 4 allele. These results support the hypothesis that inflammation is important in the clinical course of AD.

Adult↗
PubMed2001

Relationship between variations in estradiol and progesterone levels across the menstrual cycle and human performance.

RATIONALE: Studies about whether or not the cognitive performance of women is influenced by changes in levels of sex steroid hormones across the menstrual cycle have produced ambiguous results. OBJECTIVES: This study tested whether flight simulator performance differs significantly between the menstrual and the luteal phase of the menstrual cycle. METHODS: In a within-subjects design, 24 female pilots were tested twice during their menstrual cycle: once during the menstrual and once during the luteal phase. On both test days they performed a 75-min simulator flight in a Frasca 141, a popular pilot training device. RESULTS: Despite highly significant differences in estradiol (E2) as well as progesterone (P) levels on the 2 test days, and despite excluding subjects with anovulatory cycles from the analyses, there were no significant differences in overall flight performance between the menstrual and luteal phases. We found no significant correlations between E2 or P levels and flight performance. CONCLUSIONS: We found no evidence that the tested menstrual cycle phases and their associated E2 and P levels significantly influence flight simulator performance. We consider these negative findings based on 24 subjects meaningful because previous studies on the influence of menstrual cycle on cognitive performance have not involved complex "real world" tasks such as piloting an aircraft and they obtained inconsistent results.

Adult↗
PubMed2001

Remote memory for public figures in Alzheimer's disease: relationships to regional cortical and limbic brain volumes.

This study examined the relationships between regional cortical and hippocampal brain volumes and components of remote memory (recall, recognition, sequencing, and photo naming of presidential candidates) in 13 individuals with Alzheimer's disease (AD). Recognition and sequencing of remote memory for public figures were associated with regional cortical volumes. Specifically, lower recognition and sequencing scores were associated with smaller parietal-occipital cortical volumes; poorer sequencing was also associated with smaller prefrontal cortical volumes. By contrast, poorer anterograde but not remote memory scores were correlated with smaller hippocampal volumes. Within the constraints of the brain regions measured, these findings highlight the importance of the posterior cortical areas for selective remote memory processes and provide support for the dissociation between cortically mediated remote memory and hippocampally mediated anterograde memory.

Aged↗
PubMed2001

Influence of the menstrual cycle on flight simulator performance after alcohol ingestion.

OBJECTIVE: Previous studies investigating the influence of the menstrual cycle on cognitive functioning of women after alcohol ingestion have obtained inconsistent results. The present study tested the hypothesis that flight simulator performance during acute alcohol intoxication and 8 hours after drinking differs between the menstrual and the luteal phase of the menstrual cycle. METHOD: White female pilots (N = 24) were tested during the menstrual and the luteal phases of their menstrual cycles. On each test day they performed a baseline simulator flight, consumed 0.67 g/kg ethanol, and performed an acute-intoxication and an 8-hour-carryover simulator flight. RESULTS: Subjects reached highly significant increases in estradiol (E2) as well as progesterone (P) levels during the luteal test day. Yet, there were no significant differences in overall flight performance after alcohol ingestion between the menstrual and luteal phases during acute intoxication or at 8-hour carryover. We found no correlations between E, or P levels and overall flight performance. However, there was a statistically significant Phase x Order interaction: Pilots who started the experiment with their menstrual day were less susceptible to the effects of alcohol during the second test day than were pilots who started with their luteal day. CONCLUSIONS: The tested menstrual cycle phases and varying E2 and P levels did not significantly influence postdrink flight performance. Because the present study included a comparatively large sample size and because it involved complex "real world" tasks (piloting an aircraft), we believe that the present findings are important. We hope that our failure to detect menstrual cycle effects will encourage researchers to include women in their investigations of alcohol effects and human performance.

Adult↗
PubMed2001

Context processing in older adults: evidence for a theory relating cognitive control to neurobiology in healthy aging.

A theory of cognitive aging is presented in which healthy older adults are hypothesized to suffer from disturbances in the processing of context that impair cognitive control function across multiple domains, including attention, inhibition, and working memory. These cognitive disturbances are postulated to be directly related to age-related decline in the function of the dopamine (DA) system in the prefrontal cortex (PFC). A connectionist computational model is described that implements specific mechanisms for the role of DA and PFC in context processing. The behavioral predictions of the model were tested in a large sample of older (N = 81) and young (N = 175) adults performing variants of a simple cognitive control task that placed differential demands on context processing. Older adults exhibited both performance decrements and, counterintuitively, performance improvements that are in close agreement with model predictions.

Adult↗
PubMed2000

Combined assessment of tau and neuronal thread protein in Alzheimer's disease CSF.

OBJECTIVE: Comparative study of CSF levels of tau and AD7C-neuronal thread protein (NTP) in patients with AD and control subjects. BACKGROUND: AD is characterized by neurofibrillary tangles composed of the abnormally hyperphosphorylated microtubule-associated protein tau. AD7C-NTP is a proposed AD marker expressed at early stages of neurofibrillary degeneration. METHODS: Enzyme-linked immunosorbent assays specific for tau and AD7C-NTP. CSF samples were obtained from 35 demented patients (25 with antemortem clinical diagnosis of probable AD, 5 with neuropathologic diagnosis of definite AD, 5 with Lewy body pathology), 29 nondemented patients with PD, and 16 elderly healthy control subjects. Receiver operating characteristics (ROC) and multivariate discriminant analysis for AD versus controls. Correlational analysis of CSF tau and AD7C-NTP and of each marker with Mini-Mental State Examination (MMSE) scores was performed. RESULTS: Levels of both tau and AD7C-NTP were significantly elevated in the AD patients compared with control subjects. ROC analysis showed that CSF tau distinguished between patients with AD and nondemented control subjects with 63% sensitivity and 89% specificity, AD7C-NTP with 70% sensitivity and 87% specificity. Combined evaluation of both markers with discriminant analysis raised the specificity to 93% at a 63% sensitivity level. Both markers positively correlated with each other within the AD group, but not among control subjects. CSF levels of AD7C-NTP, but not of tau, showed a small but significant inverse correlation (r = -0.43) with MMSE scores of AD patients. CONCLUSIONS: CSF levels of tau and AD7C-NTP may be useful biomarkers for AD.

Aged↗
PubMed2000

Extent, pattern, and correlates of remote memory impairment in Alzheimer's disease and Parkinson's disease.

Content and contextual memory for remote public figures and events was assessed with a modified version of the Presidents Test in patients with Alzheimer's disease (AD) or Parkinson's disease (PD). Contributions of executive functioning, semantic memory, and explicit anterograde memory to remote memory abilities were also examined. The AD group had temporally extensive deficits in content and contextual remote memory not accountable for by dementia severity. The PD group did not differ from the control group in remote memory, despite anterograde memory impairment. These results support the position that different component processes characterize remote memory, various mnemonic and nonmnemonic cognitive processes contribute to remote memory performance, and anterograde and remote memory processes are dissociable and differentially disrupted by neurodegenerative disease.

Aged↗
PubMed2000

How can we learn about developmental processes from cross-sectional studies, or can we?

OBJECTIVE: Cross-sectional studies are often used in psychiatric research as a basis of longitudinal inferences about developmental or disease processes. While the limitations of such usage are often acknowledged, these are often understated. The authors describe how such inferences are often, and sometimes seriously, misleading. METHOD: Why and how these inferences mislead are here demonstrated on an intuitive level, by using simulated data inspired by real problems in psychiatric research. RESULTS: Four factors with major roles in the relationship between cross-sectional studies and longitudinal inferences are selection of time scale, type of developmental process studied, reliability of measurement, and clarity of terminology. The authors suggest how to recognize inferential errors when they occur, describe how to protect against such errors in future research, and delineate the circumstances in which only longitudinal studies can answer crucial questions. CONCLUSIONS: The simple conclusion is that one must always use the results of cross-sectional studies to draw inferences about longitudinal processes with trepidation.

Aging↗
PubMed2000

An actigraphic comparison of sleep restriction and sleep hygiene treatments for insomnia in older adults.

We compared the efficacy of sleep restriction therapy combined with sleep hygiene, nap modification of sleep restriction therapy combined with sleep hygiene, and sleep hygiene alone as treatments for insomnia in 39 community-dwelling men and women 55 years and older. We used the wrist actigraph as an objective outcome measure for all subjects at baseline, end of treatment, and 3-month follow-up; polysomnography (PSG) was conducted in a subgroup of subjects. Although subjects appeared to follow restriction instructions through follow-up, we found few between-group differences in treatment efficacy. Lack of treatment effect might be explained by the efficacy of HYG as a treatment in itself and the relatively low symptom level in these healthy older poor sleepers. At baseline, actigraphic results were found to correlate more highly than sleep log data with PSG in our sample. Actigraphic total sleep time, in particular, was highly correlated with PSG.

Adult↗
PubMed2000

Structural brain correlates of verbal and nonverbal fluency measures in Alzheimer's disease.

This study examined the relationships between regional brain volumes and semantic, phonological, and nonverbal fluency in 32 participants with Alzheimer's disease (AD). Object but not animal semantic fluency correlated with frontal and temporal gray matter volumes. Phonological fluency was not significantly associated with any brain volume examined. Nonverbal fluency was selectively associated with bilateral frontal gray matter volumes. Hippocampal volumes, although markedly reduced in these patients, were not related to any of the fluency measures. Results lend evidence to the importance of the frontal lobes in the directed generation of nonverbal and verbal exemplars by AD patients. Furthermore, both left- and right-hemisphere regions contribute to the generation of verbal and nonverbal exemplars.

Adult↗
PubMed2000

Relationship of CogScreen-AE to flight simulator performance and pilot age.

OBJECTIVES: We report on the relationship between CogScreen-Aeromedical Edition (AE) factor scores and flight simulator performance in aircraft pilots aged 50-69. METHODS: Some 100 licensed, civilian aviators (average age 58+/-5.3 yr) performed aviation tasks in a Frasca model 141 flight simulator and the CogScreen-AE battery. The aviation performance indices were: a) staying on course; b) dialing in communication frequencies; c) avoiding conflicting traffic; d) monitoring cockpit instruments; e) executing the approach; and f) a summary score, which was the mean of these scores. The CogScreen predictors were based on a factor structure reported by Kay (11), which comprised 28 CogScreen scores. Through principal components analysis of Kay's nine factors, we reduced the number of predictors to five composite CogScreen scores: Speed/Working Memory (WM), Visual Associative Memory, Motor Coordination, Tracking, and Attribute Identification. RESULTS: Speed/WM scores had the highest correlation with the flight summary score, Spearman r(rho) = 0.57. A stepwise-forward multiple regression analysis indicated that four CogScreen variables could explain 45% of the variance in flight summary scores. Significant predictors, in order of entry, were: Speed/WM, Visual Associative Memory, Motor Coordination, and Tracking (p<0.05). Pilot age was found to significantly improve prediction beyond that which could be predicted by the four cognitive variables. In addition, there was some evidence for specific ability relationships between certain flight component scores and CogScreen scores, such as approach performance and tracking errors. CONCLUSIONS: These data support the validity of CogScreen-AE as a cognitive battery that taps skills relevant to piloting.

Aerospace Medicine↗
PubMed2000

A longitudinal study of apolipoprotein-E genotype and depressive symptoms in community-dwelling older adults.

The Apolipoprotein-E (APOE) epsilon 4 allele is a risk factor for Alzheimer's disease (AD) and cognitive decline in older adults. Depression may also be a risk factor for dementia, and depression is important in the differential diagnosis of dementia. The authors performed a 5-year longitudinal study of APOE genotype and change in Geriatric Depression Scale scores in 113 community-dwelling older adults. No association was observed between APOE genotype and change in depressive symptoms. These results do not support the hypothesis that the APOE epsilon 4 allele is associated with depression. Important objections have been raised to APOE genotyping in the diagnosis of AD. However, the specificity of APOE genotyping in AD diagnosis would not appear to be compromised by an association with depression.

Age Factors↗
PubMed2000

A retrospective chart review of gabapentin for the treatment of aggressive and agitated behavior in patients with dementias.

In a 24-patient case series from retrospective chart review, the authors examined the use of gabapentin for the treatment of aggressive and agitated behaviors in nursing home patients with a DSM-IV diagnosis of dementia. On Clinical Global Rating Scale scores, 17 of 22 patients were much or greatly improved; 4 were minimally improved; and only 1 remained unchanged. Two of the 24 patients discontinued use of the medication because of excessive sedation. No other significant side effects were noted in treatment lasting up to 2 years.

Acetates↗
PubMed2000

Ethanol pharmacokinetics in white women: nonlinear model fitting versus zero-order elimination analyses.

BACKGROUND: Studies have shown repeatedly that ethanol pharmacokinetics are not linear, yet most researchers still determine ethanol elimination by linear, zero-order kinetics. The goals of the present work were to: (1) fit four nonlinear pharmacokinetic models to mean breath alcohol concentration (BrAC)-time data of 27 women and determine the best-fit model; (2) fit the determined best-fit model to individual BrAC data and estimate the pharmacokinetic parameters; and (3) compare the method of nonlinear model fitting with the classical zero-order elimination method and determine in which cases the classical approach is justified. METHODS: Twenty-seven healthy white women ingested four drinks (total of 0.67 g x kg(-1)) of ethanol on two test days. Approximately 24 breath ethanol samples (for pharmacokinetic analyses) and one blood sample (for hormonal markers) were taken per day. Pharmacokinetic model evaluation was based on the coefficient of variation, the weighted residual sum of squares, and the sequence of the weighted residuals. Because hormonal changes across the menstrual cycle did not significantly influence ethanol pharmacokinetics, data from the two test days were pooled. RESULTS: The best-fit model was a one-compartment open model with first-order absorption and sequential first-order elimination, followed by Michaelis-Menten elimination kinetics. Fitting this model to the individual BrAC data yielded mean ka = 0.062 hr(-1), Vd = 0.457 L x kg(-1), ke = 0.011 hr(-1), Vmax = 0.136 g x L(-1) x hr(-1), and Km = 0.096 g x L(-1). For the classical analyses, mean time to peak BrAC = 1.83 hr, disappearance rate = 0.179 g x L(-1) x hr(-1), and area under the blood ethanol-time curve (AUC) = 2.884 g x L(-1) x hr. Correlational analyses showed that more frequent drinkers eliminated ethanol significantly faster and reached significantly lower AUC than less frequent drinkers. CONCLUSIONS: After multiple dose ingestion in white women, classical zero-order elimination analyses can be applied only to a limited portion of the descending BrAC-time curve. They seem justified and practical from 0.5 hr after peak BrAC until BrAC reaches 0.2 g x L(-1). To describe ethanol pharmacokinetics across the entire BrAC-time curve, however, sophisticated nonlinear model fitting is required.

Adult↗
PubMed1999

Taking account of between-patient variability when modeling decline in Alzheimer's disease.

The pattern of deterioration in patients with Alzheimer's disease is highly variable within a given population. With recent speculation that the apolipoprotein E allele may influence rate of decline and claims that certain drugs may slow the course of the disease, there is a compelling need for sound statistical methodology to address these questions. Current statistical methods for describing decline do not adequately take into account between-patient variability and possible floor and/or ceiling effects in the scale measuring decline, and they fail to allow for uncertainty in disease onset. In this paper, the authors analyze longitudinal Mini-Mental State Examination scores from two groups of Alzheimer's disease subjects from Palo Alto, California, and Minneapolis, Minnesota, in 1981-1993 and 1986-1988, respectively. A Bayesian hierarchical model is introduced as an elegant means of simultaneously overcoming all of the difficulties referred to above.

Alzheimer Disease↗
PubMed1999

Mnemonic training in older adults: effects of age, length of training, and type of cognitive pretraining.

OBJECTIVES: To improve performance with mnemonic techniques for remembering words and proper names. DESIGN: For word recall, a 2 x 2 factorial in which type of pretraining and length of training were between-subjects manipulations. For proper name recall, a two-group design in which type of pretraining was manipulated between subjects. SETTING: Community. PARTICIPANTS: 268 community-dwelling adults over the age of 55 years who wished to improve their memory. MEASUREMENTS: Recall of words and proper names both before and after training in mnemonics. INTERVENTION: Participants received a 2-week training course on two mnemonic techniques, the method of loci for words and a name association technique for proper names. RESULTS: There was no effect of the pretraining manipulation on proper name recall. For word recall, however, a multiple regression that included age indicated that the older-old participants benefited more from a combination of comprehensive pretraining and extended mnemonic training than did the younger-old. CONCLUSIONS: Increased training time coupled with a comprehensive pretraining regimen can improve the performance of the older-old in using mnemonics; this improved performance cannot be attributed solely to enhanced knowledge of the mnemonic.

Age Factors↗
PubMed1999

Predicting response of older adults to mnemonic training: who will benefit?

OBJECTIVES: To identify profiles of subjects who respond to mnemonic training for serial word and proper name recall. DESIGN: Analysis of J. O. Brooks et al.'s (1999) mnemonic training data using Quality Receiver Operating Characteristic (QROC) and longitudinal regression analyses (LRA). SETTING: Community. PARTICIPANTS: 224 community-dwelling adults 55 years of age and older who wished to improve their memory. MEASUREMENTS: Performance on serial word and proper name tests; performance on cognitive ability tests. RESULTS: Although the QROC and LRA identified several common predictors (baseline performance, mental rotation ability, and paired associate learning), the QROC identified additional predictors and cognitive ability profiles associated with successful response. CONCLUSIONS: Similar degrees of response to mnemonic training are associated with heterogeneous cognitive profiles. This finding highlights the fact that participants rely on a variety of abilities to derive benefit from mnemonic training and thus suggests different avenues from which to approach this training.

Aged↗