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

Differential effects of lead exposure on components of verbal memory

AIMS

To determine if verbal learning and memory requiring acquisition and retention of information is differentially affected by lead exposure.

METHODS

The Rey Auditory Verbal Learning Test (RAVLT), a test of verbal learning and memory, was administered to 256 English speaking lead smelter workers who had a mean (SD) age of 41 (9.4) years and employment duration of 17 (8.1) years. Lead exposure variables, based on up to 25 years of prior blood lead data, included a mean (SD) current blood lead (PbB) of 28 (8.8) microg/dl, working lifetime time weighted average blood lead (TWA) of 39 (12.3) microg/dl, and working lifetime integrated blood lead index (IBL) of 728 (434.4) microg-y/dl. Associations of these chronic and recent lead exposure variables with measures from the RAVLT were modelled through multiple linear regressions after controlling for age and educational achievement.

RESULTS

PbB was not associated with any of the RAVLT variables. However, TWA and IBL contributed significantly to the explanation of variance of measures of encoding/storage and retrieval but not to immediate memory span, attention, and learning. Grouping study participants by RAVLT performance according to three recognised clinical memory paradigms showed significantly higher TWA and IBL in the group with "generalised memory impairment" after adjusting for age and educational achievement. We examined recall mechanisms in each group by serial position in the word list and found stronger primacy (recall of words from the beginning of the list) in the "no impairment" and "retrieval difficulties" groups while the "generalised memory impairment" group had better performance on recency (recall of words from the end of the list).

CONCLUSIONS

Lead exposure over years and not PbB interfered with the organisation and recall of previously learned verbal material. Chronic lead exposure affects encoding/storage and retrieval of verbal information.

The cognitive effects of opioids

Successful opioid therapy often depends on achieving a balance between analgesic effectiveness and side effects. The risk of opioid-induced cognitive impairment often hinders clinicians and patients from initiating or optimizing opioid therapy. Despite subjective experiences of mental dullness and sedation, objective tests of cognitive functioning do not always demonstrate marked changes following opioid administration. To guide clinical practice, as well as patient and family teaching, pain management nurses should be familiar with literature regarding this topic. The purpose of this article is to review the empiric literature on opioids and cognitive functioning, including the relationships among pain, cognition, delirium, and opioids. In general, research reflects minimal to no significant impairments in cognitive functioning. If impairment does occur, it is most often associated with parenteral opioids administered to opioid-naive individuals. Some evidence suggests that opioids may actually enhance cognitive function and decrease delirium in some patient populations. This article describes this research and explores the clinical implications of the research in this area.

Essentials of the proper diagnoses of mild cognitive impairment, dementia, and major subtypes of dementia

Loss of cognitive function in the elderly population is a common condition encountered in general medical practice. Diagnostic criteria and approaches have become more refined and explicit in the past several years. Precise diagnosis is feasible clinically. In this article, the precursor state and major subtypes of dementia are considered. Mild cognitive impairment is the term given to patients with cognitive impairment that is detectable by clinical criteria but does not produce impairment in daily functioning. When daily functioning is impaired as a result of cognitive decline, dementia is the appropriate syndromic label. Specific causes of dementia tend to have distinctive clinical presentations: the anterograde amnesic syndrome of Alzheimer disease; the syndrome of dementia with cerebrovascular disease; the syndrome of Lewy body dementia with its distinctive constellation of extrapyramidal features, disordered arousal, and dementia; the behavioral-cognitive syndrome of frontotemporal dementia; the primary progressive aphasias; and the rapidly progressive dementias. Because dementia syndromes have distinctive natural histories, precise diagnosis leads to a better understanding of prognosis. As new treatments become available for Alzheimer disease, the most common of the dementias, accurate diagnosis allows the appropriate patients to receive treatment.

Distinct serial position profiles and neuropsychological measures differentiate late life depression from normal aging and Alzheimer's disease

Geriatric depression is associated with cognitive deficits that share similar features with Alzheimer's disease (AD) and normal aging. This study examined cognitive profiles and serial position effects in patients with geriatric depression (N=20) or AD (N=32) and in elderly controls (N=18). Groups were compared on two measures of serial position of the California Verbal Learning Test (CVLT), scaled scores and regional scores. Newly devised regional scores measure the percentage of items recalled as a function of the possible number of items presented from three regions of the list. Regional scores significantly differentiated depressed from control groups, with reduction of recalled items from the middle region. Scaled scores distinguished the depression from the AD groups on primacy and recency regions, with the characteristic recency effect seen in the AD group. Deficits in regional scores of the middle region are discussed in the context of lower resources in depression.

Neuropsychological assessment for management of patients with deep brain stimulation

The inclusion of cognitive and behavioural criteria has been recommended for the management of patients with deep brain stimulation. A neuropsychological assessment may contribute to different issues: (1) selection of the best candidates for surgery, (2) evaluation of the consequences of surgery, (3) research of the best electrode implantation. Recent neuropsychological studies indicate that (1) with appropriate inclusion criteria, the effects of surgery on cognitive functions are limited; (2) an aggravation of behavioural disorders might be related to subthalamic nucleus (STN) stimulation and depend on electrode location; (3) subthalamic nucleus stimulation, but not the internal globus pallidus stimulation, improves psychomotor efficiency and working memory. These results would suggest that the implanted electrodes are not solely targeting the motor circuit and that the cognitive and motor circuits are not completely segregated.

Core assessment program for surgical interventional therapies in Parkinson's disease (CAPSIT-PD)

In 1992 the Core Assessment Program for Intracerebral Transplantations (CAPIT) was published providing the minimal requirements for a common patient evaluation protocol. Despite the intent, the program was thought to be too laborious to carry out in large scale trials, and it also lacked evaluations of cognitive functions and quality of life. Moreover, the CAPIT was designed for neural transplantation only and has not been revised since. Since then, pallidotomy and deep brain stimulation have emerged as additional treatment modalities but there exists no common tool for evaluation of, and between, the techniques. In 1996, within the framework of NECTAR (Network for European CNS Transplantation and Restoration), a dedicated program entitled "Neurosurgical Interventions in Parkinson's Disease" (NIPD) was funded by the European Union Biomed 2 program to develop a new Core Assessment Program for Surgical Interventional Therapies in PD (CAPSIT-PD) and to establish an European registry for patients with PD subjected to functional neurosurgery. This article presents the recommendations of this new program.

The Mattis Dementia Rating Scale in nursing home octogenarians and nonagenarians: effects of age and education

Despite their increasing representation in the population, little is known about the neuropsychological test performance of the oldest old, particularly those who live in residential settings. Limited published data and clinical experience suggest that this group is more likely to perform in the impaired range on standardized tests when cut-offs developed with younger groups are used. We examined the Dementia Rating Scale (DRS) performance of 82 nondemented nursing home residents, aged 80 to 99, with a mean education level of 11 years. Using published norms and cutoffs, a large percentage of this sample performed in the impaired range, particularly on the initiation and conceptualization subtests and on the total score. Education, but not age, was significantly related to performance in this sample. Percentages of patients misclassified were substantial in all groups, but were higher in those with less than 13 years of education. Using a lower total-score cutoff of 110 reduced the percentage of misclassifications markedly. We recommend the development and use of revised cutoff scores for the evaluation of very elderly nursing home residents.

Word-list forgetting in young and elderly subjects: evidence for age-related decline in transferring information from transitory to permanent memory condition

This study aimed at investigating different memory components involved in word list forgetting by young and elderly healthy individuals. For this purpose, we analyzed in 55 young (age range 20-35) and 50 aged (age range 60-80) healthy subjects the memory decay passing from the fifth immediate to the delayed recall trial of the Rey's Auditory Learning task as a function of the position of the words in the list. Young and elderly groups displayed the same forgetting rate for words recalled from the primacy and mid-list tracts of the serial position curve. However, memory loss for the recency positions was disproportionately larger in the elderly than in the young group. These data demonstrate that aged subjects rely on short-lived memory processes in immediate recall of terminal list items more extensively than young subjects and, as a consequence, a larger proportion of words become inaccessible to them following a delay.

The differential pattern of memory deficit in normal aging and dementias of different etiology

The study explored encoding, storage, and retrieval components of memory functioning in four groups of subjects: (1) normal elderly; (2) elderly subjects in the early prestages of DAT; (3) elderly subjects with a more advanced DAT; (4) younger subjects in the early prestages of AIDS dementia. Each group consisted of 26 subjects, who were administered the Rey Auditory-Verbal Learning Test. The results suggest impaired encoding and retrieval in the DAT groups. The AIDS group demonstrated deficient storage and retrieval. Their pattern of memory deficits was similar to that seen in normal aging. The results speak in favor of the hypothesis of subcortical nature of neurological changes in normal aging.

Rey Auditory-Verbal Learning Test: structure analysis

One of the major advantages of the Rey Auditory-Verbal Learning Test (AVLT) is its multiple measures of learning and memory. This study evaluated empirically whether the different scores are, in fact, not merely different expressions of a single factor, but, rather, measures of different memory domains. The Rey AVLT was administered to 146 normal subjects. Factor analyses produced one, two, or three factors depending on the combination of scores included in the analysis and on the criteria used to determine the number of factors. The basic factors identified were acquisition and retention. The latter can be subdivided further into storage and retrieval, thus yielding a total of three factors.

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.

Rey Auditory Verbal Learning Test performance of a Federal corrections sample with acquired immunodeficiency syndrome

The Rey Auditory-Verbal Learning Test (AVLT) was administered to 30 inmates from three United States Federal corrections facilities. Fifteen were HIV seropositive and carried a diagnosis of AIDS; 15 were seronegative controls. The groups were comparable in age, education, sex, estimated premorbid IQ, and ethnic make-up. Both groups learned across trials, and produced similar acquisition curves. They also showed equivalent registration, but controls performed significantly better than subjects with AIDS on AVLT Trials II, IV, V, Recognition, and sum of I through V. AIDS subjects made significantly more intrusion errors than controls, suggesting that seropositive inmates performed more poorly, at least in part, because they experienced difficulty discriminating relevant from irrelevant responses during recall. Evaluation of serial position effects suggested that AIDS subjects experienced recall problems only with the middle segment of the word list. This finding may be unique to persons with AIDS and is consistent with the view that distinct clinical groups produce different recall patterns.