Biomedical subjects

N Butters

Publications and source records attributed to N Butters.

At least 73 records · Page 4Linked to original sources

PubMed1991

Reduced cerebral grey matter observed in alcoholics using magnetic resonance imaging.

Twenty-eight chronic alcoholics and 36 age- and sex-matched non-alcoholic controls were examined with magnetic resonance imaging and brain morphometric analyses. Results confirmed large increases in subarachnoid cerebrospinal fluid (CSF) volume and mild ventricular enlargement in the alcoholics and revealed associated volume reductions of localized cortical and subcortical cerebral structures. Volume losses in the diencephalon, the caudate nucleus, dorsolateral frontal and parietal cortex, and mesial temporal lobe structures were the most prominent. Significant correlations between increments in cortical and ventricular CSF and decrements in the volume of cortical and subcortical grey matter were noted. Although there was little evidence for relationships between performance on neuropsychological tests and volume of grey matter structures, significant correlations between some cognitive measures and subcortical and cortical fluid volumes were found. The parallels between this pattern of affected structures and recent neuropathological findings are discussed.

Adult↗

PubMed1991

Cognitive performance of alcoholics: a longitudinal evaluation of the role of drinking history, depression, liver function, nutrition, and family history.

To assess the role of drinking history, depression, liver function, nutrition, and family history on cognitive performance, 171 detoxified male alcoholics were administered a brief neuropsychological examination at admission and discharge from an inpatient treatment program and at a 3-month follow-up evaluation. Regression analyses showed that at admission, depression and liver function were significant predictors of neuropsychological performance, whereas at discharge 3 to 4 weeks later only age and an estimate of premorbid intelligence were significant predictors. At the 3-month follow-up, estimates of drinking following discharge and severity of depressive symptoms were major significant predictors of neuropsychological performance. Indices of drinking prior to admission to the treatment program, nutrition, and family history for alcoholism did not predict performance on any of the three test occasions. These findings indicate that in addition to the chronic neurotoxic effect of alcohol a number of different medical and psychiatric factors, as well as the acute effects of alcohol, contribute to the cognitive scores of patients at various points in the clinical course.

Adult↗

PubMed1991

Dementia in institutionalized elderly: relation to sleep apnea.

Sleep apnea is characterized by transient hypoxemias which are thought to affect mental functioning. Accordingly, speculation and research have focussed on relationships between sleep apnea and dementia. We studied 235 nursing home (ie institutionalized) patients (152 women with a median age of 83.5; 83 men with a median age of 79.7) with portable sleep recording equipment. The Mattis Dementia Rating Scale and the Geriatric Depression Scale were given to each. Seventy percent of the patients had five or more respiratory disturbances per hour of sleep and 96 percent showed some dementia. Sleep apnea was significantly correlated with all subscales on the dementia rating scale. There were trivial differences in dementia ratings between those with mild-moderate apnea and those with no apnea. There were significant differences, however, between the latter two groups and those with severe apnea. In particular, items reflecting attention, initiation and perseveration, conceptualization, and memory tasks on the DRS distinguished between those with and without severe sleep apnea. Among those patients with no depression, all patients with severe sleep apnea were also severely demented. Our data suggest that there is a strong relationship between dementia and sleep apnea when the sleep apnea and dementia are severe. Although causality cannot be inferred from associations, our hypothesis for study is that sleep apnea causes deficits in brain function, possibly due to global effects rather than any particular cortical or subcortical structure.

Aged↗

PubMed1991

Magnetic resonance imaging of alcoholic Korsakoff patients.

Eight patients with alcoholic Korsakoff's syndrome were compared to age-matched groups of normal controls and nonamnesic chronic alcoholic patients using magnetic resonance imaging (MRI). Quantitative image-analytic techniques were used to estimate volumes of ventricular and cortical cerebrospinal fluid (CSF), as well as cortical and subcortical grey matter structures. For the nonamnesic alcoholics, these volume analyses revealed large CSF increases with some circumscribed decreases in grey-matter volumes. In contrast, alcoholic Korsakoff patients showed widespread reductions in grey matter volumes in addition to CSF increases, with greatest reductions observed in diencephalic structures. The volume losses that best differentiated the Korsakoff patients from the alcoholic controls included losses in anterior portions of the diencephalon, mesial temporal lobe structures, and the orbitofrontal cortices. These findings suggest that damage to structures other than the mesial thalamic nuclei, such as the hypothalamus and hippocampus, may contribute to the Korsakoff patients' amnesic symptoms.

Aged↗

PubMed1990

Subcortical abnormalities detected in bipolar affective disorder using magnetic resonance imaging. Clinical and neuropsychological significance.

Magnetic resonance imaging was utilized to determine the nature and rate of subcortical abnormalities in bipolar affective disorder. Nine of 19 bipolar patients and no controls demonstrated subcortical signal hyperintensities on blind evaluation of the images. There was no apparent change in the appearance of the hyperintensities in 7 of 7 subjects with abnormal magnetic resonance images who underwent repeated imaging at 1 year. Bipolar patients with abnormalities had a history of more hospitalizations and appeared more impaired on tests of fluency and recall when compared with bipolar patients without abnormalities or with controls. The possible etiology and significance of signal hyperintensities in bipolar affective disorder is discussed.

Adult↗

PubMed1990

Pictorial priming and cued recall in Alzheimer's and Huntington's disease.

A picture fragment test was used to compare the priming and cued recall performances of patients with Huntington's disease (HD), patients with dementia of the Alzheimer type (DAT), and neurologically intact normal control (NC) subjects. On the pictorial priming test, subjects were asked to say "the first thing you think of" when shown incompletely drawn pictures, half of which were previously exposed to the subject during an unrelated naming task. Normal controls and HD patients, but not DAT patients, demonstrated similar increases in their ability to identify fragmented versions of previously seen pictures relative to novel pictures. These results are consistent with the previously observed pattern of preserved and impaired verbal priming ability in HD and DAT patients, respectively. The NC subjects, as expected, also demonstrated better performance on the cued recall than on the priming version of the picture fragment test, whereas the HD patients evidenced the opposite relationship on these two tasks and DAT patients were found to be equally impaired on both tests. This finding provides further support for the notion that HD patients' memory impairment is characterized primarily by an inability to initiate systematic retrieval strategies.

Aged↗

PubMed1990

Normal aging and forgetting rates on the Wechsler Memory Scale-Revised.

The deleterious effects of aging on various cognitive abilities are widely recognized, yet little is known regarding what constitutes "normal" memory test performance in individuals over the age of 74. In this study, forgetting rates for verbal and nonverbal material from the Wechsler Memory Scale-Revised (WMS-R) were examined in groups of older healthy individuals, age 50-70 and 75-95. Despite equivalent scores on measures of global cognitive status and attention/ concentration, the older group demonstrated significantly more rapid forgetting rates on the Visual Reproduction, Verbal Paired Associates, and Visual Paired Associates subtests of the WMS-R. Although patients with Alzheimer's disease also evidence very rapid forgetting on some subtests, the severity and pattern of losses appears useful in differentiating "abnormal" forgetting from that exhibited by normal elderly subjects. Preliminary normative data for normal elderly subjects on the WMS-R are presented, and the need for appropriate norms for elderly individuals is discussed.

Journal Article↗

PubMed1990

Are all subcortical dementias alike? Verbal learning and memory in Parkinson's and Huntington's disease patients.

The utility of the concept of 'subcortical dementia' was investigated by comparing the verbal learning and memory abilities of Parkinson's disease (PD) patients with those of Huntington's disease (HD) patients. Many similarities between the PD and HD groups emerged, including impaired immediate memory spans, inconsistency of recall across learning trials, deficient use of a semantic clustering learning strategy, elevated intrusion rates on delayed recall, impaired recognition memory performance, normal retention of information over delay periods, normal vulnerability to proactive or retroactive interference, and normal types of intrusion errors. The HD subjects, however, displayed inferior free recall, deficient improvement across learning trials, abnormal serial position recall effects, higher perseveration rates, and supranormal improvement on recognition testing compared with free recall. Implications of these results for characterizing memory deficits associated with subcortical system dysfunction are discussed.

Adult↗

PubMed1990

Assessment of AIDS-related cognitive changes: recommendations of the NIMH Workshop on Neuropsychological Assessment Approaches.

This article presents an extended (7-9 hours) and a brief (1-2 hours) battery designed to evaluate early cognitive changes associated with seropositive, asymptomatic persons. The battery was recommended by an NIMH Workgroup which was guided by 10 principles in its development. The domains assessed by the battery are: (1) Indicators of Premorbid Intelligence; (2) Attention; (3) Speed of Processing; (4) Memory; (5) Abstraction; (6) Language; (7) Visuoperception; (8) Constructional Abilities; (9) Motor Abilities; and (10) Psychiatric Assessment. Although the battery assesses a wide range of psychological functioning, specific emphasis has been placed on divided and sustained attention as well as speed of processing and retrieval from working and long-term memory. Descriptions of both the traditional clinical tests and tasks used in cognitive psychology are provided. Although the Workgroup strongly recommends the use of the extended battery in order to ensure the most sensitivity, it recognizes that there may be situations in which this is not possible. In order to increase the likelihood that neuropsychological tests will identify neurologically affected CDC Stage II and III seropositive individuals, the Workshop recommends that each patient's protocol be rated by two trained neuropsychologists using the same clinical criteria. The Workgroup also recommends that a concerted effort be made to incorporate data from the extended and the brief batteries in some central data bank.

AIDS Dementia Complex↗

PubMed1990

Differential impairment of semantic and episodic memory in Alzheimer's and Huntington's diseases: a controlled prospective study.

A controlled prospective study compared the performance of 14 patients with dementia of Alzheimer type (DAT) and 14 patients with Huntington's Disease (HD), who were matched for overall level of dementia, on a battery of semantic and episodic memory tests. The DAT patients were significantly more impaired on measures of delayed verbal and figural episodic memory, and in addition showed a more rapid rate of decline on tests which depend upon the integrity of semantic knowledge (naming, number information, similarities and category fluency). In contrast, the HD patients were significantly worse, and showed a more rapid decline on the letter fluency test, a task especially sensitive to deficiencies in retrieval. The HD patients were also more impaired than DAT patients on a vocabulary test and on copying geometric figures. The observed double dissociations offer compelling evidence that aetiologically distinct forms of dementing illness result in different patterns of cognitive impairment.

Aged↗

PubMed1990

Longitudinal evaluation of dementia of the Alzheimer type: a comparison of 3 standardized mental status examinations.

We administered 3 commonly employed tests of mental status (the Information-Memory-Concentration test [IMC], the Mini-Mental State Examination [MMSE], and the Dementia Rating Scale [DRS]) to 92 patients with probable dementia of the Alzheimer type. The 3 tests were readministered to 55 of the patients (2-year subgroup) approximately 1 year later, and administered a 3rd time to 20 of the patients (3-year subgroup) approximately 2 years after their initial assessment. In all cases, scores on the 3 tests were highly correlated with each other. Examination of the annual rate of change (ARC) in score for the 2-year subgroup revealed an average decline of -3.24 error points on the IMC, 2.81 points on the MMSE, and 11.38 points on the DRS. Of the 3 tests, only the DRS evidenced greater sensitivity to change with increasing dementia severity. In the 3-year subgroup, the ARC between years 1 and 2 was not correlated with ARC between years 2 and 3 for any of the 3 tests. This finding suggests that a patient's rate of progression in 1 year may bear little relationship to future rate of decline.

Aged↗

PubMed1990

Intrusion errors in the figural memory of patients with Alzheimer's and Huntington's disease.

The tendency of patients with dementia of the Alzheimer type (DAT) and Huntington's disease (HD) to produce prior-item intrusion errors on a figural memory task was assessed. Patients' and elderly control subjects' immediate recall of figures from the Visual Reproduction Test (VRT) of the Wechsler Memory Scale (WMS) was scored for the presence of prior-figure intrusion errors (i.e., characteristics unique to one figure included in the reproduction of a subsequent figure). Results indicate that both patient groups produced more prior-figure intrusion errors than did the NC group, and that DAT patients made significantly more intrusion errors in their reproductions than did HD patients matched for overall severity of dementia. These data suggest that prior-item intrusion errors are evident on figural as well as on verbal memory tasks and that DAT patients are more likely to produce such errors than are equally demented patients with a "subcortical" dementia.

Journal Article↗

PubMed1989

Differentiation of Alzheimer's disease and Huntington's disease with the Dementia Rating Scale.

Patients with dementia of the Alzheimer type (DAT) and Huntington's disease (HD) were assessed with the Dementia Rating Scale, a brief mental status examination that provides a global dementia score and subtest scores for attention, initiation, construction, conceptualization, and memory capacities. Although the patients with DAT and the patients with HD were precisely matched in terms of total Dementia Rating Scale score, different subtest score profiles emerged. Patients with DAT were more impaired than patients with HD on the Memory subtest, whereas patients with HD were more impaired than patients with DAT on the initiation subtest. These results are indicative of qualitative differences in the cognitive impairment of the two disorders and demonstrate that such differences can be elucidated with brief mental status examinations.

Aged↗

PubMed1989

A comparison of the category fluency deficits associated with Alzheimer's and Huntington's disease.

The supermarket verbal fluency test of the Dementia Rating Scale (DRS) was administered to 20 patients with mild Alzheimer's disease (Mi-DAT), 20 patients with moderately severe Alzheimer's disease (Mo-DAT), 20 patients with Huntington's disease (HD), and 40 normal control subjects. The findings confirmed previous reports that Mo-DAT patients retrieved fewer words per category of supermarket items sampled and had a greater propensity to generate category labels (superordinates) than did intact controls. Similar disruptions of the structure of semantic knowledge were also noted in the fluency performances of the Mi-DAT and HD patients. The Mi-DAT patients' tendency to generate few exemplars for each category sampled suggested that a significant disruption in the structure of semantic knowledge occurred even in the earliest stages of DAT. When the present fluency findings for the HD patients were considered with previous reports of linguistic changes in this disorder, it appeared that HD patients' deterioration in semantic knowledge involved associative changes rather than the bottom-up breakdown associated with DAT.

Aged↗

PubMed1989

Recognition memory span in mildly and moderately demented patients with Alzheimer's disease.

An abbreviated form of Moss et al.'s (1986) Recognition Span Test (RST) was administered to patients with mild or moderate dementia of the Alzheimer type (DAT) and to intact control (NC) subjects. Memory spans for verbal (i.e., words), spatial and configurational (i.e., faces) information were assessed. Delayed recall (15 s and 2 min) of the words used on the verbal recognition span was also determined. The results showed that both DAT patient groups were impaired on the three recognition tasks and that the spatial and verbal forms differentiated the mildly from the moderately demented patients. The mean overall recognition span scores (spatial + verbal + facial) differentiated between DAT patients and intact controls, with 37 of the 39 patients falling beyond the 95% confidence limits derived from the control subjects' scores. On verbal recall, both the mildly and moderately demented patients were severely impaired and evidenced a very rapid rate of forgetting between the 15-s and 2-min recall attempts. These findings suggest that the RST is not only highly sensitive to memory disorders in the early stages of DAT but also effective in discriminating among various stages of this disorder.

Aged↗

PubMed1989

Graded neuropsychological impairment and elevated gamma-glutamyl transferase in chronic alcoholic men.

This study hypothesizes that distinct biochemical and metabolic disturbances associated with liver injury may be related to specific cognitive changes in alcoholics. In 132 alcoholic men admitted to an alcohol treatment program, increases in gamma-glutamyl transferase (GGT) values were correlated with impairment in several measures of visuoperceptual and visuoconceptual functioning. The association between plasma levels of GGT and neuropsychological performance was independent of the relative contribution of other laboratory measures of liver injury and of alcohol consumption histories. These observations support the hypothesis that elevated levels of GGT are distinctly associated with neuropsychological deficits and suggest that possible mechanisms beyond severe hepatic dysfunction and alcohol consumption underlie cognitive deficits in alcoholics.

Adult↗

PubMed1989

Neuropsychological evidence for multiple implicit memory systems: a comparison of Alzheimer's, Huntington's, and Parkinson's disease patients.

The performances of patients with dementia of the Alzheimer type (DAT), patients with Huntington's disease (HD), and demented and nondemented patients with Parkinson's disease (PD) were compared on 2 tests of implicit memory that do not require the conscious recollection of prior study episodes: (1) a pursuit-rotor motor learning task and (2) a lexical priming test. The HD patients were found to be impaired on the motor learning but not the lexical priming task, whereas the DAT patients evidenced the opposite relationship on these tasks. The demented, but not the nondemented, PD patients were found to be impaired on both tests of implicit memory. For both the HD and PD patients, deficits on the motor learning task correlated significantly with severity of dementia but not with level of primary motor dysfunction. The noted double dissociation between HD and DAT patients indicates that different forms of implicit memory, all of which are intact in amnesia, are dependent upon distinct neuroanatomic systems. Motor skill learning may be mediated by a corticostriatal system, whereas verbal priming may depend upon the integrity of the neocortical association areas involved in the storage of semantic knowledge. The results for the PD patients suggest that the demented PD patients have endured damage to the neurologic systems subserving both motor learning and lexical priming.

Alzheimer Disease↗

PubMed1989

Differentiating Alzheimer's disease from Huntington's disease with the Wechsler Memory Scale-Revised.

The WMS-R represents a significant improvement over the original version of the WMS. Patterns of performance on the five WMS-R indices successfully differentiated patients with a "cortical" (that is, DAT) from patients with a "subcortical" (that is, HD) dementia. The differences between ACI and GMI also indicated that DAT patients' attention and concentration were better preserved than those of equally demented HD patients. Analyses of the differences between GMI and DMI indicated that rapid forgetting was more apparent for DAT than for HD patients in the early stages of these disorders. When savings scores for the Logical Memory and Visual Reproduction tests were used to examine retention over a 30-minute period, both mildly and moderately demented DAT patients demonstrated more rapid forgetting than did HD patients with similar levels of cognitive decline. Discriminant analyses performed with these indices of forgetting showed 95 per cent accurate classification of DAT and elderly controls, and 79 per cent correct classification of DAT and HD patients. Assessment of the patients' tendencies to make prior-item intrusion errors on the Visual Reproduction tests of the WMS and WMS-R yielded significant differences between patient groups and the two versions of the test. Patients with DAT made significantly more prior-figure intrusion errors than did HD patients on both versions of the VRT, but the original WMS form of this figural memory test was more likely to elicit such errors than was the revised version. Despite many improvements in the revised scale, a number of limitations still exist including standardization and a lack of norms for elderly individuals, as well as failures to include tests of verbal recognition and adequate measures of nonverbal memory.

Alzheimer Disease↗