Biomedical subjects

J Jolles

Publications and source records attributed to J Jolles.

At least 73 records · Page 4Linked to original sources

PubMed2000

Cerebral white matter lesions and cognitive function: the Rotterdam Scan Study.

Cerebral white matter lesions (WMLs) have been associated with cognitive dysfunction. Whether periventricular or subcortical WMLs relate differently to cognitive function is still uncertain. In addition, it is unclear whether WMLs are related to specific cognitive domains such as memory or psychomotor speed. We examined the relationship between periventricular and subcortical WMLs and cognitive functioning in 1,077 elderly subjects randomly sampled from the general population. Quantification of WMLs was assessed by means of an extensive rating scale on 1.5-T magnetic resonance imaging scans. Cognitive function was assessed by using multiple neuropsychological tests from which we constructed compound scores for psychomotor speed, memory performance, and global cognitive function. When analyzed separately, both periventricular and subcortical WMLs were related to all neuropsychological measures. When periventricular WMLs were analyzed conditional on subcortical WMLs and vice versa, the relationship between periventricular WMLs and global cognitive function remained unaltered whereas the relationship with subcortical WMLs disappeared. Subjects with most severe periventricular WMLs performed nearly 1 SD below average on tasks involving psychomotor speed, and more than 0.5 SD below average for global cognitive function. Tasks that involve speed of cognitive processes appear to be more affected by WMLs than memory tasks.

Aged↗

PubMed2000

Habitual caffeine consumption and its relation to memory, attention, planning capacity and psychomotor performance across multiple age groups.

The present study evaluated the association between habitual caffeine intake via coffee and tea and cognitive performance. This was done as part of a larger research programme into the determinants of cognitive ageing (the Maastricht Aging Study: MAAS). Possible withdrawal effects that may have explained in part the positive association between performance and intake in an earlier study were controlled for. In addition, all cognitive tests in this study were administered under strict laboratory conditions. A group of 1875 healthy adults, stratified for age (range 24 - 81 years), sex, and general ability, were screened for habitual intake of coffee and tea and took part in extensive cognitive testing. Multiple regression analysis with control for age, sex, socio-demographic variables, and substance use showed that habitual caffeine consumption was significantly related to better long-term memory performance and faster locomotor speed. No relationships were found between habitual caffeine consumption and short-term memory, information processing, planning, and attention as measured with the Stroop Test. Moreover, no difference in sensitivity to caffeine intake between different age groups was found, suggesting that caffeine intake did not counteract age-related cognitive decline. Several recommendations are made to improve the design of future studies in this field. Copyright 2000 John Wiley & Sons, Ltd.

Journal Article↗

PubMed2000

Neuropsychology of infarctions in the thalamus: a review.

From a review of the literature on the consequences of thalamic infarctions, it may be concluded that memory problems taking the form of an amnesic syndrome are dependent upon the integrity of the mammillo-thalamic tract (MTT). Memory problems incompatible with an amnesic syndrome however, appear to result from thalamic infarctions involving other areas of the thalamus but which leave MTT intact. In contrast, executive dysfunctions could not be shown so readily to depend upon a single structure of the thalamus. The results indicate that damage to the mediodorsal nucleus of the thalamus, the midline nuclei or the intralaminar nuclei, or a combined lesion of these structures may be responsible for deficits of executive functioning.

Cerebral Infarction↗

PubMed2000

The nature of the effect of female gonadal hormone replacement therapy on cognitive function in post-menopausal women: a meta-analysis.

We reviewed epidemiological and experimental studies of female gonadal hormone replacement therapy (HRT) on cognitive function in post-menopausal women and carried out meta-analyses. In healthy ageing women, HRT has small and inconsistent effects that include enhancement of verbal memory, abstract reasoning and information processing. Epidemiological studies show larger effects than experimental studies, which is not related to sample size. Important confounds may be that women who start using HRT are healthier than women who do not. Also, controlling for socio-economic status diminishes the effect of HRT. The effects of HRT may depend on the age and type of menopause and the therapeutic intervention used, with the most widely used drug, Premarin, having least effect. However, the effects are independent of mood and climacteric symptom alleviation. There is a paucity of experimental studies that include healthy elderly women. The evidence for an estrogen deficiency in women with dementia and cognitive dysfunction is inconsistent. Nevertheless, epidemiological studies suggest that HRT protects against the development of clinically diagnosed Alzheimer's disease. However, poor recall of HRT use by patients and altered physician behaviour may have confounded the effects. Surprisingly, both healthy and demented women with low education seem to benefit most from HRT. Three recent controlled experimental studies using Premarin showed no effects of HRT in preventing further cognitive decline in women who already have Alzheimer's disease. Duration of treatment seems to play an important role, with beneficial effects declining-and even reversing-with longer treatment in women with Alzheimer's disease.Future research should further investigate the cognitive effect of different HRT preparations, serum estrogen levels, and the interactions of HRT with age, menopausal status and existing protective (e.g. education) and risk factors (e.g. smoking and apolipoprotein E genotype) for cognitive decline and Alzheimer's disease.

Age Factors↗

PubMed2000

Does migraine headache affect cognitive function in the elderly? Report from the Maastricht Aging Study (MAAS).

The aim of this study was to examine two aspects of cognitive functioning-information processing speed and memory-in both young/middle-aged and older subjects with and without migraine, using data from a large population-based sample. We found that, although age had a large effect on processing speed and memory, migraine did not influence cognitive performance. In addition, there was no significant interaction between age and migraine on processing speed and memory. Our results suggest that, in the general population, migraine does not seriously affect cognitive functioning in young/middle-aged or older adults.

Adult↗

PubMed2000

Mild hearing impairment can reduce verbal memory performance in a healthy adult population.

We studied to what extent immediate and delayed recall in an auditory verbal learning paradigm was affected by basic information processing speed (digit copying) and hearing acuity (average hearing acuity at 1, 2 and 4 KHz at the better ear). A group of 453 individuals in the age between 23 and 82 years with no overt hearing pathology was recruited from a larger study of cognitive aging (Maastricht Aging Study, MAAS). After controlling for age, sex, educational level, and processing speed it was found that a mild to moderate hearing loss predicted lower verbal memory performance. Auditory administered verbal memory tests can underestimate true memory performance, particularly in older individuals with unknown hearing status.

Adult↗

PubMed2000

Distinction between preclinical Alzheimer's disease and depression.

OBJECTIVE: To assess the prevalence of depression in subjects with preclinical Alzheimer's disease (AD) and to investigate the possibility of differentiating subjects with preclinical AD and depression from subjects with depression-related cognitive impairment. DESIGN: A prospective, observational cohort study. SETTING: An outpatient memory clinic of a university-affiliated hospital. PARTICIPANTS: Nondemented subjects with cognitive impairment older than 55 years (n = 111) without neurological or somatic causes for the cognitive impairment. MEASUREMENTS: At baseline, data were collected on patient characteristics, the severity of depression, and cognitive functioning. The course of the cognitive impairment and the presence of dementia were assessed after 2 and 5 years. RESULTS: Twenty-five subjects had preclinical dementia with Alzheimer's type dementia at follow-up. Sixty percent of these subjects (n = 15) were depressed at baseline. Subjects with depression and preclinical AD had at baseline a poorer performance on the cognitive tasks and were older than the subjects with depression-related cognitive impairment. Logistic regression with backward step selection selected age and memory performance as the best predictors for Alzheimer's type dementia in the depressed subjects. The specificity of these predictors for the diagnosis of future Alzheimer's type dementia in depressed subjects was 94%, sensitivity was 90%, positive predictive value was 90%, and negative predictive value was 94%. CONCLUSIONS: Depression is common in preclinical AD. Depressed subjects with preclinical AD can be accurately differentiated from subjects with depression-related cognitive impairment by age and the severity of the memory impairment. Research that aims to investigate preclinical AD should not exclude a priori subjects with depression inasmuch as preclinical AD is often accompanied by depression.

Aged↗

PubMed2000

Normal cognitive performance in patients with chronic alcoholism in contrast to patients with Korsakoff's syndrome.

This study investigated which cognitive deficits are associated with chronic alcoholism. Neuropsychological profiles and MRI brain structure volumes of 14 patients with Korsakoff's syndrome, 15 patients with chronic alcoholism, and 16 healthy control subjects were compared. The patients with alcoholism had a normal cognitive performance and normal brain structure volumes. The patients with Korsakoff's syndrome had performance deficits on tests of memory, visuoperceptual, and executive functions, as well as reduced brain structure volumes. The results suggest that the cognitive deficits cannot be ascribed to mere chronic consumption of alcohol. If cognitive deficits are present in patients with chronic alcoholism, this may point to an underlying brain disorder.

Adult↗

PubMed2000

Cognitive performance in relation to MRI temporal lobe volume in schizophrenic patients and healthy control subjects.

The aim of this study was to identify whether specific deficits in cognitive processing are present in schizophrenia and whether these are related to the volume of temporal and limbic structures. Twenty-seven schizophrenic outpatients were compared with 19 matched control subjects. Compared with control subjects, patients performed complex tasks disproportionately worse than they performed simple tasks. No group differences were found with regard to temporal and limbic volume. Volume of the parahippocampal gyrus was correlated with cognitive performance. The findings are interpreted as evidence for a dysfunction in the maintenance of task-relevant information and the inhibition of irrelevant information.

Adult↗

PubMed2000

Cognitive dysfunctions and white matter lesions in patients with bipolar disorder in remission.

OBJECTIVE: To compare cognitive functioning in relation to white matter lesions in bipolar disorder in remission and schizophrenia. METHOD: Cognitive performance and the occurrence of white matter lesions on MRI images of the brain were assessed in 22 patients with bipolar disorder in remission, 22 patients with schizophrenia and 22 healthy volunteers. RESULTS: Performance of tests of memory, speed and cognitive flexibility was significantly impaired in both patient groups. The frequency of white matter lesions did not differ significantly between the three groups. No differences in cognitive performance were found between patients with white matter lesions and patients without such lesions. CONCLUSION: White matter lesions apparently do not underlie cognitive deficits that are found in patients with bipolar disorder in remission and in patients with schizophrenia.

Bipolar Disorder↗

PubMed1999

A controlled study of temporal lobe structure volumes and P300 responses in schizophrenic patients with persistent auditory hallucinations.

Recent studies of cerebral pathology in patients with schizophrenia have focused on symptomatological and electrophysiological correlates of reduced temporal lobe structure volumes. Volume deficits of the left superior temporal gyrus have been correlated with auditory hallucinations as well as to left-sided P300 amplitude reduction. However, caution is needed to interpret correlational data as evidence of a specific relationship. Therefore, a controlled study was undertaken on schizophrenic patients with and without auditory hallucinations. MRI-defined volumes of the left superior temporal gyrus and other temporal lobe structures were quantified from 3-mm coronal slices in 15 schizophrenic patients with chronic auditory hallucinations (hallucinators), 15 schizophrenic patients without auditory hallucinations (nonhallucinators) and 17 healthy controls. In all subjects a simple oddball paradigm was used to elicit P300 responses at temporal and centro-parietal electrode sites. No evidence was found for volume reductions of temporal lobe structures in the combined patient group compared with controls, or in the hallucinators compared with the nonhallucinators. The patients did show left P300 amplitude reduction compared with controls, particularly in the hallucinator group. Correlations between volumes of left temporal lobe structures and left P300 amplitudes were low and not significant. The results of the present study do not indicate that auditory hallucinations and associated abnormal electrophysiological activity are the consequence of atrophy of localized temporal lobe structures. However, replication in a larger sample of subjects is needed before firm conclusions can be drawn.

Adult↗

PubMed1999

Quantitative analysis of magnetization transfer images of the brain: effect of closed head injury, age and sex on white matter.

Magnetization transfer (MT) imaging has an application in quantitative assessment of cerebral white matter. Previously published postprocessing methods have inherent problems, and therefore a new analysis technique is presented. This technique was found to be more sensitive for white matter changes in patients with a postconcussional syndrome, compared to other methods previously described. Because of the potential application of this technique in longitudinal and group studies, age and sex dependence of the MT ratio (MTR) of white matter were studied. In a group of 51 healthy subjects, a decrease in the mean MTR as well as an increasing distribution width of the MTR was found with increasing age. The mean MTR in males was higher than in females. These results stress the need to take age and sex into account when interpreting MTR data. Magn Reson Med 42:803-806, 1999.

Adult↗

PubMed1999

Medial temporal lobe atrophy and memory dysfunction as predictors for dementia in subjects with mild cognitive impairment.

To determine whether the medial temporal lobe is atrophic in subjects with mild cognitive impairment, and whether atrophy of this structure is a better predictor of dementia than memory dysfunction. Forty-five noninstitutionalized subjects aged 65-85 years were randomly selected from a population based study to obtain a sample with Alzheimer's disease (AD; n = 7), and a clinically nondemented sample (n = 38). Twenty of the latter subjects displayed some cognitive impairment and fulfilled CAMDEX criteria for "minimal dementia." Coronal T1-weighted magnetic resonance imaging was used to visualize the medial temporal lobe. The volume of the parahippocampal gyrus and hippocampus was measured, and medial temporal lobe atrophy was assessed qualitatively. The memory subscore from the CAMCOG was used as a measure of memory functioning. The follow-up period was 3 years. Nine subjects who were diagnosed as being minimally demented at baseline met the criteria for AD during follow-up. At baseline the volume of the parahippocampal gyrus of these subjects was smaller than that of the other subjects with minimal dementia. The memory score was the best predictor of clinical outcome. All medial temporal lobe measures increased the accuracy of prediction compared with only the memory score, by reducing the number of false-negative classifications of dementia. Severe medial temporal lobe atrophy is present even in some subjects with mild cognitive impairment and is an indicator of subsequent AD. The absence of medial temporal lobe atrophy, however, does not exclude the development of dementia. In the majority of subjects memory impairment was a better predictor of dementia than atrophy of the medial temporal lobe. The combination of the two increased predictive accuracy. Nondemented subjects with severe atrophy of the medial temporal lobe could be enrolled in drug trials aimed at slowing the progression of AD.

Aged↗

PubMed1999

1998 Curt P. Richter Award. The effect of hormone replacement therapy on cognitive function in elderly women.

Although evidence seems to indicate favorable effects of hormone replacement therapy (HRT) on cognitive functions and mood in elderly healthy and demented women, some questions remain. For instance, the nature of the long term effect of HRT, e.g. in preventing cognitive decline is still unclear. In this respect, the addition of progestagens in combined HRT has been mentioned to oppose some of the beneficial effects of estrogens. The present paper aims to illuminate these questions and presents two studies. In the first study, the long term effects of combined HRT in healthy postmenopausal women was investigated using a parallel groups (HRT-users vs. controls) design. HRT subjects were always tested during the estrogen-progestagen phase. Results indicated that after 6 and 12 months, women in the HRT-treatment group had higher scores on several indicators of the subjective feeling of well being (sleep, physical and psychological complaints) than matched controls, although at baseline both groups were not severely impaired. Effects of HRT on memory functions were seen when HRT treated subjects were compared with their own baseline functioning, but not when compared with controls. Hence, the addition of progestagen did not oppose the effects of estrogens on subjective feelings of well being or on memory. Our second (case-control) study involved women of middle-age who were unaware of the purpose of the experiment. No positive effects of HRT use on subjective scales of well being or on memory were found. However, women with HRT were faster on basic sensorimotor speed tasks as compared with controls. It should be kept in mind that double blind testing in an experimental study is difficult due to withdrawal bleeding and the reduction of flushes. Expectancy effects may have confounded the results of the first study. However, our findings indicate that the use of a particular design and type of memory test can explain the controversial results of studies into the effect of HRT on cognitive function. Furthermore, it was concluded that HRT has a global activating, instead of specific direct effect on cognitive functions.

Affect↗

PubMed1999

Cognition-enhancing properties of subchronic phosphatidylserine (PS) treatment in middle-aged rats: comparison of bovine cortex PS with egg PS and soybean PS.

There are various clinical and non-clinical studies that have indicated that phosphatidylserine (PS) treatment can improve cognitive functions in humans and other animals. However, treatment with PS derived from bovine cortex is not desirable because of possible transfer of infectious diseases. The present study investigated the cognition-enhancing properties of different types of PS in rats. Seventeen-month-old male Fischer 344 rats were treated daily with a dose of 15 mg/kg of PS derived from bovine cortex (BC-PS), soybean (S-PS), egg (E-PS), or vehicle (n = 9 for each group). The effects of treatment were evaluated in three different behavioral tests. An open field test was conducted to examine the effects of treatment on psychomotor behavior. Two other tests (Morris water escape task and two-way active avoidance) assessed treatment effects on the cognitive performance of rats. Treatment with the different forms of PS did not affect the psychomotor or spatial discrimination performance of the rats. In accordance with previous studies, the cognition-enhancing effects of BC-PS were observed in the two-way active avoidance task. It appeared that the cognition-enhancing effects of S-PS were not different from those of BC-PS. The performance of rats treated with E-PS did not deviate from that of vehicle-treated rats. On the basis of the present study, it was concluded that S-PS, but not E-PS, may have comparable effects on cognition when compared with BC-PS.

Animals↗

PubMed1999

Caffeine improves cognitive performance after strenuous physical exercise.

The effects of three carbohydrate electrolyte solutions (CES) containing different amounts of caffeine on cognitive function and the combined effects of these drinks and exercise on cognitive functions were investigated in a double-blind, cross-over study. On five separate occasions, fifteen endurance trained male athletes (23.3 years) received water placebo, CES placebo (68.8 g/l), and three CES drinks containing low, medium and high dosages of caffeine (150, 225 and 320 mg/l). Each occasion, 8 ml/kg of the drink was consumed before -- and 6 ml/kg of the drink was consumed during an all-out 1 hour time trial on a bicycle ergometer. Cognitive (attentional, psychomotor, and memory) tests were carried out immediately before and immediately after exercise. Before exercise, long term memory was improved by CES plus low dose caffeine compared to both placebos. Immediately after exercise, all cognitive functions were improved by CES plus low- and medium-dose caffeine compared to placebo. These results comprise the first practical demonstration of the cognition improving effects of low amounts of caffeine in CES after strenuous physical exercise.

Adult↗

PubMed1999

The behavioural assessment of the dysexecutive syndrome as a tool to assess executive functions in schizophrenia.

Recent research into the cognitive dysfunctions in schizophrenia has focused on executive deficits. This study investigates performance of patients with schizophrenia on the recently developed Behavourial Assessment of the Dysexecutive Syndrome (BADS). Matched groups of 24 patients with schizophrenia and 17 healthy volunteers were administered the BADS, the Modified Card Sorting Test (MCST), the Tower of London (TOL), a test of general intelligence, and measures of daily functioning. Performance of the schizophrenic group was significantly below that of the control group on the BADS and the MCST, but not on the TOL. The BADS correlated weakly with the MCST. Both tests showed a modest correlation with daily functioning. The BADS appears to offer a useful contribution to the assessment of executive deficits in schizophrenia.

Adult↗

PubMed1999

How ageing and social factors affect memory.

OBJECTIVES: To explore the relationships between lifestyle and memory, and determine whether social factors influence memory. METHODS: the relationship between memory and lifestyle was examined in 497 adults aged 25-80 years, using the Mectamemory in Adulthood questionnaire. We asked about sports activity and perceived activity, participation in voluntary organizations and social contacts. RESULTS: Activity and frequent contact with friends and family were related to higher memory capacity scores. Those with higher capacity scores were also younger, had better health and a stronger internal locus of control. In contrast, people with higher anxiety scores had more symptoms and less education, and were more externally oriented. CONCLUSIONS: people who consider themselves socially and physically active also consider their memory capacity to be good and are less anxious about their memory than less socially and physically active people. Perceived memory change appears to be predominantly influenced by ageing, whereas memory capacity and memory anxiety are more influenced by social factors.

Adult↗