PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “cognitive function”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 109 records · Page 6Linked to original sources
PubMed1983

Anticonvulsant drugs, cognitive function, and behavior.

Healthy volunteers as well as patients with epilepsy were studied for 2 weeks in a double-blind crossover design to determine the effect of anticonvulsant drugs on cognitive function and behavior. The healthy volunteers experienced significant deficits in performance with the four drugs examined, phenytoin, carbamazepine, sodium valproate, and clobazam. The most widespread changes were seen with phenytoin; carbamazepine, sodium valproate, and clobazam did not interfere with tests of memory function. The results of the patients' studies showed that (1) when anticonvulsants are reduced, patients receiving polytherapy improve their cognitive function; (2) patients with high serum levels of anticonvulsant drugs demonstrated more cognitive impairment than those with low levels; (3) when carbamazepine is substituted for another anticonvulsant, cognitive function is improved; and (4) in patients receiving monotherapy, high serum levels are linked to greater cognitive impairment than lower levels and the profile of changes differs between the drugs.

Anticonvulsants↗
PubMed1995

The impact of long-term vitamin supplementation on cognitive functioning.

The possibility that the taking of vitamin supplements may influence cognitive functioning was explored. One hundred and twenty-seven young healthy adults took either ten times the recommended daily dose of nine vitamins, or a placebo, under a double-blind procedure, for a year. After 12 months better performance on two measures of attention was found in females who had taken the vitamin supplement, even though the blood status of nine vitamins reached a plateau after 3 months. The use of regression equations demonstrated the association between improved thiamin status and improved performance on a range of measures of cognitive functioning in females rather than males. Although it was not possible to establish the reason for a beneficial response in females rather than males, the evidence that females respond differently to dietary factors was discussed.

Adolescent↗
PubMed1992

The importance of comparative studies and ecological validity for understanding hippocampal structure and cognitive function.

Building from the premise that hippocampal cognitive function has been molded by natural selection under natural environmental conditions, it is argued that traditional laboratory studies likely do not reveal the richness and complexity of hippocampal function. Research on the role of the hippocampal formation in the navigational behavior of homing pigeons is offered as an example to illustrate the advantages of using an ecological approach to understand hippocampal function. It is further proposed that dissimilarities in hippocampal anatomy, physiology, and neurochemistry found between species reflect species differences in the range of functions served by the hippocampal formation, as well as possibly the molecular and cellular mechanisms that support such functions. These differences notwithstanding, it is suggested that, from an evolutionary perspective, the primary function of the hippocampal formation is a role in some aspect of spatial cognition. Dissimilarities in hippocampal structure and function among extant species are viewed as resulting from differences in evolutionary selective pressure and evolutionary history.

Animals↗
PubMed1995

Cognitive functioning and the incidence of limitations in activities of daily living in an elderly community sample.

Although it is well-known that cognitive impairment in the elderly is usually accompanied by limitations in activities of daily living (ADL), it is not known whether cognitive impairment predicts the onset of new ADL limitations. The purpose of this analysis was to determine whether poor scores on a brief measure of cognitive functioning at baseline (1982) would predict the onset of persistent limitations in ADL during the subsequent 3 years, in a probability sample of community-dwelling elderly persons living in New Haven, Connecticut, who were initially free of ADL limitations (n = 1,856). Cognitive functioning was assessed with Pfeiffer's Short Portable Mental Status Questionnaire. Persistent incident ADL limitations were defined as the onset of one or more ADL limitations after 1982, with no subsequent reports of zero ADL limitations. Compared with persons who scored zero to one errors on the Short Portable Mental Status Questionnaire at baseline, persistent, incident ADL limitations occurred more frequently in persons who scored four or more errors (odds ratio for males = 2.72, 95% confidence interval 1.36-5.43; odds ratio for females = 2.60, 95% confidence interval 1.52-4.44) after adjustment for the confounding effects of housing type, age, race, history of chronic health conditions, and incident health conditions. These results suggest that knowledge of scores on brief cognitive function tests can be used to forecast service needs and to develop intervention programs to prepare for the possible onset of ADL limitations.

Activities of Daily Living↗
PubMed1990

[Diffuse bilateral periventricular hyperintensity of unknown origin on MRI spin-echo sequence. Cognitive function and regional cerebral blood flow].

Cognitive function and regional cerebral blood flow (rCBF) were studied in 26 patients (mean age 77.9) who showed bilaterally an ill-defined diffuse periventricular hyperintensity (PVH) on the magnetic resonance imaging (MRI) spin-echo sequence. Diffuse PVH was classified into two groups according to severity, group A (more severe) and group B (less severe); their cognitive impairment was classified into three stages, stage 1 (mildly impaired) through stage 3 (severely impaired). rCBF was assessed by single photon emission computed tomography (SPECT). The result showed that 6 of 7 MRI-group A patients were stage 3, but the stages of 19 group B patients varied. Five of 7 MRI-group A patients showed severe hypoperfusion, but rCBF of group B patients also varied. Nineteen patients had a hypertensive history, but only 10 patients complained of cerebrovascular incidents before admission. All 3 younger patients (one in his fifties and two in their sixties), however, showed hypertension, stepwise neurological deterioration as in Binswanger's disease. These results suggest that there might be various pathogenesis of diffuse bilateral PVH in the elderly and they are different from that of the classical "Binswanger's disease".

Aged↗
PubMed1984

Cognitive function and age at repair of transposition of the great arteries in children.

To assess the effect of the duration of chronic hypoxemia on cognitive function, we studied 38 children with d-transposition of the great arteries and an intact ventricular septum who underwent corrective surgery at six months to six years of age (median, 1.6 years). Tests included the Wechsler Preschool and Primary Scale of Intelligence (WPPSI) in 33 children and the visual-association and auditory-association subtests of the Illinois Test of Psycholinguistic Abilities in 38 and 37 children, respectively. When controlled for social index, age at repair was inversely associated with the WPPSI intelligence-quotient score (P less than 0.01), the visual-association subtest score (P less than 0.01), and the auditory-association subtest score (P less than 0.1). In contrast, age at repair correlated poorly with cognitive function in children with ventricular septal defect, an acyanotic congenital heart defect. These data suggest that postponing repair of a cyanotic congenital heart disease, such as transposition of the great arteries, is associated with progressive impairment of cognitive function.

Age Factors↗
PubMed1992

Cognitive functions, epileptic syndromes and antiepileptic drugs.

Cognitive function of patients on monotherapy specific for their epileptic syndrome has been studied infrequently. We evaluated 7 patients with symptomatic localised epilepsies (SEL) on phenytoin aged 30 +/- 12 (mean +/- standard deviation) years, 8 with idiopathic generalised epilepsies on sodium valproate aged 18 +/- 4 years, 16 with SEL on carbamazepine aged 28 +/- 11 years, and 35 healthy controls aged 27 +/- 11 years. All subjects were of normal intelligence, educated appropriately to age, and led productive lives in the community. Two of the patients on carbamazepine and one on valproate had less than five partial, absence or myoclonic seizures monthly, the remaining were controlled. Carbamazepine serum concentrations were 12 +/- 5 micrograms/ml, phenytoin were 23 +/- 7, and valproate were 62 +/- 23 (mean +/- sd). Tests included immediate recall and recognition for pictures, Stroop test, delayed recall and recognition of pictures. Patients on phenytoin and valproate performed significantly worse than controls on immediate recall, and patients on carbamazepine performed significantly worse than controls in Stroop test (p < 0.01). The results indicate relatively minor effects of the epileptic syndromes and of phenytoin, carbamazepine and valproate on cognition of patients with controlled epilepsy leading productive lives in the community. We conclude that the cognitive deficit found in chronic epileptic patients on poly-therapeutic drug regimen must be multifactorial, and that future studies need to control for all possible variables in order to achieve meaningful results.

Adolescent↗
PubMed1994

Indomethacin and cognitive function in healthy elderly volunteers.

1. Cognitive function was studied after single and multiple doses of indomethacin (I) and matched placebo (P) in 20 healthy elderly volunteers using a double-blind crossover design. 2. Arousal, attention, integration, coordination, memory and mood were investigated using a battery of psychomotor tests and the Hospital Anxiety and Depression Scale. Assessments were performed before and after the first and last doses of a 7 day course of medication. 3. Critical flicker fusion threshold fell by a mean of 1.96% on indomethacin compared with a 1.13% rise on placebo 5 h after the first dose (P = 0.029). A beneficial effect on choice reaction time latency (P = 0.012) was seen both after acute and continuing administration of indomethacin. Performance at the most discriminating level (level 3) of the paired word association test was significantly better following 8 days of treatment with indomethacin in the younger (55-65 year-old) age group (P = 0.001). 4. There was no significant difference in performance on the symbol-digit substitution test and the continuous attention task. No change was seen in hospital anxiety and depression scale scores. 5. These results suggest that performance on tests of sensorimotor coordination and short term memory may improve in healthy volunteers following indomethacin administration, whereas tests of attention and psychomotor speed remain unaffected. However, further controlled studies in rheumatic patients are needed to evaluate fully the psychomotor effects of indomethacin and other NSAIDs in clinical practice.

Aged↗
PubMed1986

Age differences in sensory and cognitive function in elderly Nepalese.

This paper describes age differences in sensory and cognitive function in a cross-sectional sample of 117 Nepalese men aged 50 to 88 years living in a traditional agrarian society. The prevalence of impairment of vision, hearing, vibration sensitivity, and cognitive function is progressively higher in successively older age categories in this society as it is in Western industrial societies. This has practical consequences for everyday life. Men with vision impairment are less likely to retain the esteemed social role of head of an extended household. Men with visual and hearing impairment leave their household compounds less frequently, have less frequent social contacts outside their households, and remain inactive a greater proportion of the time. In this technologically simple society without modern medical remedies, vision and hearing impairments are associated with social roles and daily activity patterns that foster economic and political dependence and social isolation.

Aged↗
PubMed1994

Cognitive functioning and school performance in children with renal failure.

Although previous studies have documented neuropsychological deficits in children with end-stage renal disease, few have evaluated and compared the cognitive functioning and the school performance of children with renal failure. The current study evaluated the influence of chronic renal failure on cognitive functioning and school performance in children and adolescents with end-stage renal disease undergoing dialysis and after renal transplantation. Participants were given standardized IQ and achievement tests to assess cognitive functioning and ability. Academic performance was determined by evaluating grades for the semester in which the testing was performed; a grade point average (GPA) was calculated based on a 4.0-point scale. The 11 dialysis patients and 13 transplant patients were comparable in age, race, sex, and socioeconomic status. Overall IQ and subtest scores demonstrated no differences between the two groups. Performance on the Woodcock-Johnson achievement tests showed that the transplant patients did better on achievement tests of written language (P = 0.04) and in school performance in English compared with dialysis patients (P < 0.05). Furthermore the dialysis patients tended to be below age and grade level in all areas, whereas the transplant patients were achieving at or above these levels. There were significant differences in the age equivalent scores between the dialysis and transplant patients in the areas of mathematics and written language (P < 0.05). However, when grades were evaluated there were no differences in overall GPA or in the mathematics GPA. Days absent were not different between the two groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1982

Air as a vaporizing gas. Cognitive functions in elderly patients undergoing anaesthesia.

The effects of different anaesthetics on cognitive functions in elderly, air-breathing patients undergoing prostatectomy were studied and the results compared with those of patients who received oxygen additional to that in air. The patients received extradural anaesthesia, air and 3-4% ether, air and 0.5% trichloroethylene or nitrous oxide, oxygen and intermittent i.v. morphine or pethidine. The first three groups received no additional oxygen during or after operation; the fourth received oxygen for 12 h after operation. There were 15 patients in each group. The tests used were developed as appropriate for illiterate as well as educated patients. No deterioration of cognitive function was found in any group.

Aged↗
PubMed1992

Epoetin and cognitive function.

The uremia of chronic renal failure (CRF) can alter brain electrophysiology and cognitive function, even in the well-dialyzed patient. The effect of uremia on brain function can be assessed by electrophysiologic techniques such as electroencephalogram (EEG), sensory-evoked potentials (EPs), and cognitive event-related potentials (ERPs), and through a series of neuropsychologic tests. Five tests have been used clinically to measure the speed and efficiency of cognitive functioning and include the following: Number Cancellation, Trailmaking Test, Symbol Digit Modalities Test, Rey Auditory Verbal Learning Test, and Controlled Oral Word Association Test. Test performance by patients with CRF is often below that of healthy controls. Auditory ERPs, a sensitive indicator of subtle changes in central nervous system (CNS) function in uremia, result in the generation of a P300 component wave that varies in amplitude and latency with patient variables such as attention and effort. Although dialysis tends to normalize P300 latencies, the waves remain somewhat prolonged in most patients. The anemia often observed in patients receiving chronic dialysis appears to aggravate uremic encephalopathy. This effect can be reversed when anemia is corrected following administration of recombinant human erythropoietin (epoetin). Improvement in P300 amplitudes, and, in some cases, decreases in P300 latencies correlated well with epoetin-induced increases in hematocrit levels. With the correction of anemia, that component of brain dysfunction not attributable to retention of uremic toxins can largely be reversed.

Anemia↗
PubMed1995

Cognitive function during insulin-induced hypoglycemia in humans: short-term cerebral adaptation does not occur.

It has been suggested that cerebral adaptation may occur in response to short-term hypoglycemia. This was examined in the present study by measuring serial changes in cognitive function and symptoms after 60 min of continuous hypoglycemia. Hypoglycemia was induced with a hyperinsulinemic glucose clamp on two separate occasions in 24 non-diabetic human subjects. Cognitive function was assessed using the following cognitive test battery: Paced Auditory Serial Addition Test (PASAT), Rapid Visual Information Processing (RVIP), Trail-Making B (TMB), Digit Symbol Substitution Test (DSST) and Four Choice Reaction Time (CRT). In condition A the blood glucose was maintained at 4.5 mmol/l throughout. On two separate occasions (condition B and condition C) the blood glucose was stabilised at 4.5 mmol/l for 30 min, lowered to 2.5 mmol/l for 60 min and restored to 4.5 mmol/l for 30 min. In each condition the cognitive test battery was performed immediately after stabilisation of blood glucose at 4.5 mmol/l and the subsequent battery was repeated at different time intervals: condition A--after a further 40 min of euglycemia; condition B--after 5 min of hypoglycemia; condition C--after 40 min of hypoglycemia. Acute hypoglycemia induced a significant deterioration in cognitive function which was manifest in all tests except TMB (P < 0.05), but performance ability did not differ between conditions B and C. Symptom scores, assessed by a scaled questionnaire, increased significantly during hypoglycemia (P < 0.001) but no differences were detected between the scores at 30 min and 60 min.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Toward an understanding of cognitive functioning in geriatric depression.

This paper addresses the questions of whether depression compromises cognition in the elderly and whether discernable patterns of cognitive performances could be differentiated between patients with severe depression and those with organic dementia. Published data on geriatric depression and cognitive functioning are divided in demonstrating a depression effect. Further examination and external validation by new data show that the depression effect on discrete cognitive tasks is (1) small, and (2) sensitive to the confounding of sampling and task variables. Future research must take these factors into account. Patterns of cognitive functioning in depression and dementia are different and can be differentiated using a variety of measures. This review finds the term pseudodementia inappropriate and misleading and recommends that it be abandoned.

Aged↗
PubMedDate not supplied

The effects of mild diastolic hypertension on the results of tests of cognitive function in adults 22 to 59 years of age.

OBJECTIVE: To test the hypothesis that mild diastolic hypertension (90 to 104 mm Hg) may induce asymptomatic impairment of cognitive function. DESIGN: Cross-sectional. SETTING: Community participants recruited to a university-based ambulatory care center. PARTICIPANTS: Three hundred twelve men and women with untreated essential hypertension and 47 normotensive subjects, 22 to 59 years of age. MEASUREMENTS AND MAIN RESULTS: Cognitive function tests measured reaction time to and accuracy in interpreting predetermined visual stimuli, the ability to acquire, reproduce, and change a set of arbitrary stimulus-response associations, and memory and learning of verbal information. These tests were selected to detect subtle differences in performances as opposed to differentiating neurologically normal persons from brain-damaged persons. After controlling for age, gender, and education, results showed that there was no significant difference between the normotensive and hypertensive subjects in two measures of reaction time to and four measures of accuracy in interpreting predetermined visual stimuli, in the measure of arbitrary stimulus-response associations, or in seven memory and learning variables. Although confidence intervals for the differences between means were wide, clinically significant differences were not likely to be present. Younger age was associated with faster reaction times, fewer errors, and better performance on memory and learning tasks, independent of diastolic blood pressure. CONCLUSIONS: The few detectable effects of untreated mild hypertension on cognitive function reported in the literature may be due to chance and are of questionable clinical significance.

Adult↗
PubMed1981

Medical status and cognitive functioning in alcoholic women.

The prevalence of physical health disorders and measures of cognitive functioning were compared for 100 alcoholic and 100 nonalcoholic women matched on age and education. Alcoholic women were less healthy and more impaired on visual-spatial tasks than nonalcoholic women, and there were no relationships between health and cognitive functioning for either group.

Adult↗
PubMed1989

Impact of iron supplementation on cognitive functions in preschool and school-aged children: the Indian experience.

Four studies examined impacts of iron supplementation on school children of various ages and both sexes. The first study investigated impact of iron-folic acid supplements for 60 d on cognition in 94 boys and girls aged 5-8 y. Improvement in total scores of the anemics was significantly higher than the nonanemics in 7-8-y-old children only. The second study assessed impacts of supplementation on cognition in 14 pairs of 5-6-y-old anemic boys, with clear beneficial effects on cognitive function. The third study investigated effects of varying dosages of elemental iron on cognitive function in 48 boys aged 8-15 y, with different levels of improvement. The fourth study investigated impacts of iron supplementation on 163 anemic girls aged 8-15 y with treatment and evaluations at 4 and 8 mo, with significantly improved scores in cognitive function after the eighth month.

Adolescent↗