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At least 1,099 records · Page 61Linked to original sources
PubMed2000

Low dose anandamide affects food intake, cognitive function, neurotransmitter and corticosterone levels in diet-restricted mice.

This investigation reports the possible role of the endocannabinoid anandamide on modulating the behavioral and neurochemical consequences of semi-starvation. We studied the effect of very low dose anandamide (0.001 mg/kg) administration on food intake, cognitive function and catecholaminergic and serotonergic pathways in two murine brain areas concerned with appetite (hypothalamus) and learning (hippocampus), and the peripheral corticosterone response to the stress of 40% diet restriction. Anandamide-treated mice consumed 44% more food (P<0.05) during 1 week of 2.5-h feeding each day. In the hypothalamus, there were significantly increased concentrations of norepinephrine (P<0.01), dopamine (P<0.05) and 5-hydroxytryptamine (5-HT) (P<0.001). In the hippocampus, anandamide increased significantly norepinephrine and dopamine, but decreased 5-HT (all at P<0.001). Diet restriction was accompanied in both areas by a significant decrease in all neurotransmitter concentrations that were partially restored by anandamide for dopamine and 5-HT, but not for norepinephrine. In animals on diet restriction, anandamide significantly improved impaired maze performance. Norepinephrine turnover and plasma corticosterone levels were also raised significantly by anandamide. The fact that low dose anandamide improved food intake, cognitive function and reversed some of the neurotransmitter changes caused by diet restriction, might have implications for the treatment of cachexia associated with acquired immunodeficiency syndrome (AIDS) and cancer, for mood changes sometimes associated with dieting, and in the extreme case, of patients with anorexia.

Animals↗
PubMed2000

Quality of life and cognitive function of liver transplant patients: a prospective study.

The presence of cognitive impairment in end-stage liver disease is well recognized, as are patient reports of an impoverished quality of life. The aim of this study is to systematically evaluate the effect of orthotopic liver transplantation (OLT) on these factors. Thirty-two adult patients activated for OLT participated in the study. Assessments were made on activation and at 1, 3, and 9 months post-OLT, with 24 transplant recipients available for reassessment at 9 months. Two control groups (10 patients with nonalcoholic cirrhosis and 10 healthy volunteers) also completed the test protocol at four 2-month intervals. The test battery included the Austin Quality-of-Life Scale, Weschler Adult Intelligence Scale-Revised, Benton's Controlled Oral Word Test, and the Complex Figure of Rey. The OLT group showed significant improvement in cognitive performance and their reported quality of life. These changes were evident by 3 month post-OLT and remained stable at subsequent testing. The control groups typically remained stable over test occasions. Clearly, OLT extends life and, most importantly, improves patients' quality of life and their cognitive functioning.

Adult↗
PubMed1992

Mechanisms of interhemispheric transfer and patterns of cognitive function in acallosal patients of normal intelligence.

We investigated interhemispheric transfer and cognitive function in two boys with normal intelligence in whom agenesis of the corpus callosum was identified following minor head trauma. In patient 1, magnetic resonance imaging scan showed agenesis of the corpus callosum and absent anterior commissure. Results of visual interhemispheric transfer tasks suggested degradation in transfer of information to the left hemisphere. Results of a tactile interhemispheric transfer task suggested degradation of access to the right hemisphere. In patient 2, magnetic resonance imaging scan showed agenesis of the corpus callosum and enlarged anterior commissure. Results for both visual and tactile interhemispheric transfer tasks were normal. Dichotic listening tests showed a slight left ear advantage in both patients. These results support the hypothesis that hypertrophy of the anterior commissure is an important mechanism of functional compensation in agenesis of the corpus callosum. However, the relative subtlety of deficits in patient 1 and results of dichotic listening tests support use of other mechanisms as well. No consistent pattern of cognitive deficits was observed.

Agenesis of Corpus Callosum↗
PubMedDate not supplied

Effect of age and level of cognitive function on spontaneous and exploratory behaviors in the beagle dog.

Cognitively characterized young and aged beagle dogs were administered six different spontaneous behavior tests, which provided measures of locomotion, exploration, and social interaction. Consistent with our previous findings, we obtained no overall effect of age on locomotion. We did find, however, that for the aged dogs locomotion correlated with level of cognitive function, being lowest in age-unimpaired dogs and highest in impaired dogs. Exploratory behavior, as measured by response to novelty, varied with age, with young dogs scoring the highest. Young dogs spent more time with novel toys and a person, responded more to a silhouette of a dog, and interacted more with a model dog compared to aged dogs. Among the aged dogs, age-unimpaired dogs spent the greatest amount of time sitting or standing beside a person whereas age-impaired dogs spent the most time reacting to a reflection in a mirror. The age-impaired dogs show undirected, stereotypical types of behavioral patterns. These differences in activity patterns may be linked to underlying age-associated neuropathology.

Aging↗
PubMed1998

The effect of intervention methods on nutritional status and cognitive function of primary school children infected with Ascaris lumbricoides.

The prevalence rate of ascariasis in primary school children in northern Jakarta, Indonesia varies from 60% to 90%. An association between helminthic infection and educational achievement has long been recognized. This study was carried out in the northern part of Jakarta among primary school children 6-8 years of age. Treatment of ascariasis and health education were used as the interventions. Before the interventions, basic data on socioeconomic status, epidemiology, infection with Ascaris lumbricoides, nutritional status, and cognitive function were collected. After the interventions, only data on infection with A. lumbricoides, nutritional status, and cognitive function were collected. The children were divided into five groups. Group I was given an anthelminthic (mebendazole), group II was provided with health education, group III was given an antihelminthic and provided with health education, group IV was given a placebo (controls), and group V consisted of egg-negative children, who also served as controls. Data from 336 students were analyzed by analysis of covariance. Parasitologic examinations showed a mean prevalence rate of 58.4% for A. lumbricoides infection in the pre-intervention children and a mean prevalence rate of 40.6% in the post-intervention children. Concerning nutritional status, approximately 80% of the children showed good scores in the pre- and post-treatment data, and only a small percentage (0.9-16.2%) showed mild or moderate malnutrition. No significant difference was found between the pre- and post-treatment nutritional status. The results of the cognitive test showed that the group treated with mebendazole showed significant improvement in the Colored Progressive Matrices and Coding test. Children also showed an improvement in their learning ability, concentration, and eye-hand coordination after five months of receiving this intervention.

Antinematodal Agents↗
PubMedDate not supplied

Cognitive functioning and expressed emotion among patients with first-episode severe psychiatric disorders.

Expressed emotion (EE) in families is able to predict the clinical outcome of patients with schizophrenia and mood disorders. However, the origins of EE and its interactions with the patient's clinical characteristics are not clear. In this respect, cognitive functioning of schizophrenic and mood-disorder patients has yielded contradictory results. In this cross-sectional study, we examined a sample of 42 consecutive first-episode patients with schizophrenia-related psychoses and severe mood disorders. Forty-two relatives were interviewed with the Five-Minute Speech Sample method. The relationships between EE and 3 clusters of patient-related variables (sociodemography, performance in cognitive tests, and psychopathology) were analyzed with stepwise regression analysis. With the exception of premorbid adjustment in childhood, only the cognitive variables were significantly associated with EE after controlling for the effect of the other variables. High EE was significantly associated with good performance in cognitive tests. Our results favor the attribution hypothesis of EE instead of the hypothesis that patient psychopathology would explain EE. Good cognitive functioning may lead to higher EE scores because of the higher expectations by the relatives.

Adult↗
PubMed2001

[Severely injured patients after the initial phase--vegetative state or remaining cognitive functions?].

BACKGROUND: We wanted to quantify improvements in the subacute rehabilitation phase in patients with severe brain injuries classified as vegetative or minimal brain consciousness. MATERIAL AND METHODS: Five patients were studied during a 12 months period using a method called Coma Recovery Scale (CRS) as described by Giacino et al. (1991). The parameters measured included visual and hearing functions, motor functioning, oromotor/verbal function, communication, and arousal. The observations of the patients and commandos given were standardised in a manual, and the responses achieved from the patients were recorded according to a scale for each parameter. RESULTS: This procedure for measuring closely the progress over time in these severely brain injured patients, was used for planning a realistic rehabilitation program. It was found to be very practical in communication with relatives of the patients and with the other therapists involved. INTERPRETATION: By decomposing the cognitive functions by this method using all the available possibilities for inputs, even minimal improvement in the cognitive functions mentioned could be uncovered and recorded.

Adolescent↗
PubMed2004

Effect of slow movement execution on cognitive function.

We investigated the effect of slow paced movement on cognitive function. The task movement was a dual-task performance composed of a continuous forearm rotation for the right hand and a simple reaction task for the left hand. Exp. 1 was designed to compare reaction time during performance at a slow pace to that at medium pace by 14 female undergraduate students. The mean reaction time for the left hand under the Slow Pace was significantly longer than that under the Middle Pace condition (p < .05), which showed that the subjects were required to give more attention to right-hand performance at the slow pace as it was difficult. Exp. 2 examined changes in reaction time when using the left hand that were associated with the learning of a slow paced task while using the right hand. Twenty-three female undergraduate students participated and repeated the task 6 times. The 3 sec. prior to and the 3 sec. after each auditory stimulus were used to establish rotation speed and mean coefficients of variation. The mean coefficients of variation, evaluated as within-subject variability, showed a significantly positive correlation with reaction time at Trials 1 and 6 for prestimulus and Trials 5 and 6 for poststimulus. Over successive trials participants continued performing the primary forearm task at a constant slow pace before and after receiving auditory stimuli, and this progress was related to a decrease in reaction time. Further, the sense of concentration evaluated by the subjects poststimulus was significantly higher than that prestimulus (p < .01). Performance at a constant speed, which was much slower than the ordinary or preferred speed of each subject, may have had a strong effect on their ability to remain conscious of movement execution.

Adult↗
PubMed2003

Cognitive functioning in young and middle-aged unmedicated out-patients with major depression: testing the effort and cognitive speed hypotheses.

BACKGROUND: Cognitive deficits are common in major depressive disorder, but their nature is unclear. The effort hypothesis states that performance on effortful tasks is disproportionately impaired compared with the performance on automatic tasks. The cognitive speed hypothesis states that depression is characterized by cognitive slowness, which is a source of cognitive dysfunctioning. The present study investigated both theories in unmedicated adult depressive patients. It was also investigated whether the cognitive deficits can be attributed to more general physical illness-related factors or specifically to depressive disorder. METHOD: Thirty non-psychotic depressive out-patients were compared with 38 healthy control subjects and 25 patients with severe allergic rhinitis. The effects of group on more automatic and more effortful aspects of cognitive tasks measuring cognitive speed (Concept Shifting Task, Stroop Colour Word Test, Memory Scanning Test) and memory retrieval (Visual Verbal Learning Task, Verbal Fluency Test) were evaluated by MANCOVA. Age, sex, education and pre-morbid intelligence were treated as covariates. RESULTS: The depressive group had cognitive deficits in the automatic processing subtask of the Stroop, memory scanning and memory span. Performance on more effortful tasks was not impaired. CONCLUSIONS: Our results are more consistent with the cognitive speed hypothesis. Cognitive functioning in depressive disorder seems to be characterized by a reduced speed of information processing in automatic subtasks.

Adult↗
PubMed2001

Intracranial injection of recombinant adeno-associated virus improves cognitive function in a murine model of mucopolysaccharidosis type VII.

Mucopolysaccharidosis type VII (MPS VII) is a lysosomal storage disease caused by the lack of beta-glucuronidase (GUSB) activity. GUSB deficiency leads to the progressive accumulation of undegraded glycosaminoglycans (GAGs) in cells of most tissues, including the brain, and is associated with mental retardation. Reduction of lysosomal storage in the central nervous system and prevention of cognitive dysfunction may require intracranial delivery of a therapeutic agent during the newborn period that provides a continuous source of GUSB. Therefore, we injected recombinant adeno-associated virus encoding human GUSB into both the anterior cortex and the hippocampus of newborn MPS VII mice. Total GUSB activity in the brain approached normal levels by 18 weeks. Although GUSB activity was concentrated near the injection sites, lysosomal distension was reduced in most areas of the brain. In addition to histopathologic evidence of GAG reduction, the previously undescribed accumulation of GM2 and GM3 gangliosides in the brain was also prevented. Furthermore, GUSB expression and reduced lysosomal distension correlated with improvements in cognitive function as measured in the Morris Water Maze test. These findings indicate that localized overexpression of GUSB has positive effects on the pathology and cognitive function and does not have overt toxicity.

Animals↗
PubMed2000

Acute changes in carbon dioxide levels alter the electroencephalogram without affecting cognitive function.

The partial pressure of carbon dioxide in the arterial blood (PaCO2) is usually tightly regulated, yet it varies among healthy people at rest (range approximately 32-44 mmHg) as well as within an individual during many natural life situations. The present study examined whether modest changes in end-tidal PCO2 (PETCO2; a noninvasive measure of PaCO2) affect electroencephalographic (EEG) activity, cognitive function, and vigilance. Nine adults were ventilated mechanically using a mouthpiece; respiratory rate and breath size were held constant while PETCO2 was set to levels that produced minimal discomfort. Despite discrete changes in EEG, neither acute PETCO2 increases (mean = 47 mmHg) nor decreases (mean = 30 mmHg) from resting levels (mean = 38 mmHg) affected performance on cognitive tasks, latency or amplitude of the N1, P2, or P3 event-related potential, or alertness. Modest changes in PETCO2 may cause significant alterations in the EEG without disturbing cognitive function.

Adult↗
PubMed1991

rHuEPO treatment improves brain and cognitive function of anemic dialysis patients.

Twenty-four patients with chronic renal failure, stabilized on hemodialysis, were treated with recombinant human erythropoietin. Before treatment, all patients were anemic (mean Hct = 23.7%). Hematocrits reached normal levels (36.5%) after three months of treatment. Brain event-related potentials and neuropsychological tests were used to assess changes in brain and cognitive functions associated with the correction of anemia. Assessments were done prior to and after three and twelve months of rHuEPO treatment. The P3 component of the event-related potential increased in amplitude significantly with treatment, while its latency was unaffected. Of the four neuropsychological tests administered, scores on two improved significantly with treatment, and the other two approached significance. Taken together, these findings suggest that the correction of anemia to hematocrits near normal in uremic patients by rHuEPO treatment improves brain and cognitive function by raising levels of sustained attention, thus increasing speed and efficiency of scanning and perceptual-motor functions and enhancing learning and memory. These findings also suggest that anemia, either directly or indirectly, may impair brain function.

Anemia↗
PubMedDate not supplied

Hemodynamic changes during aging associated with cerebral blood flow and impaired cognitive function.

This study investigates the age associated changes in hemorheological properties and cerebral blood flow. Partial correlations indicate that part of the age-dependent decrease in flow velocities can be attributed to a hemorheological decrement resulting in part from enhanced oxidative stress in the aged. A possible link with Alzheimer's pathology is suggested by the augmented hemorheological impairment resulting from in vitro incubation of red cells with amyloids. These results suggest that in aging, oxidative stress as well as amyloids may influence the fluid properties of blood, resulting in a potential decrement in blood flow and oxygen delivery to the brain. Animal intervention studies further demonstrate that altered hemorheological properties of blood can actually influence cognitive function. The relationships shown to exist between hemorheology, blood flow, amyloids, oxidative stress, and cognitive function suggest that these factors may be one of the mechanisms operating in the complex etiology of Alzheimer's disease.

Adult↗
PubMed2002

Decrements in vigilance and cognitive functioning associated with ragweed-induced allergic rhinitis.

BACKGROUND AND OBJECTIVE: The adverse effects of untreated seasonal allergic rhinitis (AR) on performance in the workplace, school, and home are poorly understood. To delineate more clearly the impact and consequences of the disease on performance, the effect of symptomatic AR on vigilance and a wide range of cognitive functions was investigated. METHODS: A battery of automated neuropsychological tests was administered to asymptomatic adult subjects with histories of AR. Subjects were randomized to either a symptomatic or to an asymptomatic group. Subjects in the symptomatic group were exposed to ragweed pollen in a controlled exposure setting until they demonstrated predetermined severities of AR symptoms. Subjects in the asymptomatic group were not exposed to ragweed pollen in the environmental unit and retained a minimum symptom profile. The battery of cognitive measures was re-administered to both groups. RESULTS: AR had major adverse impacts on measures of vigilance. Further, AR adversely affected a broad range of cognitive functions. Specifically, subjects with AR symptoms demonstrated longer response times and decreased efficiency on measures of working memory, psychomotor speed, reasoning/computation, and divided attention as compared with asymptomatic subjects. CONCLUSIONS: In addition to decreased vigilance, AR was associated with decrements in speed and efficiency across several cognitive domains. This is similar to findings in research on medications and medical conditions that cause sedation. Findings may represent a link between AR and poor productivity/personal safety among AR sufferers. This suggests that these results have implications with regard to public health.

Allergens↗
PubMed1997

Absence of growth hormone effects on cognitive function in girls with Turner syndrome.

Turner syndrome (TS) is a genetic disorder characterized by short stature, gonadal dysgenesis, and a particular neurocognitive profile of normally developed language abilities (particularly verbal IQ) and impaired visual-spatial and/or visual-perceptual abilities. We have followed a large sample of girls with Turner syndrome who were enrolled in a long-term, double-blind, placebo-controlled trial of the effects of growth hormone (GH) treatment on final adult height. This study provides a unique opportunity to prospectively evaluate the effects of GH treatment on neurocognitive function in this population of girls with Turner syndrome. The GH- and placebo-treated Turner syndrome subjects were well matched for age, treatment duration, race, karyotype, and socioeconomic status. Treatment (GH or placebo) durations ranged from 1-7 yr. Whether GH deficiency and/or treatment in childhood and adolescence influences cognitive outcome in short children or GH-children is controversial. The major result of this study was the absence of GH treatment effects on cognitive function in girls with Turner syndrome. Our findings are in agreement with most of the previous studies that found no apparent growth hormone treatment effects on cognitive function in growth-hormone deficient children. We conclude that this study does not support a role for growth hormone in influencing childhood brain development in girls with Turner syndrome. Their characteristic nonverbal neurocognitive deficits were not altered with GH treatment into early adolescence.

Child↗
PubMed1998

[Motor and cognitive functions of the basal ganglia].

Basal ganglia have been known as a motor center because their lesions cause motor disturbances in involuntary movements such as chorea, ballism or akinesia in Parkinsonism. The different types of involuntary movements are closely related to the underlying muscle tone. Mechanisms of bradykinesia or akinesia have been elaborated in physiological studies on Parkinson's disease, and the significance of sensorimotor processing or attention, arousal has been disclosed as a relevant factor of bradykinesia. Cognitive functions of the basal ganglia have attracted attention, particularly in the disorder of Parkinson's disease. Subcortical dementia, difficulty in formation or changes of concepts, is encountered in advanced stages of Parkinson's disease. Whether cognitive functions in the frontostriatal system are primarily related to the motor function of the brain is an issue for future study.

Basal Ganglia↗
PubMed2006

Hyperphagia, severe obesity, impaired cognitive function, and hyperactivity associated with functional loss of one copy of the brain-derived neurotrophic factor (BDNF) gene.

The neurotrophin brain-derived neurotrophic factor (BDNF) inhibits food intake, and rodent models of BDNF disruption all exhibit increased food intake and obesity, as well as hyperactivity. We report an 8-year-old girl with hyperphagia and severe obesity, impaired cognitive function, and hyperactivity who harbored a de novo chromosomal inversion, 46,XX,inv(11)(p13p15.3), a region encompassing the BDNF gene. We have identified the proximal inversion breakpoint that lies 850 kb telomeric of the 5' end of the BDNF gene. The patient's genomic DNA was heterozygous for a common coding polymorphism in BDNF, but monoallelic expression was seen in peripheral lymphocytes. Serum concentration of BDNF protein was reduced compared with age- and BMI-matched subjects. Haploinsufficiency for BDNF was associated with increased ad libitum food intake, severe early-onset obesity, hyperactivity, and cognitive impairment. These findings provide direct evidence for the role of the neurotrophin BDNF in human energy homeostasis, as well as in cognitive function, memory, and behavior.

Adult↗