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PubMed2003

Improvement in cognitive function after radical excision of an anterior skull base meningioma--a report of 2 cases.

It has been well documented that memory difficulties in patients with anterior skull base meningioma may improve after tumour resection. However, there have been few reports on studies where precise testing of cognitive function has been conducted before and after surgery. Here we report 2 cases of anterior skull base meningioma where 2 tests of cognitive function, the Wechsler adult intelligence scale-revised (WAIS-R) and the Wechsler memory scale-revised (WMS-R), were performed by the patient before and after surgical treatment. After the operation there was a dramatic increase in the performance IQ as measured by the WAIS-R. In addition, the scores for both the "Attention/Concentration" and the "Delayed Recall" subsets of the WMS-R scale improved. There were differences between the 2 patients in the length of time required for functional recovery and this was thought to be due to the tumour size and the age of the patient. The use of these scales would enable physicians who are treating patients with anterior skull base meningioma to assess the recovery time that is likely to be needed before full return of cognitive function after surgery.

Adult↗

PubMed1993

Meticulous prevention of hypoglycemia normalizes the glycemic thresholds and magnitude of most of neuroendocrine responses to, symptoms of, and cognitive function during hypoglycemia in intensively treated patients with short-term IDDM.

To test the hypothesis that hypoglycemia unawareness is largely secondary to recurrent therapeutic hypoglycemia in IDDM, we assessed neuroendocrine and symptom responses and cognitive function in 8 patients with short-term IDDM (7 yr) and hypoglycemia unawareness. Patients were assessed during a stepped hypoglycemic clamp, before and after 2 wk and 3 mo of meticulous prevention of hypoglycemia, which resulted in a decreased frequency of hypoglycemia (0.49 +/- 0.05 to 0.045 +/- 0.03 episodes/patient-day) and an increase in HbA1c (5.8 +/- 0.3 to 6.9 +/- 0.2%) (P < 0.05). We also studied 12 nondiabetic volunteer subjects. At baseline, lower than normal symptom and neuroendocrine responses occurred at lower than normal plasma glucose, and cognitive function deteriorated only marginally during hypoglycemia. After 2 wk of hypoglycemia prevention, the magnitude of symptom and neuroendocrine responses (with the exception of glucagon and norepinephrine) nearly normalized, and cognitive function deteriorated at the same glycemic threshold and to the same extent as in nondiabetic volunteer subjects. At 3 mo, the glycemic thresholds of symptom and neuroendocrine responses normalized, and surprisingly, some of the responses of glucagon recovered. We concluded that hypoglycemia unawareness in IDDM is largely reversible and that intensive insulin therapy and a program of intensive education may substantially prevent hypoglycemia and at the same time maintain the glycemic targets of intensive insulin therapy, at least in patients with IDDM of short duration.

Adult↗

PubMed2002

Study of cognitive function among the Adult Health Study (AHS) population in Hiroshima and Nagasaki.

Although neuropsychological dysfunction is found among A-bomb survivors exposed in utero as it is among patients who receive central nervous system radiotherapy, neuropsychological examinations have not been conducted on the survivors. Its prevalence may be increased as a result of the increased rate of strokes reported among those exposed to a high radiation dose. In this study, we examined the effects of radiation exposure on cognitive function among adult survivors in the Adult Health Study (AHS). The study subjects were men and women born prior to September 1932 who had undergone biennial examinations during the period 1992-1996 in Hiroshima or 1993-1998 in Nagasaki. We evaluated cognitive performance for 3,113 subjects with the Cognitive Abilities Screening Instrument (CASI), and we examined the relationship between cognitive performance and potentially related factors (sex, age, city where the subjects were exposed, years of education, and radiation dose). In contrast to exposure to radiotherapy, exposure to atomic bomb radiation had no apparent effect on cognitive function. Factors that did affect cognitive function were age, sex, city and years of education. Further investigation, including examination of other neurological functions, is required before a final conclusion regarding radiation-induced neurological dysfunction can be reached.

Adult↗

PubMed1996

Spine update. Impaired cognitive functioning after whiplash injury of the cervical spine.

To enhance the awareness of physicians treating whiplash patients, findings from previous research regarding cognitive functioning of these patients are discussed and recommendations for assessment provided. Cognitive disturbances (i.e., deficient attentional functioning and impairment of memory) are frequent complaints in patients after whiplash injury. However, few prospective studies of nonselected patients have been performed. These studies indicate that impaired cognitive functioning relates either to trauma-induced somatic symptoms (i.e., pain) or psychologic symptoms resulting from problems adjusting to trauma-related somatic symptoms. Accordingly, cognitive disturbances after whiplash show a fair rate of recovery, which parallels recovery from trauma-related somatic symptoms. Current research does not indicate disturbances in higher cognitive functions after whiplash.

Brain Injuries↗

PubMed2001

Serum dioxin and cognitive functioning among veterans of Operation Ranch Hand.

We used the Halstead-Reitan neuropsychological test battery, the Wechsler adult intelligence scale-revised, the Wechsler memory scale, and the wide range achievement test to assess cognitive functioning among Air Force veterans exposed to Agent Orange and its contaminant, 2,3,7,8-tetrachlorodibenzo-p-dioxin (dioxin), during the Vietnam war The index subjects were veterans of Operation Ranch Hand (N = 937), the unit responsible for aerial herbicide spraying in Vietnam from 1962 to 1971. A comparison group of other Air Force veterans (N= 1,052), who served in Southeast Asia during the same period but were not involved with spraying herbicides served as referents. Cognitive functioning was assessed in 1982, and dioxin levels were measured in 1987 and 1992. We assigned each Ranch Hand veteran to the background, low, or high dioxin exposure category on the basis of a measurement of dioxin body burden. Although we found no global effect of dioxin exposure on cognitive functioning, we did find that several measures of memory functioning were decreased among veterans with the highest dioxin exposure. These results became more distinct when we restricted the analysis to enlisted personnel, the subgroup with the highest dioxin levels. An analysis based on dioxin quintiles in the combined cohort produced consistent results, with veterans in the fifth quintile exhibiting reduced verbal memory function. Although statistically significant, these differences were relatively small and of uncertain clinical significance.

2,4,5-Trichlorophenoxyacetic Acid↗

PubMed2000

Is there epidemiologic evidence that anti-oxidants protect against disorders in cognitive function?

Experimental studies have identified several pathways through which oxidative stress could adversely affect cognitive function and increase the risk for dementia. Anti-oxidant supplements have been proposed as interventions for secondary or primary prevention against dementia. The existing observational studies and randomized trials examining anti-oxidants and cognitive function outcomes are reviewed. A discussion is provided of methodologic limitations of existing studies and possible directions for future investigations.

Aging↗

PubMed1999

[Premature birth and cognitive functioning in adolescence].

Premature infants are considered a high-risk population for developing cognitive dysfunction. Studies have indicated lower cognitive performance among elementary school children born prematurely. We focused on cognitive functioning of such adolescents. This age was chosen because of its critical importance in the development of the individual. 50 adolescents aged 14-16 years born prematurely were compared with 50 born at full-term and matched for gender, age and socioeconomic status. All subjects attended regular schools and did not suffer severe neurological disorders. Cognitive functioning was measured by the Bender-Visual Motor Gestalt Test and by 3 subtests from the Wechsler Intelligence Scale for Children (revised WISC-R test). Results revealed that prematurely born adolescents scored lower than those born at term on all measures of cognitive performance. The results are discussed in terms of their developmental meaning and of therapy for the prematurely born.

Adolescent↗

PubMed1996

[Cognitive functions of school children with normal IQ and histories of severe and early malnutrition].

This is a cross section study designed to evaluate the long lasting consequences of early and severe undernutrition on the development of basic cognitive functions. Attention, memory and problem-solving capacity were assessed in a group of 16 school children, who were severely undernourished during the first two years of age. They were compared with a group of 16 children with a normal growth. All subjects, age 8 to 10, had a normal intellectual coefficient and they belonged to the me same socioeconomical level. Memory was measured with a modified version of subtest of digits from WISC; attention was evaluated with a modified version of the Continuous Performance Task and problem-solving was measured with the Anstey Domino Test. A personal computer was used to assess the cognitive functions. The children who were undernourished during infancy presented lower scores in memory (number of the digits) and in problems solving (number of correct answers). They also had a worse performance than the control group in the same response time, when attention was evaluated. These results suggest that early severe undernutrition had deletereous effects on basic cognitive functions.

Attention↗

PubMed1997

Immediate recovery of cognitive functions and resolution of fatigue by treatment with weak electromagnetic fields in a patient with multiple sclerosis.

Cognitive deficits are common among patients with multiple sclerosis (MS). The pathogenetic mechanisms underlying the cognitive impairment in MS are unknown and there is presently no effective therapeutic modality which has shown efficacy in improving cognitive deficits in MS. A 53 year old college professor with a long history of secondary progressive MS experienced, over the preceding year, noticeable deterioration in cognitive functions with difficulties in short and long term memory, word finding in spontaneous speech, attention and concentration span. Unable to pursue his academic activities, he was considering early retirement. Mental examination disclosed features of subcortical and cortical dementia involving frontal lobe, left hemispheric and right hemispheric dysfunction. Almost immediately following the extracerebral application of AC pulsed electromagnetic fields (EMFs) of 7.5 picotesla intensity and a 4-Hz sinusoidal wave, the patient experienced a heightend sense of well being, which he defined as enhancement of cognitive functions with a feeling "like a cloud lifted off my head." He reported heightend clarity of thinking and during the application of EMFs he felt that words were formed faster and he experienced no difficulty finding the appropriate words. His speech was stronger and well modulated and he felt "energized" with resolution of his fatigue. There was improvement in manual dexterity and handwriting and testing of constructional praxis demonstrated improvement in visuospatial, visuoperceptive and visuomotor functions. It is suggested that some of the cognitive deficits associated with MS, which are caused by synaptic disruption of neurotransmitter functions, may be reversed through pulsed applications of picotesla range EMFs.

Cognition Disorders↗

PubMed1989

Antiepileptic drugs, cognitive function, and behavior in children.

In conclusion, it should be repeated that behavioral and cognitive functions in children with epilepsy, as in adults, represent the outcome of multifactorial processes. However, interest has been growing in the role of anticonvulsant drugs as an important variable. Studies in adults have clearly shown the impact of these drugs on both cognitive function and behavior, and the beneficial effects of achieving monotherapy, especially with carbamazepine, have been noted. Extrapolation of these results to children would seem reasonable, and there is some evidence in the literature to support this conclusion. Data in children, however, are complicated by several confounding factors. These include the status of the child under investigation; for example, children with a pre-existing behavior disorder appear to be more susceptible to developing grossly disturbed behavior with medications such as phenobarbital, as opposed to those who at pretreatment assessment do not display abnormalities. Mentally retarded children may be another group specifically susceptible to developing problems with medications. The effect of the anticonvulsant drug on seizure frequency is a complicating variable in interpretation of many investigations: in some patients improvement of seizures leads to improved behavior, while in others the opposite occurs. In some children, behavior exacerbations appear to be provoked by the sudden cessation of seizures, which may occur, for example, in forced normalization associated with barbiturates or benzodiazepines. Serum level monitoring is often not possible in childhood studies because of ethical considerations, and interpreting pharmacokinetic interactions from mere knowledge of orally prescribed agents is hazardous.(ABSTRACT TRUNCATED AT 250 WORDS)

Anticonvulsants↗

PubMed2006

A 3-day estrogen treatment improves prefrontal cortex-dependent cognitive function in postmenopausal women.

Estrogen secretion in young women follows a cyclic pattern characterized by a pronounced surge in estrogen around ovulation. The way in which this estrogen peak affects cognitive functioning is unclear. Short-term estrogen treatment for a few days mimicking normal pre-menopausal estrogen dynamics substantially enhanced cognitive functions in ovariectomized animals. Here, we provide evidence that inducing a single estrogen peak in postmenopausal women improves their cognitive abilities. Healthy women (51-64 yrs, n=14) received either 100 microg estrogen transdermally for 3 days or placebo in a double-blind within-subject design. The treatment caused a temporary rise in serum estrogen levels roughly comparable to the mid-cyclic changes in estrogen in young women. At the end of the treatment, the women completed two types of tests involving primarily hippocampus-dependent functions of memory retention or prefrontal cortex-dependent functions. Results revealed a clear beneficial effect of estrogen on tasks mainly involving the prefrontal cortex: performance on a digit-ordering task (p<0.05) and on a task requiring short-term memory of event sequences in an unfamiliar story (p<0.01) were improved, and susceptibility to interference in the Stroop test (p<0.05) was diminished after estrogen. On the other hand, estrogen did not affect hippocampus-dependent retention of a story, with delayed recall tested after 30 min or 1 week, although immediate recall was improved by estrogen. We conclude that in postmenopausal women, a transient increase in plasma estrogen concentration acutely improves prefrontal cortex-dependent cognitive functions, whereas hippocampus-dependent memory retention is less affected. Our results encourage future studies to investigate whether repeated induction of short-lasting estrogen peaks could enhance cognitive efficacy of hormonal replacement therapy.

Administration, Cutaneous↗

PubMed2005

Alzheimer's disease and depression: preclinical comorbidity effects on cognitive functioning.

Both Alzheimer's disease (AD) and depression (D) are prevalent disorders in old age and may co-occur in the same individual. The present study examined whether a diagnosis of D in AD has negative effects on cognitive functioning in the preclinical stage of the diseases, as well as at the time when the diagnoses were rendered. Population-based samples of 13 individuals with incident AD and D, 109 incident AD cases without D, and 179 normal older adults were followed over a three-year period. The groups were compared preclinically and at the time of diagnosis on global cognitive functioning using the MMSE total and the specific item scores, as well as the occurrence of depressive symptoms. As expected, there were clear AD-related deficits preclinically, which were exacerbated at follow-up. In addition, there were D-related deficits on three MMSE items (i.e., following commands, reading, and writing). The poorer performance on the three MMSE items was linked to an elevation of depressive symptoms. However, D was not associated with greater decline in cognitive functioning over the three-year follow-up period. Thus, although depressive symptoms may result in slight cognitive deficits in preclinical AD, at the time of the dementia diagnosis these effects may be absorbed by the neurodegenerative process.

Aged↗

PubMed1992

[The effect of dihydroergocristine on cognitive functions and sleep in elderly subjects].

The aim of this study was to assess the effect induced by the dopamine agonist dihydroergocristine (DHEC, CAS 17479-19-5), whose memory-improving activity is well-known, on sleep pattern and cognitive function, and the possible relationship between them. Ten elderly volunteers were included in the study. Selected subjects had to be neither demented nor depressed, according to neuropsychodiagnostic criteria (SCAG < 30, Hachinski dementia score < or = 15, Hachinski ischemic score < 6, HRSD < or = 22). All subjects underwent a nightly polysomnographic evaluation during placebo, after single and long-term once-daily 6 mg DHEC administration. Cognitive function and attention were also assessed by the Randt memory test and WAIS digit-symbol subtest. DHEC caused a marked and significant increase in the acquisition subitem, and memory improvement was documented during DHEC treatment. A significant direct relationship between the effect of DHEC on REM sleep and memory test was also evidenced. Our results confirmed the role of REM sleep in the restoration of cognitive function.

Aged↗

PubMed2005

Assessment of a modified Mini-Mental Scale for cognitive functions in children.

This study was conducted to standardize a clinical test to assess cognitive functions in children between 3-14 years and to evaluate its use in patients with encephalopathy. We included 50 children in Group A with non-neurological illness. Another 50 children were included in Group B with encephalopathy due to varied etiologies. The Mini Mental State Examination (MMSE) used in adults was modified, using tests from standardized assessment tools previously used in Indian children. It was administered independently by two observers at admission and after a few days in the two Groups. In Group A, the mean and SD of the score in various age groups were calculated. Sensitivity and specificity of the test in predicting poor outcome with a cut-off score of 10 was calculated at admission and after a mean of 4 days. The average time taken for the test was 6.03 minutes. No significant interobserver variability was found. Cut off abnormal scores calculated as 2 SD below mean in different age groups were 3 to 5 years 24, 6 to 8 years 28, 9 to 11 years 30, 12 to 14 years 35. In children with encephalopathy a score below 10 predicted poor outcome with a sensitivity of 35 percent and specificity of 100 percent at admission. Retest after 4 days had sensitivity and specificity of 68 percent and 100 percent respectively. We conclude that the modified Child MMSE may be used as a screening test to assess and monitor cognitive functions in children.

Adolescent↗

PubMed1996

Estimation of vitamin needs--riboflavin, vitamin B6 and ascorbic acid-according to blood parameters and functional-cognitive and emotional indices in a selected well-established group of elderly in a home for the aged in Israel.

OBJECTIVE: To evaluate the vitamin status and the effects of micronutrient supplementation as determined by biochemical assays and functional, cognitive and emotional tests in a selected well-established group of elderly people, average age above 80 years. METHODS: Dietary consumption was evaluated by in-person interview using a food frequency questionnaire. Medical, biochemical, nutritional, functional, cognitive and behavioral parameters were assessed in elderly subjects (n = 12) living in a home for the aged, at baseline and after 42 days of micronutrient supplementation. The same parameters were assessed in additional subjects (n = 9), at baseline only. RESULTS: In all subjects, most of the micronutrients were not supplied at an adequate level. Supplementation of micronutrients at a level of 100% RDA improved parameters related to vitamin status, the activation coefficients (AC) of GR (glutathione reductase) and AST, blood ascorbic acid concentrations, functional-cognitive evaluation values, blood pressure, pulse rate, and serum cholesterol and triglycerides levels. At baseline, the following parameters significantly correlated with vitamin intake and were used for the estimation of vitamin needs: AC of GR, Tinetti Balance Evaluation, FIM and recorded morbidity. CONCLUSIONS: On the basis of limited available data, calculation of vitamin needs based on regression lines resulted in estimates (mg/day) of: > 150 for ascorbic acid, > 3 for riboflavin, > 3 for vitamin B6. Expanding the current practice of supplementing micronutrients at a level of 100% RDA (in tablet form) that already exists in some elderly societies should be considered after a comprehensive study in a large group of elderly people.

Aged↗

PubMed2002

The relationship of hypertension in the elderly to AD, vascular dementia, and cognitive function.

BACKGROUND: Hypertension at the age of 45 to 50 years may predispose to AD later in life. It is not known whether hypertension after age 65 years also contributes to AD risk, and its effect on cognitive function is also not fully understood. METHODS: Data were analyzed from 1,259 Medicare recipients free of dementia in a longitudinal study covering a 7-year period (1991 to 1998). The effect of hypertension was first examined in relationship to the risk for incident AD and then to incident vascular dementia (VaD) using Cox proportional hazards models. Changes in performance over time on tasks of memory, language, and visuospatial/cognitive function were compared in those with and without hypertension using generalized estimating equations. RESULTS: Of the 1,259 subjects, 731 (58.1%) had a history of hypertension associated with diabetes, stroke, and heart disease. A history of hypertension was not associated with an increased risk for AD (rate ratio [RR] 0.9, 95% CI 0.7 to 1.3) but was associated with an increased risk for VaD (1.8 [1.0 to 3.2]). Hypertension was not associated with changes in memory, language, and general cognitive function in normal individuals over time. Compared with individuals with neither hypertension nor heart disease, those with hypertension or heart disease alone had no increase in risk for VaD. However, when both were present, there was a threefold increase in risk for VaD. A sixfold increase in risk was observed when both hypertension and diabetes were present. CONCLUSIONS: Hypertension after age 65 years is not associated with AD and does not adversely affect memory, language, or general cognitive function. A history of hypertension may be an antecedent to VaD, particularly in the presence of heart disease or diabetes.

Aged↗

PubMed2004

[Cognitive function in patients with endometrial and colorectal cancer: connection with hormonal and metabolic status].

Cognitive dysfunction may be associated with the presence of an array of hormono-metabolic factors of risk for certain basic noninfectious diseases, supposedly, including cancer. The investigation was concerned with an appraisal of such cognitive functions as verbal and eye memory and ability to concentrate in endometrial and colorectal cancer patients versus hormonometabolic status and relevant parameters in menopausal women. The indices of short-term memory and concentration in endometrial carcinoma were significantly higher than both in colorectal cancer and osteoporotic patients. However, they were not among healthy women of the same age. A whole range of relationships between said indices and glucose- and estradiol levels in blood serum of patients was studied. No link was established between blood-serum cholesterol, b-lipoproteide and insulin concentration in patients, on the one hand, and cognitive function, on the other. Further research is expected to disclose the ties of the latter with other hormono-metabolic factors as well as tumor-related stress.

Aged↗

PubMed1987

Magnetic resonance imaging and cognitive functioning in multiple sclerosis.

The relationship between cognitive impairment in multiple sclerosis and brain lesions seen on magnetic resonance imaging (MRI) was studied. Three groups of 11 patients with multiple sclerosis, matched for the variables of disability, duration of illness, age and sex, were included. On the basis of neuropsychological testing, the groups were seen to differ in their level of cognitive impairment. The first group showed no cognitive impairment, the second group a moderate, and the third group a serious cognitive impairment. These differences between the groups were reflected by MRI, which revealed more abnormalities in the groups with cognitive impairment compared with the group with normal cognitive function. However, by MRI it was not possible to distinguish between the groups with moderate and that with serious cognitive impairment.

Adult↗