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Cognitive function and language of a child with an arachnoid cyst in the left frontal fossa.

The authors inspected the cognitive function of a boy with a congenital arachnoid cyst in the left frontal fossa. Neuropsychological tests described his cognition, including language, memory, and frontal functions, as mildly retarded overall. The boy's verbal ability was delayed, but his frontal function was intact. We supposed that the cyst would not affect his cognitive function. SPECT images showed low perfusion in the left temporal lobe. Dysfunction of the left temporal lobe should cause delayed language leading to learning difficulty. Neuropsychological evaluation of cognitive function concurrent with rCBF imaging was necessary not only for describing the influence of the cyst but also in discriminating its psychological aspects.

Arachnoid Cysts↗

Clinical analysis of cognitive function in diabetic patients by MMSE and SPECT.

We examined the frequency of cognitive impairment using the mini-mental-status examination (MMSE), as well as cerebral perfusion using single photon emission computed tomography (SPECT) in elderly diabetic patients. Written consent was obtained from all patients prior to their inclusion in this study. An MMSE score of 26 or less was adopted as an indication of cognitive impairment. Following an initial study, a 3-month study incorporating the use of MMSE and SPECT was performed in subjects, some of whom were taking donepezil hydrochloride. Of the 92 subjects enrolled in this study, 38% exhibited cognitive functional impairment and 18% earned MMSE scores of 23 or lower that were indicative of dementia. With regard to their cerebral blood flow pattern as determined by SPECT 217, 31.4 and 34.2% of subjects showed parieto-temporal hypoperfusion, asymmetrical hypoperfusion and fronto-temporal hypoperfusion patterns of abnormalities, respectively; 11.4% displayed unclassifiable findings and 8.5% showed no detectable abnormalities. No significant differences were seen in patients that were taking donepezil hydrochloride compared to those who were not. The incidence of cognitive functional impairment in elderly, diabetic patients was significantly elevated and was accompanied by a reduction in cerebral blood flow in the fronto-temporal region, as determined by SPECT.

Aged↗

Effects of rivastigmine on cognitive function and quality of life in patients with schizophrenia.

We aimed to determine whether the cholinesterase inhibitor rivastigmine, an inhibitor of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE), would improve quality of life and cognitive function in 16 clinically stable subjects affected by schizophrenia in the residual phase. Study subjects began rivastigmine treatment at a dose of 1.5 mg bid. This dose was escalated at monthly intervals in increments of 1.5 mg bid to a maximum of 6 mg bid. All subjects were followed for 12 months. Quality of life was assessed using the Satisfaction with Life Domains Scale (SLDS, a self-report scale containing 10 "satisfaction" items); cognitive function, attentional function, and aspects of learning and memory were evaluated using common neuropsychological tests. Psychopathology was evaluated by means of the Brief Psychiatric Rating Scale (BPRS). Rivastigmine treatment resulted in significant improvements in quality of life, which were paralleled by significant improvements in cognitive function, learning and memory, and trends for improvement in attention. The BPRS factor "anergia" showed significant improvement, while low baseline scores in other psychotic factors did not permit further improvements. There were no reports of nausea or vomiting. In conclusion, rivastigmine significantly improved quality of life in subjects with schizophrenia. These benefits may relate to the drug's effects on cognitive deficits and negative symptoms associated with the condition.

Adolescent↗

Sensory-motor and cognitive functioning in children who have undergone bone marrow transplantation.

Sensory-motor and cognitive functioning was investigated in a group of 32 children treated with bone marrow transplantation (BMT), 1-6 years after treatment. Twenty-five of the patients had suffered from leukemia. The BMT procedure had involved a regimen of cytostatic drugs and, for leukemia patients, total body irradiation at a dose of 10 Gy, administered in one session. Cytostatic drugs and irradiation are known to be potentially neurotoxic, particularly when combined. The examination involved four neuropsychological tests of sensory-motor and cognitive functioning, as well as an age-appropriate intelligence test. For control the bone marrow donors (n = 32), siblings of the patients, were also investigated. A pronounced delay in motor development was found in four children, who had been treated with BMT including total body irradiation before 3 years of age. Patients between 3 and 11 years of age at BMT were at a slight disadvantage, compared to donors, on tasks involving perceptual and fine motor speed. In older patients no deficits were observed.

Adolescent↗

Lateralization of olfactory cognitive functions: effects of rhinal side of stimulation.

This study investigated differences in olfactory cognitive functions, in 40 healthy young right-handed participants, with respect to side of rhinal stimulation. The targeted functions were: perceived familiarity, episodic recognition memory, free identification and repetition priming in identification. The results showed that odors presented to the right nostril were rated as more familiar than odors presented to the left nostril and also showed significant effects of repetition priming in identification. However, no differences were found between nostrils in episodic recognition memory or free identification. These latter results indicate a rather extensive inter-hemispheric interaction in higher-order cognitive functions.

Adult↗

Effects of subcortical cerebral infarction on cortical glucose metabolism and cognitive function.

BACKGROUND: The mechanism of dementia in subcortical cerebral infarction is incompletely understood. OBJECTIVE: To determine how cognitive function is related to cortical metabolism in patients with subcortical infarction and a continuum of cognitive impairment. METHODS: We used positron emission tomography (PET) and the glucose metabolic tracer fludeoxyglucose F 18 to study 8 patients with subcortical stroke and normal cognitive function (S-CN), 5 patients with subcortical stroke and cognitive impairment (S-CI) who did not have dementia, 8 patients with subcortical stroke and dementia (S-D), and 11 controls with no cognitive impairment or stroke. A subset of patients had absolute regional cerebral metabolic rate of glucose (CMRglc) determined, while in all subjects regional tracer uptake normalized to whole brain tracer uptake was calculated. PET data were analyzed by constructing volumes of interest using coregistered magnetic resonance imaging data and correcting the PET data for atrophy. RESULTS: Global CMRglc was significantly lower in the patients with S-D than in the control and S-CN groups, with S-CI rates intermediate to those of the S-D and S-CN groups. Absolute regional CMRs of glucose were similar in the S-D and S-CI groups and in the control and S-CN groups. The regional pattern, however, showed lower right frontal regional CMRglc ratios in all stroke groups compared with the controls. There were modest correlations between performance on the Mini-Mental State Examination and whole brain CMRglc when all 4 groups were included. CONCLUSIONS: These results demonstrate that subcortical infarction produces global cerebral hypometabolism, which is related to the clinical status of the patients. In addition, specific frontal lobe hypometabolism also appears to be a feature of subcortical infarction. Taken together, both global and regional effects on cortical function mediate the production of clinical symptoms in patients with subcortical strokes.

Aged↗

Care for demented patients in different living conditions. Effects on cognitive function, ADL-capacity and behaviour.

OBJECTIVE: To assess if and how demented patients' living conditions affect their level of functioning. DESIGN: A prospective concurrent control-study. SETTING: Sundsvall, an industrial community in the middle of Sweden. PARTICIPANTS: Forty-six demented patients in group-living (GL-group) and 62 controls (C-group). MAIN OUTCOME MEASURE: Cognitive function, ADL-capacity and behaviour were measured every third month during one year. RESULTS: Both groups deteriorated, but the decline was significantly slower in the GL-group regarding some ADL-functions, e.g. dressing and motor functions, whereas some behavioural disturbances were significantly more frequent in the GL-group. No differences were observed regarding the level of cognitive function. CONCLUSION: The living condition has small effects on cognitive function and ADL-capacity. The behavioural disturbances observed in GL should be the focus of future research.

Activities of Daily Living↗

The measurement of cognitive function during acute hypoglycaemia: experimental limitations and their effect on the study of hypoglycaemia unawareness.

The risk of hypoglycaemia and the resulting impairment in brain function are major factors preventing those with diabetes achieving normoglycaemia. The need to define these risks more precisely has prompted an increasing research effort to identify which aspects of cerebral function are particularly vulnerable and at which glucose level. Much of the evidence is inconsistent, reflecting not only the wide range of methods for measuring cognitive function and inducing hypoglycaemia, but also the inherent variability of the response. Nevertheless, the data suggest that those mental activities which are relatively undemanding are often unaffected at all levels of experimental hypoglycaemia while the performance of more complex tasks deteriorates at glucose concentrations of around 3 mmol l-1. The relative imprecision of cognitive testing is reflected in the debate which surrounds the pathogenesis of hypoglycaemia unawareness. There is some evidence that the glycaemic threshold for autonomic activation and symptoms can vary while the threshold for cognitive impairment is fixed. This has led to the hypothesis that hypoglycaemia unawareness arises when the autonomic response develops at a blood glucose below that for impaired cognition, thus preventing patients from recognizing or responding to their usual symptoms. However, contradictory data suggest that the threshold for cognitive impairment can alter in line with the autonomic response, a conclusion which falls to fit either the above hypothesis or the clinical description of hypoglycaemia unawareness. These differences may be methodological or relate to the relative imprecision of measurements of cognitive function. Resolution of these discrepancies may have to await the development of advanced technology such as high resolution MRI or PET scanning. In the meantime, progress could be made if all groups agreed on a limited range of cognitive function tests and used them in a standardized manner.

Attention↗

Blood pressure and cognitive function in an African-American and a Caucasian-American sample: the Maine-Syracuse Study.

OBJECTIVE: The primary purpose of this study was to examine associations between indices of blood pressure (BP) and cognitive function for African-American participants in the Maine-Syracuse Longitudinal Study (MSLS). Corresponding data for the Caucasian-American MSLS participants were included to provide a basis for comparison. Interactions of age with BP indices were also assessed in relation to cognitive function. METHODS: Data were drawn from the baseline MSLS questionnaires, medical interviews and examinations, Wechsler Adult Intelligence Scale subtests, and measurements of BP for 1563 participants, of whom 147 were African American. Multiple linear regression analyses were employed to examine the relationship between several BP predictors and cognitive outcomes with statistical adjustment for demographic, psychosocial, and cardiovascular risk factors. RESULTS: Significant inverse associations between BP indices and cognitive performance were obtained for both racial cohorts but were generally of higher magnitude for the African-American cohort. Interactions of BP with age were not obtained for any of the cognitive test scores. CONCLUSIONS: Elevations in BP are associated with poorer cognitive function for African-American and Caucasian-American cohorts. These associations are similar for younger and older participants.

Adolescent↗

Putamen FDOPA uptake and its relationship tot cognitive functioning in PD.

Impaired executive functioning is frequently found in PD patients. As a result, impairments in the executive components of other cognitive functions such as memory, visuo-spatial functions and fluency are also present. From a neuroanatomical point of view, different loops are mediating cognitive, emotional and motor functions. The putamen is part of the motor loop, while the caudate nucleus is part of the motor loop but also of the cognitive loop. In PD, multiple neurotransmitter systems are involved in cognitive functioning, including the dopaminergic system. Cognitive functioning in PD is related to striatal FDOPA uptake. This is particularly true for the caudate nucleus, but also for the putamen. We found a relationship between putaminal FDOPA uptake and measures for executive functioning, memory and fluency in a group of 28 non-demented advanced PD patients. This is a surprising finding since the putamen is part of the motor loop, but not the cognitive loop. One possible explanation is that the putamen is involved in motor actions after cognitive switching and is therefore related to neuropsychological test scores, as these require motor responses.

Fluorine Radioisotopes↗

Cognitive function predicts first-time stroke and heart disease.

OBJECTIVE: To investigate whether impaired cognitive function is an early manifestation of vascular injury in the brain and therefore predicts risk of subsequent cardiovascular disease. METHODS: The study population consisted of 12,096 middle-aged participants in the Atherosclerosis Risk in Communities (ARIC) Study who had no history of stroke or coronary heart disease (CHD) at the time of cognitive testing. Cognitive function was measured using the Digit-Symbol Substitution Test (DSST), the Word Fluency Test, and the Delayed Word Recall Test. Cognitive test scores were adjusted for demographic factors and then evaluated as predictors of incident cardiovascular events using Cox proportional hazards analysis. RESULTS: Over a median follow-up period of 6.4 years, there were 516 incident cardiovascular events (292 myocardial infarctions, 50 CHD deaths, and 174 strokes), resulting in an average annual incidence rate of 0.7%. Lower adjusted scores on each cognitive test predicted a greater risk of incident cardiovascular events after controlling for established vascular risk factors (highest vs lowest quartile DSST, adjusted hazard ratio 1.56, 95% CI 1.23 to 1.97, p for linear trend by quartile < 0.001). The magnitude of the association was comparable with other commonly used predictors of vascular risk such as left ventricular hypertrophy on EKG and high-density lipoprotein cholesterol level of <35 mg/dL. CONCLUSION: Cognitive test scores below demographic norms predict incident cardiovascular disease in middle-aged subjects independently of established vascular risk factors.

Cognition Disorders↗

Brain somatostatin: receptor-coupled transducing mechanisms and role in cognitive functions.

In recent years there has been an increased interest in understanding the role of somatostatin in the brain. This review summarizes the current knowledge of the anatomical distribution of somatostatin and its receptors, the receptor-coupling mechanisms and the somatostatinergic modulation of cognitive functions. Somatostatin is also highly concentrated in the extra-hypothalamic areas of the brain, including the frontal and parietal cortex and the hippocampus. At these locations somatostatin may play a fundamental role in the modulation of cognitive functions. Activation of somatostatin receptors in the brain results in an inhibition of adenylate cyclase enzyme activity, reduction in intracellular Ca2+ levels and hypopolarization of cells by inducing outward K+ currents. Biological studies on the effects of increased brain somatostatin showed a facilitation in learning behavioural tasks, while brain somatostatin depletion by cysteamine caused memory loss. These observations, along with the severe somatostatinergic neurotransmission impairment demonstrated in Alzheimer's patients, strongly suggest a fundamental role for somatostatin in the modulation of cognitive functions.

Animals↗

Cognitive function in candidates for coronary artery bypass graft surgery.

BACKGROUND: While many studies have investigated cognitive impairments in patients after coronary artery bypass graft surgery, very few have closely evaluated presurgical cognitive functioning of bypass candidates. METHODS: A battery of neuropsychologic tests was administered to a consecutive series of patients listed for bypass surgery (n = 109). Cognitive function of bypass candidates was compared with that of a healthy control group (n = 25) and published test norms. RESULTS: Cognitive test scores in candidates for bypass were significantly lower than those of the control group on tests of attention, information processing speed, and verbal memory. Additionally, bypass candidates' cognitive test scores were significantly reduced compared with expected values derived from validated test norms, on all but one cognitive test. CONCLUSIONS: Cognitive performances of candidates for bypass were significantly lower than those of a healthy control group and published cognitive test norms.

Aged↗

Selective non-response to clinical assessment in the longitudinal study of aging: implications for estimating population levels of cognitive function and dementia.

OBJECTIVE: to identify the cognitive outcome of interviewed participants who did not progress to partake in clinical assessments in a longitudinal aging study. DESIGN: a retrospective study was conducted on participants who were interviewed but who did not complete the clinical assessment (including an extended cognitive assessment) at either Wave 1 or both Wave 1 and Wave 3 of the Australian Longitudinal Study of Ageing. A total of 1947 participants aged 70 and older commenced the study, 246 participants without clinical data at either or both Waves 1 and 3 were identified for the sub-sample followed-up retrospectively. The Informant Questionnaire for Cognitive Decline in the Elderly (IQCODE) was administered to informants and medical records were reviewed. RESULTS: participants who did not complete the clinical assessment at Wave 3 reported poorer health and had poorer cognitive function at Wave 1 independent of age and gender. Rates of possible dementia or cognitive decline were higher in the group who did not undertake the clinical assessment compared with both those who did the clinical assessment and with population data. CONCLUSION: selective non-response to clinical assessment in a longitudinal aging study is associated with higher risk of cognitive decline and probable dementia. Longitudinal aging studies may underestimate rates of dementia and population levels of cognitive decline.

Aged↗

Conversion from preclinical to dinical stage of Alzheimer's disease as shown by decline of cognitive function in carriers of the Swedish APP-mutation.

The characterisation of the borderline syndrome between normal cognitive function and Alzheimer's disease (AD), often mentioned as Mild Cognitive Impairment (MCI) has been a goal for recent research. However, a variety of definitions of MCI-like syndromes and the uncertainty about the final diagnosis have hampered progress. To overcome these problems, the present study will describe cognitive function in two healthy mutation carriers and two matched non-carriers of the Swedish double mutation family, during the time period when carriers convert to a symptomatic stage, i.e., true preclinical AD, and finally into the stage when a clinical diagnosis of AD is first possible. The findings question the generality of common MCI concepts and the commonly held beliefs about cognitive features in late preclinical stage of AD.

Alzheimer Disease↗

[Can age-dependent cognitive functions be measured? P300 potentials--concept of brain aging--early diagnosis of dementia processes].

Event related P300 potentials as the electrophysiological substrate of cognitive functions, such as the stimulus processing time (P300 latencies) and visual attention capacity (P300 amplitudes) are suitable for the analysis of age-related changes in cognitive human brain functions. P300 investigations carried out in a total of 330 test subjects aged between 18 and 98 years, showed an overall slight prolongation of the P300 latencies by 10 ms for each decade, as well as a discrete reduction in the P300 amplitudes of 1 microV. To describe the relationship between the P300 parameters and chronological age, polynomial regression models are more suitable than linear functions. This means that in middle-age, P300 potentials change only slightly while, from about the age of 60 upwards, a noticeable acceleration in the P300 changes takes place. An interesting observation was the fact that the acceleration in the P300 latency increase occurred some 10 years earlier in women than in men, beginning in the early postmenopausal period. The polynomial course of the regression function for the age-dependence of P300 potentials might reflect the positive influence of socio-cultural factors on the aging of cognitive functions. The true extent of the age-related changes in cognitive functions, however, can be determined only with the aid of intra-individual longitudinal studies. This is of considerable importance for the early diagnosis of both metabolic and primarily degenerative encephalopathies.

Adolescent↗

Exploring developmental change in the neural bases of higher cognitive functions: the promise of functional magnetic resonance imaging.

The dramatic changes in cognitive ability observed throughout childhood mirror comparably significant changes in the developing brain. Studies of animals provide important data on associations between the development of behavior and the neural substrate. However, understanding the development of brain-behavior relations for higher cognitive functions in humans requires direct, concurrent measurement of behavior and brain functions in the children themselves. To date, such data have been very limited. Recent developments in functional magnetic resonance imaging (fMRI) provide the opportunity to systematically explore the development of brain-behavior relations in children. In this article we consider the potential of fMRI to contribute to researchers' understanding of the development of brain-behavior relations. We begin with an overview of the basic imaging method. We then review work from our own laboratory that demonstrates systematic patterns of association between performance on visuospatial tasks and patterns of brain activation, and we compare our findings with those from other laboratories focused on other cognitive domains. Finally, we discuss the potential impact of functional imaging on researchers' understanding of core issues in cognitive and brain development.

Adolescent↗

Growth, growth hormone and cognitive functions.

The interactions among short stature, growth hormone (GH) and cognitive functions have been extensively studied so far. However, although it seems well established that short stature is associated with cognitive problems, little effort has been made to point out the presence of specific psychological effects related to the different forms of short stature. In 'short normal' children, the presence of a scholastic underachievement seems to suggest that short stature 'itself' might predispose these patients to some of their psychosocial difficulties. The higher incidence of academic failure, in presence of a normal intellectual functioning, has been attributed to environmental and psychosocial factors, including over-protective parents and low self-esteem resulting from the impact of short stature. These problems appear to be common also to other forms of short stature (such as Turner's syndrome) where, however, they are frequently associated with other specific deficits. The in vivo model which might allow, at least in part, better understanding of GH (per se)-dependent effects is represented by GH deficiency (GHD), in which, however, the specific role of GH on psychological functioning is frequently masked by the presence of associated hormonal deficiencies. Children with isolated GHD are reported to have specific educational deficits, in particular learning disability and attention-deficit disorders, which have been tentatively attributed to a compromised intellectual potential. The psychological effects of long-term GH treatment in children with GHD still remain controversial, with some retrospective studies describing a generally beneficial outcome. Since early experiences in school are closely related to success in adult life, the possible implications that GHD during childhood holds during adulthood have been recently considered. Although regional differences have been observed in subgroups of adults with GHD, it seems that these patients have normal cognitive functions and educational attainment, but are more likely to be unemployed (and unmarried) than members of the general population. In general, patients with GHD, who have been treated at centers where psychological counselling was an integral part of the treatment program, seem to be better adjusted in adult life. For these reasons, a multidisciplinary treatment approach could allow early detection of problems in academic achievement and psychosocial development in patients with short stature, being immediately able to provide the appropriate educational and counselling interventions.

Adult↗