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Results for “Cognitive Dysfunction”

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PubMed1999

Neuropsychological functioning in cocaine abusers with and without alcohol dependence.

Thirty codependent cocaine and alcohol users were compared with age-, education-, race-, and sex-matched cocaine abusers (N = 30) and normals (N = 30) using an extended Halstead-Reitan Neuropsychological Test Battery to determine whether cocaine abusers with alcohol dependence were more cognitively impaired than singly addicted cocaine abusers. Tests were grouped and analyzed according to 8 major ability areas. Participants who abused both cocaine and alcohol did not differ from normals on the majority of test measures. An unexpected but consistent finding was the poorer performance of the cocaine sample relative to cocaine and alcohol abusers on measures of complex psychomotor and simple motor functioning (ps < .001). Pure cocaine abusers, but not abusers of both cocaine and alcohol, also performed more poorly than normals on a measure of global neuropsychological functioning (p < .01). These results are consistent with previous reports of generally mild cognitive dysfunction in cocaine abusers. The findings also suggest that cocaine and alcohol abusers of relatively young ages may be less cognitively impaired than demographically comparable cocaine abusers. Evidence from studies of vascular functioning in abusers of cocaine and alcohol alone and in combination is discussed as possible explanation for these findings.

Adult↗

PubMed2002

Anxiety sensitivity and depression in multiple chemical sensitivities and asthma.

Patients with sensitivities to multiple chemicals report symptoms of cognitive dysfunction, respiratory distress, and mood disturbance. Lifetime and current psychiatric disorders, personality traits associated with symptom reporting, and tests of cognitive function were compared between 30 subjects with Multiple Chemical Sensitivities (MCS), 19 asthmatics, and 31 healthy controls. Relative to asthmatics and controls, more MCS subjects met criteria for current depression and somatization disorder. MCS subjects and asthmatics scored significantly higher than controls on scales of chemical odor intolerance and anxiety sensitivity, both of which were significant predictors of physical symptoms. Few differences on objective neuropsychological tests were noted. However, MCS subjects with comorbid depression performed significantly worse on a verbal memory test relative to asthmatics but not to controls. Anxiety and depression are significant contributors to the physical and cognitive symptoms of MCS subjects.

Adult↗

PubMed2006

Documenting the cognitive status of hip fracture patients using the Short Portable Mental Status Questionnaire.

AIMS AND OBJECTIVES: The aim of this study was to describe how nurses document their subjective assessment of the patients' cognitive status in the patients' records and to compare this documentation with an assessment made using a validated evaluation instrument in older patients with a hip fracture. BACKGROUND: There are indications that older people with a hip fracture and impaired cognitive ability do not receive optimal care and that they suffer from a disproportionately high number of complications. Preventing and rapidly detecting confusion is probably an effective strategy for improving care for these patients. To be able to prevent care-related complications and plan for future nursing and medical care, it is necessary to identify patients with impaired cognitive ability. DESIGN: Clinical trial including 362 patients. METHODS: The patients' cognitive function was assessed by a research nurse using a validated instrument, the Short Portable Mental Status Questionnaire, and an independent subjective assessment was made by a ward nurse. The agreement between these assessments was analysed. RESULTS: An assessment of cognitive function by the ward nurse was lacking in 12% of the patients. The assessment made by the nurses did not correspond to the level of orientation according to Short Portable Mental Status Questionnaire in 24% of the patients. In the vast of majority of these cases, the patients were documented as being cognitively alert although they were cognitively impaired according to the Short Portable Mental Status Questionnaire. Among the patients who were cognitively oriented according to the Short Portable Mental Status Questionnaire, the nurses' assessment identified 97% as oriented, but among the patients with impaired cognitive ability according to the Short Portable Mental Status Questionnaire, only 58% were identified as being cognitively impaired by the ward nurses. CONCLUSIONS: An assessment of cognitive function is still lacking in nursing records for a substantial number of older people with a hip fracture and cognitive dysfunction is frequently underdiagnosed in routine health care. RELEVANCE TO CLINICAL PRACTICE: Patient care could be improved if the patients' cognitive function was assessed regularly and objectively by means of a validated evaluation instrument.

Activities of Daily Living↗

PubMed2003

Brain structure and function in adolescents with anorexia nervosa.

Anorexia nervosa (AN) commonly arises during adolescence and is associated with significant medical morbidity. Abnormalities in brain structure and function are among the most common, early, and concerning physical consequences. Advances in neuroimaging technology have played an important role in delineating the structural and functional changes found in patients with AN. Studies using computed tomography and magnetic resonance imaging have demonstrated changes in brain structure in the low-weight stages of AN. In addition, functional neuroimaging techniques have demonstrated altered brain metabolism. Debate continues as to whether these brain abnormalities are fully reversible with weight restoration. Neuropsychological research has demonstrated that cognitive dysfunction is also a common feature of AN. Multiple studies have indicated deficits in various neuropsychological domains. Whether the reported cognitive deficits are reversible with weight gain remains unknown. To date, some preliminary evidence suggests that reported cognitive deficits in patients with AN may be associated with structural brain abnormalities. This chapter reviews the current literature about neuroimaging studies and cognitive function in adolescents with AN, discusses the possible underlying mechanisms causing these changes, and explores the possible association between them.

Adolescent↗

PubMed1998

Neuropsychological deficits in obsessive-compulsive disorder: a comparison with unipolar depression, panic disorder, and normal controls.

BACKGROUND: The neuropsychological dysfunction associated with obsessive-compulsive disorder (OCD) has similarities to the deficits reported in other affective or anxiety disorders. We directly compared cognitive function in patients with OCD with that in matched patients with unipolar depression and panic disorder and healthy control subjects to establish the specific nature of neuropsychological deficits in OCD. METHODS: Thirty patients with OCD, 30 patients with panic disorder, 20 patients with unipolar depression, and 30 controls completed a computerized neuropsychological battery that assessed the accuracy and latency of executive, visual memory, and attentional functions. RESULTS: The groups did not differ according to age, years of education, or estimated IQ. However, we found group differences in cognitive performance. The patients with OCD were impaired on measures of spatial working memory, spatial recognition, and motor initiation and execution. In contrast, performance of these tasks by patients with panic disorder or depression did not differ from that of controls. There were no group differences for performance on the measures of planning, cognitive speed, pattern recognition, and delayed matching to sample, although patients with depression were impaired for attentional set shifting. CONCLUSIONS: Neuropsychological deficits were observed in patients with OCD that were not observed in matched patients with panic disorder or unipolar depression. As such, the cognitive dysfunction in OCD appears to be related to the specific illness processes associated with the disorder.

Adult↗

PubMed1994

Impairment in memory function and neurodegenerative changes in the cholinergic basal forebrain system induced by chronic intake of ethanol.

Chronic intake of ethanol both in human and rat results in a substantial impairment in memory function associated with a reduction in the number of cholinergic neurons in the basal forebrain which give rise to the cholinergic afferentation of the cortical mantle. Degenerative changes in the basal forebrain are paralleled by the concomitant reduction of presynaptic cholinergic markers (synthesis, content and release of acetylcholine) in the neocortex and hippocampus. Cognitive dysfunction in rat induced by ethanol treatment can be ameliorated by the pharmacological manipulation of central cholinergic neurotransmission by physostigmine, arecoline or nicotine. Furthermore, fetal brain transplants rich in cholinergic neurons are able to restore cognitive function which argues in favour of a cholinergic aspect of alcohol-induced behavioural dysfunction. The observation, that implantation of purified astrocytes results in a similar restoration of learning and memory abilities associated with a recovery of cholinergic function, further indicates that behavioural sequelae of alcohol intake can largely be ameliorated by a trophic stimulation directed towards the cholinergic basal forebrain system. Regarding the cholinergic basal forebrain system as a component of the ascending reticular activation system, the involvement of the cholinergic afferentation of the cortical mantle in the mediation of memory processes and their dysfunction under neurodegenerative conditions can be explained on the basis of the "Hippocampal Memory Indexing Theory" of Teyler and DiScenna. The hypothesis is formulated in the present paper that mental dysfunction observed after chronic ethanol consumption can largely be attributed to a degeneration of the cholinergic pathway of the ascending activation system resulting in an impairment of cortical activation, clinically appearing as the "syndrome of partial cholinergic deafferentation of the cortical mantle".

Acetylcholine↗

PubMed1993

Relations of symptoms to cognitive deficits in schizophrenia.

Schizophrenia is characterized by a variety of cognitive dysfunctions. Information-processing dysfunctions differ between clinical subtypes such that nonparanoid schizophrenia patients attend less than paranoid schizophrenia patients to connotative or contextual aspects of stimuli. The positive and negative symptom dimensions are also associated with distinct cognitive deficits. In general, positive symptoms are related to auditory-processing deficits and negative symptoms to visual/motor dysfunctions. The interaction of frontal and septohippocampal brain systems, and failures of information-processing automaticity and self-monitoring, have been proposed as the bases of positive symptoms. Negative symptoms are thought to arise from abnormalities in the complex interactions of frontal and striatal systems. Recent theoretical analyses have recommended a focus on the cognitive and neuropsychological analysis of specific symptoms (e.g., hallucinations and delusions) instead of on the more heterogeneous symptom clusters or dimensions. Studies of specific symptoms indicate that patients with hallucinations have deficits in discriminating the source of information. Delusions have been related to abnormal inference processes as well as abnormal perceptual experiences. Studies should now examine the links between information-processing abnormalities and symptoms over time, as the latter change, within the framework of explicit, disconfirmable theoretical models.

Cognition Disorders↗

PubMed2004

Program to improve cognitive functioning in patients with schizophrenia: reflections.

Cognitive dysfunction in patients who suffer from schizophrenia is a major clinical problem. For such patients, the neurobiological cause(s) for the cognition deficits are not clear. Treatments with high doses of compounds that work at the coagonist site of the NMDA receptor have demonstrated that some degree of improvement can be elicited in patients. Thus, the NIMH effort to delineate the clinical responses that would allow new drugs to be registered for this use is very timely. Significant credit is due Dr. Steven Hyman and his colleagues for stimulating this bold initiative. Many problems remain to be solved to accomplish the goal. This article articulates a few such problems.

Antipsychotic Agents↗

PubMed1998

Impaired spatial working and reference memory in segmental trisomy (Ts65Dn) mice.

To evaluate the cognitive phenotype of the segmental trisomy 16 (Ts65Dn) mouse, a model of Down Syndrome (DS, trisomy 21), we assessed spatial working and reference memory using a 12-arm radial maze (RAM). Ts65Dn mice made a greater number of reference memory errors across trials compared to control mice. Both genotypes showed improvement across trials, although improvement was slower in Ts65Dn mice. Ts65Dn mice also made a greater number of working memory errors on the RAM, and in contrast to control mice, did not improve across trials, always performing at near-chance levels. These results provide evidence for both spatial working and reference memory deficits in Ts65Dn mice, characteristics of cognitive dysfunction.

Animals↗

PubMed2000

Clinical application of event-related potentials in dementing illness: issues and problems.

Many of the problems associated with the clinical application of event-related potentials (ERPs) are well recognized. These include the broad inter-subject variability of peak latencies and amplitudes in control groups, as well as the apparent non-specificity of some ERP tests. In addition, it is often the case that the same test yields a different proportion of 'hits' (in terms of identification of abnormality in patients classified by other means as having dementia) when used by different research groups. This is almost certainly due to differences in the disease state of the patients being tested. The difference between hit rates identifies another important factor which is not often considered in the application of ERP tests in clinical medicine. This is that although an ERP test may identify abnormality in the later stages of disease, the true task for the test is to identify abnormality in early disease when evidence of cognitive dysfunction will be different and less frank than in later stages of the disorder. It is therefore, necessary to identify the cognitive deficits associated with the early stages of dementia and devise appropriate ERP tests to detect these deficits. A recent paper by Fox et al. (Fox, N.C., Warrington, E.K., Seiffer, A.L., Agnew, S.K., Rossor, M.N., 1998. Presymptomatic cognitive deficits in individuals at risk of familial Alzheimer's disease. A longitudinal prospective study. Brain 121, 1631-1639.) suggests that ERP tests of verbal memory function may be the most sensitive for detecting the early stages of Alzheimer's disease.

Cognition Disorders↗

PubMed1999

Internal consistency, temporal stability and neuropsychological correlates of three cognitive components of the Positive and Negative Syndrome Scale (PANSS).

Comprehensive models of schizophrenia have increasingly included symptoms of cognitive dysfunction as an important feature of schizophrenia. Factor analytic studies of the Positive and Negative Syndrome Scale (PANSS) have consistently established cognitively disorganized symptoms as a separate domain from positive and negative symptoms. However, the individual symptom composition of the cognitive domain varies from model to model. The present study explores the temporal stability, internal consistency, concurrent validity, and discriminant validity for three published PANSS factor analytically derived cognitive components (Bell et al., 1994a, Psychiatry Res., 52, 295-303; Dollfus et al., 1991. Eur. Psychiatry, 6, 251-259; Kay and Sevy, 1990. Schizophr. Bull., 16, 537-544). Analyses were conducted using PANSS data from 120 patients with DSM-IV diagnoses of schizophrenia or schizoaffective disorder. Results indicate that the Bell et al. and Kay and Sevy models have similar psychometric properties including adequate temporal stability, internal consistency, and discriminant validity. The Kay model demonstrated somewhat better concurrent validity with cognitive test measures, while the Dollfus model demonstrated relatively poor psychometrics. The symptom composition of a narrowly defined cognitively disorganized subtype and a more broadly defined cognitively impaired subtype are discussed in terms of their value for schizophrenia research.

Adult↗

PubMed2004

Neuropsychological sequelae of obstructive sleep apnea-hypopnea syndrome: a critical review.

Obstructive sleep apnea-hypopnea syndrome (OSAHS) is a well-recognized clinical sleep disorder that results in chronically fragmented sleep and recurrent hypoxemia. The primary daytime sequelae of the disorder include patient reports of excessive daytime sleepiness, depression, and attention and concentration problems. It has been well established that OSAHS negatively impacts certain aspects of cognitive functioning. The primary goals of this article are to (1) clarify the pattern of cognitive deficits that are specific to OSAHS; (2) identify the specific cognitive domains that improve with treatment; and (3) elucidate the possible mechanisms of cognitive dysfunction in OSAHS. At the conclusion of the paper, we propose a potential neurofunctional theory to account for the etiology of cognitive deficits in OSAHS. Thirty-seven peer-reviewed articles were selected for this review. In general, findings were equivocal for most cognitive domains. Treatment, however, was noted to improve attention/vigilance in most studies and consistently did not improve constructional abilities or psychomotor functioning. The results are discussed in the context of a neurofunctional theory for the effects of OSAHS on the brain.

Attention↗

PubMed2005

Effects of ischemia-reperfusion on NMDA receptor subunits 2a and 2b level in rat hippocampus.

The authors investigated the effects of ischemia and reperfusion on the N-methyl-D-aspartate receptor (NMDAR) subunits 2A and 2B concentration in rat hippocampus. At the protein level, significant increase in the amounts of NMDAR 2A and NMIDAR 2B in the rat hippocampus was observed at 1 h after reperfusion compared with control group. These results suggested that the alteration in hippocampal NMDAR2 subunit concentrations after ischemia-reperfusion might be invovlved in cognitive dysfunction and excitotoxicity.

Animals↗

PubMed2000

Supplementation with L-histidine during dietary zinc repletion improves short-term memory in zinc-restricted young adult male rats.

Zinc, an essential dietary element, modulates neurotransmission in brain regions associated with cognition. Cognitive dysfunction has been reported in offspring of female rats fed zinc-restricted diets during gestation and/or lactation. Studies on the cognitive effects of zinc restriction during young adulthood are limited. After a 3-wk period of dietary zinc restriction, male rats (71-75 d old) were repleted with zinc chloride alone, or zinc chloride supplemented with L-histidine, and short-term memory was measured using the Morris water maze. During restriction, zinc-restricted rats demonstrated significantly longer (86.0%) retrieval latencies than nonrestricted controls, and significantly lower liver (25.5%), bone (32.5%) and hippocampal (3.2%) zinc concentrations. During subsequent repletion, rats repleted with zinc chloride supplemented with L-histidine improved their retrieval latencies to the extent that they were no longer significantly different from controls by repletion d 3. This was associated with a return of hippocampal zinc concentrations to control values by repletion d 3. The mean retrieval escape latencies of the zinc chloride-repleted rats remained significantly prolonged (75.0%). Collectively, these data indicate the following: 1) feeding a zinc-restricted diet for 3 wk impairs short-term memory in young adult male rats, and 2) repletion with dietary zinc supplemented with L-histidine improves short-term memory function more efficiently than dietary zinc chloride alone. The latter point suggests that dietary zinc supplemented with L-histidine is more bioavailable to the brain than zinc provided as zinc chloride alone. These findings are important in that they highlight the importance of both dietary zinc formulation and the use of functional assessments in determining zinc nutriture.

Analysis of Variance↗

PubMed2005

Neuropsychologic functioning and health status in systemic lupus erythematosus: does ethnicity matter?

BACKGROUND: Despite increased severity of lupus in blacks, including more frequent neuropsychiatric manifestations, there is sparse data on neuropsychologic function in black patients with lupus. METHODS: Neuropsychologic functioning and health-related variables were examined among blacks (n = 34) and whites (n = 14) fulfilling American College of Rheumatology criteria for systemic lupus erythematosus. RESULTS: Blacks and whites performed comparably on measures of verbal and visual memory, working memory, and motor speed after controlling for estimates of premorbid cognitive ability. Blacks trended towards poorer performance on specific attention/processing speed measures. Pain, fatigue, depression, anxiety, physical and emotional well-being were unrelated to ethnicity. Blacks exhibited a trend towards greater impairment of physical functioning. Ethnicity-related differences in overall damage, noncognitive neuropsychiatric manifestations, and prevalence of nephritis revealed greater severity among blacks. CONCLUSIONS: Initial differences in premorbid cognitive function possibly contribute to disparate clinical outcomes, including a greater proportion of blacks exhibiting subnormal neurocognitive performance. Blacks evidencing lower premorbid ability may be at greater vulnerability for poorer functional outcomes (eg, coping skills, medical compliance and employment) if they experience disease-related cognitive dysfunction.

Adult↗

PubMed2004

Cognitive impairment in euthymic bipolar patients: implications for clinical and functional outcome.

OBJECTIVE: Cognitive impairment in bipolar disorder may be a stable characteristic of the illness, although discrepancies have emerged with regard to what dysfunctions remain during remission periods. The aim of this study was to ascertain whether euthymic bipolar patients would show impairment in verbal learning and memory and in executive functions compared with healthy controls. Secondly, to establish if there was a relationship between clinical data and neuropsychological performance. METHODS: Forty euthymic bipolar patients were compared with 30 healthy controls through a battery of neuropsychological tests assessing estimated premorbid IQ, attention, verbal learning and memory, and frontal executive functioning. The effect of subsyndromal symptomatology was controlled. RESULTS: Remitted bipolar patients performed worse than controls in several measures of memory and executive function, after controlling for the effect of subclinical symptomatology, age and premorbid IQ. Verbal memory impairment was related to global assessment of function scores, as well as to a longer duration of illness, a higher number of manic episodes, and prior psychotic symptoms. CONCLUSIONS: Results provide evidence of neuropsychological impairment in euthymic bipolar patients, after controlling for the effect of subsyndromal depressive symptoms, suggesting verbal memory and executive dysfunctions. Cognitive impairment seems to be related to a worse clinical course and poor functional outcome.

Adult↗

PubMed1997

Cognition and mood in systemic lupus erythematosus. Evaluation and pathogenesis.

Cognitive dysfunction is frequent in SLE, probably related to primary underlying immune/inflammatory mechanisms operating in the brain. Longitudinal studies relating patterns of cognitive impairment to putative pathogenetic factors would provide evidence for this hypothesis. Such studies could also lead to more specific therapeutic interventions to ameliorate or reverse brain compromise in SLE.

Affect↗

PubMed2004

Aging enhances vascular dysfunction induced by the Alzheimer's peptide beta-amyloid.

Aging is a major risk factor for Alzheimer's disease and the evidence suggests a role for cerebrovascular pathology in cognitive dysfunction. The hypothesis in this study is that aging is a significant risk factor in the effect of the Alzheimer peptide beta-amyloid on endothelium-dependent function of cerebral and peripheral vessels. The diameter response to acetylcholine, an endothelium-dependent vasodilator, was recorded in pressurized segments of rat posterior cerebral vessels from mature (3 months) and aged (20 months) rats. The threshold concentration of beta-amyloid for a significant decrease in the response to acetylcholine was lower in vessels from aged rats (10(-9) M) than in vessels from mature rats (10(-8) M). The threshold concentration of beta-amyloid for a significant decrease in the sensitivity to acetylcholine was lower for ring segments of aorta from aged rats (10(-10) M) than for aorta from mature rats (10(-8) M). Structural changes of the endothelium were first observed in electron micrographs of aorta from aged rats when the concentration of beta-amyloid was 10(-8) M, whereas structural changes in aorta from mature rats did not occur until the concentration of beta-amyloid was increased to 10(-7) M. The results suggest that aging increases the susceptibility of cerebral and peripheral blood vessels to beta-amyloid related dysfunction and that functional change precedes structural change.

Acetylcholine↗