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In an investigation of the relationship between the reflection-impulsivity cognitive dimension and short-term memory in emotionally disturbed children, 42 Ss were administered the Matching Familiar Figures Test and the Visual-Aural Digit Span Test. Analysis of covariance indicated that on all memory tasks the reflective Ss were better than the impulsive subjects.
The possible modulation by D1 drugs of learning abilities of a population of aged memory-impaired animals was investigated in the present study. The level of D1/[3H]SCH 23390 receptors was first examined by quantitative autoradiography to ascertain if cognitive deficits seen in these animals could be related to alterations in the levels of these receptors. No significant differences in [3H]SCH 23390 binding were observed in any of the brain areas examined between young, and aged memory-unimpaired and aged memory-impaired animals. However, the cognitive deficits of the aged-impaired rats were modulated by D1 drugs. The D1 agonists SKF 38393 and SKF 81297 (3.0 mg/kg, i.p.) significantly reduced the latency period to find a hidden platform in the Morris Water Maze, reflecting improved cognitive functions, while the D1 antagonist SCH 23390 (0.05 mg/kg, i.p.) had no overall significant effect. Moreover, the D1 agonist SKF 38393 increased, whereas the antagonist inhibited, in vivo hippocampal acetylcholine release. Taken together, these results suggest that functional hippocampal acetylcholine-dopamine interactions exist in aged memory-impaired rats. More importantly, the cognitive deficits seen in the aged-impaired rats can be attenuated by stimulations of D1 receptors, hence suggesting an alternative approach to alleviate the cognitive deficits seen in the aged brain.
In a population unselected for aerobic fitness status, aerobic fitness (VO2max) and its interaction with age were used to predict performance on several cognitive measures known to be affected by chronological age. It was hypothesized that, in particular, cognitively demanding tasks would be sensitive to aerobic capacity. Healthy subjects between 24 and 76 yr of age (N = 132) were recruited from a larger study into determinants of cognitive aging (Maastricht Aging Study-MAAS). All participants took part in a submaximal bicycle ergometer protocol and an extensive neurocognitive examination, including tests of intelligence, verbal memory, and simple and complex cognitive speed. Participants engaged more hours a week in aerobic sports and felt healthier than the nonparticipants of the same age did. No group differences were found in the basic anthropometric characteristics height, weight, and BMI. Two of four subtasks that reflect complex cognitive speed (Stroop color/word interference and Concept Shifting Test) showed main and interaction effects with age of aerobic capacity in a hierarchical regression analysis, accounting for up to 5% of variance in parameter score after correction for age, sex, and intelligence main effects. These findings fit well within a moderator model of aerobic fitness in cognitive aging. They add to the notion that aerobic fitness may selectively and age-dependently act on cognitive processes, in particular those that require relatively large attentional resources.
OBJECTIVE: Previous research has demonstrated an association between alexithymia and a deficit in interhemispheric communication in Vietnam combat veterans with posttraumatic stress disorder. The purpose of this study was to evaluate this association in a nonclinical sample. METHODS: The efficiency of interhemispheric transfer was assessed in 14 alexithymic and 15 nonalexithymic right-handed, male, undergraduate university students using a tactile finger localization task. RESULTS: The nonalexithymic subjects were significantly more efficient at transferring information between the cerebral hemispheres than the alexithymic subjects. CONCLUSIONS: This finding provides further evidence of an interhemispheric transfer deficit in alexithymia and suggests that an alexithymic cognitive style reflects poor integration of the information processing of the two cerebral hemispheres.
OBJECTIVE: We examined potential early markers of schizophrenia using measures of formal thought disorder in offspring of parents with schizophrenia, other mental illness and no mental illness. METHODS: Two blind raters coded formal thought disorder in adolescent/early adult offspring of 42 schizophrenic, 39 other mental illness, and 36 no mental illness parents. In addition to parental diagnosis, we compared the individual offspring diagnosis with severity of formal thought disorder. Within the schizophrenia, other mental illness and no mental illness offspring groups, we examined the relationship between severity of formal thought disorder and performance on cognitive and motor tasks. RESULTS: There were no statistically significant differences in formal thought disorder by parent or offspring diagnoses. Within the offspring group of parents with schizophrenia, the subjects with higher formal thought disorder scores performed significantly worse on the cognitive battery than those with lower formal thought disorder scores. Offspring of the other mental illness group with higher formal thought disorder scores, however, showed more deficits on motor tasks than those with lower formal thought disorder scores. CONCLUSION: Formal thought disorder may reflect underlying cognitive dysfunction in the offspring of parents with schizophrenia. Motor dysfunction in the offspring of parents with other psychiatric illness might be associated with formal thought disorder.
BACKGROUND: Health of the Nation Outcome Scales (HoNOS) have been developed to measure of outcomes in people with mental health problems. AIMS: The particular physical and cognitive problems affecting older people requires a specific scale for their measurement. We describe the development of such a scale, named HoNOS 65+. METHOD: Pilot, validity and reliability studies were carried out on an amended scale. Validity was assessed by comparison with existing scales reflecting depression, cognitive function, psychiatric symptomatology, activities of daily living and functional abilities. Reliability was measured in two centres. RESULTS: HoNOS 65+ was successfully amended to include specific aspects of mental health problems in older people including the phenomenology of depression, delusions occurring in the presence of dementia, incontinence and agitation/restlessness. HoNOS 65+ was able to discriminate between people suffering from organic and functional illnesses. Correlations with other scales indicated reasonable validity. Reliability was satisfactory. CONCLUSIONS: Aversion of HoNOS 65+ is presented (see pp. 435-438, this issue) which is appropriate for use in elderly people with mental health problems.
Studies of scalp-recorded brain event-related potentials in humans currently depend on the electronic averaging of many responses to the stimulus. In non-averaged single responses, it is sometimes possible to see late components such as the so-called P300, but not the shorter latency components that are much smaller and masked in background noise. We tried to identify short-latency cognitive potentials evoked by finger stimulation by comparing single trial responses that are concomitantly recorded at the contralateral and ipsilateral parietal scalp respectively. We developed a single trial topographic mapping method that proved important for assessing whether any left-right difference at short latency indeed reflected genuine cognitive electrogeneses. These results make it possible to analyze on a trial-by-trial basis the short latency cognitive processing in somatic perception.
Choline acetyltransferase activity and cognitive domain scores of Alzheimer's patients. Item scores from the Mattis Dementia Rating Scale (MDRS) and the Mini-Mental State Examination (MMSE) from 389 patients with probable Alzheimer's disease were submitted to principal component analysis with orthogonal rotation. The optimal solution identified four factors that reflected the cognitive domains of attention/registration, verbal fluency/reasoning, graphomotor/praxis and recent memory. A subgroup of patients was identified for whom both the MDRS and the MMSE had been administered within the 12 months before death. Scores were assigned to these patients for the four factors. These cognitive-domain scores were then correlated with postmortem choline acetyltransferase (ChAT) activity in the medial frontal cortex, inferior parietal cortex, and hippocampus. ChAT activity in both the medial frontal and the inferior parietal cortex significantly correlated with scores on the graphomotor/praxis factor. Medial frontal ChAT also correlated significantly with the attention/registration scores. Hippocampal ChAT correlated significantly only with recent memory scores. These results are consistent with current animal research regarding the effect of selective cholinergic lesions on behavior.
Cognitive decline, commonly first recognized as memory impairment, is a typical feature of Alzheimer's disease (AD). Neuropathological changes in the cerebral cortex and limbic system lead to deficits in learning, memory, language, and visuospatial skills. The precise nature of cognitive dysfunction reflects the distribution of pathological changes in AD. These will vary along the disease severity continuum and may also depend on where the disease sits in the spectrum of dementia. For example, AD-related disorders such as Lewy body dementia (LBD) and Parkinson's disease dementia (PDD) also show symptoms of cognitive decline and share several pathological features, including degeneration of cortical cholinergic and striatal dopaminergic neurons. In vascular dementia (VaD), there is often an unequal distribution of cognitive deficit, with severe impairment in some functions and relative sparing of others. Cholinesterase (ChE) inhibitors, which help restore acetylcholine levels in the brain, are licensed for the symptomatic treatment of AD and have shown additional benefit in related dementias. Physiological correlates of cholinergic function/dysfunction in the brain include regional cerebral blood flow, glucose metabolism, and cerebrospinal fluid levels of ChE enzymes. These variables represent valuable markers of the clinical efficacy of ChE inhibitors. However, direct assessment of cognitive improvement, stabilization or decline is usually considered the key efficacy parameter in clinical studies of ChE inhibitors in AD and related dementias. Large-scale, placebo-controlled clinical studies of ChE inhibitors have demonstrated efficacy in treating the cognitive impairments associated with AD. Randomized comparative studies of ChE inhibitors are now under way to directly compare symptomatic efficacy and effects on disease progression. Clinical trial data of the cognitive effects of ChE inhibitors in AD, LBD, PDD, and VaD are discussed in detail in this article. The benefits of long-term treatment on symptomatic improvement in cognition and further potential disease-modifying effects are highlighted.
To obtain objective measures of possible impairment due to organic solvents, auditory, visual and somatosensory evoked potentials and cognitive event related potentials were recorded in a group of 13 workers occupationally exposed to a mixture of various solvents. The patients were compared to healthy subjects and to chronic alcoholics seen during post-alcohol withdrawal. Auditory and visual evoked potentials were almost normal but somatosensory evoked potentials showed a slight decrease of peripheral conduction velocities and an increase of central conduction times more marked in the solvent exposed workers who were also alcoholics. The late "cognitive" components reflecting attention processes (N2 and P3) were normal. Solvent-exposed workers and alcoholics were both characterized by some difficulty in modulating their attentional resources according to task demands, as reflected by a tendency to responses (N1, N2 and P3) of similar amplitudes whether the stimulus was or was not the target. These findings support the presence, in solvent exposed workers, of minor dysfunction of the nervous system at both peripheral and cortical levels potentiated by alcohol as well as of mild cognitive impairments concerning attention processes.
Stress and the development of a (schizophrenic) psychosis are inextricably related. The process by which stress actually affects psychosis is far less clear. The hypothalamic-pituitary-adrenal system, and in particular the release of corticosteroids, has been attributed an essential role. However, schizophrenia is a disorder in which many functions are distorted. Dysfunctions can be found in behavior, cognition, coping, physiology, pituitary-adrenal and immune functioning. In this short paper, these functions are discussed as to how they contribute to the way stress is appraised and processed. Schizophrenic patients are impaired in their biological response to stress by showing a blunted cortisol response to psychosocial stress. It is hypothesized that this reflects rather cognitive dysfunction, based on biological dysfunctions in those brain structures that are responsible for these processes, i.e. the prefrontal cortex and the limbic system. Considering the blunted cortisol response as a maladaptive stress response, its consequences are commented on with an emphasis on the immune system. Finally, the role of neuroleptics, and in particular the atypical ones, is discussed for their beneficial effect, beyond their fear-and anxiety-reducing properties, in restoring some of the cognitive dysfunctions schizophrenic patients display. By doing so, they may improve perception of the environment, enhance adjustment and thus a proper stress response. Integration of these processes in stress research described, may provide new vistas of the stress concept in schizophrenia.
The literature on chronic diseases recognizes the role of illness cognition as a mediator between stress and illness. Few conceptualizations and instruments, however, give an indication of both unfavorable and favorable ways of adjusting to an uncontrollable long-term stressor, such as a chronic disease. The authors propose 3 generic illness cognitions that reflect different ways of reevaluating the inherently aversive character of a chronic condition: helplessness as a way of emphasizing the aversive meaning of the disease, acceptance as a way to diminish the aversive meaning, and perceived benefits as a way of adding a positive meaning to the disease. A self-report instrument, the Illness Cognition Questionnaire, was developed to assess these cognitions across different chronic diseases. The results support the reliable and valid assessment of these illness cognitions in patients with rheumatoid arthritis and multiple sclerosis and indicate the maladaptive function of helplessness and the adaptive function of acceptance and perceived benefits for the long-term physical and psychological health of patients with a chronic disease.
A cognitive theoretical perspective toward emotional distress and behavior disorders is described and then applied to developing both a classification of emancipation problems and a plan for intervention. Problems described include over-dependency, vacillation about dependency, and resistance to authority. The plan for intervention minimizes complications that a vigorously confrontive method often intensifies with adolescents. Instead, it entails accurate reflection of cognitions and thereby capitalizes on anti-expectation.
Event-related potentials (ERPs) were recorded during a continuous recognition memory task for visually presented words, with a 6 item lag between the first and second presentation of each word. The subjects consisted of: (i) a control group of patients with primary generalized epilepsy; (ii) patients who had undergone either a left or a right anterior temporal lobectomy; (iii) unoperated patients with either left or right unilateral temporal lobe epilepsy. In the controls, ERPs to detected 'old' words were reliably more positive-going in the interval 300 to 600 ms post-stimulus than were ERPs to 'new' items. In both left and right lobectomy patients, 'old/new' ERP differences in the same latency range were significantly smaller than in the controls, and did not differ significantly from zero. At midline electrodes, old/new effects in the temporal lobe epilepsy patients were of similar magnitude to those of the controls. In contrast to the control data, the old/new effects in the temporal lobe epilepsy patients were asymmetric, in that they were smaller over the hemisphere ipsilateral to the seizure focus than over the contralateral hemisphere. No relationship was found across subjects between the magnitude of old/new ERP effects and verbal memory performance. In a second task, occasional non-words had to be discriminated against a background of sequentially presented words, some of which were repetitions of the immediately preceding item. ERPs evoked by repeated words were more positive-going than were those to first presentations; this effect was reliable, and of equivalent size, in all patient groups. It is concluded that in the recognition task, old/new ERP effects are dependent on temporal lobe functioning, but that the anterior temporal lobe is not the principal locus of the generators of these effects. The cognitive processes reflected by these effects do not appear to be strongly lateralized to one hemisphere, and neither do they seem to be necessary for normal verbal memory.
Social skills training has focused on 'performance' or overt behaviour, rather than on the other components of successful social functioning: motivation and goals, analysis of social information, and performance feedback, Some basic aspects of this 'analysis' or 'social cognition' component were compared in a preliminary study of 25 teenagers and young adults with severe learning difficulties, whose social interaction was categorized as either 'impaired' or 'appropriate'. As predicted from the literature on autistic children, there were no differences between the groups on tasks involving recognition of the visual aspects of the concept of self or perceptual role-taking. It is suggested that social impairments do not reflect social cognitive abilities which are 'lower level' (i.e. can be solved on the basis of information available to the senses). Contrary to expectations, on the four individual tasks of affective role-taking, which is 'higher level', since it requires inferences to be made about the inner emotional state of another person, the differences between the groups were not significant. However, the results were in the predicted direction, and when scores on the tasks were combined, the overall performance of the socially impaired group was significantly poorer (P less than 0.05). It is suggested that the results from this aspect of social cognition might be attributed either to methodological difficulties or to differences between autistic children and the present sample. The clinical implications of the findings of the study are discussed.
Lack of insight or impaired awareness of deficits in patients with dementia is a relatively neglected area of study. The aim of this study was to evaluate insight in a group of demented patients with two assessment scales and to assess their relationship with the cognitive level of disease severity. Sixty-nine consecutive patients affected by Alzheimer's disease (n = 37) and vascular dementia (n = 32) with a wide range of cognitive impairment (MMSE = 17.0 +/- 6.4) were recruited. Insight was evaluated with the Guidelines for the Rating of Awareness Deficits (GRAD)--specifically targeted to memory deficits--and the Clinical Insight Rating scale (CIR), evaluating a broader spectrum of insight (reason for the visit, cognitive deficits, functional deficits, and perception of the progression of the disease). In the whole sample, GRAD and CIR were significantly associated with MMSE (Spearman's coefficient = .51, p < .001; and r = -.55, p < .001) and with Clinical Dementia Rating scale (-.57, p < .001; and r = .57, p < .001) respectively. The shape of the relationship of MMSE with CIR and GRAD scales was assessed with spline smoothers suggesting that the relationship follows a trilinear pattern and is similar for both scales. Insight was uniformly high for MMSE scores > or = 24, showed a linear decrease between MMSE scores of 23 and 13, and was uniformly low for MMSE scores < or = 12. The trilinear model of the association between insight and cognitive status reflects more closely the observable decline of insight and can provide estimates of when the decline of insight begins and ends.
Neurobiological and cognitive models of unconscious information processing suggest that subconscious threat detection can lead to cognitive misinterpretations and false alarms, while conscious processing is assumed to be perceptually and conceptually accurate and unambiguous. Furthermore, clinical theories suggest that pathological anxiety results from a crude preattentive warning system predominating over more sophisticated and controlled modes of processing. We investigated the hypothesis that subconscious detection of threat in a cognitive task is reflected by enhanced "false signal" detection rather than by selectively enhanced discrimination of threat items in 30 patients with panic disorder and 30 healthy controls. We presented a tachistoscopic word-nonword discrimination task and a subsequent recognition task and analyzed the data by means of process-dissociation procedures. In line with our expectations, subjects of both groups showed more false signal detection to threat than to neutral stimuli as indicated by an enhanced response bias, whereas indices of discriminative sensitivity did not show this effect. In addition, patients with panic disorder showed a generally enhanced response bias in comparison to healthy controls. They also seemed to have processed the stimuli less elaborately and less differentially. Results are consistent with the assumption that subconscious threat detection can lead to misrepresentations of stimulus significance and that pathological anxiety is characterized by a hyperactive preattentive alarm system that is insufficiently controlled by higher cognitive processes.
This study investigated the production of different types of speech pauses and repairs in the story narratives produced by autistic, mentally retarded, and normal children, matched on verbal mental age. Ten children in each group were asked to tell the story depicted in a wordless picture book. The narratives were analyzed for frequency of grammatical (between phrase) and nongrammatical (within phrase) pauses, and for several measures of story length and complexity. The main results were that children with autism produced significantly fewer nongrammatical pauses, and that their nongrammatical pausing was correlated with measures of story length and complexity. These findings suggest that the stories told by the autistic children reflect reduced cognitive and communicative demand. The implications of this study for future research on the use of a variety of prosodic characteristics as measures of social cognitive deficit in autism are discussed.