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Biomedical subjects

V Carr

Publications and source records attributed to V Carr.

At least 19 recordsLinked to original sources
PubMed1992

The effect of illness duration on perceptual asymmetry in schizophrenia.

Perceptual asymmetry in a group of schizophrenic subjects who were clinically stable and living in the community was compared with a group of normal control subjects matched for age and sex using a dichotic monitoring task of language processing. Schizophrenic subjects showed reduced target detection and slower reaction times for both left and right ear inputs. In relation to performance asymmetry, the schizophrenic subjects had a reduced speed of responding to left ear items compared to normal controls. Within the schizophrenic group differences in performance emerged according to duration of illness. Shorter duration of illness was associated with poorer target detection overall and comparatively greater magnitude of the normal right ear advantage. The latter was accounted for by a relative augmentation of the normal left ear performance decrement. These results were partly reflected in the reaction time measures. The findings suggest that as illness duration increases there may be a tendency for certain aspects of the information processing abnormality in schizophrenia to normalise, in spite of continued deficits as reflected in prolonged reaction times.

Adult↗
PubMed1992

Changes in ego defenses with recovery from depression.

This study aimed to determine whether patterns of ego defense change with short-term treatment of psychiatric illness. The subjects were 37 inpatients and outpatients with a DSM-III-R diagnosis of major depressive disorder being treated using standard clinical methods. Ego defenses before and 7 to 9 weeks after commencement of treatment were measured using a shortened version of the Defense Style Questionnaire. There was a significant decline in the use of immature defenses with symptomatic recovery, but no change in the neurotic or mature defenses. Patients with additional axis I diagnoses and/or abnormal personality traits (N = 15) used more neurotic defenses than their counterparts with major depression alone (N = 22), but this pattern did not change with time. The study demonstrates the short-term mutability of immature defenses in relation to an episode of psychiatric illness and provides empirical support for the concept of temporary regression in the context of psychiatric illness episodes.

Ambulatory Care↗
PubMed1991

AuthorBase: a database of authoring systems software.

A working prototype database of authoring system software was developed as part of a study of authoring software conducted by the National Library of Medicine. The database and development issues ranging from the scope of the database to what information to document are described. The protype demonstrates that records of reasonable integrity can be derived from vendor supplied information as long as users understand the database is only an initial starting point in searching for authoring software and a resource for becoming generally familiar with the technology.

Authorship↗
PubMed1990

Differences in dichotic listening asymmetries in depression according to symptomatology.

Subjects suffering from major depressive disorder were compared to normal controls on two verbal dichotic listening tasks. Although there were no significant differences between the groups on a task primarily of language perception, significant differences were obtained on a task with an attentional component. Overall performance was lower for the depressed group and ear asymmetry was reduced. Within the depressed group ear asymmetry varied according to symptomatology; withdrawal-retardation was associated with a lack of asymmetry and anxiety with a normal right ear advantage. The results were interpreted in terms of an interaction between affect and attention, and possible underlying mechanisms of cerebral hemisphere function were discussed.

Adolescent↗
PubMed1988

Urinary MHPG, platelet 3H-imipramine binding and symptomatology in depression: an exploratory study of clinical heterogeneity.

Urinary MHPG concentrations and platelet 3H-imipramine binding (Bmax, Kd) were measured in 20 psychiatric inpatients with diagnoses of major depressive disorder. Clinical assessments were performed using the Present State Examination (PSE) interview, and several dimensions of symptomatology were constructed on the basis of the PSE items. There was a significant positive relationship between Bmax and items reflecting both psychomotor retardation and anxiety. Urinary MHPG bore a comparatively complex nonlinear relationship to Bmax and to the psychomotor retardation symptom dimension. Urinary MHPG also showed an inverse, curvilinear correlation with certain neurotic symptoms. The implications of these findings are briefly discussed in the light of the "dysregulation" hypothesis of affective disorder.

Adult↗
PubMed1988

The dexamethasone suppression test in relation to symptomatology: preliminary findings controlling for serum dexamethasone concentrations.

A diagnostically heterogeneous sample of psychiatric inpatients (n = 52) was administered the 1 mg dexamethasone suppression test (DST) shortly after hospital admission. Each was also assessed using the Hamilton Rating Scale for Depression (HRSD) and selected items of the Present State Examination (PSE) representing psychomotor retardation and anxiety. A potent determinant of postdexamethasone serum cortisol concentrations was found to be the level of serum dexamethasone concentration achieved following the oral dose. No relationship was found between postdexamethasone cortisol concentration and the scores on either the HRSD or an anxiety scale derived from selected PSE items. However, symptoms of psychomotor retardation were significantly related to postdexamethasone serum cortisol concentration, particularly when the serum dexamethasone concentrations were taken into account. It may be that DST nonsuppression in psychiatric patients is in part a reflection of the presence of psychomotor retardation, a phenomenon that cuts across diagnostic categories.

Adolescent↗
PubMed1988

Dichotic listening asymmetries and psychotic symptoms in schizophrenia: a preliminary report.

Schizophrenic subjects were compared with both psychiatric control and normal control groups on two verbal measures of functional hemispheric asymmetry on a dichotic listening task. One measure of language perception showed little variation in ear differences across groups. However, the task that contained both attentional and language-processing components showed variations in asymmetry according to symptomatology. Subjects with high scores on scales of hallucinations and delusions showed a pattern of ear differences that was not found in those with low scores on these symptom dimensions. The results may reflect cognitive factors in a dysfunctional information-processing system and, in particular, attentional disturbance rather than anomalies in the lateralization of language.

Adolescent↗
PubMed1988

Patients' techniques for coping with schizophrenia: an exploratory study.

Non-hospitalized schizophrenic patients were administered a questionnaire designed to assess how they coped with various symptoms of their illness. Of the 200 subjects in the sample, 92 gave additional descriptions of coping techniques which they found useful in addition to those listed in the questionnaire. This report presents the latter findings and categorizes the range of coping techniques described. Patients used a variety of such techniques ranging across a spectrum of behaviour change, socialization, cognitive control and use of medical care as well as behaviours which were likely to have been identified by others as symptomatic of the illness.

Adaptation, Psychological↗
PubMed1988

The effects of antipsychotic drugs and symptomatology on perceptual asymmetry in schizophrenia.

Perceptual asymmetry was measured in acutely psychotic schizophrenic patients and normal controls using a dichotic monitoring task. Although the schizophrenic group differed from the controls in terms of accuracy and speed of response, there were no significant group differences with respect to asymmetries in these variables. The pattern of responding in the schizophrenic group was also examined in relation to differences in symptomatology and antipsychotic drug administration. These variables, in isolation and in interaction with each other, were found to have a number of effects on both asymmetry and overall level of responding. The results were interpreted in the context of an information processing model of functional hemisphere asymmetry in schizophrenia, and the implications regarding the nature of schizophrenic symptomatology and the effects of antipsychotic drugs were discussed.

Adolescent↗
PubMed1986

The effect of serum dexamethasone concentrations in the dexamethasone suppression test.

Serum dexamethasone and cortisol concentrations were measured in a sample of 98 psychiatric inpatients during the course of the 1-mg oral overnight Dexamethasone Suppression Test (DST). Suppressors were found to have significantly higher serum dexamethasone concentrations than nonsuppressors at each time of sampling (8:00 AM, 4:00 PM, and 11:00 PM). There was a significant inverse curvilinear relationship between serum dexamethasone and cortisol concentrations at each sample time. Although serum dexamethasone concentration was a potent determinant of postdexamethasone serum cortisol concentration, there were still significantly higher serum concentrations of cortisol in patients with major depression compared with patients with other disorders when dexamethasone concentrations were statistically controlled. By taking serum dexamethasone concentrations into account in defining DST suppression status, a modest increase in diagnostic specificity was achieved, but no substantial change in sensitivity.

Adult↗
PubMed1986

Dexamethasone concentrations and the dexamethasone suppression test in psychiatric disorders.

The dexamethasone suppression test (DST) has been widely used in psychiatry as a laboratory aid for the diagnosis of endogenous depression; failure to suppress serum cortisol levels is interpreted as confirming a clinical diagnosis of endogenous depression. We found that serum dexamethasone concentrations in this test vary widely and are determinants of the DST response: non-suppression of serum cortisol levels is associated with low serum dexamethasone concentrations, and suppression is associated with high concentrations.

Adjustment Disorders↗
PubMed1986

Schizophrenia: an information processing model.

There is a wealth of literature associating schizophrenia with disorders of information processing and attention. This paper draws together knowledge from experimental cognitive psychology and examines how both research findings and the clinical manifestations of schizophrenia can be accommodated by an information processing paradigm. An attentional model of schizophrenia is proposed in which disorders in the perception of information are related to dysfunction at the level of preattentive processes. This is seen as one crucial difference between schizophrenia and bipolar disorder, both of which demonstrate failures of sensory gating and filter mechanisms in the acquisition and processing of inputs. Commonalities between the two disorders are thus addressed. Certain psychopathological phenomena in schizophrenia, particularly negative symptoms ('inhibition'), hallucinations and delusions, are seen as compensatory operations of a disordered information processing system. The model has heuristic value and is able to account for, and coherently organise, the variability which continues to confound research in schizophrenia.

Arousal↗
PubMed1986

Authoring systems and assumptions about them.

More authoring systems are beginning to appear and there is greater consumer interest as microcomputers have become more widely used by less sophisticated users. Better methods are needed for evaluating systems and investigating assumptions regarding their development and use. Suggestion for selecting systems include assessing local needs, establishing familiarity through literature reviews, demonstrations, and hands on experience, applying criteria, and addressing the assumptions which motivate authoring system use. The marketplace and the technology are rapidly changing. For example, system vendors are beginning to adopt marketing efforts which are targeted toward either hardware sales, publishing, or instructional development services, instead of general audiences. Existing systems use traditional programming techniques to create conventional "frame-based" instruction, but more intelligent authoring aids are in the offing Even though the technology is advancing rapidly many of the evaluation methods and measurement problems discussed here can still be presumed to apply. They are probably more stable than the technology.

Computer-Assisted Instruction↗