PubMed Health⌕ Search

Biomedical subjects

J P Chapman

Publications and source records attributed to J P Chapman.

At least 19 recordsLinked to original sources
PubMed1992

Monaural and binaural story recall by schizophrenic subjects.

P. Green and other investigators have reported that schizophrenic Ss have poorer recall of stories presented to both ears than to the single best ear (binaural deficit) and poorer recall of stories presented to the left ear than to the right ear (monaural asymmetry) than do normal control Ss. These studies are plagued by potential methodological problems, including differences in overall accuracy, which artifactually affect the difference scores, and scoring methods that are vulnerable to systematic bias. In this study, scores of schizophrenic, bipolar, and normal control Ss on the Auditory Comprehension Test were compared. Scoring bias was avoided by the use of blind scoring and a revised scoring manual, and artifactual effects of accuracy were considered in interpreting the results. Contrary to previous findings, the groups did not differ on either monaural asymmetry or binaural deficit.

Adult↗
PubMed1990

Facilitation of word recognition by semantic priming in schizophrenia.

Schizophrenic (n = 21), bipolar (n = 18), and normal control subjects (n = 21) were compared on a word recognition measure of semantic priming. The task involved the presentation of related, neutral, and unrelated word pairs; the second word (target word) in each pair was presented in a degraded form. Facilitation was defined as the accuracy of target word recognition for the related word pairs minus accuracy for the neutral word pairs. Titration, achieved by manipulating the degradation of the target word, was used to maintain each subject's overall accuracy for related and neutral items at approximately 50%. This procedure minimized the artifactual effects of overall accuracy on the difference score. Schizophrenics exceeded both normal control subjects and bipolar subjects on facilitation. Bipolar subjects did not differ from control subjects. The results support Maher's hypothesis that semantic priming effects are heightened in schizophrenia.

Attention↗
PubMed1990

Schizophrenic deficit in span of apprehension.

We investigated two hypotheses about the span of apprehension task in schizophrenia: (a) schizophrenics show performance deficit on the forced-choice (FC) version but not on the full-report (FR) version, and (b) schizophrenic impairment on the FC version is greater when the display subtends a wide visual angle than when it subtends a narrow one. Schizophrenic (n = 21) and normal (n = 22) groups were tested on 3 versions of the task. A narrow-angle FC version was matched psychometrically with a wide-angle one by use of a greater number of noise letters in the narrow version. Schizophrenics reported fewer correct letters than normals on the FR version but did not differ on either the wide or the narrow FC versions. The results imply that schizophrenic deficit is not specific to the FC version and that on the FC version, visual angle is not more important than number of noise letters for demonstrating schizophrenic deficit.

Adult↗
PubMed1990

Asymmetrical brain electrical activity discriminates between psychometrically-matched verbal and spatial cognitive tasks.

This study compared the asymmetry of different features of brain electrical activity during the performance of a verbal task (word finding) and a spatial task (dot localization) that had been carefully matched on psychometric properties and accompanying motor activity. Nineteen right-handed subjects were tested. EEG was recorded from F3, F4, C3, C4, P3, and P4, referred to both CZ and computer-derived averaged-ears references, and Fourier transformed. Power in the delta, theta, alpha, and beta bands was computed. There were significant Task X Hemisphere effects in all bands for CZ-referenced data and for the alpha and beta bands for ears-referenced data. The effects were always either greater power suppression in the hemisphere putatively most engaged in task processing or greater power in the opposite hemisphere. Correlations between EEG and task performance indicated that CZ-referenced parietal alpha asymmetry accounted for the most variance in verbal task performance. Power within individual hemispheres or across hemispheres was unrelated to task performance. The findings indicate robust differences in asymmetrical brain physiology that are produced by well-matched verbal and spatial cognitive tasks.

Adult↗
PubMed1990

The treatment of mixed affective disorders in general practice: a comparison of trazodone and dothiepin.

The efficacy and tolerance of trazodone in the treatment of mixed affective disorder was compared with that of dothiepin in a double-blind, parallel group study in 228 general practice patients at 10 centres. After satisfying entry criteria, patients were randomized to receive either 150 mg trazodone at night, or 75 mg dothiepin at night for a 6-week period. Efficacy was assessed using the Hamilton Rating Scales for Depression and Anxiety. Significant improvements were observed in the condition of patients in each of the two treatment groups during the 6-week treatment period (p = 0.0001), with no statistically significant difference between the groups. There were no marked differences between the two treatment groups in the type of side-effects reported in response to open questioning, although a higher percentage of symptoms in the trazodone group were mild compared to the dothiepin group, and a lower percentage were severe. The incidence side-effects recorded by means of a checklist of common psychotropic side-effects was similar for the two treatment groups: dry mouth and drowsiness were the most frequent. A slightly higher proportion of patients withdrew from the dothiepin group, and of those who withdrew a higher percentage was due to side-effects than in the trazodone group.

Adult↗
PubMed1989

Strategies for resolving the heterogeneity of schizophrenics and their relatives using cognitive measures.

The resolution of the heterogeneity of schizophrenics and their relatives using cognitive tasks requires measures of individual differences--usually of differential ability, which is inferred from differential performance. Tasks that are suited for establishing a group's differential ability are often unsuited for measuring individual differences. The problem is that for any group for which Tasks A and B have different mean accuracy, the (A - B) difference scores of individual subjects have an artifactual curvilinear relation to (A + B) overall accuracy, with the largest (A - B) scores occurring at about 50% (A + B) overall accuracy for a dichotomously scored free-response task. Two possible solutions are (a) to convert Task B scores to residualized scores, using the regression of Task B scores on Task A scores as determined for normal subjects; or (b) to titrate overall (A + B) accuracy of each subject to a constant level by manipulating a variable.

Cognition↗
PubMed1987

The measurement of foot preference.

Foot preference has been given only superficial attention in studies of hemispheric lateralization, although it has potential utility for predicting hemispheric dominance. This paper reports the development of a reliable (alpha = 0.89) 11-item behavioral inventory of foot preference. Since footedness and handedness are only partially related, both must be measured reliably to identify individuals who have a consistent right or left side preference. It has yet to be determined whether footedness or handedness has the stronger relationship to other aspects of cerebral lateralization and whether both measures together predict lateralization better than one of them alone.

Brain↗
PubMed1987

Significance of urinary extravasation during renal colic.

To establish the clinical significance of renal colic associated with extravasation of contrast material, the authors reviewed 158 consecutive patients who presented with renal colic-like symptoms at the William Beaumont Hospital Emergency Center over a four-month period. Forty-three patients were eliminated either because excretory urography was not performed or IVU did not show obstruction. Of the remaining 115 patients with "obstructive" IVUs, 21 (18 men, 3 women) or 18.3 per cent, were associated with contrast media extravasation of varying degrees. Patients with extravasation were compared with patients without extravasation by cross matching as to age, gender, and time of presentation. Extravasation patients demonstrated significantly less hydronephrosis, had smaller stones (1-5 mm) usually located at the ureterovesical junction, tended to pass their stones spontaneously, and required less hospitalization and one-third the number of manipulative procedures. There was no incidence of sepsis. The significance and future research implications of these findings are presented.

Adult↗
PubMed1987

Comparison of testosterone and LH values in subcapsular vs total orchiectomy patients.

Pre- and postoperative luteinizing hormone (LH) and testosterone values were measured by radioimmunoassay in two groups of patients undergoing subcapsular versus total orchiectomy. Average values postoperatively for testosterone for subcapsular vs total orchiectomy patients were 26.4 and 23.4 ng/100 cc, respectively. Average values postoperatively for LH for subcapsular vs total orchiectomy patients were 88.2 and 88.3 mIU/cc, respectively. There was no statistical difference between these values. Subcapsular orchiectomy remains a treatment option for metastatic prostate cancer.

Humans↗
PubMed1987

The measurement of handedness.

A handedness scale consisting of 13 questionnaire items selected from those of D. Raczkowski, J. W. Kalat, and R. Nebes (1974, Neuropsychologia, 12, 43-47) was found to have high internal consistency for both males and females (coefficient alpha = .96 for both sexes), high test-retest reliability (r = .97 for males and .96 for females), and a correlation of .83 with a behavioral measure of handedness. Males exhibited more nonfamilial, but not familial, left-handedness than did females. Self-description as strongly right-handed or as strongly left-handed predicted questionnaire handedness categorization better than did hand used for writing.

Adult↗
PubMed1987

The search for symptoms predictive of schizophrenia.

Of several scales developed in our laboratory for identifying psychosis-prone young adults, the most promising appears to be the Perceptual Aberration-Magical Ideation Scale. High-scoring subjects (2 SD greater than the mean) report many psychotic-like and isolated psychotic symptoms. Subjects were seen for a followup interview 25 months after the initial identification and interview. Three of 162 high-scoring perceptual aberration-magical ideation subjects reported having received their first clinical attention for psychosis during the followup period. Additional measures are being used in attempts to eliminate the false positives as well as to distinguish persons prone to schizophrenia from those prone to affective disorder with psychosis.

Adolescent↗
PubMed1987

Cognitive slippage and depression in hypothetically psychosis-prone college students.

Subjects who scored deviantly high on the combined Perceptual Aberration-Magical Ideation (Per-Mag) Scale and subjects who scored low on the scale were compared on two putative measures of cognitive slippage--a continued word association task and a task of referential communication. The Per-Mag subjects performed more deviantly than did the control subjects on both tasks, but those Per-Mag subjects who also scored above the mean on the General Behavior Inventory (GBI) depression subscale were most deviant. The Per-Mag Scale and the GBI are recommended for concurrent use in mass screening to identify a group of individuals who exhibit signs of cognitive slippage and who may, therefore, be at risk for the development of severe psychopathology.

Depressive Disorder↗