RÉSUMÉ
40 schizophrenic subjects, divided into paranoid/non-paranoid categories and 14 normal controls were presented a task which involved making "same-different" judgments during random presentations of a series of visual comparison stimuli with a standard which represented the midpoint of the stimulus continuum. Using Sternberg's Choice RT paradigm for studying the locus of cognitive deficit, difficulty at the response-selection stage was manipulated while holding other stages constant. It was predicted that paranoids would have shorter RTs at easy decision points and longer RTs at difficult decision points relative to non-paranoids. The directions of the differences were as predicted but did not attain statistical significance. Both schizophrenic groups, compared to normals, made significantly fewer "same" responses on those trials where the comparison and standard were most similar.
Sujet(s)
Prise de décision , Schizophrénie paranoïde/psychologie , Psychologie des schizophrènes , Perception des couleurs , Femelle , Humains , Mâle , Temps de réactionRÉSUMÉ
15 autistic children were matched with normals on the Beery-Buktenica Developmental Test of Visual-motor Integration. The two groups were subsequently compared on ability to (1) increase geometric figure-copying performance using additional information provided during subsequent trials, (2) make figure-ground resolutions, (3) perform a fine motor integration task, and (4) cope with background interference while responding on the Developmental Test of Visual-motor Integration. The primary deficit observed in the autistic subjects appeared to be defective monitoring of the motor response.
Sujet(s)
Trouble autistique/complications , Cognition , Aptitudes motrices , Perception visuelle , Adolescent , Attention , Enfant , Enfant d'âge préscolaire , Perception de la forme , HumainsRÉSUMÉ
To assess the relative influence of decisional ambiguity and response uncertainty on task difficulty, a pattern discrimination task was presented to 60 college undergraduates. The comparison stimuli were nine 20 X 20 matrices of randomly assigned black and white squares, with percent of black squares varying evenly from 10% to 90%. The standard contained 50% black squares. In a low-response uncertainty condition there were two response categories, and five in a high uncertainty condition. It was hypothesized that decisional ambiguity should be greatest at the boundaries between categories. The results suggested that decisional ambiguity was the critical factor determining judgment difficulty.