Wisconsin Card Sorting in adolescents: analysis of performance, response times and heart rate

Forty-nine adolescents performed the Wisconsin Card Sorting Test (WCST). A main PCA component of WCST performance was identified as 'efficiency of reasoning'. This factor was related to feedback processing. From the WCST, a perseveration score can be derived. Perseveration is the continued application of a rule, after it has been disconfirmed. We compared more and less perseverating subjects in relation to stimulus-response (SR) time, feedback inspection time and cardiac acceleration and deceleration. Less perseverating subjects responded faster, and had longer and more adaptive inspection times of error feedback. We examined the switch from rule application to rule search, and the difference between correct and error responses. A transient cardiac deceleration at the initiation of rule search was interpreted as a change in supervisory attention. An error-related deceleration to negative feedback was interpreted as a disturbance of higher control processing. Previous trial feedback influenced current processing time, feedback inspection time, and the cardiac acceleration and deceleration responses.     

Psychological confounds in medical research: the example of excessive cough in asthma

This experiment tested the hypothesis that the setting in which research is conducted may dominate symptom magnitude. Cough was induced with inhaled citric acid and its magnitude was influenced by changing the setting in 30 adolescents with asthma. Cough thresholds for citric acid were determined. The participants were assigned to a condition emphasising asthma, or a control condition, described as estimation of lemon flavors. All participants inhaled (in different order) thresholds for citric acid, 50% of these thresholds, or placebo. Results showed that both cough frequency and subjective 'cough tendency' were significantly higher in the asthma condition. State anxiety was higher in the asthma condition, but correlated only moderately with cough. Lung function, severity of asthma, trait anxiety, age or sex did not correlate with cough. It was concluded that patients with asthma cough more often in a situation which they have learned to associate with asthma.     

Facial composite production: a comparison of mechanical and computer-driven systems

Computer-driven systems for constructing composite faces of suspects (E-fit; Mac-a-Mug) have largely replaced mechanical systems (Photofit; the Identikit) in police use, yet little is known of their comparative effectiveness in rendering an accurate likeness. Participants (N = 24) constructed 2 of 4 familiar or unfamiliar faces, for one of which they used Photofit and for the other, E-fit. A likeness of each face was made first under target-absent conditions and then with photographs of the target present. The accuracy of the resulting composites was assessed by familiarity ratings, names elicited, and matching accuracy. The computer-driven system showed consistent superiority only when a familiar face was constructed in the presence of photographs; when participants worked from memory, E-fit was no better than Photofit. The implications of these findings for theories of face retrieval and the operational use of composites are discussed.     

Contents of Volume 14

Volume Contents

Contents of Volume 14