Intelligence, Callous-Unemotional Traits, and Antisocial Behavior

Research has consistently shown that children with severe conduct problems often exhibit intellectual deficits, especially in their verbal abilities. We investigated whether or not this finding only applies to certain subgroups of children with severe conduct problems. In a sample of 117 clinic-referred children between the ages of 6 and 13, we assessed for Oppositional Defiant Disorder (ODD) and Conduct Disorder (CD) symptoms using a structured diagnostic interview with each child's parent and teacher, callous and unemotional traits using parent and teacher ratings, and intellectual functioning using a standard individually administered intelligence test. Children with an ODD or CD diagnosis who did not show callous and unemotional traits showed a deficit on subtests measuring verbal reasoning ability relative to a clinic control group. Children with an ODD or CD diagnosis who also showed callous and unemotional traits did not show a verbal deficit and, in fact, showed a trend toward having weaker nonverbal abilities. These results highlight the importance of recognizing distinct subgroups of children with severe conduct problems when studying potential intellectual deficits in these children.     

Listener: A tool for client-side investigation of hypermedia navigation behavior

Behavioral researchers have employed hypermedia-based software applications in their experiments for some time. More recently, interest in the World-Wide Web has developed among researchers in the social sciences, and popular use of this new medium continues to grow at an incredible rate. This paper describes Listener, a tool developed to log users’ hypermedia and World-Wide Web navigation behavior using Apple Macintosh computers in a laboratory setting. Listener is able to capture navigation actions through cached documents, overcoming some of the problems associated with analyzing standard web server logs.     

Neuropsychological performance and suicidal behavior in adult psychiatric inpatients.

Although various studies have shown that suicidal persons exhibit greater cognitive deficiencies than both normals and other psychiatric patients, researchers as yet have been unable to account for the source(s) of the differences. Some of these differences (e.g., cognitive rigidity and impaired problem solving) hint of possible organic involvement. This study explored the relationship of neuropsychological functioning to suicidal behavior by comparing 20 suicidal and 27 nonsuicidal psychiatric inpatients on several tests of neuropsychological functioning. Although results showed no significant differences between the two groups on most measures, both groups showed evidence of notably high levels of cortical dysfunction relative to test norms. Thirty-five percent of suicidal patients and 44% of nonsuicidal patients scored in the impaired range. Implications of this high frequency of impairment for the treatment of suicidal and nonsuicidal psychiatric patients are discussed.     

Coding strategies,perceptual grouping,and the “variability effect” in free recall

Three experiments examined the effects of constant vs. varied input of letter strings on recall, and then examined the effects of such training in the learning of new lists of letter strings. Letter strings were constructed from pairs of trigrams spatially grouped, and were presented either consistently or with different spatial groupings on successive presentations. In Experiments I and II, varied input produced substantially greater recall than constant input. When transferred to a new list of letter strings, containing either the same general structure or a new scrambled structure, recall of the second list was determined primarily by conditions of first-list input, and unaffected by second-list structure. Although the "variability effect" did not appear in the training phase of Experiment III, Varied input led subjects to regroup or integrate the letter sequences more frequently and produced similar transfer effects as in Experiments I and II.