Categorization reaction time,category structure,and category size in semantic memory using artificial categories

This study examined the effects of category structure and category size on categorization reaction time, artificial categories being used to obtain greater experimental control than is usually found in semantic memory research. Four artificial categories varying in structure (hierarchical and nonhierarchical) and size (8 or 16 instances) were introduced to 20 adolescent subjects over a 12-week period by means of stories, exercises, and discussions. Significantly longer categorization reaction times were required for instances from the hierarchical categories, but no set size effect was found. The application of clustering and multidimensional scaling procedures to subjects’ free recall data revealed that subjects had acquired the hierarchical structures but imposed their own structures on the other categories. These findings were interpreted within a spreading activation framework.     

The generalization of the effects of a cognitive-behavioral treatment program for aggressive children

A cognitive-behavioral treatment program for aggressive children was assessed using 12 outcome measures classified into five categories which reflected a continuum of generalization of treatment effects. From a summer daycamp 41 children, ages 7 through 12, were selected based on aggressive behavior displayed during the first week of camp. They were randomly assigned to either a treatment group or a nontreatment control group. Treatment consisted of four weeks of coping-skills training using behavioral rehearsal and self-instruction training. Considering all 12 measures, treatment was found effective (F=2.90, p < .01). The most meaningful results included improved interpersonal problem-solving skills and a decrease in being disciplined for fighting. No changes were found, however, in physical or verbal aggression and in peer rating of aggression. Modest support for the effectiveness of these treatment procedures was identified, although caution is needed in considering their clinical utility. Further research and application appear justified.     

A factor-analytic study of measures of Machiavellianism

Three Machiavellian (Mach) scales together with measures of authoritarian personality, the EPQ and the 16PF test were subjected to a rotated factor analysis in order to identify and locate in personality space a Mach factor or factors. One Mach factor was identified independent of the main personality factors.     

Characteristics of schizophrenics' and neurotics' relatives

A group of adult first-degree relatives of schizophrenics were compared with a control sample of neurotics' relatives on the EPQ, an earlier version of the Eysenck P scale, and on three specially-constructed scales of ‘psychoticism’ (STA, STB and S), derived from a consideration of the clinical symptomatology of schizophrenia and of the ‘borderline syndromes’. Overall differences, in a predictable direction, were confined to the EPQ P scale where schizophrenics' relatives had significantly higher scores, though further analysis suggested that this was due partly to the raised scores of males and partly to very low P-scores seen in male neurotics' relatives. Scores on the STA, measuring schizophrenic ‘symptoms’, were very low in schizophrenics' relatives, due, it was argued, to extremely defensive responding in that group. Results are also reported for two psychophysiological measures, forearm EMG and skin conductance. Here marked group differences were observed, schizophrenics' relatives having significantly higher mean EMG and significantly lower mean skin conductance. This unusual pattern of response was especially evident in a small subgroup of schizophrenics' relatives whose personality profiles tended to differ in the predictable direction, towards greater ‘psychoticism’. The psychophysiological data were highly consistent with other results from our laboratory demonstrating a ‘dissociation’ between different measures of ‘arousal’ in high-P normal subjects and in psychotic patients and it was concluded that measures based on such a conception of the biological basis of schizophrenia offer considerable promise as high-risk indicators of psychopathology.     

The contribution of music vs instructions in the Musical Mood Induction Procedure

The relative contribution of the instructions and the music to the effects of the Musical Mood Induction Procedure (MMIP) were investigated. Using an experimental procedure which minimised covert experimenter bias, subjects performed under both elation and depression mood inductions in one of four conditions: music present or absent by mood change instructions present or absent, using a crossover design. Results indicated that instructions were both necessary and sufficient to produce change on mood sensitive measures. Mood change effects were reduced by controlling for the effect of subjects who responded so as not to ‘louse-up’ the experiment. The MMIP seems to be much less musical than the name implies. Further research is needed to determine which aspects of the instructions contribute most to the changes on mood sensitive measures.     

Do Students with Different Characteristics Take Part in Psychology Experiments at Different Times of the Semester?

ABSTRACT In this study we examined 15 personality and demographic differences between psychology students who took part in experiments at different times of the semester and different times of the day. In general, few significant relations were found and those that did emerge were small in magnitude. Females and freshmen signed up for experiments earlier in the semester. Females took part in their first experiment earlier in the semester, as did students who were Protestant and who came from smaller home towns. Students low in self-consciousness also tended to begin participating earlier. Extraverts participated earlier in the day than introverts. Results generally were consistent with previous findings of differences between research volunteers and non-volunteers. However, it was concluded that because of their small magnitude and inconsistency from site to site, with a few precautions experimenters probably need not be concerned that timing effects threaten the external validity of psychological research outcomes.