A stereotaxic positioning platform for double-angle placements

A simple and inexpensive device for double-angled positioning of electrode carriers during stereotaxic surgery is described. The device consists of a base and adjustable vertical point that is used to locate the position of final stereotaxic coordinates in space. This allows reproducible placements for deep midline brain structures that require double-angle approaches. Such placements are easily obtained with this instrument on standard and even single-carrier stereotaxic instruments.     

Heart-Rate responses (HRR) to lateralized visual stimuli

Direction of changes in heart-rate responses (HRR) were investigated in three separate experiments as a measure of differential cognitive and emotional specialization of the cerebral hemispheres. Visual stimuli were presented via the visual half-field technique in all three experiments. Slides with different contents were flashed for 200 msec on each trial either to the left or right of a center LED fixation point. The LED went on 5 seconds prior to slide onset. HR changes were scored as second-by-second deviations during 10 seconds after LED onset from pre-LED base line. In the first experiment it was hypothesized that emotionally relevant stimuli initially projected to only the right hemisphere would result in more anticipatory acceleration than when the same stimulus was initially projected to the left hemisphere. A picture of a snake and of a geometric figure were repeatedly briefly flashed to the right of the LED for half of the subjects, and to the left for the other half. There were 25 trials with an intertriai interval of 25–40 seconds. Results showed significant effects of deceleration as a function of the slide stimulus in all groups on seconds 5, 6, or 7 after onset of the center LED. Furthermore, an anticipatory acceleration was observed during the first trial-block on seconds 3 and 4 in the right hemisphere groups only with no differences between the neutral and emotional stimuli. In Experiments 2 and 3, a letter-string of six letters and a complex symmetric pattern were used as stimuli. These stimuli were chosen because previous research has clearly implicated the hemispheres to be differentially specialized in their ability to process verbal and visuo-spatial stimuli. The set-up was identical to Experiment 1, with the exception that differences in response to the two types of stimuli were evaluated on a within-subjects basis. The results from Experiments 2 and 3 showed stimulus-related deceleration, peaking on seconds 5–7 in all groups and an anticipatory acceleration peaking on seconds 3 and 4 in the right hemisphere groups, with decelerations during the corresponding seconds in the left hemisphere groups. The results are discussed in relation to recent findings by Walker and Sandman (1982) about the possibility of hemispheric specialization in psychologic influences on heart rate changes in response to environmental demands.     

Preschool teachers' ratings of behavioral problems: Observational,sociometric, and social-cognitive correlates

Behar and Stringfield (1974) have suggested that the Preschool Behavior Questionnaire (PBQ) is a reliable index of young children's social competence. However, there are few extant data in which teacher ratings of children on the PBQ have been correlated with independent assessments of social competence. In this study PBQ ratings of 123 preschoolers were correlated with observations of in-class social and cognitive play behaviors, sociometric status, and social problem-solving skills. Analyses indicated that children rated highly on the PBQ's Anxious-Fearful, Hostile-Aggressive, and Hyperactive-Distractible factors (a) displayed less mature and more aggressive in-class behaviors, (b) were less popular among their peers, and (c) were more likely to suggest negative affect strategies on the social problem-solving measure. Thus, the PBQ appears to be a useful instrument for identifying children with social problems.     

Training parents of hyperactive children in child management: A comparative outcome study

Parents of 44 hyperactive children were assigned to either a behavior modification group (PAT), a communications group (PET), or a delayed-treatment control group. Parents in the treatment groups participated in 9-week training workshops. Parents and their children were assessed before and after the workshops on measures that included ratings of hyperactivity and severity of problems, a daily checklist of problem occurrence, parental attitudes, and direct observations in a laboratory situation. Both treatment methods were more effective than a no-treatment control condition in reducing hyperactivity ratings, problem severity ratings, and daily problem occurrence. Additionally, parents receiving behavior modification training rated their children as more improved than did PET parents, were more willing to recommend the program to a friend, felt the program was more applicable to them, and were less likely to drop out of the program. Nine-month follow-up assessments indicated that treatment parents continued to view their children's behavior more positively than did control group parents. Results are discussed with respect to the implications that an educational approach to teaching child management can be an effective means of reducing behavioral problems in children, that methods differing in theoretical background and actual skills taught may result in similar outcomes, and that a "psychological," as opposed to a medical, approach to the treatment of hyperactive children can have considerable merit.     

Conditioning preparation for the nictitating membrane of the pigeon

A procedure is described for restraining the pigeon while recording movement of the nictitating membrane. The preparation provides a means of studying classical conditioning that combines the rich sensory capacities of the pigeon with the control achieved in nictitating membrane conditioning of the rabbit.     

The act frequency analysis of interpersonal dispositions: Aloofness,gregariousness, dominance and submissiveness1

A series of studies explores the act frequency analysis of personal dispositions, which entails the identification of categories of prototypical acts, delineation of internal structuring within act categories (from central to peripheral), and the assessment of individuals' dispositions in terms of the relative frequency of performing prototypical acts over a period of observation. These studies were designed to replicate the research of Buss and Craik (1980) on dominance. Through nomination procedures, 100 acts were assembled for each of three dispositions: aloofness, gregariousness, and submissiveness. The internal structure of these categories was examined through judgments of the degree to which each act is a prototypical member of the category. Prototypicality judgments for each act category by three independent panels display a substantial degree of composite reliability. Multiple-act criteria based on highly prototypical acts are predicted with significantly greater success by relevant personality scales than are multiple-act criteria based on more peripheral acts within each category. This finding holds for dominance, replicating the Buss and Craik study, and for aloofness and gregariousness. The multiple-act criteria for submissiveness, however, are not well predicted by matching personality scales. This anomaly is discussed in terms of the bipolarity of behavioral domains, the selection of matching personality scales for specific act categories, and the appropriate conceptualization of submissiveness.     

Promotion and prevention choices between stability and change

Two situations involving choice between stability and change were examined: task substitution, which deals with choosing between resuming an interrupted activity and doing a substitute activity, and endowment, which deals with choosing between a possessed object and an alternative object. Regulatory focus theory (E. T. Higgins, 1997, 1998) predicts that a promotion focus will be associated with openness to change, whereas a prevention focus will be associated with a preference for stability. Five studies confirmed this prediction with both situational induction of and chronic personality differences in regulatory focus. In Studies 1 and 2, individuals in a prevention focus were more inclined than individuals in a promotion focus to resume an interrupted task rather than do a substitute task. In Studies 3-5, individuals in a prevention focus, but not individuals in a promotion focus, exhibited a reluctance to exchange currently possessed objects (i.e., endowment) or previously possessed objects.     

Letters to the Editor

Letter to the Editor

Letters to the Editor