Prepulse inhibition of the startle eyeblink as an indicator of temporal summation

The inhibition of the human startle eyeblink response was assessed in three experiments in which the duration of the prepulse was manipulated. In all cases, inhibition of startle was more pronounced as prepulse duration increased from 6 to 50 msec. Inhibition of startle amplitude for single prepulses was not significantly different from that for paired prepulses (Experiment 1), but inhibition was more pronounced as prepulse intensity increased (Experiment 3). Varying the interval between prepulse offset and startle-stimulus onset had no significant effect on inhibition (Experiment 2). These data demonstrate the sensitivity of startle inhibition to prepulse duration, and suggest that this response system can be used to evaluate early temporal summation in the auditory system.     

A behavioral link between the oculomotor and cardiovascular systems

Although the eyes and the heart serve very different purposes, each receives autonomic innervation. Capitalizing on recent theoretical and technological innovations in the understanding and assessment of oculomotor and cardiovascular behavior, three experiments measured behavioral covariation between the oculomotor and cardiovascular systems. Measures of dark focus and dark vergence indexed oculomotor tone, and the spectral decomposition of variations in heart rate indexed cardiovascular control mechanisms. In Experiment 1, individual differences in cardiovascular parameters could predict individuals’ dark vergence (R²=.806) but not their dark focus (R²=.404). In Experiment 2, the same parameters were measured from subjects who experience either panic attacks (n=11) or blood phobia (n=9). Heart rate was positively correlated with dark vergence and the two subject groups were separable based on both oculomotor and cardiovascular variables. Using a within-subjects approach, Experiment 3 found that both dark vergence and dark focus tended to be nearer during sympathetic dominance of the heart than during parasympathetic dominance, within-subjects variations in cardiovascular parameters could predict dark focus, and between-subjects variations in interbeat intervals could predict dark vergence. Shared patterns of autonomic activation may be responsible for this eye-heart link.     

Shape discriminations of three-dimensional objects depend on the number and location of bends

In three experiments, subjects made shape discriminations of three-dimensional objects differing in orientation, number of bends, and location of bends (e.g., the central arm vs. a minor subarm). In general, encoding times at 0° disparity on bothsame anddifferent trials were affected by the number of bends, but only after a certain threshold of bends in the objects had been reached (Experiment 1). This effect was not due to the subjects’ having to search for matching ends of the objects (Experiment 2). In contrast, rotation rates were influenced by the location of the bends, but not by the number of bends per se (Experiment 3). The results support a representational scheme that is hierarchical, but not necessarily one in which the principal axis of an object is paramount.     

Adapting Basic Skills to Counsel Children

The purpose of this article is to help counselors modify basic adult interviewing skills, often the focus of the skill development component in counselor education programs, for more effective application with elementary-age children. In particular, 4 specific areas regarding counseling skills are presented: (a) establishing the appropriate physical environment, (b) building trust, (c) maintaining the counselor's facilitative attitude, and (d) using questions appropriately. Recommendations on how these skills can be modified are also discussed.     

Rationally developed fake-good and fake-bad scales for the Jesness Inventory

Develops two validity scales for the Jesness Inventory using a rational approach: a fake-good scale, Lie (L); and a fake-bad scale, Overt Symptomatology (OS). Effectiveness was assessed using 293 male delinquents classified as fake-good, fake-bad, or honest based on a matched-pair MMPI-A. L was moderately effective in detecting the fake-good set, and OS tentatively effective in detecting the fake-bad set. Both correlated well with their MMPI-A counterparts. Sensitivity, specificity, positive predictive power, negative predictive power, and overall effectiveness data were reported. The L scale and OS scale were related to race but differences were less than 1 raw score point. L was unrelated to age. OS was related to age, with younger children showing more willingness to admit to symptomatology. Age-based modified T-score norms were developed for the newly constructed scales using 1142 male and 360 female delinquents. ages 13–18.     

Remembering the levels of information in words

The qualitative nature of the incidental memory trace produced by perceptual and conceptual processing within a speeded inference task was examined. Performance on recall and auditory recognition tests replicated the general finding that semantic processing leads to better retention of words than does nonsemantic processing. This pattern of results was reversed on a visual recognition test designed to measure the amount of perceptual information remembered. These data suggest that different types of processing result in different aspects of the stimulus being encoded, with conceptual processing resulting primarily in the encoding of semantic information and perceptual processing resulting primarily in the encoding of physical information. Thus, the effectiveness of a particular kind of processing for good memory performance depends on the kind of information being tested.     

THE FUNCTIONAL RELATIONSHIP BETWEEN ARTIFICIAL FOOD COLORS AND HYPERACTIVITY

The presence of a functional relationship between the ingestion of artificial food colors and an increase in the frequency and/or duration of selected behaviors that are representative of the hyperactive behavior syndrome was experimentally investigated. Two eight-year-old females, who had been on the Feingold K-P diet for a minimum of 11 months, were the subjects studied. The experimental design was a variation of the BAB design, with double-blind conditions. This design allowed an experimental analysis of the placebo phases as well as challenge phases. Data were obtained by trained observers on Out of Seat, On Task, and Physically Aggressive behaviors, as they occurred in the subjects' regular class setting. Results indicated (a) the existence of a functional relationship between the ingestion of artificial food colors and an increase in both the duration and frequency of hyperactive children.