PROMOTING AUTOMOBILE SAFETY BELT USE BY YOUNG CHILDREN

A program using behavioral practice, assertiveness training, and social and contrived reinforcers was developed to establish and maintain automobile safety belt use by young children. Sixteen children (ages 4.8 to 7 years) who never used their safety belts during a 5-day preexperimental observation period were randomly assigned to two groups of eight each. A multiple baseline design across groups was used to evaluate the effectiveness of the training program. During the 8-day baseline period for Group 1, no children used their safety belts when unobtrusively observed while being driven from school. During the 26-day intervention period, the children were buckled up on 96% of the observations. Follow-up probes conducted 2–3 months after program discontinuance found safety belt use to range from 86% to 100%. For Group 2, the 14-day baseline safety belt use averaged 6% and increased to a mean of 81% during the 20-day training and maintenance program. Follow-up probes 2–3 months later found safety belt use to occur during 75% to 96% of the observations. Parent questionnaires indicated the generalizability and social validity of the program.     

Stimulus categorization by brain-damaged patients

Patients with localized insult to the right hemisphere, or to either the anterior or the posterior portion of the left hemisphere, as well as neurologically intact controls, evaluated stimuli on a seven-point rating scale for their degree of category membership. The stimuli were taken from one of two continua, one composed of fruit and vegetable items, and the other of items differing in hue and shape. Different subsets of stimuli provided different contexts for the judgments of category membership. The two left-hemisphere groups showed anomalies in categorizing the fruit and vegetable items but not the perceptual items, while the reverse was true for the right-hemisphere patients. Moreover, both left-hemisphere groups demonstrated context effects in their judgments of the representativeness of the fruit and vegetable items, but differed in the way in which they responded to changing contexts. Left posterior patients demonstrated weak category boundaries and even reclassified items. In contrast, patients with left anterior damage showed highly categorical responses and less differentiation of items within a category. All groups showed striking context effects in judgments of perceptual items in terms of changes in representativeness ratings and the location of a category boundary. Alternative interpretations of the results are offered.     

Menstruation and crime: A critical review of the literature from the clinical criminology perspective

The authors review the literature on the relationship between menstruation and crime, focusing upon the methodological limitations of these studies in the broader context of criminological and menstruation research. Based on this review, they conclude: the present state of scientific knowledge is such that it is unknown whether there is an association between any phases of the menstrual cycle and crime; there is no evidence linking fluctuations in reproductive hormones to criminal behavior; and, this lack of scientific knowledge is so glaring that evidence regarding menstruation and crime should not be admissible in criminal trials.     

The ABCs of categorical perception

Studies of speech perception first revealed a surprising discontinuity in the way in which stimulus values on a physical continuum are perceived. Data which demonstrate the effect in nonspeech modes have challenged the contention that categorical perception is a hallmark of the speech mode, but the psychophysical models that have been proposed have not resolved the issues raised by empirical findings. This study provides data from judgments of four sensory continua, two visual and two tactual-kinesthetic, which show that the adaptation level for a set of stimuli serves as a category boundary whether stimuli on the continuum differ by linear or logarithmic increments. For all sensory continua studied, discrimination of stimuli belonging to different perceptual categories was more accurate than discrimination of stimuli belonging to the same perceptual category. Moreover, shifts in the adaptation level produced shifts in the location of the category boundary. The concept of Adaptation-level Based Categorization (ABC) provides a unified account of judgmental processes in categorical perception without recourse to post hoc constructs such as implicit anchors or external referents.     

Analyzing runs of an event occurring in a series with other kinds of events

A method for analyzing runs of an event occurring in a series with other kinds of events is presented. The first step of the analysis is to determine whether the event of interest occurs in longer runs than would be expected by chance. For this purpose, a cumulative frequency histogram, consisting of the relative proportions of runs as a function of length, is compared with a theoretically derived frequency histogram by means of the Kolmogorov-Smirnov test. The theoretical histogram is the outcome of a Bernoulli process; it represents the distribution of run lengths that would be expected by chance for a given base-rate probability of occurrence of the event of interest. Iteratively applied Z tests are proposed as a post hoc procedure for use when the Kolmogorov-Smirnov test reveals that the histogram of runs is not comparable to the theoretical histogram. The results reveal how the two histograms differ. Performing the same analysis on the class of all other events reveals whether runs occur in proximity. When they do, the frequency histogram for the event should be recalculated, allowing for brief intervening runs of other events, and tested with the appropriate theoretical distribution.     

Postnatal development of respiratory and vocal responses during aversive classical conditioning in cats

Respiratory rate, respiration amplitude, and vocal responses were recorded in cats of different ages during classic conditioning. Vocal responses to the conditional stimulus (CS) appeared first in 8-week-old kittens, and became prominent at older ages. An increase in respiration rate occurred after the onset of the CS in cats of all ages. Similarly, the decrease of respiration amplitude was observed at all ages, but only in 8-week-old and older subjects did this response resemble an adult pattern. In 4-week-old kittens the response was characterized by an early and brief peak, suggesting an alpha conditional response (CR). Clear and significant discrimination between a warning and a safety signal was present in both respiratory and vocal responses after the age of 8 weeks.