Remembering pictures: pleasure and arousal in memory.

Incidental memory performance for pictures that varied along the affective dimensions of pleasantness and arousal was assessed. For both an immediate and delayed (1 year later) free-recall task, only the arousal dimension had a stable effect on memory performance: Pictures rated as highly arousing were remembered better than low-arousal stimuli. This effect was corroborated in a speeded recognition test, in which high-arousal materials encoded earlier in the experiment produced faster reaction times than their low-arousal counterparts. Pleasantness affected reaction time decisions only for pictures not encoded earlier. These results suggest that whereas both the dimensions of pleasantness and arousal are processed at initial encoding, long-term memory performance is mainly affected by arousal.     

Suggestiveness in photospread line-ups: Similarity induces distinctiveness

The present research examined whether line-ups based on target (‘suspect’) face similarity are biased or suggestive. Four experiments are described in which subjects constructed photographic line-ups by selecting foils similar in appearance to a target. Later, another group of subjects who had not seen the faces before (mock witnesses) were asked to pick out the targets from the line-ups. All four experiments showed that mock witnesses selected the target significantly more often than expected by chance, thereby demonstrating suggestiveness. Three alternative line-up construction methods were also evaluated. In these methods, foil selection was based not only on target similarity but also on similarity with one or more of the other line-up faces. Results showed that alternative line-up targets were not selected significantly more often than chance, suggesting that bias was reduced. An overall analysis showed that the alternative line-ups were significantly less suggestive than target-based line-ups. The results indicate that foil selection procedures that incorporate foil-to-foil similarity produce fairer line-ups than those exclusively based on target similarity.     

Picture Perception Lab: A program for picture perception experiments on the Macintosh II

Picture Perception Lab (PPL) is a program for picture perception experiments. PPL capitalizes on the sophisticated drawing software available for the Macintosh computer by allowing the user to create stimulus images by using almost any drawing package. Through a series of user-friendly dialog boxes, PPL enables even nonprogrammers to develop, quickly and easily, tachistoscopelike vision experiments. The program allows a wide variety of experimental designs. Image exposure durations and subjects’ reaction times are precisely monitored with millisecond timing functions. Each image is drawn on the screen in a single 60-Hz refresh.     

The differentiation of rhythmic structure

Listeners judged whether two five-tone nonmetric rhythms were the same or different. Each rhythm was presented one, two, or four times to study the process of perceptual differentiation. The results indicated that the listeners perceived these rhythms in-terms.of the grouping of the tones, and not in terms of the timing between the groups. Two rhythms that had the same perceptual grouping were judged as being identical, even if the timing between the groups was different. The perception of the groupings of tones developed gradually. If each rhythm was presented only once, then the listeners had only a global percept, focused on groups (runs) of three elements, and often judged two different rhythms as being identical. If the rhythms were presented two or four times, then the grouping of the tones became more differentiated and the listeners were less likely to judge different patterns as being identical. Thus, perception of auditory rhythmic structure appears to follow the same developmental process as the perception of visual spatial structure.     

The negative generation effect: Delineation of a phenomenon

In four experiments employing between-list designs, generation was found to have negative effects on free recall of word pairs and on cued recall of the second word. In addition, generation had negative effects on measures of word-pair integration and on clustering in recall. In contrast, positive effects of generation were found on free recall of second words alone, and on a recognition test for memory of the second word. It was concluded that in between-list designs, generation led to greater individual-item processing of the generated term than reading, but this processing occurred at the expense of processing the relation between the words in a pair and processing the relations between different pairs in a list.     

Children’s competitive behavior: A challenging alternative

The effect of challenge on the cooperative and competitive behavior of 120 urban American children was assessed using two experimental game apparatuses, one of which provided a challenging cooperative response. Significantly more cooperation was observed when the subjects were presented with a challenging cooperative response. In addition, a reliable age effect was found indicating that the older subject group (10–12 years old) was more cooperative than the younger two age groups (5–7 and 8–10 years old). Finally, a significant game condition x order interaction was discovered suggesting that under some conditions the order in which the games were played affected the degree of subject cooperation. Results are related to a theory of competence motivation. It is argued that cooperation among American children may be increased if the task involves the presence of challenge. A portion of this research was presented at the biennial meetings of the Society for Research in Child Development, Detroit, Michigan, 1983.     

Understanding Seat-Belt Intentions and Behavior: A Decision-Making Approach1

In an experimental study designed to investigate a decision-making model of seat-belt use, 227 employees of an agrochemical company participated in a health information program in which they watched either a videotape on seat belts or a control videotape and completed questionnaires immediately afterward and at 3 months and 1 year after exposure. In terms of total effects, the seat-belt videotape influenced beliefs, fear, and intentions assessed immediately after exposure, but had no effect on self-reported frequency of belt use at 3 months or 1 year. A full path analysis indicated some support for the decision-making model. In particular, probability difference (the perceived reduction in risk of death or serious injury due to wearing a belt) had a large influence on intentions to wear a belt and partly mediated the effect of the videotape on intentions. Reported frequency of belt use at 3 months was influenced both by post-test intentions and by initial frequency of belt use. Similarly, belt use at 1 year was affected by belt use at 3 months and by initial belt use. The findings are discussed in terms of the role of subjective probabilities and habitual factors in seat-belt use.