Feature-positive effect in adults and attention to portion of stimulus array

In three experiments, adult humans were tested in a feature-positive or feature-negative simultaneous symbol task. In Experiment 1, some persons focused on the correct side of the stimulus cards, whereas other persons focused on the not-correct side of the stimulus cards. The feature-positive group learned faster than the feature-negative group did in the correct side condition; the feature-negative group learned faster than the feature-positive group did in the not-correct side condition. In Experiments 2 and 3, all persons focused on both the correct and not-correct sides of the stimulus cards. Under these circumstances, feature-positive and feature-negative performances were comparable. These results indicated that the usual superiority of feature-positive over feature-negative learning results from a tendency to attend to only a portion of the stimulus array.     

The effect of sound on visual apparent movement

Twelve subjects found the longest possible interstimulus interval (ISI) at which they perceived continuous apparent motion of one light instead of partial motion or succession between two lights. In the visual condition, two lights only were presented. In the bimodal conditions, binaurally presented tones were presented synchronously with the lights, and the lights and tones were either spatially congruent (in phase) or incongruent (180 degrees out of phase). Bimodal presentations lowered the upper ISI threshold for the perception of visual apparent motion, and the reduction was greater when the tones and lights were spatially congruent. The threshold reduction may be caused by a perceptual inference about localization of the lights in space or by a change in visual persistence.     

A preliminary report on the nature of interactions in a mental-handicap institution

A preliminary analysis of the reactions by staff and other residents to the behaviour of mentally-handicapped people living in a medium-sized institution is presented. The subjects' behaviour was categorized as appropriate, inappropriate or neutral according to culturally-normative criteria. It was found that, for the majority of time there was no reaction to the subjects' behaviour by staff or by other residents. The implications of utilizing culturally-normative criteria for categorizing behaviour are discussed. It is proposed that this type of analysis is potentially useful for understanding the nature of interactions in institutions.     

The role of marking when reward is delayed

Two-choice spatial discrimination by rats is enhanced if a salient stimulus marker occurs immediately after every choice response and again after a delay interval (Lieberman, McIntosh & Thomas, 1979). Three experiments further explore this effect. Experiment 1 found that the second marker is unnecessary. Experiment 2 found that a marker presented before a response is as effective as one presented after. Both effects could be explained in terms of markers focusing attention on subsequent cues. Experiment 3, however, found that markers after choice enhance learning even when no discriminative cues are present following the marker. Markers thus appear to initiate both a backward search through memory and attention to subsequent events; both processes help to identify events that might be related to the unexpected marking stimulus.     

Spatial metrics of integral and separable dimensions

Two experiments were conducted to investigate the relationship between dimensional integrality and the form of the combination rule or spatial metric used in a similarity judgment task. In Experiment 1, two groups of eight subjects judged the dissimilarity of all pairwise combinations of 12 rectangles differing in height and width (integral dimensions) or 12 circles differing in size and diameter orientation (separable dimensions). The dimensional organization and spatial metric of both sets of dimensions were determined. The results showed that differences in height and width contributed independently to judgments of the overall dissimilarity of rectangles and that these dimensions were combined using a Euclidean metric. In contrast, substantial interactions between circle size and diameter orientation were found. Combinations of these dimensions also appeared to violate the triangle inequality implying that no spatial metric was appropriate. In Experiment 2, parallelogram size and tilt were similarly analyzed. Although some degree of dimensional interaction was observed, it was found that on the average these dimensions were combined using a city-block metric. In a subsequent speeded classification task, orthogonal interference was observed, which suggested that size and tilt are integral dimensions. The implications of both experiments for the supposed association between the Euclidean metric and dimensional integrality are discussed.     

Selective attention to multidimensional auditory stimuli

Event-related brain potentials (ERPs) elicited by multidimensional auditory stimuli were recorded from the scalp in a selective-attention task. Subjects listened to tone pips varying orthogonally between two levels each of pitch, location, and duration and responded to longer duration target stimuli having specific values of pitch and location. The discriminability of the pitch and location attributes was varied between groups. By examining the ERPs to tones that shared pitch and/or locational cues with the designated target, we inferred interrelationships among the processing of these attributes. In all groups, stimuli that failed to match the target tone in an easily discriminable cue elicited only transitory ERP signs of selective processing. Tones sharing the "easy" but not the "hard" cue with the target elicited ERPs that indicated more extensive processing, but not as extensive as stimuli sharing both cues. In addition, reaction times and ERP latencies to the designated targets were not influenced by variations in the discriminability of pitch and location. This pattern of results is consistent with parallel, self-terminating models and holistic models of processing and contradicts models specifying either serial or exhaustive parallel processing of these dimensions. Both the parallel, self-terminating models and the holistic models provide a generalized mechanism for hierarchical stimulus selections that achieve an economy of processing, an underlying goal of classic, multiple-stage theories of selective attention.     

Children's strategies for controlling affective responses to aversive social experience

It was hypothesized that one mechanism of self-control that children develop is the strategic capacity to select the experiences they encounter. This hypothesis led to the prediction that children would deal with certain aversive social experiences by seeking out or taking advantage of opportunities for nurturant experiences. Young children were exposed to an aversive social experience in which they received less nurturance than a peer, a positive experience in which they received more nurturance, or a neutral experience in which nurturance was equal. Subsequently, an opportunity was provided for children to control the length of time they watched a highly nurturant television program. As predicted, boys experiencing an aversive social encounter increased the length of time they exposed themselves to the nurturant television show, and their level of reduced positive affect was related to how long they watched the nurturant content, further supporting the interpretation that they did so in response to their own affective state. Girls did not adopt the strategy of self-exposure to nurturant television but did appear to engage in self-distraction during the aversive social experience. Despite the apparent use of control strategies, there was no indication that these strategies were effective for the amelioration of reduced positive affect resulting from the aversive social experience. Discussion focuses on the sex differences observed in the adoption of strategic behavior and factors contributing to the ineffectiveness of the control strategies. A general model is proposed for personal and environmental factors requisite for the selection, employment, and effectiveness of strategies to control experiences and their affective consequences.     

Aerobic conditioning and stress reduction: Participation or conditioning?

The efficiency of an aerobic conditioning program (jogging) is compared to cognitive therapy (stress inoculation) and a waiting list control in modifying self-reported chronic stress. The participants were community residents; 48 were females and 25 were males. Treatment sessions were conducted over a 10-week period with subjects meeting in small groups for 1$\text{1}\text{2}$ hours per week. The State/Trait Inventories, a Tension Thermometer and a submaximal bicycle ergometer test were administered pre, post and follow-up. Repeated measures, multivariate analysis of variance indicated that both treatments were effective in reducing stress compared to the waiting list control and that these changes were maintained at 3-month follow-up. Multivariate analysis indicated that participants with higher initial levels of aerobic fitness did not report less stress, while participants who obtained higher levels of fitness during the conditioning program fared no better in reducing stress than their counterparts who obtained lower levels of aerobic fitness. These findings are of interest because they suggest that the psychosocial components of the fitness program were active ingredients of treatment rathee than the effects of improved cardiovascular functioning.     

Sexual activity and contraceptive use among low-income urban black adolescent females.

A modified form of Nathanson and Becker's (1983) Health Belief Model Questionnaire and other measures designed to assess cognitive processing were administered to low-income black adolescent female clients of an inner-city comprehensive health care clinic. The purpose of the study was to explore determinants of sexual activity and contraceptive use. Subjects were classified as not sexually active (n = 50), sexually active/noncontracepting (n = 20), or sexually active/contracepting (n = 72). Not sexually active subjects tended to be younger, more career motivated, to have a father at home, to be more influenced by family values, and to have more conservative attitudes regarding adolescent sexuality than did sexually active subjects. Sexually active/noncontracepting subjects tended to report fewer benefits and more barriers to the use of contraception. Level of cognitive processing did not differ among the three groups, but was at a lower-than-expected level for age. Finally, inconsistent contraceptive use was common to both sexually active groups.