The effect of set size on hemifield asymmetries in letter recognition

Single letters were presented tachistoscopically in the left or right hemifield to right-handed observers. Superior recognition of letters on the right was found for letters chosen from subsets containing four items, but no differences were found when any letter, or any symmetrical letter, could appear. In a second experiment, the right hemifield advantage was found under conditions requiring the subject to determine the subset only when the subset chosen was appropriate. Results were discussed in terms of the adequacy of language-based explanations of hemifield asymmetries in letter recognition.     

Irrelevant differences in the "same"--"different" task

This article examines the effects of irrelevant information on the multidimensional "same"--"different" task. Subjects were instructed to compare two geometric figures with respect to certain attributes but to ignore other attributes in making the "same"--"different" decision. The irrelevant attributes were chosen in such a way that they could not easily be ignored to see how the existence of irrelevant differences would affect the comparison process. As expected, the overall latencies were longer than is usually found in tasks with no irrelevant differences. However, the nature of the comparison process appeared unchanged. The usual finding of a "fast-same" phenomenon persisted even when irrelevant information was present. The similarity of the results in this task to results in the "same"--"different" task with no irrelevant features supports the idea that the same comparison mechanism is used whether or not irrelevant differences are present in the stimulus pairs. The results suggest a more general-purpose comparison mechanism than is usually included in models of this task. Two-process models of visual comparisons are thus ruled out entirely. A modified version of Krueger's noisy-operator theory does appear consistent with the results.     

Contextual potentiation of acquired behavior after devaluing direct context-US associations

In two experiments, water-deprived rats were exposed to tone-footshock pairings in a particular conditioning context. In Experiment 1, the training parameters were selected on the basis of parametric pilot data so as not to produce direct associations between the conditioning context and footshock. Despite independent evidence of no appreciable direct association between the conditioning context and footshock, animals tested in the conditioning context exhibited more lick suppression to the tone than other animals tested with the tone outside of the conditioning context. Thus, the conditioning context potentiated suppression to the tone in the absence of appreciable fear of the conditioning context. In Experiment 2, training parameters were used that permitted the formation of direct associations between the conditioning context and footshock; however, for half the animals, these associations to the context were then extinguished. With the tone absent, a comparison of extinguished animals tested either in the conditioning context or outside the conditioning context detected no differences in suppression, demonstrating the effectiveness of the extinction manipulation. However, other animals also subjected to extinction of direct context-footshock associations displayed greater suppression to the tone within the conditioning context than comparable animals tested outside the context. Collectively the data indicate that the superior retention-test performance seen within the training context can arise both from the commonly assumed direct associations between the training context and the unconditioned stimulus and from the potentiation by the training context of the associations between the nominal conditioned stimulus and unconditioned stimulus.     

Young children's understanding of displaced aggression

According to previous research, young children do not understand displaced aggression. The present study examines the early phases of the understanding of the causes of moderately and extremely displaced aggression. Preschool and kindergarten children (3 to 5 years of age) viewed eight videotaped episodes of displaced aggression. Their comprehension of this aggression was assessed by means of open ended questions and forced choice picture selections. By age 5 most children had some understanding of displaced aggression, but this understanding was not complete. The early understanding revealed in the present study may be due to the use of short, simple realistic videotaped episodes appropriate for the limited processing abilities of young children. Extreme displacement was not more difficult to understand than moderate displacement.     

Accommodation fatigue and dark focus: The effects of accommodation-free visual work as assessed by two psychophysical methods

Past studies of accommodation fatigue have yielded inconsistent results, partly because they have not used direct measures of accommodation, and partly because they may have been based on a misleading conception of the nature of accommodation. The dual-innervation theory of accommodation suggests that the resting position of accommodation may be neuromuscular rather than just muscular, and that it lies not at optical infinity, as assumed by older conceptions, but at some intermediate position (dark focus). Among the predictions that may be deduced from this theory is that long-term visual work not requiring active accommodation will not induce fatigue. The present study involved continuous measurements of dark focus for 10 young adults over a 3-h period, using the laser optometer with two psychophysical procedures Ibracketing and staircase. Consistent with the prediction, no changes in dark focus were found, in spite of the demanding visual task. Furthermore, it was found that both psychophysical methods yielded essentially identical results. The practical and theoretical implications of these results are discussed, and recommendations are given regarding situations in which each of the psychophysical methods is likely to be most useful.     

Social intimacy: An important moderator of stressful life events

Two studies were conducted to explore the role of social intimacy in predicting the individual's response to stress. In the first study the experimenter reinforced the experimental subjects' verbalizations during an interview on a fixed schedule for the first 3 minutes, withdrawing reinforcement for the final 4 minutes. The control group received reinforcement on a fixed schedule for the total 7 minutes. Subjects scoring low on a measure of intimacy disclosed less personal material during the withdrawal period in the experimental condition than in the control condition in contrast to high scoring subjects who maintained their level of disclosure for both parts of the interview. In the second study, previously experienced life change events were assessed. Individuals lacking a current intimacy were found to be prone to higher levels of emotional disturbance especially when many previous negative or few positive life change events had occurred.     

Perceptual deprivation,extraversion—introversion and the autokinetic phenomenon

The present study examines the relationships between perceptual-deprivation tolerance and three variables: extraversion, the autokinetic (AK) phenomenon and field-dependence. In addition, the relationship between extraversion and autokinesis (AK) was investigated. Thirty-three male subjects were subjected to 3 hr of perceptual deprivation and, in addition, their scores on each of the three independent variables were obtained. It was found, as hypothesized, that perceptual-deprivation tolerance was negatively related to extraversion and positively related to the intensity of the AK effect. Field-dependence was not related to perceptual-deprivation tolerance. The correlation between extraversion and the autokinetic effect was significant but moderate. The nature of the relationship between these two variables is discussed.     

The relationship between the probability assessor and the outcomes of an event as a determiner of subjective probability

Two experiments were conducted in which 58 subjects assessed the probability of occurrence of positive and negative events. Two types of probabilities were assessed. The first was the probability that an event would occur, influencing the assessor him/herself (SPE). The second was the probability that the same event would occur to someone else, not influencing the assessor (SNPE). Six patterns of assessments were observed. Most of the subjects assessed SPE to be higher than SNPE for positive events and SNPE to be higher than SPE for negative events. In the first experiment SNPE was assessed in regard to someone very close and similar to the assessor while in the second experiment SNPE was assessed in regard to a less-defined “else”. In the latter case the differences between SPE and SNPE were more prominent than in the first. The explanation was given in terms of motivational factors and the availability heuristic.     

The Predictors of Post-Sterilization Regret in Married Women1

We interviewed a sample of 317 married women prior to a tubal sterilization (195) or a husband's vasectomy (122) and then reinterviewed them yearly for 5 years. Using these women's responses to six questions about their feelings and desires following sterilization, we fitted a latent-variable model of post-sterilization regret to the data by means of a linear structural equation analysis. The results confirmed our view that post-sterilization regret was not a simple psychological state but rather was a complex process with different, causally linked manifestations. This process began with a renewed interest in having a baby, proceeded to the development of negative feeling about the three decisions that lead to sterilization, and concluded with a desire to reverse the surgery. This sequence was affected by the negative, post-sterilization effects of the sterilization and by the Occurrence of divorce. Next, we identified the pre-sterilization predictors of six regret variables from our model by means of a series of linear regression analyses. The major pre-sterilization predictors of the regret process included being relatively young, ambivalence about future childbearing, negative attitudes toward sterilization, dominance of the decision making by the woman's husband, and conflict with her husband during decision making. Finally, we divided the sample into quintiles on the basis of their scores on a Pre-Sterilization Predictor Scale and assessed the performance of our predictor variables as indicators of risk of regret by determining the level of negative feelings toward sterilization in each quintile. The results confirm the discriminatory power of our predictors. The overall findings indicate a number of psychological and marital issues, the exploration of which might help counselors provide anticipatory and preventative services to couples seeking sterilization.