Luminous targets: Visibility fluctuations modified by similar verbal responses

Ss reported visibility fluctuations in a luminous target consisting of small, medium, and large circles. Each S had previously learned a response to each of the three circles. The experimental group learned two words which were free associates of each other and a third unrelated word. The control group learned three unrelated words. Concurrent visibility for the pair of circles associated with related words was greater than for the pairs associated with unrelated words. Thus word associations influence perception of stimuli for which the words are responses.     

Perceived common rotary motion of ambiguous stimuli as a criterion of perceptual grouping

Apparent common behavior of contours with respect to a property for which each contour is ambiguous (in this case direction of rotary motion in depth) was used as a criterion of the unitary processing of the contours or “grouping.” Grouping was found to decrease as a monotonic function of the difference in line orientation and, for fixed orientations, to decrease as a monotonic function of line separation. These results are tentatively attributed to the distribution of line detectors in the projection area.     

On the division of attention: A disproof of the single channel hypothesis

In dichotic listening, subjects are apparently unable to attend simultaneously to two concurrent, auditory speech messages. However, in two experiments reported here, it is shown that people can attend to and repeat back continuous speech at the same time as taking in complex, unrelated visual scenes, or even while sight-reading piano music. In both cases performance with divided attention was very good, and in the case of sight-reading was as good as with undivided attention. There was little or no effect of the dual task on the accuracy of speech shadowing. These results are incompatible with the hypothesis that human attention is limited by the capacity of a general-purpose central processor in the nervous system. An alternative, “multi-channel”, hypothesis is outlined.     

Reacting to reactance: An Interpersonal interpretation of the need for freedom

This study was designed to investigate the conditions under which the negative consequences of social influence attempts can be mitigated by freedom-affirming interventions. Eighty-eight high school girls received an influence message, presumably written by a co-worker, containing either a threat or a promise. In addition, subjects were or were not given a choice option as to mode of compliance, if they chose to comply with the message. In half the cases, the Interpersonal condition, subjects received their choice/no choice option from their co-worker; in the other half of the cases, the Noninterpersonal condition, subjects were assigned the choice/no choice option by a random event unknown to the influencing agent. As anticipated, in the Interpersonal as compared to the Noninterpersonal condition, (a) threats produced greater compliance when a choice was offered than when it was not, and (b) promises and threats were more equivalent in gaining compliance when a choice was offered than when it was not. These results, which suggest that in a social setting individuals' concerns about freedom are interpersonally motivated, are discussed in terms of their relation to and implications for reactance theory.     

Social facilitation in chickens: A different level of analysis

An assumption of the arousal (D × H) model of social facilitation effects is that in an otherwise constant stimulus situation the simple presence or absence of a conspecific has a quantitative influence on the D component, and that the habit hierarchy in the situation (H) is unaffected. However, certain evidence from avian subjects seemed inconsistent with the multiplicative effects predicted by the model, and experiments were conducted with the aim of resolving this discrepancy. In general, chickens were tested for consummatory responses in the company of companions, in isolation, or in the company of strangers. Clear findings emerged from these tests that showed that only the companion conditions were “facilitative”. Under the other test conditions there were qualitative (as opposed to merely quantitative) shifts in responses. Apparently, the different social test conditions evoked qualitatively different response hierarchies, and “facilitation” reflected this sort of shift rather than simple quantitative changes in arousal (D) across conditions. It was argued, therefore, that the appropriate level of analysis for facilitation effects for animals in a free response situation is not within the (D × H) envelope, but rather at the level of S (stimulus situation) in the S → (D × H) → R formulation. Implications for the analysis of social facilitation effects in humans were discussed.     

The Tyranny of Numbers: Does Group Size Affect Petition Signing?

Conformity research proposes that an individual's tendency to conform increases linearly as a function of group size, reaches an early plateau, and remains stable thereafter, An experiment was performed to test the generality of this notion to a common group pressure situation: petition-signing. Results revealed no meaningful relationships whatever between the percent of subjects who signed and the number of previous signatures (0 through 8), the forcefulness of the solicitor's approach, and subject's sex. A female petitioner did receive more signatures than a male, however. Results were interpreted as supporting the validity of petitions as indicators of public sentiment.     

The anomaly of anomaly

In order to determine whether mechanically generated sentences, often referred to in the literature as anomalous, are in fact anomalous, subjects in the present experiment were asked to do two different tasks: a paired-associates learning task involving anomalous sentences as responses, and a second task in which they were asked to interpret such sentences. These tasks were counterbalanced across different groups of subjects. Results of the interpretation task showed that a large proportion of subjects were able to give interpretations for anomalous sentences, while learning results indicated that anomalous sentences were more difficult to anticipate than natural sentencesonly when task order was Learn first, Interpret second. In the order Interpret-Learn, differences in ease of learning between anomalous and naturally occurring sentences did not appear. The results of this study demonstrate that anomalous sentences are interpretable, that a range of difficulty for such sentences can be established, that anomalous sentences are learned as easily as naturally occurring ones after interpretation, and that many of the interpretations given to such sentences are metaphoric in character. These findings are discussed in terms of their implications for models of lexical organization.     

Differentiating psychiatrically disturbed children on the basis of a structured interview

A structured psychiatric interview designed for both clinical assessment and data collection was given to 50 pairs of well-matched pediatrie and psychiatric clinic children and their mothers. The two groups were shown to be dearly distinguished on the basis of numbers of symptoms. Behavior and school symptoms gave the sharpest distinction between the two groups. Neurotic and somatic symptoms were the poorest discriminators. The psychiatric children showed significantly more antisocial symptoms than their matched pediatrie peers. Age differences showed the expected trends with the widest divergence in the number of symptoms being in the oldest age group.This study was supported in part by NIMH Grant 05938.     

Orientation of stimuli and binocular disparity coding

An experiment is described which attempts to relate physiological work on disparity coding in the cat to a psychophysical situation using human subjects and Julesz stereograms composed of small line elements. It was found that depth perception occurred only if matching disparate lines in each stereogram shared a similar orientation. Depth began to deteriorate if an orientation difference exceeded 10° and it was extinguished at about 60°. The results are interpreted as supporting the hypothesis that shape-sensitive disparity detectors of the kind found in the cat exist also in man.