The symmetry of visual fields in chromatic discrimination

Both classical and recent reports suggest a right-hemisphere superiority for color discrimination. Testing highly-trained normal subjects and taking care to eliminate asymmetries from the testing situation, we found no significant differences between left and right hemifields or between upper and lower hemifields. This was the case for both of the cardinal axes of color space. In addition, there was no difference according to whether the discriminanda were delivered to the same or to different hemispheres, and we note that the same number of synapses may lie between the retina and the site of comparison whether or not the stimuli are delivered to the same hemisphere.     

Generality of a strength model for three conditions of repeated recall

A Markovian model of repeated recall is presented that is based on four memory processes: (a) a presentation increment that strengthens the memory trace of a word when the word is shown to a subject, (b) a recall increment that strengthens the trace when the subject successfully recalls the word, (c) a cueing decrement that weakens the trace as contextual cues for retrieving a word change over successive trials of attempted recall, and (d) a sampling rule that translates the strength of a memory trace into a probability of recall. Mathematically, the model predicts the relative frequencies of the recall patterns that are defined by sequences of recalls and forgets for individual words over trials. According to the model, the recallability of a word depends on its state, which is a function of (a) whether the word has been recalled for the first time, and if so, then (b) how many consecutive forgets of the word immediately precede the current trial, (c) how many successful recalls of the word have accumulated, and (d) how many previous trials of attempted recall have elapsed. Paradigms that were well described by the model were (a) no reminding, in which words were presented once and then recalled repeatedly without additional presentations; (b) restricted reminding, in which words were presented before each trial of attempted recall up to their first successful recall but not thereafter; and (c) complete reminding, in which all words were presented befor each attempted recall, whether previously recalled or not. Differences in recall among these conditions were explained in terms of differences in values of the model's parameters.     

Homotopic callosal inhibition

Previous theories concerning the function of the corpus callosum have included a “topographic” column-to-column excitatory theory and a diffuse “regional” inhibitory theory. Here it is shown that a topographic inhibitory model, in conjunction with a postulate concerning surround inhibition among cortical columns, produces complementary patterns of cortical column firing which, although qualitatively different, do not imply quantitative metabolic asymmetries. The cognitive implications of such homotopic inhibition are discussed.     

Central auditory processing : IV. Ear dominance—Spatial and temporal complexity

Ear dominance for dichotically presented tones was measured in 63 right-handed subjects when the frequency difference (Δf) was small compared to the center frequency (f_c) and again when it was large. Although two-thirds of the population exhibited a left-ear dominance in both conditions, a shift toward right-ear dominance occurred when the Δf was increased. An additional study, employing the alternating tone illusion described by Deutsch, revealed the same general effect, i.e., a shift toward right-ear dominance with increasing values of Δf/f_c. The results of these experiments, coupled with a review of previously published data of other dichotic experiments, indicate that as the ratio of Δf/f_c increases, the subjective complexity of the sound image increases, and there is a progressive emergence of a “right-ear advantage” (or ear dominance). A tentative explanation relates these results to the effects of anatomical asymmetries of primary and auditory association cortex and the efferent temporal lobe enhancement mechanism described by R. Efron, P. H. Crandall, B. Koss, P. L. Divenyi, and E. W. Yund (Brain and Language, 1983, 19, 254–263.     

Central auditory processing: I. Ear dominance—A perceptual or an attentional asymmetry?

The phenomenon of ear dominance for pitch described by Efron and Yund has been attributed by them to an asymmetry of sensory origin in the binaural integration of dichotic tone pairs. An explanation of this phenomenon in terms of an attentional bias is rejected on the basis of two experiments where the possibility of such bias was excluded. These and other experiments indicate that a simple explanation of this ear dominance in terms of a hemispheric specialization in the processing of tonal stimuli also must be rejected.     

Context and companion's behavior as determinants of cooperation and competition in school-age children

Information about the social context and a companion's actions were studied as determinants of cooperation and competition in middle childhood. In Experiment 1, first-, third-, and fifth-grade children were told that they would play a board game with another same-age, same-sex child (actually a bogus companion). The experimenter's instructions established shared rewards or winner-take-all as outcome conditions. Preprogrammed responses—100% cooperative or 100% competitive—provided information about the companion's actions. Results revealed that the companion's responses alone determined cooperation and competition among the first graders. Third graders used both types of information. Fifth graders, however, demonstrated a bias to respond cooperatively whenever a cooperative cue was present. In Experiment 2, first-grade subjects were given extra rehearsal of the game strategies, a scorekeeping procedure for use during the game, or a combination of the two. Results indicated that, under these conditions, younger subjects were able to use the instructions about reward distribution as well as the companion's actions in guiding their social behavior.     

A skills training approach to the reduction of institutional offending

Offenses committed by those held in institutions can have repercussions at several levels: the individual must suffer the consequences of his or her actions; there may be a victim; and valuable staff time is spent adjudicating the outcome. A number of studies have suggested that an adjunct to behavioural training in institutions is a reduction in institutional misbehaviour—a suggestion which the present study sought to capitalize upon in a direct manner. In a borstal for young male law-breakers, referrals of individuals who received above average numbers of discipline reports in the institution were gathered. These people were then offered a place on a training course designed to attempt to modify behaviour towards authority figures, prison officers in particular. The course was carried out in two forms: a ‘Short’ Course of 4 days duration, and a ‘Long” Course spread over 8 weeks. Assessment of the effects of training was made by monitoring levels of discipline reports, and also by the administration of self-report and personality scales. Compared with No-training and Non-referred Controls, no significant changes in the frequency of receiving discipline reports was found following either mode of training. However, a number of changes on the self-report and personality measures suggested some degree of change after training. Implications for the construction of future courses with similar objectives are discussed.     

Effects of public and private deviancy on compliance with a request

A confederate requester asked subjects to write letters for an educational campaign after they had completed a battery of tests and received either deviant or nondeviant feedback. Half of the subjects were led to believe that the requester had knowledge of their test performance; the remaining half believed that the confederate did not know their test scores. Within these conditions, some subjects believed that complying with the request would involve future meetings with the requester while others were not led to anticipate any future interaction. As expected, deviants complied more than nondeviants replicating Freedman and Doob's (1968) results; however, neither the secret/known nor the future interaction variations produced effects. Contrary to the prediction that deviants are compliant because they wish to avoid mistreatment, secret deviants complied slightly more than known deviants. Compliance was discussed as instrumental in improving self-image.     

Female preferences for male physiques

A pair comparison design was used to gather information concerning female preferences for male physiques. By independently varying the size of one of four body areas (the arms, upper trunk, lower trunk, or legs), 19 male silhouettes were constructed. Thurstone scale values indicating relative preferences among these silhouettes were generated for each of 64 female subjects. Correlations were calculated between subject variables, e.g., own physical appearance, personal habits, male and female sex-role attitudes, etc., and the underlying preference factors for male physiques. While the bulk of the significant correlations were low, accounting for approximately 5–10% of the variance, the general trend of the results suggest that women's preferences for male physiques can be summarized in terms of feminine and masculine sex-role stereotypes. Women who are traditionally feminine show a preference for traditionally masculine physiques, i.e., tapering V physiques, while less traditional women express more nonstereotyped preferences. It is also suggested that a female's preferences for male physiques may serve as an initial delimiter in narrowing the field of eligibles in heterosexual pairing.     

Spatial representation by blind and sighted children

Spatial representation by 72 blind and blindfolded sighted children between the ages of 6 and 11 was tested in two experiments by mental rotation of a raised line under conditions of clockwise varied directions.Experiment 1 showed that the two groups were well matched on tactual recognition and scored equally badly on matching displays to their own mentally rotated position.Experiment 2 found the sighted superior in recall tests. There was a highly significant interaction between sighted status and degree of rotation. Degree of rotation affected only the blind. Their scores were significantly lower for rotating to oblique and to the far orthogonal directions than to near orthogonal test positions. On near orthogonals the blind did not differ from the sighted.Age was a main effect, but it did not interact with any other variable. Older blind children whose visual experience dated from before the age of 6 were superior to congenitally blind subjects, but not differentially more so on oblique directions.The results were discussed in relation to hypotheses about the nature of spatial representation and strategies by children whose prior experience derived from vision or from touch and movement.