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.     

Facing up to the issues: Reply to Hellige (1983)

In a recent article in this journal, Hellige (Brain and Cognition, 2, 199-203, 1983) presented a critique of the chimeric-face technique that was used by us to validate a hand preference questionnaire. Data were presented by Hellige to show that the left visual field (LVF) bias that occurs on this task is due primarily to differences in detail in the features of the two faces and not because of right hemisphere dominance for face perception. In our rebuttal, we acknowledge that the two faces are not mirror-image duplicates of each other, but contend that this fact does not explain why differences between left-handers and right-handers have been observed on this task. Further data on the role of handedness as well as other variables impacting on this task are presented. A possible explanation is also offered for the rather small extent of LVF bias that Hellige obtained when he used corrected (i.e., true mirror-image) versions of Jaynes' chimeric faces.     

Knowledge of the world of work: A test of occupational information for young men

The study evaluates a test of occupational information administered to a national sample of 5000 young men, aged 14–24 in 1966, as part of the National Longitudinal Surveys of employment behavior. The predictive validity of the test score is assessed by reference to multiple regression analyses which confirm the significance of the score as an independent predictor of subsequent hourly earnings and occupational status. Correlation and factor analyses are used to examine the quality of the measurement instrument. All in all, the instrument is judged to exhibit desirable characteristics in terms of internal consistency reliability, discriminatory power, and level of difficulty. The test's reliability compares favorably with a commercially produced test designed to be used in counseling as a measure of occupational knowledge. With the possible modification of deleting a section relating to knowledge of earnings differentials, the test is commended to those involved in assessing and counseling the occupational choice process.     

Predictive value and psychological meaning of vocational aspirations

The psychological meaning and predictive value of a person's vocational aspirations were examined by applying Holland's typology to the vocational aspirations of high school juniors (N = 1005), college juniors (N = 692), employed adults (N = 140), and a second sample of college students studied over a one-year interval (N = 624). The aspirational data were obtained from the Daydreams section of the Self-Directed Search (Holland, 1972). Categorical and correlational analyses show that a person's retrospective vocational aspirations have coherence and yield efficient predictions of subsequently expressed choice. In addition, the degree of coherence or similarity among a person's vocational aspirations provides a potentially useful index of a person's decision-making ability.     

The effect of children's spontaneous cognitive sets on discrimination learning

Two experiments investigated the role of children's spontaneous cognitive “sets” in pictorial discrimination learning. Lists were constructed to highlight either perceptual or conceptual similarities among the stimuli. In each experiment age by treatment interactions revealed that in comparison to the behavior of older children (sixth graders), that of younger children (kindergartners) is governed more by the perceptible than by the conceptual attributes of stimuli—data in complete accord with Bruner's view of cognitive development.     

Choice times and Spence's discrimination learning theory

In two experiments, rats acquired brightness discriminations in a free-operant circular runway with two response alternatives. Both individual and group choice times revealed continuous changes that were not apparent in the discrete measure of choice. Two major assumptions of Spence's discrimination learning theory were confirmed: (a) learning is continuous, and (b) discriminative stimuli in simple discrimination tasks of both simultaneous and successive types are compounds with position elements as well as elements from the relevant visual dimension. The distinctive, consistent pattern of learning revealed by the choice-time measure suggests that position habits reflect a learning strategy in which the complex task is learned as a series of simpler ones.