Wepman test of auditory discrimination: What does it discriminate

This study investigated auditory discrimination as a function of ethnic group membership within the same socioeconomic status (SES). Subjects were 126 randomly selected six-year-old students attending schools in the lower SES community of southeast San Diego. Only students with no known speech or hearing defects and of normal intelligence were included. They were assigned to one of three categories: Black, Chicano, or Anglo.Subjects were administered four tests in a counterbalanced design: the Wepman, the Gross, and the Ott. The latter two were developed for use with Black dialect and Spanish-speaking youngsters, respectively. The ANOVA results indicated a reliable difference between the main effects of the groups (F=40.34,p<.001) and tests (F=72.82, p<.001), with a significant interaction between tests and groups (F=44.91, p<.001). Interaction effects were evaluated with the Dunn theorem. Significant differences were found among Anglo, Black, and Chicano students on the discrimination list for Spanish sounds (Ott) and a significant Anglo/Black difference on the discrimination test for Black dialect (Gross). Contrary to previous findings, there were no differences between the groups on the Wepman Test of Auditory Discrimination (WTAD). However, there are significant differences between groups on separate items of this test.     

Spatial localization under conflict conditions: is there a single explanation?

Visual--auditory (VA) and visual--proprioceptive (VP) localization conflict paradigms were varied to explore the comparability of the conflict situations. In experiment 1 various attempts were made to decrease the dominance of visual information over proprioceptive and auditory target information. Pairing auditory with proprioceptive information against conflicting visual information did not lessen the visual dominance, nor did dimming the visual field. A 'cognitive' manipulation, in which the subject was led to doubt the reliability of the visual information, reduced visual dominance over audition but not visual dominance over proprioception. This difference between the two conflict situations was further explored and corroborated in experiment 2. In experiment 3 no attempt was made to lead the subject to believe that paired discrepant targets were related, and the visual dominance of audition was strong while the visual dominance of proprioception did not occur. The apparent differences between the VA and VP conflict situations are discussed with regard to the feability of generating a unitary explanation of localization conflict results. Several further factors are discussed that must be explored before undertaking such a unitary formulation.     

An illusion of auditory saltation similar to the cutaneous "rabbit"

Trains of brief clicks produced successively at 3 points in a horizontal array were not localized accurately. Observers reported clicks occurring in succession across the spaces between sources as well as at the sources themselves. The illusion is functionally related to interstimulus interval, number of clicks per speaker, and regularity of pulsing. It appears similar to Geldard and Sherrick's cutaneous "rabbit" illusion.     

The community mental health center management game: Teaching administrative skills by means of computer simulation

Clinical training in psychology rarely includes the opportunity for students to exercise managerial responsibility for a functioning human service organization. Nevertheless, many clinicians are called upon to assume such decision-making duties, despite their lack of administrative training. This study examines the feasibility of using a computer model of a typical Community Mental Health Center (CMHC) as a training device, permitting clinical students to “manage” a complex social agency over a course of many months of simulated time. The system provides a valuable and interesting supplement to the usual training materials in psychology programs.     

Detection of a deficit in visual discrimination of pattern following lesions of anterior cortex: role of type of motivation.

6 albino rats were trained under appetitive motivation to perform diametrically opposed visual discriminations of pattern via opposite eyes. Small lesions were subsequently placed unilaterally in anterior neocortex. Following a period of post-surgical recovery, subjects were re-trained on the diammetrically opposed discriminations in alternating 10-trial blocks. Every subject made more post-surgical errors on the discrimination mediated by the eye contralateral to the lesion. Since albino rats have virtually complete decussation of the visual system, this indicates selective impairment in mediation of performance of pattern discrimination in the part of the lesioned hemispheres. Thus, findings previously obtained in studies involving aversive motivation are general to appetitively motivated tasks.     

Auditory contralateral induction: An early stage in binaural processing

Binaural interaction was studied using headphones presenting signals (tones or filtered speech) to one ear and noises of various spectral compositions to the other. Every half-second, the sides receiving the signal and noise were reversed. The noise was always perceived to alternate from side to side, but the signal appeared to be stationary and diffusely localized about the midsaggital plane when the noise contained the spectral components of the signal at appropriate intensity levels. This delateralization of a monaural signal results from a process called “contralateral induction” (CI). Additional observations indicate that CI corresponds to an early stage in binaural interaction which generally escapes notice because of further perceptual processing.