A reexamination of duplex perception evoked by intensity differences

Duplex perception is a term used to describe the simultaneous evocation of phonetic and nonphonetic percepts, a phenomenon held by some to reveal the operation of a specialized module for phonetic perception. In a widely cited experiment by Whalen and Liberman (1987), duplex percepts were created by replacing the third formant transition in a synthetic syllable with a sinusoidal tone glide and manipulating the level of the glide relative to the rest of the syllable. We discuss this study, and report four experiments. The first two made a systematic estimate of the “duplexity threshold”—the tone glide level at which a chirp-like sound could be heard as well as the speech-like syllable. In the third and fourth experiments, we used the results of the first to repeat and extend the experimental procedures in the original Whalen and Liberman study. We discuss the differences in outcome, and conclude that our results may be explained without the need to invoke a specialized phonetic module.     

TEACHING MENSTRUAL CARE TO MENTALLY RETARDED WOMEN: ACQUISITION,GENERALIZATION, AND MAINTENANCE

We evaluated a training package designed to teach menstrual care skills to five mild to severely mentally retarded women. Three specific skill areas (changing stained underwear; sanitary napkin; and both stained underwear and sanitary napkin) were task analyzed and taught in a sequential manner. Results of a multiple-baseline design across women indicated that the training package was successful in teaching these skills; the women continued to perform the skills during naturally occurring menses up to 5 months following termination of the study.     

Information in speech: observations on the perception of [s]-stop clusters

A series of experiments is reported that investigated the pattern of acoustic information specifying place and manner of stop consonants in medial position after [s]. In both production and perception, information for stop place includes the spectrum of the fricative at offset, the duration of the silent closure interval, the spectral relationship between the frequency of the stop release burst and the following periodically excited formants, and the spectral and temporal characteristics of the first formant transition. Similarly, the information for stop manner includes the duration of silent closure, the frequency of the first formant at the release, the magnitude of the first formant transition, and the proximity of the second and third formants at release. A relationship was shown to exist in perception between the spectral characteristics of the first formant and the duration of the silent closure required to hear a stop. This appears to reciprocate the covariation of these parameters in production across different places of articulation and different vocalic contexts. The existence of perceptual sensitivity to a wide range of the acoustic consequences of production questions the efficacy of accounts of speech perception in terms of the fractionation of the signal into elemental acoustic cues, which are then integrated to yield a phonetic percept. It is argued that it is inappropriate to ascribe a psychological status to cues whose only reality is their operational role as physical parameters whose manipulation can change the phenotic interpretation of a signal. It is suggested that the metric of the information for phonetic perception cannot be that of the cues; rather, a metric should be sought in which acoustic and articulatory dynamics are isomorphic.     

MEASURING CLIENT GAINS FROM STAFF-IMPLEMENTED PROGRAMS

Confidence in the adequacy with which staff implement training programs requires an analysis of the impact on the client. In two experiments, measures were devised to reflect this impact. In the first, a measure of the consistency with which clients participated in a toilet-training program revealed their participation to be erratic. Consistent participation occurred after a public display of the consistency of participation was introduced. In Experiment II, detailed measures were devised to reflect the client's performance during the implementation of two physical-therapy programs: range-of-motion and ambulation. Additionally, standardized measures of the benefits that accrued from their participation in these programs were devised. Improvements in both measures were slight and unstable during a condition of immediate feedback (supervisor praise) to staff but substantial improvements were obtained with the addition of a public display of the client's performance.     

Teaching pedestrian safety skills to young children: an analysis and one-year followup

Twenty-four elementary school children in grades K-3 participated in a study to teach six street-crossing skills: (1) wait at curb, (2) look all ways, (3) watch vehicle distance, (4) walk, (5) continue to look, and (6) use crosswalk. The effects of an instructional package implemented on the street corner were evaluated using a multiple-baseline design across two groups of six children at each of two schools. Rapid acquisition of pedestrian skills was evident at both schools. Average skill levels improved from 44% during baseline to 97% after training at School A and from 21% to 86% at School B. Data taken at a second street at each school were used to assess setting generality of safety behaviors. A one-year followup of 14 children indicated that pedestrian safety skills either maintained at high levels or could be quickly recovered from intermediate levels after remedial training. This research represents a first step in the solution of just one of the many community problems involving safety-deficient settings.     

Choice for others and the perception of control

There has been an increasing emphasis in psychology on the perception of control over one's environment and its effect on behavior and performance. In the present experiment, subjects were allowed to choose material they would like to learn if given the opportunity, or allowed to choose material for others to learn. Their learning of a nonchosen (forced) set of materials was then examined and compared with that of subjects given no opportunity to choose at all. It was found that the choice-for-self condition led to better performance than either the choice-for-other condition or the nochoice (forced) condition. However, when an additional group of subjects was given the opportunity to choose for others and their personal involvement was augmented by emphasizing their willingness to choose, their performance was enhanced relative to subjects offered no choice. The results were discussed in terms of motivational benefits stemming from perceived control.This report is based on a thesis submitted by the first author to the Graduate School at Virginia Polytechnic Institute and State University in partial fulfillment of the requirements for the M.S. degree. The research was supported in part by a grant from the U.S. Army Research Office to the second author and by the Behavioral Research Directorate of the U.S. Army Human Engineering Laboratory. It may be reproduced in full or in part for any purpose of the United States Government.     

Supervenience and Physicalism

Discussion of the supervenience relation in the philosophical literature of recent years has become Byzantine in its intricacy and diversity. Subtle modulations of the basic concept have been tooled and retooled with increasing frequency, until supervenience has lost nearly all its original lustre as a simple and powerful tool for cracking open refractory philosophical problems. I present a conceptual model of the supervenience relation that captures all the important extant concepts (and suggests a few new ones) without ignoring the complexities uncovered during work over the past two decades. I test my analysis by applying it to the problem of defining physicalism, concluding that the thesis of physicalism is best captured by the conjunction of two supervenience relations. This revised version was published online in June 2006 with corrections to the Cover Date.     

Examining the Link Between Exercise and Positive Relationship Events in Clinical Couples

This study contributes to the literature on potential interventions couple therapists can use outside therapy for couples. We examine this research question: Are couples that exercise on a given day more likely to experience positive events in their relationship that day? Participants were 33 couples in a treatment-as-usual setting who completed the Daily Diary of Events in Couple Therapy for up to the first 28 days they are in therapy. Multinomial logistic regression showed increased women's daily hours of exercise were significantly associated with an increased report of daily positive events for both men and women. Men's daily hours of exercise were not significantly related to daily positive events reported by either partner.