The encoding of rate and talker information during phonetic perception

The acoustic structure of the speech signal is extremely variable due to a variety of contextual factors, including talker characteristics and speaking rate. To account for the listener’s ability to adjust to this variability, speech researchers have posited the existence of talker and rate normalization processes. The current study examined how the perceptual system encoded information about talker and speaking rate during phonetic perception. Experiments 1–3 examined this question, using a speeded classification paradigm developed by Garner (1974). The results of these experiments indicated that decisions about phonemic identity were affected by both talker and rate information: irrelevant variation in either dimension interfered with phonemic classification. While rate classification was also affected by phoneme variation, talker classification was not. Experiment 4 examined the impact of talker and rate variation on the voicing boundary under different blocking conditions. The results indicated that talker characteristics influenced the voicing boundary when talker variation occurred within a block of trials only under certain conditions. Rate variation, however, influenced the voicing boundary regardless of whether or not there was rate variation within a block of trials. The findings from these experiments indicate that phoneme and rate information are encoded in an integral manner during speech perception, while talker characteristics are encoded separately.     

Introductory psychology laboratories using graphic simulations of virtual subjects

Graphical simulations of the behavior of virtual subjects in laboratory or field microworlds were developed to teach research principles to introductory psychology students. Students conduct studies in laboratory classes, assuming the primary role of being an experimenter. Microworld modules were designed to foster the flexible exploration of important steps in the research process, including hypothesis generation, research planning and design, behavioral observation or testing, and data summarization and analysis. The modules were designed to impart a sense of behavioral “presence” so that students would obtain an appreciation of realistic behavioral observation and of testing methodologies. Microworlds that have been developed include infant preferential looking (cognitive processes), courting behavior of fireflies, personality test development, working memory, operant conditioning, single-cell recording of sensory function, and testing of brain-damaged people. Principles that guided the development of software modules and laboratory class exercises are discussed.     

Balm in Gilead: Spiritual Dimensions in Counseling African American Women

The authors describe African American cultural and spiritual traditions that are the bedrock for therapeutic work with this population. Through the use of a clinical case, they link African American women's emotional issues with healing interventions borrowed from their rich heritage of religious and spiritual rituals and practices.     

Timing in Eyeblink Classical Conditioning and Timed-Interval Tapping

Abstract—The cerebellum is implicated in interval timing for diverse tasks including eyeblink classical conditioning (EBCC) and repetitive tapping. We examined performance on both tasks across identical intervals ranging from 325 to 550 ms. In five weekly sessions, 23 participants used a different interval each week, both as the target for tapping and as the delay interval in EBCC. Changes in variability as a function of the tapping or delay interval were assessed using regression analyses. The slope for repetitive tapping was comparable to two measures of temporal acuity in EBCC, onset and peak latency of the conditioned response. Each of 80 additional participants was assessed in one session at one of four tapping and delay intervals. Results were similar to those observed in the repeated measures group. These findings provide further evidence that EBCC and repetitive tapping utilize common mechanisms for representing temporal information.     

Talker continuity and the use of rate information during phonetic perception

Research has shown that speaking rate provides an important context for the perception of certain acoustic properties of speech. For example, syllable duration, which varies as a function of speaking rate, has been shown to influence the perception of voice onset time (VOT) for syllableinitial stop consonants. The purpose of the present experiments was to examine the influence of syllable duration when the initial portion of the syllable was produced by one talker and the remainder of the syllable was produced by a different talker. A short-duration and a long-duration /bi/-/pi/ continuum were synthesized with pitch and formant values appropriate to a female talker. When presented to listeners for identification, these stimuli demonstrated the typical effect of syllable duration on the voicing boundary: a shorter VOT boundary for the short stimuli than for the long stimuli. An /i/ vowel, synthesized with pitch and formant values appropriate to a male talker, was added to the end of each of the short tokens, producing a new hybrid continuum. Although the overall syllable duration of the hybrid stimuli equaled the original long stimuli, they produced a VOT boundary similar to that for the short stimuli. In a second experiment, two new /i/ vowels were synthesized. One had a pitch appropriate to a female talker with formant values appropriate to a male talker; the other had a pitch appropriate to a male talker and formants appropriate to a female talker. These vowels were used to create two new hybrid continua. In a third experiment, new hybrid continua were created by using more extreme male formant values. The results of both experiments demonstrated that the hybrid tokens with a change in pitch acted like the short stimuli, whereas the tokens with a change in formants acted like the long stimuli. A fourth experiment demonstrated that listeners could hear a change in talker with both sets of hybrid tokens. These results indicate that continuity of pitch but not formant structure appears to be the critical factor in the calculation of speaking rate within a syllable.     

Familiarity and pop-out in visual search

In this paper, we report that when the low-level features of targets and distractors are held constant, visual search performance can be strongly influenced by familiarity. In the first condition, a was the target amid as distractors, and vice versa. The response time increased steeply as a function of number of distractors (82 msec/item). When the same stimuli were rotated by 90° (the second condition), however, they became familiar patterns— and —and gave rise to much shallower search functions (31 msec/item). In the third condition, when the search was for a familiar target, (or ), among unfamiliar distractors, (or ), the slope was about 46 msec/item. In the last condition, when the search was for an unfamiliar target, (or ), among familiar distractors, s (or s), parallel search functions were found with a slope of about 1.5 msec/item. These results show that familiarity speeds visual search and that it does so principally when the distractors, not the targets, are familiar.     

The Induction of Self-Reliance: An Experimental Study of Independence in the Face of Failure*

The development of dependency, rather than autonomy, in professional and paraprofessional helping relationships represents a practical and theoretical problem. In the present research an attempt is made experimentally to examine this issue from the viewpoint of the self-perception hypothesis. From this perspective, immersion in the successful helping dyad was expected to foster an increased belief in self as other-reliant, and, through cognitive balance, a lessened belief in self as self-reliant. The fiidings indicate that such different dimensions of help as intensity, duration, and choice variously affect these attributions to self, and that these attributions in turn affect the strength of behavioral independence when failure is encountered outside the helping dyad. Some practical and theoretical implications are discussed concerning the role of induction from self-performance in mapping self-related beliefs.