Some consequences of stimulus variability on speech processing by 2-month-old infants.

The present study explores how stimulus variability in speech production influences the 2-month-old infant's perception and memory for speech sounds. Experiment 1 focuses on the consequences of talker variability for the infant's ability to detect differences between speech sounds. When tested with high-amplitude sucking (HAS) procedure, infants who listened to versions of a syllable, such as [symbol: see text], produced by 6 male and 6 female talkers, detected a change to another syllable, such as [symbol: see text], uttered by the same group of talkers. In fact, infants exposed to multiple talkers performed as well as other infants who heard utterances produced by only a single talker. Moreover, other results showed that infants discriminate the voices of the individual talkers, although discriminating one mixed group of talkers (3 males and 3 females) from another is too difficult for them. Experiment 2 explored the consequences of talker variability on infants' memory for speech sounds. The HAS procedure was modified by introducing a 2-min delay period between the familiarization and test phases of the experiment. Talker variability impeded infants' encoding of speech sounds. Infants who heard versions of the same syllable produced by 12 different talkers did not detect a change to a new syllable produced by the same talkers after the delay period. However, infants who heard the same syllable produced by a single talker were able to detect the phonetic change after the delay. Finally, although infants who heard productions from a single talker retained information about the phonetic structure of the syllable during the delay, they apparently did not retain information about the identity of the talker. Experiment 3 reduced the range of variability across talkers and investigated whether variability interferes with retention of all speech information. Although reducing the range of variability did not lead to retention of phonetic details, infants did recognize a change in the gender of the talkers' voices (from male to female or vice versa) after a 2-min delay. Two additional experiments explored the consequences of limiting the variability to a single talker. In Experiment 4, with an immediate testing procedure, infants exposed to 12 different tokens of one syllable produced by the same talker discriminated these from 12 tokens of another syllable.(ABSTRACT TRUNCATED AT 400 WORDS)     

Retraining Displaced Workers: Factors Affecting Success in Training Programs

In this study 21 displaced workers were interviewed regarding factors affecting their participation in training programs funded by the Job Training Partnership Act. Differences between program participants and nonparticipants, differences among program participants, and differences among nonparticipants were identified.     

The Career Exploration Inventory: Expanding Options for the Unemployed

The Career Exploration Inventory, an innovative interest inventory that measures work and leisure interests throughout the life span, can be used by employment counselors to assist their clients in the exploration of the interaction of work and leisure interests.     

Effects of Response Set on the Infrequent Response Index of the Strong Interest Inventory

Associations of two different response sets on the Infrequent Response Index of the Strong Interest Inventory (SII) were examined. In one, participants responded to each item randomly; in the other, participants deliberately misrepresented their responses. The finding of scores higher than those proposed in the SII manual for the Infrequent Response Index suggests an alternative interpretation of this critical index.