Selective adaptation of English consonants using real speech

Most English consonant-vowel (CV) syllables have other CV syllables embedded within them. For example, splicing sufficient energy from the onset of [k^ha] yields [p^ha], splicing into [ma] or [va] yields [ba], and splicing into [?a] yields [da]. We spliced successively longer segments from naturally spoken CV syllables to produce sequences of CV syllables which varied in discrete acoustic steps from [k^ha] to [p^ha], from [?a] to [da], from [ma] to [ba], from [fa] to [ba], and from [va] to [ba]. Random presentation of syllables in each series resulted in identification functions with typically sharp phoneme boundaries. For example, in the seven-syllable [?a]-[da] series (where [?a] was the original or first syllable), there were98% [?a] responses to Syllable 3, but only 12% [?a] responses (88% [da] responses) to Syllable 5. Following the identification test, subjects listened to 180 repetitions of either the first or last syllable in the test series, and were again required to identify randomly presented syllables from the test series. A shift in the phoneme boundary toward the repeated (adapting) syllable was observed for 11 of the 12 repeated syllables. Repeated presentation of [?a], for example, resulted in fewer [?a] responses to syllables in the [?a]-[da] series, compared to performance on the previous identification test. Likewise, repeated listening to [da] resulted in a decrease in [da] responses. Adaptation was selective in that syllables near the phoneme boundary were most affected by the adapting syllable. A shift in the phoneme boundary was also observed for two different continua when the adapting stimulus contained an acoustic feature identical to syllables in the test series. Thus, selective adaptation was found along a [ma]-[ba] continuum following repeated presentation of [na] and following repeated presentation of nasal resonance removed from its syllable context. A second major result, observed in five different experiments, was an asymmetrical adaptation effect. A greater shift in the phoneme boundary was observed following repeated presentation of the first syllable in each series (e.g., [?a]) than for the final embedded syllable (e.g., [da]). The results were discussed in terms of two different models of-selective adaptation.     

Adolescents who apparently are invulnerable to drug, alcohol, and nicotine use

As part of a large survey of addictive behavior in high school students, a group of 43 girls and 34 boys was identified who denied any use of drugs, alcohol, or tobacco. These apparently invulnerable adolescents were compared to the rest of the "user" sample on the remaining items of the questionnaire. The invulnerable students reported generally better physical and mental health and academic achievement. They also indicated a significantly lower rate of similar problems in their parents.     

Infant temperament and performance on the Bayley Scales of Infant Development at 4, 8, and 12 months of age

Infants were assessed with the Rothbart Infant Behavior Questionnaire (an objective measure of infant temperament based on maternal reports) and the complete Bayley Scales of Infant Development (BSID) at 4, 8, and 12 months of age. Activity level was related to BSID performance at each age with babies who obtained higher scores rated as more active. Activity level was also related to the infants' behavior during the test administration at 8 and 12 months. A negative relation was found between smiling and laughter and the mental development index at 8 and 12 months. These data suggest that aspects of infant temperament as assessed by maternal report share a small amount of variance with BSID performance and the amount of shared variance increases with age.     

Causal attributions, perceived consequences of unemployment, and perceptions of employment prospects among adolescents in New Zealand

The present study investigated the causal attributions and perceived consequences of unemployment, as well as perceptions of employment prospects, among high school students in New Zealand. A sample of Form 4 (Grade 9) boys (M age 14.3 years) and girls (14.4 years) and a sample of Form 6 and 7 (Grades 11 and 12) boys (16.9 years) and girls (16.6 years) were tested. No sex or age differences were found in students' causal attributions about unemployment. Societal factors were judged as the most important cause for unemployment. Luck was considered the least important reason. Form 4 students placed a greater emphasis on economic consequences, whereas Form 6 and 7 students regarded social consequences as more important. The consistency in the present findings and those from studies in other countries suggests that cross-cultural similarities do exist in adolescents' perceptions of unemployment.     

Processes of inference during sentence encoding

Four experiments were designed to determine whether implicit instruments are “computed” and stored during sentence encoding. Subjects read pairs of related sentences and indicated when they understood the second member of each pair. In Experiment 1, response times were longer for test sentences that, relative to the antecedent, mentioned implicit rather than explicit instruments. Experiment 2 revealed this difference to be stable over a range of reading times and two phases of practice. The results were interpreted as suggesting that the inferences in question are not computed, or at most, are partially drawn during encoding In Experiment 3, the procedure was employed to distinghish four degrees of relation between propositions and the inferences they permit. Experiment 4 examined the agent, patient, and instrument cases. It was shown that subjects need more time to verify both true and false inference tests than to verify their direct counterparts.     

Motivation effects of attributions, expectancy, and achievement motivation during the learning of a novel motor task

Several cognitive motivational theories including achievement motivation, attribution theory, and a test of expectancy for future success were linked to explain and predict psychomotor performance. Sixty high- and 60 low-need-achieving male high school students were randomly placed into success and failure feedback conditions, and performance scores on a lever-positioning apparatus were assessed. Following each block of performance trials, fictitious feedback in the form of success and failure information was given, and then each subject rated attribution and expectancy questionnaires. Expectancies for future performance improved more following success than after failure and were generally predicted by attributions to stable elements. Although trends were present, performance scores were unaffected by these cognitive beliefs. However, a significant prediction of performance was obtained when stepwise multiple regression procedures were used with constant error as the criterion variable. The factors of expectancy and luck significantly predicted performance.