A developmental grammar for syllable structure in the production of child language.

The order of acquisition of Dutch syllable types by first language learners is analyzed as following from an initial ranking and subsequent rerankings of constraints in an optimality theoretic grammar. Initially, structural constraints are all ranked above faithfulness constraints, leading to core syllable (CV) productions only. Subsequently, faithfulness gradually rises to the highest position in the ranking, allowing more and more marked syllable types to appear in production. Local conjunctions of Structural constraints allow for a more detailed analysis.     

Accentuation and sensitization effects in the categorization of multifaceted stimuli

Categorization affects perceptions in ways that are assumed to underlie social stereotypes. Research on categorization, however, has focused either on very simple stimuli or on judgmental tasks that focus attention only on single dimensions. To more fully understand the role of categorization in social perception, it is important to examine its effects in the case of multifaceted stimuli and holistic judgments. In 3 studies, participants formed an impression of a focal category of multifaceted stimuli either by itself or in the context of another category. They then judged the typicality of exemplars to the focal category. Results showed that categorization in the presence of a context produced both accentuation and sensitization effects: Participants accentuated between-category differences on relevant dimensions, and they were less sensitive to exemplar differences on irrelevant dimensions.     

An examination of the effects of adult age on explicit and implicit learning of figural sequences

Memory for previously learned figural sequences and item-to-item covariations within figural sequences was examined under explicit and implicit instructional conditions in three age groups: young adults (17-23 years); middle-aged adults (35-45 years); and older adults (55-65 years). In Phase 1 of the experiment, the acquisition phase, half the subjects in each age group learned sequences of three to eight items in which the item-to-item changes conformed to an artificial grammar, and the other half of the subjects in each age group learned strings in which the item-to-item changes were nongrammatical. In Phase 2, the implicit/explicit test phase, subjects made forced-choice judgments about parts of the strings that they learned in Phase 1, under either explicit or implicit instructions. Analyses of Phase 2 data revealed that subjects in both instructional conditions used item-to-item covariations in making decisions about grammatical strings. However, use of previously learned covariations as well as the number of correct judgments about previously learned strings was greater in the explicit condition than in the implicit condition. An age-related deficit was found for explicit recognition of grammar-following sequences.     

Book reviews

Buckley, Key W. (1989). Mechanical man: John Broadeus Watson and the beginnings of Behaviorism. New York: Guilford Press. Pp. 293. ISBN 0-89862-744-3. $32.45/£18.00.

Colgan, P. (1989), Animal Motivation. New York and London: Chapman and Hall. Pp. 168. ISBN 0412-31850. £25.00 (hardback). ISBN 0412-31860, £10.95 (paperback).

Antinucci, F (Ed.) (1989). Cognitive structure and development in nonhuman prinates. Hillsdale, Nj: Laweence Erlbaum Associates, Inc. Pp. 266. ISBN 0-8058-0544. £16.50 (Hardback).

Parker, S.T. & Gibson, K.R. (Eds.) (1990). “Language” and intelligence in monkeys and apes. Cambridge: Cambridge University Press. Pp. 590. ISBN 0-521-38028-6. £40.00 (hardback).

Ley, Ronald (1990). A whisper of espionnage: Wolfgang Koehler and the apes of Tenerife. Garden City Park, NY: Avery Publoshing Corporation. Pp.264. ISBN 0-89529-432-x. $19.95.     

Potential for Suicide and Aggression in Delinquents at Juvenile Court in a Southern City

Because juvenile delinquents rarely communicate their wishes for suicide or homicide appropriately to busy caretakers, some means to identify those juveniles at greatest risk of acting out was sought. Psychological examiners in a Southern city individually questioned 263 Juvenile Court offenders about whether they wished to be dead, to kill themselves, or to kill others; and also about their existential experiences, thoughts and feelings. Taking the data associated with each wish, we used stepwise multiple logistic regression to pinpoint experiences, such as substance abuse, that were associated with a high likelihood of verbalizing a wish for destructive behavior. These results included sexual abuse as a risk factor and the presence of a mother or grandmother as a protective factor, and led to recommending education of caretakers and forming a screening test.     

Complexity Effects on Temporal Characteristics of Speech

In light of evidence that multiple-goal messages tend to be characterized by longer speech-onset latencies and higher pause-phonation ratios, Greene, McDaniel, Buksa, and Ravizza have suggested that it is not the pursuit of multiple goals, per se, that results in less fluent speech. Rather, these authors suggest that the slower speech production characteristic of such messages is the result of difficulties in assembling, or integrating, incompatible message features. Recent evidence, however, indicates that this account is incomplete and in need of revision. Toward this end, we advance a complexity account that suggests that there are increased processing-capacity and temporal demands associated with formulating and maintaining more complex message representations. The article then reports four experimental studies of this complexity account. Experiments 1 and 2 operationalize complexity as the amount of information to be communicated in a message. These studies indicate that complexity does affect pause-phonation ratio and average pause duration. Experiments 3 and 4 operationalize complexity as the coherence of the information to be conveyed in a message. The results of Experiment 4, but not Experiment 3, again indicated that complexity influences speech fluency. The results of these studies, then, are taken to provide considerable support for the complexity hypothesis.