Frequency ratios and the discrimination of pure tone sequences

We examined the effect of frequency ratios on the discrimination of patterns of alternating pure tones (ABABA). Listeners heard a repeating pattern presented in transposition (same frequency ratios between successive tones, different absolute frequencies) and were required to indicate when the pattern changed (different frequency ratios and absolute frequencies). Changes from patterns with simple frequency ratios to those with more complex ratios were more readily detected than were changes from complex ratios to simpler ratios.     

WHY A BRAIN CAPABLE OF LANGUAGE EVOLVED ONLY ONCE: PREFRONTAL CORTEX AND SYMBOL LEARNING

Abstract. Language and information processes are critical issues in scientific controversies regarding the qualities that epitomize humanness. Whereas some theorists claim human mental uniqueness with regard to language, others point to successes in teaching language skills to other animals. However, although these animals may learn names for things, they show little ability to utilize a complex framework of symbolic reference. In such a framework, words or other symbols refer not only to objects and concepts but also to sequential and hierarchical relationships with other symbols. This process is essential to human mental operations, including language, mathematics, and music. In humans, these operations may have coevolved with the prefrontal area of the cerebral cortex, which is proportionately much larger in humans than in other animals and more intricately linked with other areas of the brain. Analysis of the structure and function of the prefrontal area suggests that it is centrally involved in the operation of higher-order associative relationships involving the subordination of one set of associations to another. This alternate learning strategy apparently appeared at the cost of certain sensory, motor, or limbic abilities. The payoff was symbolic thinking. Humans thus are unique among species, not just for their highly developed language ability but for their odd style of thinking and learning.     

Social attitudes of schizophrenics

The Wilson-Patterson Conservatism Scale was given to 34 schizophrenic and 34 non-schizophrenic patients in a Dutch mental hospital. The absence of liberal-scoring schizophrenics was interpreted as consistent with the theory that the social withdrawal seen in chronic schizophrenia represents a strategy for coping with stimulus overload. Internal consistency analysis of C scale performance indicated that this test might be used to assess thought disorder in much the same way as the Bannister and Fransella Grid Test, but a great deal more economically. Furthermore, the questionnaire permits a more detailed examination of the source of inconsistency than does the repertory grid method.     

Alcohol breath tests: Criterion times for avoiding contamination by “mouth alcohol”

Using either a gas chromatography or an infrared absorption technique, series of blood alcohol concentrations (BACs) determined by breath tests were obtained from human subjects immediately subsequent to their having only oral contact with beverages ranging in ethyl alcohol concentration from 4% to 95% +. Times for total dissipation of mouth alcohol residuals to a level of practical nonsignificance ranged from 10 to 19 min. Dissipation rates were an inverse and approximately exponential function of the ethyl alcohol concentration of the beverage and were greatly shortened by rinsing the mouth with warm (34°C) water prior to testing. The results are discussed in terms of their relevance to the methodology of a number of research studies employing BAC breath-testing equipment.     

An examination of the effect of six types of error perturbation on fifteen clustering algorithms

An evaluation of several clustering methods was conducted. Artificial clusters which exhibited the properties of internal cohesion and external isolation were constructed. The true cluster structure was subsequently hidden by six types of error-perturbation. The results indicated that the hierarchical methods were differentially sensitive to the type of error perturbation. In addition, generally poor recovery performance was obtained when random seed points were used to start theK-means algorithms. However, two alternative starting procedures for the nonhierarchical methods produced greatly enhanced cluster recovery and were found to be robust with respect to all of the types of error examined.     

Personality and Daily Experience: The Promise and the Challenge

This special issue of the Journal of Personality is devoted to personality and daily experience. Through historical analysis of the daily event literature, empirical inquiry, and methodological and statistical commentary, the contributors to this issue convey both the possibilities and the problems of studying everyday life. These articles demonstrate how people's dispositions, goals, and commitments can influence daily emotional well-being and health, their inner experience, their reactions to events, and perhaps even which events they encounter. The introduction of personality to the study of daily experience holds the promise of enriching our studies of both.     

Mental shock can produce retrograde amnesia

Subjects in three experiments saw a short film of a mentally shocking event in which a young boy is violently shot in the face. Compared to other subjects who saw a nonviolent version of the same film, those who saw the mentally shocking version showed poorer retention of the details of the film. Retention was poorer whether measured by recognition or recall. Furthermore, impaired memory occurred only when the event was mentally upsetting, and not when it was merely unexpected but not upsetting. These results suggest that mentally shocking episodes may disrupt the lingering processing necessary for full storage of information in memory.