Monitoring running-wheel movement using a serial mouse and an IBM-compatible system

A running-wheel-movement-detection system is described for use with an IBM-compatible system and a serial mouse. It is an adaptation of a system developed for use on a Commodore 64. The IBM-compatible system provides obvious advantages in speed, memory, data storage, and programming ease over the earlier Commodore 64 system.     

Gender typing of game choices and qualities of boys' play behavior

Relationships between gender choices and both movement patterns and social behavior were studied in first- and second-grade boys. Three-child, structured play groups were each composed of a boy whose mother saw him as high masculine in play preference on the Games Inventory, one seen as average, and one low masculine. Behaviors rated from videotapes included gender presentation variables, (e.g., leg separation), indicators of dominance and personal comfort (e.g.,range of movements), and indicators of social skill and peer response (e.g., interaction initiations). The low masculine boys were found to be the most feminine in their gender presentation, least dominant and aggressive, and the least socially successful of the boys. The greatest difference was between the low and the high masculine boys. The average masculine boys' scores were generally intermediate,but more similar to the low masculine boys on some variables and more similar to the high masculine boys on others. These conclusions apply to a group interaction play task, but not to an initial noninteractive play task. A secondary study in which girls played with low and average masculine boys is also reported. Here it was found that low masculine boys were generally intermediate between average boys and girls on gender presentation and dominance variables, but lowest of the groups on social interaction variables. The authors appreciate the comments of Peter Bentler and Spencer Thompson on a draft of this paper, the assistance of Laura McCain in running subjects and scoring tapes, and the expertise of Shu-Yeng Wong for computer programming.     

Accessibility of the voicing distinction for learning phonological rules

In three experiments a series of nonsense syllables ending in consonants was presented to adult subjects who had to discover or learn a rule classifying the syllables into two groups. The rule was based either on the voicing of the final consonants or on an arbitrary division of them. Subjects performed better with the voicing than with the arbitrary rule only when there was a straightforward relationship between the voicing rule and the plural formation rule in English or, more generally, when voicing assimilation with an added consonant was involved and attention was focused on the sound and articulation of the syllables. We conclude that the voicing distinction is not ordinarily accessible and that individuals easily learn and use phonological rules involving voicing assimilation because of articulatory constraints on the production of consonant clusters.     

The Pittsburgh Initial Neuropsychological Testing System (PINTS): A neuropsychological screening battery for psychiatric patients

This paper presents a new neuropsychological screening battery for psychiatric patients. It takes 1.5 to 2 hr to administer and briefly assesses general level of performance, memory, language skills, attention, and spatial-constructional abilities. Scoring and profiling are computerized. Initial validation based on discriminant analysis of a group of brain-damaged and non-brain-damaged psychiatric patients yielded a diagnostic accuracy level of 84.51%. Cross-validation on a different population led to a substantial attrition of classificatory accuracy, but cross-validation based on a comparison between two samples drawn from a homogeneous population yielded substantially less attrition. It was concluded that while the battery discriminates accurately in a homogeneous population, it is necessary to develop separate norms for populations varying in level of impairment.     

Syllable-internal structure and the sonority hierarchy: Differential evidence from lexical decision,naming, and reading

Treiman (1983) and others have argued that spoken syllables are best characterized not as linear strings of phonemes, but as hierarchically organized units consisting of an onset (initial consonant or consonant cluster) and a rime (the vowel and any following consonants) and that the rime is further divided into a peak or nucleus (the vowel) and a coda (the final consonants). It has also been argued that the sonority (or vowel-likeness) of the consonant closest to the peak, which is a function of its phonetic class, may have an effect on the strength of boundaries determined by the hierarchical division of the syllable (e.g., Treiman, 1984). We examined the evidence for syllable-internal structure and for sonority in two experiments that employed visually presented stimuli and lexical decision, naming, and reading tasks. Our results provide support for the breakdown of the rime into a peak and a coda and for an effect of the sonority of the postvocalic consonant on that break. This pattern occurred only in our lexical decision tasks, so the effect is assumed to be postlexical. We did not find an effect of the onset-rime boundary, perhaps because of an unanticipated effect of word frequency. Our results are discussed in terms of phonological coding in short-term memory.     

MENTAL ARITHMETIC IN AFRICA AND AMERICA: STRATEGIES,PRINCIPLES, AND EXPLANATIONS*

Mental arithmetic abilities were studied among unschooled African adults and American college students. A set of problems tested the use of the four basic arithmetic operations. Performance was analyzed for: strategies, implicit arithmetic principles, and explicit explanations of the principles. Both groups showed accurate mental arithmetic strategies related to the base ten structure of their native counting systems. The American students' mental strategies additionally made use of algorithms based on written place values. Several principles were implicit in the calculation strategies of both groups, and both used these principles to short-cut calculations. Though the African subjects did not, the American subjects did describe these abstract principles in explicit common language or algebraic expressions. Relationships between schooling and cognition are discussed.     

Duration discrimination in a series of rhythmic events

Duration discrimination of the last of a series of four clicks was investigated. Examination of psychophysical functions from eight subjects revealed evidence for a Weber’s law model relating discrimination to base interclick interval. Also, the point of subjective equality was seen to change reliably as a function of base rate.