Stimulus categorization by brain-damaged patients

Patients with localized insult to the right hemisphere, or to either the anterior or the posterior portion of the left hemisphere, as well as neurologically intact controls, evaluated stimuli on a seven-point rating scale for their degree of category membership. The stimuli were taken from one of two continua, one composed of fruit and vegetable items, and the other of items differing in hue and shape. Different subsets of stimuli provided different contexts for the judgments of category membership. The two left-hemisphere groups showed anomalies in categorizing the fruit and vegetable items but not the perceptual items, while the reverse was true for the right-hemisphere patients. Moreover, both left-hemisphere groups demonstrated context effects in their judgments of the representativeness of the fruit and vegetable items, but differed in the way in which they responded to changing contexts. Left posterior patients demonstrated weak category boundaries and even reclassified items. In contrast, patients with left anterior damage showed highly categorical responses and less differentiation of items within a category. All groups showed striking context effects in judgments of perceptual items in terms of changes in representativeness ratings and the location of a category boundary. Alternative interpretations of the results are offered.     

Gay women,men, and families in rural settings: Toward the development of helping communities

The urban biases of empirical research on gay men, women, and families have resulted in minimal knowledge about gay people in rural settings. The diversity of lives of rural gay women and men and the variety of patterns of meeting the challenges of rural living are described. Processes of help-seeking and help-giving are discussed and the need for a helping community of family, friends, and caring others is affirmed. Collaboration between rural gay people and rural community psychologists is suggested to promote the development of helping communities for gay people and thereby initiate a process of change in rural settings.     

Social learning and collective choice

To be pertinent to democratic practice, collective choice functions need not apply to all possible constellations of individual preference, but only to those that are humanly possible in an appropriate sense. The present paper develops a theory of humanly possible preference within the context of the mathematical theory of learning. The theory of preference is then exploited in an attempt to resolve Arrow's voting paradox through restriction of the domain of majoritarian choice functions.     

Separate verbal memory and naming deficits in attention deficit disorder and reading disability

In this study, verbal memory and naming abilities were investigated in reading disabled (RD) and control children who were characterized according to the presence or absence of attention deficit disorder (ADD). Results indicate that deficits in learning and memory for recently acquired information occur as a function of ADD rather than RD while deficits in naming are specific to RD rather than ADD. We conclude that ADD is a major source of additional and separate cognitive morbidity in RD children.     

Strategic hand use preferences and hemispheric specialization in tactual reading: impact of the demands of perceptual encoding

Four reading-related, information-processing tasks were administered to right-handed blind readers of braille who differed in level of reading skill and in preference for using the right hand or the left hand when required to read text with just one hand. The tasks were letter identification, same-different matching of letters that differed in tactual similarity, short-term memory for lists of words that varied in tactual and phonological similarity, and paragraph reading with and without a concurrent memory load of digits. The results showed interactions between hand preference and the hand that was actually used to read the stimulus materials, such that left preferrers were significantly faster and more accurate with their left hands than with their right hands whereas right preferrers were slightly but usually not significantly faster with their right hands than with their left hands. In all cases, the absolute magnitude of the left-hand advantage among left preferrers was substantially larger than the right-hand advantage among right preferrers. The results suggest that encoding strategies for dealing with braille are reflected in hand preference and that such strategies operate to modify an underlying but somewhat plastic superiority of the right hemisphere for dealing with the perceptual requirements of tactual reading. These requirements are not the same as those of visual reading, leading to some differences in patterns of hemispheric specialization between readers of braille and readers of print.     

Unilateral brain lesions in childhood: performance on the Revised Token Test

Comprehension of connected language as assessed by the Revised Token Test (RTT) was studied in 17 children with left hemisphere lesions (LL) and 11 with right hemisphere lesions (RL). LL children's significantly lower performance on several subtests than left controls (LC) matched by age, sex, race, and social class appeared to be related to the memory demands of these subtests rather than the limited syntactic elements assessed by the RTT. LL subjects requested significantly more command repetitions than control or RL subjects and when a repetition was not requested LL subjects often responded with immediacy. Although RL children tended to perform lower than right matched controls (RC), these differences were not significant nor readily related to either the memory or specific linguistic structures assessed. RL subjects required fewer command repetitions than LL subjects and exhibited a significantly greater frequency of immediate responses than controls or LL subjects. While based on few children, a trend for LL children with retrorolandic lesions to perform more poorly than those with left prerolandic lesions was suggested. No systematic difference in performance was apparent for children with left cortical vs. left subcortical lesions or among discrete sites of lesions within the right hemisphere. Children with left lesions prior to 1 year of age performed no better and, in several instances, significantly poorer than LL patients sustaining lesions after 1 year of age. Among RL subjects, those sustaining lesions after 1 year of age had greater difficulty than those with lesion onset before 1 year of age, especially on linguistic elements which seemed to be dependent upon visual spatial properties. Further studies are needed to evaluate the comprehension of more complex linguistic structures among children with unilateral brain lesions as well as to study the role of more basic factors such as memory and attention in explaining the present findings.     

Cognitive impairment in preschoolers: Identification using the personality inventory for children-revised

This study evaluated the clinical validity of the Intellectual Screening, Development, and Achievement scales of the Personality Inventory for Children-Revised (PIC-R), as well as the newly derived PIC-R Factor IV scale, in identifying cognitive impairment in a clinic-referred sample of preschoolers. The clinical validity of these PIC-R subscales was also compared to that of the Minnesota Child Development Inventory (MCDI). The results showed that the PIC-R scales and Factor IV were reasonably successful in identifying cognitively impaired preschoolers, but much less successful in identifying cognitively normal preschoolers. Overall, the MCDI was the most successful in correctly identifying the preschoolers' cognitive status.     

Separating the redundancy of voicing from nasality in American English

This paper reports the results of a study designed to separate the voicing redundancy from nasality in American English and to determine their individual saliencies. Sixty-seven subjects judged the similarity of nonnasal pairs versus nasal pairs of CV and VC nonsense syllables on a 5-point magnitude-estimation task. The 80 stimuli were constructed to control and to demand subjects' cognitive strategies for coping with redundancy rather than experimental manipulation of the data. They were developed from the consonantal repertoire of / b d g m n p t k / paired with the vowels / i a u /, totaling 72 pairs of dyads. Eight additional stimuli of similar structure, testing multifeature and identity contrasts, were included to monitor the validity of the experimental procedure. Results indicated that (a) speech redundancy can be circumvented cognitively, (b) nasality was more salient (different) than voicing, and (c) a recency effect was found. These findings are discussed in reference to existing data.