The interaction of pronunciation rules and lexical representations in reading aloud

Two experiments examined the role of pronunciation rules and of lexical information in pronouncing letter strings. In Experiment 1, subjects pronounced pseudowords varying in the strength of the rules needed to pronounce them, as well as in the availability of a lexical model. In Experiment 2, the stimuli were words varying in rule strength and in usage frequency. The pronunciation times from both experiments displayed an interaction between rules and lexical information: When the rules necessary were strong, the relative availability of lexical information was less important than when the rules were weak. The results were discussed with respect to both traditional dual-process models of pronunciation and models proposing the use of lexical analogies.     

Recent stressful life events and young children's school adjustment

A group of 211 first-to fourth-grade children who had experienced one or more recent stressful life events were compared to a demographically matched sample of 211 children who had not experienced such events on measures of school adjustment problems and competencies. Stressful life events were found to be associated with the presence of more serious school adjustment problems and fewer competencies. Those associations were strongest for children who had experienced multiple recent stressful events. The importance of preventive interventions for this at-risk group was emphasized and future research steps in the area were considered.     

Effects of social isolation in adulthood on odor preferences and urine-marking in male rats

Male rats isolated for 60 days in adulthood spent less time investigating odors of females and urine-marked less over these odors than did males kept in groups of three. Isolated males did not differ from grouped males in their responses to odors of unfamiliar males or their own odors. After social experience the isolated males showed an increase in urine-marking but no change in odor preferences. Individual housing therefore appears to alter olfactory communication in the same way that it does other social behaviors and these changes may be mediated by the same mechanisms.     

Development of learning-disabled and normally achieving children's causal attributions

The causal attributions of learning-disabled (LD) and normally achieving (NA) children in grades 3 through 8 were compared. Attributions were measured by two scales that asked children to attribute hypothetical academic failure situations to factors that were either within (e.g., insufficient effort) or beyond (e.g., insufficient ability, blaming others) their control. Consistent with a learned helplessness hypothesis, LD girls, regardless of age, were more likely than NA children to attribute their failures to factors beyond their control. In contrast, LD boys' explanations for their failures paralleled those of NA children. That is, with increasing age the LD boys were more likely to attribute their failures to insufficient effort. Explanations and implications of sex differences in developmental patterns of LD children's causal attributions are discussed.The authors wish to thank Ruth Dusseault and Betty Wallace for their help in conducting this research. We also wish to thank the teachers, children, and administrators from the Leon County Schools for their cooperation.     

Correlations between glucose metabolic rates in brain regions of healthy male adults at rest and during language stimulation

This study examines the effect of different behavioral conditions on patterns of correlation between regional cerebral metabolic rates for glucose. Cerebral glucose metabolism was determined with positron emission tomography and (11C)-deoxyglucose in 29 normal subjects between the ages of 23 and 55. Seventeen subjects were studied in an unstimulated (resting) condition and 12 subjects during a phoneme monitoring language stimulation. Partial correlation coefficients, controlling for whole brain glucose metabolism, were calculated for pairs of metabolic rates in 14 cortical and 2 subcortical regions. Both stimulated and unstimulated subjects showed statistically significant correlations between left and right hemisphere homologs. The stimulated subjects also showed significant within-hemisphere correlations between left but not right hemisphere regions. These included left perisylvian regions classically associated with language functions (left inferior frontal, left superior temporal and left transverse temporal cortical regions) as well as other regions. Significant correlations between left regions and a right superior temporal region were also found. In general, these findings show a pattern of cross-hemisphere symmetry at rest and of hemisphere asymmetry during stimulation. Moreover, the asymmetry observed during stimulation appears to be superimposed upon a pattern of cross-hemisphere symmetry similar to that observed in the unstimulated state.