Perception of stress contrasts in semantic and nonsemantic contexts by children

Journal of Psycholinguistic Research - Using 140 subjects (20 children each from kindergarten through the sixth grade), this study followed the developmental trends of children on two tasks...     

A quantitative assessment of the effects of malnutrition on behavioral development in laboratory mice

The aim of this study was to compare the effects of malnutrition on behavioral development in mice with those due to heredity obtained in a previous study. To this end behavioral development was assessed using a developmental time scale which allowed comparison of the two studies. Pregnant B6D2F1/J mice were maintained on either a protein restricted or normal protein diet from Day 7 to Day 24 postconception, at which time the low protein group was returned to the normal diet until behavioral testing at Day 32. Behavioral development in the control group replicated the values obtained in previous studies, whereas the malnourished pups were retarded by 1.4 days. This was of the same order of magnitude as that reported previously for maternal inbreeding. Measures of maternal and pup body weight at birth, Day 24 and Day 32 indicated that although the malnourished animals were initially significantly lighter in weight they had recovered by Day 32. Litter size however, declined between birth and time of behavioral testing in the malnourished group.     

The interactions of hyperactive and normal boys with their fathers and mothers

This study examined the interactions of fathers and mothers with their hyperactive and normal children during both free-play and task periods. Eighteen hyperactive and 18 normal boys were observed interacting separately with their mothers and fathers in a playroom setting. Behavioral observations indicated, with minor exceptions, that fathers and mothers did not differ in their interactions with their sons. Substantial differences were found between hyperactive and normal boys in their parent-child interactions, particularly during the task setting. Hyperactive boys were generally less compliant and their parents more directive than normal parent-child dyads. Methodological problems are discussed that may have precluded the emergence of differences between mothers and fathers in their interactions with their sons.     

Children's memory for the premises in a transitive measurement task assessed by elicited and spontaneous justifications

Two experiments were conducted to test the hypothesis that children who fail to make the transitive inference do so because they do not recall the premises. In the first, 32% of the children who made an incorrect inference in a transitive measurement task justified their inference by the correct premises. In the second, where spontaneous justification was encouraged by testing dyads on the same task, the percentage was 15%. In neither experiment were there children who justified an incorrect inference by incorrect premises or a solo premise. The results are interpreted as showing that not only can incorrect inferers store the correct premises, but that they can also retrieve them adequately. The pattern and outcome of interactions between nontransitive and transitive inferers in the dyad sessions parallelled similar studies with conserver-nonconserver dyads. Both sets of data were taken as reinforcing the commonality between transitivity and the other concrete operations.     

A Role for the Human Amygdala in Recognizing Emotional Arousal From Unpleasant Stimuli

Functional neuroimaging and lesion-based neuropsychological experiments have demonstrated the human amygdala's role in recognition of certain emotions signaled by sensory stimuli, notably, fear and anger in facial expressions. We examined recognition of two emotional dimensions, arousal and valence, in a rare subject with complete, bilateral damage restricted to the amygdala. Recognition of emotional arousal was impaired for facial expressions, words, and sentences that depicted unpleasant emotions, especially in regard to fear and anger. However, recognition of emotional valence was normal. The findings suggest that the amygdala plays a critical role in knowledge concerning the arousal of negative emotions, a function that may explain the impaired recognition of fear and anger in patients with bilateral amygdala damage, and one that is consistent with the amygdala's role in processing stimuli related to threat and danger.