Twice a week observation of five infants' vocalizations during the first 30 weeks of life showed that hearing impaired infants displayed different language patterns than normally hearing infants. Developmental differences in vocal activity were observed by six weeks of age, suggesting that hearing impaired infants may differ from unimpaired infants earlier than has been believed.

Four groups of eight rats were trained to press each of two bars for reward delayed 120 sec. A different set of distinctive cues prevailed between bar press and food depending on which bar was pressed. For experimental subjects shocks were then introduced following each response to the preferred bar. The response-shock interval was 1.5,12, or 96 sec. depending on group assignment. Experimental subjects' preference shifted from the shock bar; preference remained the same for no-shock controls. The rate of changes was a negative function of delay of shock, but final percentage of responses to the nonshock bar was the same for all delays. The results were interpreted as supporting the hypothesis that delay of punishment as such has no effect on choice at asymptote.

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