Describes a study which used a discrimination-learning procedure to compare the ability of language-disordered and normal children to modify hypotheses. In a series of two-dimensional learning set and orthogonal problems, all children reached learning set criteria quickly; on orthogonal problems, language-disordered children performed…

This experiment examined the effects of reinforcement probability on resistance to change of remembering and response rate. Pigeons responded on a two- component multiple schedule in which completion of a variable-interval 20-s schedule produced delayed matching-to-sample trials in both components. Each session included four delays (0.1 s, 2 s, 4…

Three experiments investigated discrimination and memory of 5.5-month-olds for videotapes of women performing different activities (blowing bubbles, brushing hair, brushing teeth) or static displays after a 1-minute and a 7-week delay. Findings demonstrate the attentional salience of actions over faces in dynamic events to 5.5-month-olds. Findings…

Two studies with 33 reading-disabled and 31 non-reading-disabled second through fourth graders indicate that young disabled readers may not be able to hold phonemic information in their memories long enough to make adequate discrimination of phonological information within syllables. (SLD)

This is a partial report of a longitudinal investigation designed to assess the psychological effects of an experimentally conducted day care program on children during the first 30 months of life. The experimental subjects were Chinese and Caucasian children from working and middle class families who were cared for at a special group care center…