||Temporal differentiation of response duration in children of different ages: Developmental changes in relations between verbal and nonverbal behavior.
18 children (aged 4.5, 7, or 11 yrs) were assigned to 1 of 2 groups at each age level. In the verbal probe condition (VPC), Ss in a buttonpress contingency session were asked after each trial a question about the contingency requirement. In the interview condition, Ss received an identical task followed by an interview. Level of adaptation to a duration contingency increased with age for VPC Ss only. VPC 11 yr olds showed a strong correlation between accurate temporal differentiation and number of verbalizations on response duration or timing. Although 11-yr-old children may produce rule-governed behavior under verbal control, the behavior of younger children may be controlled by reinforcement contingencies despite highly developed verbal repertoires. (PsycINFO Database Record (c) 2007 APA, all rights reserved)