how longitudinal study is linked with language development and inteligence in humans and reinforcement theories?
then compare humans with non-humans primates and explain how different studies will be compared to language and development studies.
A study was designed to examine the degree to which individual differences in gestural joint attention skills predicted language development among autistic children. A group of 15 autistic children (mean CA = 45 months) were matched with one group of mentally retarded (MR) children on mental age and another group of MR children on language age. These groups were administered the Early Social-Communication Scales. The latter provided measures of gestural requesting, joint attention, and social behaviors. The results indicated that, even when controlling for language level, mental age, or IQ, autistic children displayed deficits in gestural joint attention skills on two testing sessions that were 13 months apart. Furthermore, the measure of gestural nonverbal joint attention was a significant predictor of language development in the autistic sample. Other variables, including initial language level and IQ were not significant predictors of language development in this sample.
illiams syndrome (WS) is often cited as the prime example within developmental disorders of the dissociation of language from other cognitive skills, particularly from visuo-motor skills. This claim has been responsible for the challenges posed by this population to cognitive theories and to models of language acquisition. Two Hebrew-speaking children with WS were followed longitudinally for 18 months, from the first occurrences of two word combinations. Y was 3;9–5;3 and BT was 4;2–5;8 during data collection. Both children had an MLU of 1·8–2·8. The children's linguistic profiles were compared to the profiles of typically-developing (TD) children of similar MLU as well as to the profiles of 11 children with a variety of neurodevelopmental disorders (ND), matched on MLU. The profiles exhibited by the children with WS throughout the period of the study differed from the profiles seen in both control groups.