Like and cross modality responses in normal and subnormal children

Experiments which investigated response behaviour in imbeciles and normals, in a conflict situation between a general verbal instruction and direct stimuli, were carried out. It was found that combined verbal-motor responses did not give better results than either verbal or motor responses alone. Results in accordance with the general instruction were significantly better if the subnormal children responded in a different modality from the one in which the signals were given. While normals and imbeciles differed markedly in their ability to perform the tasks in like-modality trials, this difference was less apparent in cross modality responses.     

Choice reaction times for skilled responses

Two kinds of choice reaction time experiments are reported, both of which make use of a highly overlearned sensori-motor response. When a response is required for each stimulus presented, no increase in reaction time occurs as a function of the number of alternative stimuli available. It is proposed that the increase in choice reaction times commonly thought to accompany an increase in the number of alternative choices provided reflects the unpractised state of the responder. When a response is required for only one out of n possible stimuli, a slight but consistent increase in reaction time takes place with an increase in the number of alternatives. An analogy is drawn between the second experiment and a vigilance task and an expectancy hypothesis is invoked to explain the results.     

Aversive control of self-injurious behavior in a psychotic boy

Two studies are reported which indicate how quickly and effectively chronic self-injurious behavior was controlled in a 9-yr-old blind psychotic boy. In the first study, the self-injurious responses were punished by contingent withdrawal of human physical contact. In the second study, response-contingent electric shock was employed.