Music during learning of a tactual-spatial task affects later response generalization

Equal numbers of men and women learned a finger maze, with half of the subjects initially using their right hands and the other half using their left hands. To reach criterion, subjects receiving music in the ear ipsilateral to the hand used required more trials than did those receiving no music. Furthermore, when the right hand ran the maze, music played to the ipsilateral ear also delayed learning, compared with music played contralaterally. Binaural music delayed learning when the left hand was used but not when the right hand was used. Possible causes of these effects are suggested. When subjects switched hands and relearned the maze, the number of trials to criterion depended on the group subjects were in during initial learning and not on the group they were in during the hand reversal (response generalization) trials. Although the music condition used determined the effect of music on initial learning and on response generalization, some evidence is presented that indicates that the two effects are not entirely interdependent and that they may even involve different mechanisms.     

Choice, experience, and the generalized matching law

Five pigeons were exposed to different pairs of concurrent variable-interval, variable-interval schedules on nine experimental conditions of 30 sessions each. For every session, the parameters of the generalized matching equation were computed for the first five, six, seven, eight, and nine experimental conditions. The exponent a, both for response and time distribution, tended to decrease with increases in number of experimental conditions and to increase with number of sessions per condition, but values of k (bias) varied unsystematically. When the subjects were exposed to five new pairs of schedules, with 55 sessions per condition, the findings were confirmed. Data from the literature on the generalized matching law suggest that the variability of exponent values may be explained in part by the use of naive or experienced subjects in different investigations and by the variability in number of experimental conditions and in number of sessions per condition.     

The power distance reduction hypothesis on a level of reality

An experiment and a replication were conducted, testing the hypothesis that the smaller the actual power distance between a subject and a more powerful other, the stronger the tendency to reduce the power distance between them. Power distance was created by placing the subject in a group of three people plus a supervisor. In the condition of large power distance, the three workers had identical functions. Small power distance was induced by placing the subject at an intermediary power level, above the two workers, but below the supervisor. Two other conditions of small power distance were manipulated in order to assess the effects of the timing of power promotion and the perception of the promotion as caused by the subject's task competence. During the course of the experiment, the supervisor left unexpectedly and the subject had the option of taking over the supervisory role or letting one of his co-workers assume it. In the first experiment, subjects who were at a large power distance chose to replace the supervisor significantly less frequently than subjects in the three small power-distance conditions. The small power-distance conditions did not differ from each other. The replication with two small power-distances conditions produced the same results. Both experiments took place in a natural setting.     

Discourse in aphasia: Integration deficits in processing reference

The present study investigated moderately impaired aphasic subjects' ability to integrate information across sentences by having them identify antecedents for ambiguous pronouns in brief narratives. In order to disambiguate the pronouns, the subjects had to consult either textual cues and/or extratextual cues. In addition, the subjects' ability to retrieve factual information was measured by having them identify explicitly stated noun referents. The results show that the aphasic subjects had significant difficulty using textual cues to resolve referents when the referents were not readily accessible through world knowledge. The patients had little difficulty interpreting referents which were recoverable from world knowledge or were stated explicitly. The explanatory power of world knowledge effects, grammatical class effects, memory effects, and linguistic integration effects in accounting for the deficit pattern observed is considered.     

A longitudinal study of an adult with aphasia: Considerations for research and therapy

This paper described investigation and therapy carried out over a one year period with an adult aphasic patient characterized by severe impairment of auditory comprehension. A deblocking technique was used to reintegrate the mechanisms for correlating sound and meaning. The visual mode of presentation of linguistic material was used both to provide a stable representation of speech units and to allow reinforcement of auditory representations. The patient was given tasks of repetition, reading aloud, and sequencing, using progressively more complex material. The behavior of the patient gives support to the viability of the theoretical constructs of linguistics: this can be seen in the differential processing of function words vs. content words, and in the orderly progression of improvement through stages explicable as the recovery of well-defined and hierarchically dependent subcomponents of linguistic organization.     

Sensory feedback in the learning of a novel motor task

The role of different forms of feedback is examined in learning a novel motor task. Five groups of ten subjects had to learn the voluntary control of the abduction of the big toe, each under a different feedback condition (proprioceptive feedback, visual feedback, EMG feedback, tactile feedback, force feedback). The task was selected for two reasons. First, in most motor learning studies subjects have to perform simple movements which present hardly any learning problem. Second, studying the learning of a new movement an provide useful information for neuromuscular reeducation, where patients often also have to learn movements for which no control strategy exists. The results show that artificial sensory feedback (EMG feedback, force feedback) is more powerful than "natural" (proprioceptive, visual, and tactile) feedback. The implications of these results for neuromuscular reeducation are discussed.