Interhemispheric coordination and focused attention in chronic and acute schizophrenia

Groups of chronic and acute schizophrenics, together with controls, were given a story comprehension task where material was presented either binaurally or monaurally. A significant right ear advantage was found in the scores of the acute patients but not in those of chronics or controls. Similarly, acutes, in contrast to all other subjects, demonstrated a binaural performance decrement relative to their preferred ear in the monaural condition. A second experiment showed that acute schizophrenics, in contrast to an earlier finding with chronics, were no better at detecting targets in dichotically presented word lists when the targets occurred in one ear only than when they could occur in either ear. It is suggested that this inability to focus attention on one ear, in the presence of competing stimulation to the other, was responsible for the story comprehension result.