Story recall under monaural and binaural conditions in psychiatric patients

It has been reported that a large proportion of patients with major psychiatric disorders can recall a short story better if they listen with one ear rather than the other (monaural asymmetry), and that binaural performance is worse than with the better ear alone (binaural inferiority). Blocking the poorer ear with an earplug is said to significantly improve speech comprehension in daily life. Because of the theoretical and practical significance of these reports, we have attempted a replication. Forty-four psychotic patients, primarily schizophrenic, were studied. We found a lower incidence of abnormal monaural asymmetry and binaural inferiority than was previously reported. The incidence remained low whether we considered the entire sample or subgroups defined by diagnosis, chronicity, or age. Retest reliability was poor. We also found that binaural superiority was as common as binaural inferiority, and concluded that the instances of relative binaural inferiority in our sample were primarily due to chance. Differences in methods, subject selection, or medication were considered, but did not clearly account for the discrepancies between our results and previous studies. Future research must focus on establishing the conditions determining reliability.