Using neuroplasticity-based auditory training to improve verbal memory in schizophrenia

Abstract

Objective: Impaired verbal memory in schizophrenia is a key rate-limiting factor for functional outcome, does not respond to currently available medications, and shows only modest improvement after conventional behavioral remediation. The authors investigated an innovative approach to the remediation of verbal memory in schizophrenia, based on principles derived from the basic neuroscience of learning-induced neuroplasticity. The authors report interim findings in this ongoing study.

Method: Fifty-five clinically stable schizophrenia subjects were randomly assigned to either 50 hours of computerized auditory training or a control condition using computer games. Those receiving auditory training engaged in daily computerized exercises that placed implicit, increasing demands on auditory perception through progressively more difficult auditory-verbal working memory and verbal learning tasks.

Results: Relative to the control group, subjects who received active training showed significant gains in global cognition, verbal working memory, and verbal learning and memory. They also showed reliable and significant improvement in auditory psychophysical performance; this improvement was significantly correlated with gains in verbal working memory and global cognition.

Conclusions: Intensive training in early auditory processes and auditory-verbal learning results in substantial gains in verbal cognitive processes relevant to psychosocial functioning in schizophrenia. These gains may be due to a training method that addresses the early perceptual impairments in the illness, that exploits intact mechanisms of repetitive practice in schizophrenia, and that uses an intensive, adaptive training approach.

Figures

FIGURE 1

Stimuli in Exercise 1 of Auditory Training Given to Patients With Schizophrenia to Improve Verbal Memorya a The learner must perform a time-order judgment task and identify each of two successive frequency modulation sweeps as either “up” (sweep on left) or “down” (sweep on right). Sweep duration and interstimulus interval are modified parametrically as the learner’s performance improves.

FIGURE 2

Change in Cognitive Performance in Patients With Schizophrenia After 50 Hours of Computerized Auditory Training or 50 Hours of Computer Games aSignificant difference between groups (p<0.01, repeated-measures ANOVA). bSignificant difference between groups (p<0.05, repeated-measures ANOVA). cNonsignificant difference between groups (p=0.10, repeated-measures ANOVA).