The effect of auditory and visual training on the mismatch negativity in schizophrenia

• Mismatch negativity (MMN) is evaluated in schizophrenia patients.
• Auditory or visual-spatial training or treatment-as-usual conditions is evaluated.
• MMN is assessed pre/post intervention and at two month follow-up.
• Training did not change MMN in schizophrenia patients.

BackgroundThe mismatch negativity (MMN) is an electrophysiological index of early auditory attention and has repeatedly been suggested to be associated with cognitive functioning. Despite the frequently reported finding of reduced MMN amplitude in schizophrenia, up to now, studies assessing the impact of perceptual discrimination training aiming to improve MMN measures in schizophrenia patients are scarce.MethodIn the present study, the effect of auditory training (AUD, n = 14) on the MMN was compared to that of visual-spatial training (VIS, n = 14) and a treatment-as-usual (TAU, n = 14) condition in schizophrenia patients. Training consisted of ten 50-min sessions over two weeks. Assessments took place before and after training and at a two-month follow-up. They comprised clinical measures and MMN recordings to frequency and duration deviant stimuli.ResultsThere was a significant main effect for type of stimulus deviance with a more negative MMN to frequency than duration deviants. In contrast to our hypotheses, we did not find training specific effects on MMN amplitude or latency.ConclusionThe visual, as well as the auditory training program failed to result in treatment related MMN changes in schizophrenia patients when compared to treatment-as-usual as a control condition. In contrast to reports in healthy subjects, the induction of training related MMN changes in schizophrenia patients may constitute a specific challenge and require more extensive training protocols.