Auditory processing deficits in schizophrenia: Evidence from a novel task.

BACKGROUND Deficits in basic auditory processing (BAP) are features of schizophrenia (SCZ), contributing to cognitive and psychosocial dysfunction. While pitch discrimination tasks are widely used to assess BAP, conventional tasks conflate auditory processing deficits with impairments in echoic memory. We designed a novel Simultaneous Binaural Pitch Discrimination (SBPD) task to focus more on BAP by eliminating temporal separation between stimuli.

METHODS We administered the SBPD task to 42 patients with SCZ and 42 demographically matched healthy controls (HC). Pure tone pairs were presented simultaneously binaurally by dichotic headphones, requiring participants to judge pitch identity/differences without echoic memory involvement. Accuracy and reaction time were examined and analyzed. Relationships between clinical variables (age at diagnosis, illness duration and antipsychotic dosage) and task performance were assessed.

RESULTS Patients exhibited significantly lower accuracy than controls (57.87 % vs. 74.33 %, t = -3.688, p < 0.001; Cohen's d = -0.62) and longer reaction times (2111.61 ± 447.18 ms vs. 1906.04 ± 413.88 ms, t = 2.414, P = 0.020, d = 0.40).

CONCLUSIONS We employed a newly designed task and found basic auditory processing deficits in patients compared to healthy individuals. Future studies should investigate the stability and neural mechanisms of binaural integration deficits, particularly brainstem dysfunction implicated in abnormal auditory brainstem responses (ABRs) in SCZ.