Deficits in prosodic speech-in-noise recognition in schizophrenia patients and its association with psychiatric symptoms.

BACKGROUND

Uncertainty in speech perception and emotional disturbances are intertwined with psychiatric symptoms. How prosody embedded in target speech affects speech-in-noise recognition (SR) and is related to psychiatric symptoms in patients with schizophrenia (SCHs) remains unclear. This study aimed to examine the neural substrates of prosodic SR deficits and their associations with psychiatric symptom dimensions in patients with schizophrenia.

METHODS

Fifty-four SCHs and 59 healthy control participants (HCs) completed the SR task (participants were required to identify the contents of the target pseudo-sentences expressed in neutral, happy, sad, angry, fearful, and disgusted prosody by actors), positive and negative syndrome scale (PANSS) assessment, and magnetic resonance imaging scanning. We examined the deficits of the six prosodic SRs in schizophrenia patients and their associations with brain gray matter volume (GMV) and psychiatric symptoms.

RESULTS

Negative emotional (sad, angry, fearful, and disgusted) prosodies of the target sentences worsened SR across groups. Both participant groups had equal SR between the neutral and happy prosody conditions. Compared to the anger and disgusted conditions, SCHs and HCs had better SR under sad and fearful conditions. Better prosodic SR was associated with shorter duration and lower local shimmer of target sentences. A partial least squares (PLS) component of GMV (covering 47 brain regions with group differences) was associated with six prosodic SRs. The happy SR was associated with the PANSS total, negative, and general scores, adjusting for covariates.

CONCLUSIONS

Negative emotional prosodies of the target sentences dampened the recognition of the target sentences. The prosodic SR abnormalities in SCHs were associated with not only brain GMV reductions in the regions involved in the processing of sensorimotor, speech, and emotion but also with negative and general psychiatric symptoms. These findings suggest the possibility of improving negative symptoms by improving a happy SR in schizophrenia patients based on neuroplasticity.