Assessing Trial-to-Trial Variability in Auditory ERPs in Autism and Schizophrenia.

Researchers studied brain responses to sounds in people with autism, schizophrenia, and typical development. They found that both autism and schizophrenia groups showed more inconsistent brain responses from trial to trial compared to typical individuals. This suggests that sensory processing (how the brain handles sounds) may be less stable in both conditions. People with autism actually showed stronger initial brain responses than those with schizophrenia, but both groups had more variable responses overall.

This 2023 study examined trial-to-trial variability (TTV) in auditory brain responses among individuals with autism, schizophrenia, and neurotypical controls using mismatch negativity (MMN) measurements. The research found that autism showed the largest MMN responses while schizophrenia showed the smallest, compared to controls. Both autism and schizophrenia demonstrated greater trial-to-trial variability in neural response amplitudes compared to neurotypical individuals, suggesting increased neural instability in sensory processing. However, no differences were found in inter-trial coherence (timing consistency).

These findings indicate that sensory processing instability may be a shared characteristic between autism and schizophrenia, potentially involving multiple neural mechanisms underlying sensory abnormalities in both conditions.

Results suggest that measuring neural variability could potentially serve as a biomarker for sensory processing difficulties in autism. Understanding shared neural mechanisms with schizophrenia may inform treatment approaches. However, clinical applications require validation studies with larger samples and correlation with behavioral measures.

Sample size not reported, limiting assessment of statistical power. Study type unclear. Abstract provides limited methodological details. Findings based on single neurophysiological measure (MMN). Cross-sectional design prevents causal inferences about neural variability and sensory symptoms.

Sensory abnormalities are characteristic of autism and schizophrenia. In autism, greater trial-to-trial variability (TTV) in sensory neural responses suggest that the system is more unstable. However, these findings have only been identified in the amplitude and not in the timing of neural responses, and have not been fully explored in schizophrenia. TTV in event-related potential amplitudes and inter-trial coherence (ITC) were assessed in the auditory mismatch negativity (MMN) in autism, schizophrenia, and controls.

MMN was largest in autism and smallest in schizophrenia, and TTV was greater in autism and schizophrenia compared to controls. There were no differences in ITC. Greater TTV appears to be characteristic of both autism and schizophrenia, implicating several neural mechanisms that could underlie sensory instability.