Early Auditory Processing Predicts Efficient Working Memory Functioning in Schizophrenia

Early auditory processing (EAP) deficits have been consistently documented in individuals
diagnosed with schizophrenia (SZ). However, a relationship between EAP and executive attention has
not been confirmed in SZ versus healthy controls (HC). The current study aimed to demonstrate that
unlike HC, in SZ patients, auditory change-detection event-related potentials (ERPs) are significantly
associated with executive working memory (WM) functioning. Additionally, correlational analyses
investigated the relationships between patients’ auditory ERPs, WM performance, and schizophrenia
symptom severity scores. We examined verbal WM accuracy associated with “executive-control”
prefrontal cortex mechanisms and EAP ERPs under midline prefrontal electrodes in 12 SZ patients
versus 12 demographically matched HC. Mismatch negativity (MMN) amplitudes and latencies in
SZ patients were not significantly different from HC, however, their verbal WM performance was
significantly impaired versus HC. Importantly, prolonged MMN latencies in the SZ group were
correlated with betterWMaccuracy. In the HC group,WMaccuracy was unrelated to MMN latencies.
Patients’ MMN parameters were unrelated to schizophrenia symptom-domain severity. However,
patients’ WM RTs and accuracy were significantly related to illness severity and negative symptom
severity, respectively. Therefore, inefficient sensory excitation related to EAP timing may underlie
poor executive verbal WM functioning and might indirectly exacerbate the severity of negative
symptoms in SZ. Treatments targeting prefrontal cortex dysfunction in schizophrenia are discussed