early visual processing for low spatial frequency fearful face is correlated with cortical volume in patients with schizophrenia

Jung Suk Lee,1 Gewnhi Park,2 Myeong Ju Song,3 Kee-Hong Choi,4 Seung-Hwan Lee5,6 1Department of Psychiatry, National Health Insurance Service Ilsan Hospital, Goyang, Republic of Korea; 2Department of Psychology, Azusa Pacific University, Azusa, CA, USA; 3Department of Neuropsychiatry, Seoul National University Hospital, 4Department of Psychology, Korea University, Seoul, Republic of Korea; 5Clinical Emotion and Cognition Research Laboratory, Goyang, Republic of Korea; 6Department of Psychiatry, Inje University, Ilsan-Paik Hospital, Goyang, Republic of Korea Abstract: Patients with schizophrenia present with dysfunction of the magnocellular pathway, which might impair their early visual processing. We explored the relationship between functional abnormality of early visual processing and brain volumetric changes in schizophrenia. Eighteen patients and 16 healthy controls underwent electroencephalographic recordings and high-resolution magnetic resonance imaging. During electroencephalographic recordings, participants passively viewed neutral or fearful faces with broad, high, or low spatial frequency characteristics. Voxel-based morphometry was performed to investigate brain volume correlates of visual processing deficits. Event related potential analysis suggested that patients with schizophrenia had relatively impaired P100 processing of low spatial frequency fearful face stimuli compared with healthy controls; patients’ gray-matter volumes in the dorsolateral and medial prefrontal cortices positively correlated with this amplitude. In addition, patients’ gray-matter volume in the right cuneus positively correlated with the P100 amplitude in the left hemisphere for the high spatial frequency neutral face condition and that in the left dorsolateral prefrontal cortex negatively correlated with the negative score of the Positive and Negative Syndrome Scale. No significant correlations were observed in healthy controls. This study suggests that the cuneus and prefrontal cortex are significantly involved with the early visual processing of magnocellular input in patients with schizophrenia. Keywords: event-related potential, visual processing, magnocellular, voxel-based morphometry, schizophrenia