Neurophysiological Face Processing Deficits in Patients With Chronic Schizophrenia: An MEG Study

Naotoshi Ohara; Yoji Hirano; Naoya Oribe; Shunsuke Tamura; Itta Nakamura; Shogo Hirano; Rikako Tsuchimoto; Takefumi Ueno; Osamu Togao; Akio Hiwatashi; Tomohiro Nakao; Toshiaki Onitsuka

doi:10.3389/fpsyt.2020.554844

Neurophysiological Face Processing Deficits in Patients With Chronic Schizophrenia: An MEG Study

Front Psychiatry. 2020 Sep 3:11:554844. doi: 10.3389/fpsyt.2020.554844. eCollection 2020.

Authors

Naotoshi Ohara^{1

2}, Yoji Hirano^{1

3}, Naoya Oribe^{1

4}, Shunsuke Tamura¹, Itta Nakamura¹, Shogo Hirano¹, Rikako Tsuchimoto^{1

5}, Takefumi Ueno^{1

4}, Osamu Togao⁶, Akio Hiwatashi⁷, Tomohiro Nakao¹, Toshiaki Onitsuka¹

Affiliations

¹ Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
² Medical Corporation Seiryokai, Mimamigaoka Hospital, Fukuoka, Japan.
³ Department of Psychiatry, Harvard Medical School, Boston, MA, United States.
⁴ Division of Clinical Research, National Hospital Organization, Hizen Psychiatric Medical Center, Saga, Japan.
⁵ Center for Health Sciences and Counseling, Kyushu University, Fukuoka, Japan.
⁶ Department of Molecular Imaging and Diagnosis, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.
⁷ Department of Clinical Radiology, Graduate School of Medical Sciences, Kyushu University, Fukuoka, Japan.

Abstract

Background: Neuropsychological studies have revealed that patients with schizophrenia (SZ) have facial recognition difficulties and a reduced visual evoked N170 response to human faces. However, detailed neurophysiological evidence of this face processing deficit in SZ with a higher spatial resolution has yet to be acquired. In this study, we recorded visual evoked magnetoencephalography (MEG) and examined whether M170 (a magnetic counterpart of the N170) activity deficits are specific to faces in patients with chronic SZ.

Methods: Participants were 26 patients with SZ and 26 healthy controls (HC). The M170 responses to faces and cars were recorded from whole-head MEG, and global field power over each temporal cortex was analyzed. The distributed M170 sources were also localized using a minimum-norm estimation (MNE) method. Correlational analyses between M170 responses and demographics/symptoms were performed.

Results: As expected, the M170 was significantly smaller in the SZ compared with the HC group in response to faces, but not to cars (faces: p = 0.01; cars: p = 0.55). The MNE analysis demonstrated that while the M170 was localized over the fusiform face area (FFA) in the HC group, visual-related brain regions other than the FFA were strongly activated in the SZ group in both stimulus conditions. The severity of negative symptoms was negatively correlated with M170 power (rho = -0.47, p = 0.01) in SZ. Within HC, there was a significant correlation between age and the M170 responses to faces averaged for both hemispheres (rho = 0.60, p = 0.001), while such a relationship was not observed in patients with SZ (rho = 0.09, p = 0.67).

Conclusion: The present study showed specific reductions in the M170 response to human faces in patients with SZ. Our findings could suggest that SZ is characterized by face processing deficits that are associated with the severity of negative symptoms. Thus, we suggest that social cognition impairments in SZ might, at least in part, be caused by this functional face processing deficit.

Keywords: M170; fusiform gyrus; human faces; magnetoencephalography; schizophrenia.