Reduced γ-Aminobutyric Acid and Glutamate+Glutamine Levels in Drug-Naïve Patients with First-Episode Schizophrenia but Not in Those at Ultrahigh Risk

Table 2

Means (SD) for tissue composition and spectral quality in the mPFC region in first-episode schizophrenia (FES), subjects at ultrahigh risk for psychosis (UHR), and healthy controls (HC).

Group	Tissue composition			Spectral quality
	CSF fraction	GM fraction	WM fraction	FWHM (ppm)	SNR
HC	0.12 (0.030)	0.56 (0.032)	0.32 (0.049)	0.11 (0.04)	22.43 (5.13)
UHR	0.12 (0.028)	0.56 (0.038)	0.31 (0.046)	0.11 (0.03)	21.90 (4.29)
FES	0.11 (0.027)	0.56 (0.040)	0.32 (0.047)	0.11 (0.02)	20.81 (3.12)

GM: grey matter; WM: white matter; CSF: cerebrospinal fluid; FWHM: full-width at half maximum; SNR: signal-to-noise ratios.