The abnormalities of regional homogeneity in the resting-state functional magnetic resonance imaging were associated with impairment of attention function in deficit schizophrenia

Abstract

Objective To identify the characteristics of regional homogeneity (ReHo) of resting state brain activity and explore the association with the attention function in patients with deficit schizophrenia (DS). Method The patients were recruited with the diagnosis of schizophrenia according to DSM-Ⅳ criteria and divided into DS and non-deficit schizophrenia (NDS) sub-groups according to the Chinese version of the Schedule for the Deficit Syndrome (SDS). Thirty DS patients and 38 NDS patients, accompanying with 38 healthy controls (HC) who were age-, gender- and handedness-matched with the patients were enrolled. The severity of schizophrenic symptoms was evaluated by the Brief Psychiatric Rating Scale (BPRS), Scale for the Assessment of Negative Symptoms (SANS), and Scale for the Assessment of Positive Symptoms (SAPS). The Stroop color-word test were used to assess the attention function of subjects. All participants were scanned using a 3.0 T MRI system (GE HDx) for the resting-state fMRI data. The ReHo was calculated and compared between 3 groups. A partial correlation analysis was further performed to explore the relationships between these difference ReHo and attention function within the specific group. Results The Stroop colors, Stroop words, Stroop interference test scores were lower in both DS and NDS groups than HC group (F=28.615, 39.516, 21.898, all P<0.01) . DS patients showed lower scores in Stroop colors (26.5±12.9 vs. 35.6±11.5) , Stroop word (43.5±19.4 vs. 58.0±15.2) test than NDS patients (t=-2.949, P=0.012; t=-3.507, P=0.002) . Compared with NDS patients, DS patients showed significant increased ReHo in left and right lingual gyrus, left inferior temporal gyrus, right middle temporal gyrus/superior temporal gyrus, right middle occipital gyrus (t=4.70, 3.96, 4.22, 3.50, 4.44, all P<0.01, AlphaSim correction), and the significant decreased ReHo in left medial superior frontal gyrus/anterior cingulate gyrus, right triangular part of inferior frontal gyrus/middle frontal gyrus, left triangular part of inferior frontal gyrus (t=-3.24, -4.48, -3.47, all P<0.01, AlphaSim correction). The ReHo of left inferior frontal gyrus triangular was positively correlated with Stroop words test (r=0.451, P=0.016) and Stroop interference test (r=0.504, P=0.006) and showed no significant correlation with Stroop colors test (r=0.345, P=0.072). There was no significant correlation between the ReHo and Stroop test scores in other areas. NDS patients showed a negative result in correlation analysis. Conclusion Compared with NDS patients, DS patients may have more serious in sustained attention function, which might be related to brain activity regional homogeneity in left triangular part of inferior frontal gyrus. Key words: Schizophrenia; Magnetic resonance imaging; Regional homogeneity; Attention function