Altered Fronto-Temporal Functional Connectivity in Individuals at Ultra-High-Risk of Developing Psychosis.
BACKGROUND
The superior temporal gyrus (STG) is one of the key regions implicated in psychosis, given that abnormalities in this region are associated with an increased risk of conversion from an at-risk mental state to psychosis. However, inconsistent results regarding the functional connectivity strength of the STG have been reported, and the regional heterogeneous characteristics of the STG should be considered.


METHODS
To investigate the distinctive functional connection of each subregion in the STG, we parcellated the STG of each hemisphere into three regions: the planum temporale, Heschl's gyrus, and planum polare. Resting-state functional magnetic resonance imaging was obtained from 22 first-episode psychosis (FEP) patients, 41 individuals at ultra-high-risk for psychosis (UHR), and 47 demographically matched healthy controls.


RESULTS
Significant group differences (in seed-based connectivity) were demonstrated in the left planum temporale and from both the right and left Heschl's gyrus seeds. From the left planum temporale seed, the FEP and UHR groups exhibited increased connectivity to the bilateral dorsolateral prefrontal cortex. In contrast, the FEP and UHR groups demonstrated decreased connectivity from the bilateral Heschl's gyrus seeds to the dorsal anterior cingulate cortex. The enhanced connectivity between the left planum temporale and right dorsolateral prefrontal cortex was positively correlated with positive symptom severity in individuals at UHR (r = .34, p = .03).


CONCLUSIONS
These findings corroborate the fronto-temporal connectivity disruption hypothesis in schizophrenia by providing evidence supporting the altered fronto-temporal intrinsic functional connection at earlier stages of psychosis. Our data indicate that subregion-specific aberrant fronto-temporal interactions exist in the STG at the early stage of psychosis, thus suggesting that these aberrancies are the neural underpinning of proneness to psychosis.
Department of Brain and Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul, Republic of Korea.
Youngwoo Bryan
YB
Yoon
Department of Psychiatry, Seoul National University College of Medicine, Seoul, Republic of Korea.
Je-Yeon
JY
Yun
Department of Psychology, University of Pennsylvania, Philadelphia, Pennsylvania, United States of America; Institute of Human Behavioral Medicine, Seoul National University-Medical Research Center, Seoul, Republic of Korea.
Wi Hoon
WH
Jung
Department of Brain and Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul, Republic of Korea.
Kang Ik K
KI
Cho
Department of Psychiatry, Seoul National University College of Medicine, Seoul, Republic of Korea.
Sung Nyun
SN
Kim
Institute of Human Behavioral Medicine, Seoul National University-Medical Research Center, Seoul, Republic of Korea.
Tae Young
TY
Lee
Department of Psychiatry, Seoul National University College of Medicine, Seoul, Republic of Korea.
Hye Yoon
HY
Park
Department of Brain and Cognitive Sciences, College of Natural Sciences, Seoul National University, Seoul, Republic of Korea; Department of Psychiatry, Seoul National University College of Medicine, Seoul, Republic of Korea; Institute of Human Behavioral Medicine, Seoul National University-Medical Research Center, Seoul, Republic of Korea.
Jun Soo
JS
Kwon
D000328:Adult; D016022:Case-Control Studies; D063132:Connectome; D005260:Female; D005625:Frontal Lobe / Q000502:physiology* / Q000503:physiopathology; D006801:Humans; D008297:Male; D011618:Psychotic Disorders / Q000175:diagnosis / Q000503:physiopathology*; D013702:Temporal Lobe / Q000502:physiology* / Q000503:physiopathology