Korean J Biol Psychiatry.  2017 Nov;24(4):225-234. 10.0000/kjbp.2017.24.4.225.

Alterations of Cortical Folding Patterns in Patients with Bipolar I Disorder: Analysis of Local Gyrification Index

• Lee J
• Han KM
• Won E
• Lee MS
• Ham BJ

• KMID: 2398929
• DOI: http://doi.org/10.0000/kjbp.2017.24.4.225

Abstract

OBJECTIVES
Local gyrification reflects the early neural development of cortical connectivity, and is regarded as a potential neural endophenotype in psychiatric disorders. Several studies have suggested altered local gyrification in patients with bipolar I disorder (BD-I). The purpose of the present study was to investigate the alterations in the cortical gyrification of whole brain cortices in patients with BD-I.
METHODS
Twenty-two patients with BD-I and age and sex-matched 22 healthy controls (HC) were included in this study. All participants underwent T1-weighted structural magnetic resonance imaging (MRI). The local gyrification index (LGI) of 66 cortical regions were analyzed using the FreeSurfer (Athinoula A. Martinos Center for Biomedical Imaging). One-way analysis of covariance (ANCOVA) was used to analyze the difference of LGI values between two groups adjusting for age and sex as covariates.
RESULTS
The patients with BD-I showed significant hypogyria in the left pars opercularis (uncorrected-p = 0.049), the left rostral anterior cingulate gyrus (uncorrected-p = 0.012), the left caudal anterior cingulate gyrus (uncorrected-p = 0.033). However, these findings were not significant after applying the multiple comparison correction. Severity or duration of illness were not significantly correlated with LGI in the patients with BD-I.
CONCLUSIONS
Our results of lower LGI in the anterior cingulate cortex and the ventrolateral prefrontal cortex in the BD-I group implicate that altered cortical gyrification in neural circuits involved in emotion-processing may contribute to pathophysiology of BD-I.

Keyword

Local gyrification index; Bipolar disorder; Ventrolateral prefrontal cortex; Anterior cingulate cortex; Emotion-processing neural circuit

MeSH Terms

Bipolar Disorder
Brain
Broca Area
Endophenotypes
Gyrus Cinguli
Humans
Magnetic Resonance Imaging
Prefrontal Cortex