Citation

Lipp I, Evans CJ, Lewis C, Murphy K, Wise RG, Caseras X. PLoS One 2015; 10(3): e0120101.

Affiliation

MRC Centre for Neuropsychiatric Genetics and Genomics, Institute of Psychological Medicine and Clinical Neurosciences, Cardiff University, Cardiff, United Kingdom.

Copyright

(Copyright © 2015, Public Library of Science)

DOI

10.1371/journal.pone.0120101

PMID

25811453

Abstract

The inhibitory neurotransmitter GABA plays a crucial role in anxiety and fear, but its relationship to brain activation during fear reactions is not clear. Previous studies suggest that GABA agonists lead to an attenuation of emotion-processing related BOLD signals in the insula. The aim of this study was to investigate the relationship between GABA concentration and fear-related BOLD responses in this region. In 44 female participants with different levels of fearfulness, GABA concentration in the left insula was measured using a GABA+ MRS acquisition during rest; additionally, BOLD signals were obtained during performance of a fear provocation paradigm. Fearfulness was not associated with GABA+ in the left insula, but could predict fear-related BOLD responses in a cluster in the left anterior insula. The BOLD signal change in this cluster did not correlate with GABA+ concentration. However, we found a significant positive correlation between GABA+ concentration and fear-related BOLD responses in a different cluster that included parts of the left insula, amygdala and putamen. Our findings indicate that low insular GABA concentration is not a predisposition for fearfulness, and that several factors influence whether a correlation between GABA and BOLD can be found.

Language: en