Characterising the anxiogenic network from functional connectivity analysis of the CO2 challenge model
Year: 2024
Type: article
Abstract: The CO 2 challenge model (CCM) is a gas inhalation paradigm that provides precisely controlled anxiety induction in experimental settings. Despite its potential as an experimental model of anxiety, our understanding of the neural effects of the CCM is incomplete. This study employs resting-state functional magnetic resonance imaging (rs-fMRI) to explore functional connectivity (FC) changes underlying the CCM. Following a preliminary CO 2 tolerance assessment, participants completed an MRI session that included three rs-fMRI scans: during inhalation of control air (pre and post), and during a 6% CCM exposure. Here, we confirm that 6% CCM is a tolerable anxiogenic model in the MRI setting. We demonstrate that a transient CCM-induced increase in subjective anxiety is associated with an increase in FC within limbic and anxiety-related regions, with the insula emerging as a central node in this altered connectivity pattern. Further analysis revealed a significant correlation between the levels of subjective anxiety and enhanced FC between the brainstem and medial frontal cortex, highlighting the dynamic role of the brainstem in response to CO 2 -induced anxiety. These findings underscore the value of combining CCM and rs-fMRI to characterise the neural mechanisms of anxiety, with important implications for evaluating potential therapeutic interventions.
Source: Scientific Reports
Authors: Daniel Graham, Santra Mathew, Jonathan Marsden, Alastair D. Smith, Gary Smerdon, Stephen D. Hall
Institutions: University of Plymouth, Plymouth Hospital
Language: English
Subfield: Cognitive Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: gold
Estimated APC paid: $2,590
Funder: Plymouth University
OpenAlex ID: W4404723891