Threat Vigilance and Intrinsic Amygdala Connectivity

Abstract

A well documented amygdala-dorsomedial prefrontal circuit is theorized to promote attention to threat (‘threat vigilance’). Prior research has implicated a relationship between individual differences in trait anxiety/vigilance, engagement of this circuitry, and anxiogenic features of the environment (e.g. through threat-of-shock and movie-watching). In the present study, we predicted that—for those scoring high in self-reported anxiety and a behavioral measure of threat vigilance—this circuitry is chronically engaged, even in the absence of anxiogenic stimuli. Our analyses of resting-state fMRI data (N=639) did not, however, provide evidence for such a relationship. Nevertheless, in our planned exploratory analyses, we saw a relationship between threat vigilance behavior (but not self-reported anxiety) and intrinsic amygdala-periaqueductal gray connectivity. Here, we suggest this subcortical circuitry may be chronically engaged in hypervigilant individuals, but that the amygdala-prefrontal circuitry may only be engaged in response to anxiogenic stimuli.

Anxiety Shapes Amygdala-Prefrontal Dynamics During Movie-Watching

“…However, we suggest this is not the most plausible inference. In a separate study of CamCAN resting-state data using the same subjects, masks, and self-report/behavioral measures, we did not find evidence for differences in 'intrinsic functional connectivity' of amygdala-dmPFC circuitry (38). Moreover, this interpretation is in direct contrast to findings from threat-of-shock studies, which suggests individual differences emerge primarily when under a state of anxiety (2).…”

“…Therefore, the affective state elicited by suspenseful movies is likely multifaceted and more dynamic in nature than states evoked by threat-of-shock. Given the absence of these effects whilst at rest (38), we conclude that these individual differences are likely arising in response to the emotional context elicited by the movie.…”