TY - JOUR
T1 - Brain mediators of cardiovascular responses to social threat. Part I
T2 - Reciprocal dorsal and ventral sub-regions of the medial prefrontal cortex and heart-rate reactivity
AU - Wager, Tor D.
AU - Waugh, Christian E.
AU - Lindquist, Martin
AU - Noll, Doug C.
AU - Fredrickson, Barbara L.
AU - Taylor, Stephan F.
N1 - Funding Information:
We would like to thank Niall Bolger for helpful discussions on path analysis, and the authors of SPM software for making it freely available. This paper was made possible with the support of grant funding from NSF 0631637 (T.W.), NIH Grant MH076136 (T.W.), NIH Grant MH59615 (B.L.F.), a pilot grant from the UM fMRI lab to S.T./C.W., positive psychology microgrant to C.W. and dissertation thesis grant to C.W.
PY - 2009/9
Y1 - 2009/9
N2 - Social threat is a key component of mental "stress" and a potent generator of negative emotions and physiological responses in the body. How the human brain processes social context and drives peripheral physiology, however, is relatively poorly understood. Human neuroimaging and animal studies implicate the dorsal medial prefrontal cortex (MPFC), though this heterogeneous region is likely to contain multiple sub-regions with diverse relationships with physiological reactivity and regulation. We used fMRI combined with a novel multi-level path analysis approach to identify brain mediators of the effects of a public speech preparation task (social evaluative threat, SET) on heart rate (HR). This model provides tests of functional pathways linking experimentally manipulated threat, regional fMRI activity, and physiological output, both across time (within person) and across individuals (between persons). It thus integrates time series connectivity and individual difference analyses in the same path model. The results provide evidence for two dissociable, inversely coupled sub-regions of MPFC that independently mediated HR responses. SET caused activity increases in a more dorsal pregenual cingulate region, whose activity was coupled with HR increases. Conversely, SET caused activity decreases in a right ventromedial/medial orbital region, which were coupled with HR increases. Individual differences in coupling strength in each pathway independently predicted individual differences in HR reactivity. These results underscore both the importance and heterogeneity of MPFC in generating physiological responses to threat.
AB - Social threat is a key component of mental "stress" and a potent generator of negative emotions and physiological responses in the body. How the human brain processes social context and drives peripheral physiology, however, is relatively poorly understood. Human neuroimaging and animal studies implicate the dorsal medial prefrontal cortex (MPFC), though this heterogeneous region is likely to contain multiple sub-regions with diverse relationships with physiological reactivity and regulation. We used fMRI combined with a novel multi-level path analysis approach to identify brain mediators of the effects of a public speech preparation task (social evaluative threat, SET) on heart rate (HR). This model provides tests of functional pathways linking experimentally manipulated threat, regional fMRI activity, and physiological output, both across time (within person) and across individuals (between persons). It thus integrates time series connectivity and individual difference analyses in the same path model. The results provide evidence for two dissociable, inversely coupled sub-regions of MPFC that independently mediated HR responses. SET caused activity increases in a more dorsal pregenual cingulate region, whose activity was coupled with HR increases. Conversely, SET caused activity decreases in a right ventromedial/medial orbital region, which were coupled with HR increases. Individual differences in coupling strength in each pathway independently predicted individual differences in HR reactivity. These results underscore both the importance and heterogeneity of MPFC in generating physiological responses to threat.
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U2 - 10.1016/j.neuroimage.2009.05.043
DO - 10.1016/j.neuroimage.2009.05.043
M3 - Article
C2 - 19465137
AN - SCOPUS:67651070597
SN - 1053-8119
VL - 47
SP - 821
EP - 835
JO - NeuroImage
JF - NeuroImage
IS - 3
ER -