Fear bradycardia and activation of the human periaqueductal grey

Hermans, Erno J.; Henckens, Marloes J. A. G.; Roelofs, Karin; Fernández, Guillén

doi:10.1016/j.neuroimage.2012.10.063

Cited by 113 publications

(113 citation statements)

References 71 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…If from one side cerebellum is responsible for motor planning and preparedness, PAG and more rostral subcortical structures (thalamus) may be related with responses to emotionally arousing stimuli. As described previously, the results here corroborate the view that information towards activation of the PAG occurs as a function of threat proximity [29]. Interestingly, inverse contrasts against proximal threat resulted in clusters in the right multimodal parietal lobes of the brain, what could suggest top-down modulation of integrative brain areas.…”

Section: Discussionsupporting

confidence: 91%

Behavioral and neuroimaging responses induced by mental imagery of threatening scenarios

Shuhama

Rondinoni

Araújo

et al. 2016

Behavioural Brain Research

View full text Add to dashboard Cite

h i g h l i g h t s• Imaginary of imminent threat scenarios increased fMRI signal of the dorsal midbrain.• Activity in vmPFC was reduced during the imagination of imminent threat scenarios.• Activation pattern was consistent with animal data and actual threat situations.• Imminent and potential threats modulate brain structures related to fear and anxiety.• Mental imagery is a reliable method to study the neurobiology of behavioral processes. Functional neuroimaging studies have shown that actual situations of uncertain or distant threats increase the activity of forebrain regions, whereas proximal threats increase the activity of the dorsal midbrain. This experiment aimed at testing the hypothesis that brain activity elicited by imagined scenarios of threats with two different magnitudes, potential and imminent, resembles that found in response to actual threats. First, we measured subjective responses to imagined scenarios of potential and imminent threats compared with neutral and pleasant scenarios. The same scenarios were used as a paradigm in a functional magnetic resonance imaging experiment. Behavioral results show that the scenarios draw a gradient of hedonic valence and arousal dimensions. Both potential and imminent threat scenarios increased subjective anxiety; the imminent threat scenario also increased feelings of discomfort and bodily symptoms. The functional magnetic resonance imaging results revealed modulations of BOLD signal in the ventromedial prefrontal cortex by potential threat and in the periaqueductal gray matter by imminent threat. These results agree with previously reported evidence using actual threat situations, indicating that mental imagery is a reliable method for studying the functional neuroanatomy of relevant behavioral processes.

show abstract

Section: Discussionsupporting

confidence: 91%

Behavioral and neuroimaging responses induced by mental imagery of threatening scenarios

Shuhama

Rondinoni

Araújo

et al. 2016

Behavioural Brain Research

View full text Add to dashboard Cite

show abstract

“…Both patients and controls demonstrated increased amygdala activity for unpleasant versus pleasant images. Likewise, no difference between groups was observed in the PAG, a midbrain region crucial for the generation of defensive freezing (Bandler and Shipley, 1994;Brandão, et al, 2008;Hermans, et al, 2013;Satpute, et al, 2013) and implicated in emotion-modulated force control . These results do not support the hypothesis that these areas would be abnormally modulated in FND.…”

Section: Discussionmentioning

confidence: 81%

Aversive stimuli exacerbate defensive motor behaviour in motor conversion disorder

et al. 2016

View full text Add to dashboard Cite

A B S T R A C TConversion disorder or functional neurological symptom disorder (FND) can affect the voluntary motor system, without an organic cause. Functional symptoms are thought to be generated unconsciously, arising from underlying psychological stressors. However, attempts to demonstrate a direct relationship between the limbic system and disrupted motor function in FND are lacking. We tested whether negative affect would exacerbate alterations of motor control and corresponding brain activations in individuals with FND. Ten patients and ten healthy controls produced an isometric precision-grip contraction at 10% of maximum force while either viewing visual feedback of their force output, or unpleasant or pleasant emotional images (without feedback). Force magnitude was continuously recorded together with change in brain activity using fMRI. For controls, force output decayed from the target level while viewing pleasant and unpleasant images. Patients however, maintained force at the target level without decay while viewing unpleasant images, indicating a pronounced effect of negative affect on force output in FND. This emotional modulation of force control was associated with different brain activation patterns between groups. Contrasting the unpleasant with the pleasant condition, controls showed increased activity in the inferior frontal cortex and pre-supplementary motor area, whereas patients had greater activity in the cerebellum (vermis), posterior cingulate cortex, and hippocampus. Engagement of a cerebellar-limbic network in patients is consistent with heightened processing of emotional salience, and supports the role of the cerebellum in freezing responses in the presence of aversive events. These data highlight a possible neural circuit through which psychological stressors elicit defensive behaviour and modulate motor function in FND.

show abstract

“…Studies in rodents have demonstrated that this freezing behaviour and the associated increased parasympatethic tone depend on the amgydala to periacqueductal grey (PAG) projections [82]. A recent study in healthy volunteers [83] has also shown that the same neural circuits (i.e. amgydala-PAG connections) may be critically involved in humans as well to mediate fear bradycardia.…”

Section: Discussionmentioning

confidence: 99%

Globally conditioned Granger causality in brain–brain and brain–heart interactions: a combined heart rate variability/ultra-high-field (7 T) functional magnetic resonance imaging study

Duggento

Bianciardi

Passamonti

et al. 2016

Phil. Trans. R. Soc. A.

View full text Add to dashboard Cite

One contribution of 16 to a theme issue 'Uncovering brain-heart information through advanced signal and image processing' . Subject Areas: medical physics, computational biology Keywords:Granger causality, brain-heart interactions, blood-oxygen-level dependent, heart rate variability, ultra-high-field functional magnetic resonance imaging Globally conditioned Granger causality in brain-brain and brain-heart interactions: a combined heart rate variability/ultra-high-field (7 T) functional magnetic resonance imaging study The causal, directed interactions between brain regions at rest (brain-brain networks) and between resting-state brain activity and autonomic nervous system (ANS) outflow (brain-heart links) have not been completely elucidated. We collected 7 T resting-state functional magnetic resonance imaging (fMRI) data with simultaneous respiration and heartbeat recordings in nine healthy volunteers 2016 The Author(s) Published by the Royal Society. All rights reserved. to investigate (i) the causal interactions between cortical and subcortical brain regions at rest and (ii) the causal interactions between resting-state brain activity and the ANS as quantified through a probabilistic, point-process-based heartbeat model which generates dynamical estimates for sympathetic and parasympathetic activity as well as sympathovagal balance. Given the high amount of information shared between brain-derived signals, we compared the results of traditional bivariate Granger causality (GC) with a globally conditioned approach which evaluated the additional influence of each brain region on the causal target while factoring out effects concomitantly mediated by other brain regions. The bivariate approach resulted in a large number of possibly spurious causal brain-brain links, while, using the globally conditioned approach, we demonstrated the existence of significant selective causal links between cortical/subcortical brain regions and sympathetic and parasympathetic modulation as well as sympathovagal balance. In particular, we demonstrated a causal role of the amygdala, hypothalamus, brainstem and, among others, medial, middle and superior frontal gyri, superior temporal pole, paracentral lobule and cerebellar regions in modulating the so-called central autonomic network (CAN). In summary, we show that, provided proper conditioning is employed to eliminate spurious causalities, ultra-high-field functional imaging coupled with physiological signal acquisition and GC analysis is able to quantify directed brain-brain and brain-heart interactions reflecting central modulation of ANS outflow.

show abstract

Fear bradycardia and activation of the human periaqueductal grey

Cited by 113 publications

References 71 publications

Behavioral and neuroimaging responses induced by mental imagery of threatening scenarios

Behavioral and neuroimaging responses induced by mental imagery of threatening scenarios

Aversive stimuli exacerbate defensive motor behaviour in motor conversion disorder

Globally conditioned Granger causality in brain–brain and brain–heart interactions: a combined heart rate variability/ultra-high-field (7 T) functional magnetic resonance imaging study

Contact Info

Product

Resources

About