Neural dynamics of shooting decisions and the switch from freeze to fight

Real-life shooting decisions typically occur under acute threat and require fast switching between vigilant situational assessment and immediate fight-or-flight actions. Recent studies suggested that freezing facilitates action preparation and decision-making but the neurocognitive mechanisms remain unclear. We applied functional magnetic resonance imaging, posturographic and autonomic measurements while participants performed a shooting task under threat of shock. two independent studies, in unselected civilians (N = 22) and police recruits (N = 54), revealed that preparation for shooting decisions under threat is associated with postural freezing, bradycardia, midbrain activity (including the periaqueductal gray-PAG) and PAG-amygdala connectivity. Crucially, stronger activity in the midbrain/pAG during this preparatory stage of freezing predicted faster subsequent accurate shooting. Finally, the switch from preparation to active shooting was associated with tachycardia, perigenual anterior cingulate cortex (pgACC) activity and pgACC-amygdala connectivity. These findings suggest that threat-anticipatory midbrain activity centred around the PAG supports decision-making by facilitating action preparation and highlight the role of the pgACC when switching from preparation to action. These results translate animal models of the neural switch from freeze-to-action. In addition, they reveal a core neural circuit for shooting performance under threat and provide empirical evidence for the role of defensive reactions such as freezing in subsequent action decision-making

Anticipatory versus Reactive Spatial Attentional Bias to Threat

This is the peer reviewed version of the following article: Gladwin, T.E., Mobius, M., McLoughlin, S., & Tyndall, I. (2019). Anticipatory versus reactive spatial attentional bias to threat. British Journal of Psychology 110(1) pp. 3-14, which has been published in final form at https://doi.org/10.1111/bjop.12309 This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-ArchivingDot-probe or visual probe tasks (VPTs) are used extensively to measure attentional biases. A novel variant termed the cued VPT (cVPT) was developed to focus on the anticipatory component of attentional bias. This study aimed to establish an anticipatory attentional bias to threat using the cVPT and compare its split-half reliability with a typical dot-probe task. A total of 120 students performed the cVPT task and dot-probe tasks. Essentially, the cVPT uses cues that predict the location of pictorial threatening stimuli, but on trials on which probe stimuli are presented the pictures do not appear. Hence, actual presentation of emotional stimuli did not affect responses. The reliability of the cVPT was higher at most cue–stimulus intervals and was .56 overall. A clear anticipatory attentional bias was found. In conclusion, the cVPT may be of methodological and theoretical interest. Using visually neutral predictive cues may remove sources of noise that negatively impact reliability. Predictive cues are able to bias response selection, suggesting a role of predicted outcomes in automatic processes

Afferent cardiac signals modulate attentional engagement to low spatial frequency fearful faces

Despite the growing consensus that the continuous dynamic cortical representations of internal bodily states shape the subjective experience of emotions, physiological arousal is typically considered only a consequence and rarely a determinant of the emotional experience. Recent experimental approaches study how afferent autonomic signals from the heart modulate the processing of sensory information by focussing on the phasic properties of arterial baroreceptor firing that is active during cardiac systole and quiescent during cardiac diastole. For example, baroreceptor activation has been shown to enhance the processing of threat-signalling stimuli. Here, we investigate the role of cardiac afferent signals in the rapid engagement and disengagement of attention to fear stimuli. In an adapted version of the emotional attentional cueing paradigm, we timed the presentation of cues, either fearful or neutral faces, to coincide with the different phases of the cardiac cycle. Moreover, we presented cues with different spatial frequency ranges to investigate how these interoceptive signals influence the processing of visual information. Results revealed a selective enhancement of attentional engagement to low spatial frequency fearful faces presented during cardiac systole relative to diastole. No cardiac cycle effects were observed to high spatial frequency nor broad spatial frequency cues. These findings expand our mechanistic understanding of how body–brain interactions may impact the visual processing of fearful stimuli and contribute to the increased attentional capture of threat signals

Freeze to see: The effect of threat on detection of coarse visual features

Contains fulltext : 201410.pdf (publisher's version ) (Open Access)Radboud University, 28 februari 2019Promotor : Roelofs, K. Co-promotor : Hermans, E.J.127 p

Wind Speed Modeling

Applied mathematicsElectrical Engineering, Mathematics and Computer Scienc

Unconscious processing of coarse visual information during anticipatory threat

Contains fulltext : 201448pub.pdf (publisher's version ) (Closed access)Rapid detection of threats has been proposed to rely on automatic processing of their coarse visual features. However, it remains unclear whether such a mechanism is restricted to detection of threat cues, or whether it reflects a broader sensitivity to even neutral coarse visual information features during states of threat. We used a backward masking task in which participants discriminated the orientation of subliminally presented low (3 cpd) and high (6 cpd) spatial frequency gratings, under threat (of shock) and safe conditions. Visual awareness of the gratings was assessed objectively using an additional localization task. When participants were unaware of the gratings, above chance and improved discrimination of low-spatial frequency gratings was observed under threat compared to safe trials. These findings demonstrate unconscious processing of neutral coarse visual information during threat state, supporting the view that automatic threat detection may rely on a general facilitation of coarse features irrespective of threat content.7 p

Freezing promotes perception of coarse visual features

Item does not contain fulltextFreezing is an evolutionarily preserved defensive behavior, characterized by immobility and heart rate deceleration, which is thought to promote visual perception. Rapid perceptual assessment of threat is crucial in life-threatening situations; for example, when policemen need to make split-second decisions about the use of deadly force. Here, we hypothesized that freezing is specifically associated with better perception of rapidly processed coarse, low-spatial frequency (LSF) features. We used a visual discrimination task in which participants determined the orientation of LSF and high-spatial frequency (HSF) gratings under threat of shock and safe conditions. As predicted, threat anticipation improved perception of LSF at the expense of HSF gratings. Crucially, stronger decrease in heart rate, a parasympathetic physiological index of freezing, was linked to better perception of LSF. These results provide empirical evidence for the comobilization of physiological and perceptual processes, which may play an important role in decision making under acute stress. (PsycINFO Database Record9 p