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Under threat, computations underlying value-based decision-making shift from being driven by predominantly value-related regions – such as the ventromedial cortex (vmPFC) and striatum – to being driven by brain regions involved in threat coping – such as the (dorsal) anterior cingulate cortex and amygdala (ACC, AMY) (Park, Kahnt, Rieskamp, & Heekeren, 2011; Roy et al., 2014). Simultaneously, the presence of environmental threat triggers a defensive state of freezing which is primarily characterized by heart rate deceleration (bradycardia) and body immobility, and is thought to be driven by activation in the brain stem periaqueductal gray (PAG; (Kozlowska, Walker, McLean, & Carrive, 2015)). The state associated with freezing has been associated with improved perception of course visual features, faster responding, and has been implicated to play a role in risk assessment (Blanchard, Griebel, Pobbe, & Blanchard, 2011; Hashemi et al., 2019; Lojowska, Gladwin, Hermans, & Roelofs, 2015). Together, this suggests an important role for freezing in decision-making under threat, potentially affecting the decision whether to approach or avoid the situation. However, it remains unclear how freezing would affect the neural computations underlying such value-based approach-avoidance decision-making. In this study, we test three potential pathways through which this could manifest (Livermore et al., 2021). First, it could be that freezing moderates the subjective value of aversive outcome information (Roy et al., 2014). Secondly, freezing could feed into the integration of reward and punishment values (Park et al., 2011). Finally, freezing could be involved in the tendency to respond passively vs. actively, moderating activity in regions involved in switching into action and action preparation (Hashemi et al., 2019). In this study, we will investigate how freezing under threat – assessed through bradycardia – is linked to neural activity in brain regions involved in passive and active approach-avoidance decision-making under threat.