Survival circuits and risk assessment

Risk assessment (RA) behaviour is unusual in the context of survival circuits. An external object elicits eating, mating or fleeing; but conflict between internal approach and withdrawal tendencies elicits RA-specific behaviour that scans the environment for new information to bring closure. Recently rodent and human threat responses have been compared using 'predators' that can be real (e.g. a tarantula), robot, virtual, or symbolic (with the last three rendered predatory by the use of shock). 'Quick and dirty' survival circuits in the periaqueductal grey, hypothalamus, and amygdala control external RA behaviour. These subcortical circuits activate, and are partially inhibited by, higher-order internal RA processes (anxiety, memory scanning, evaluation and sometimes - maladaptive rumination) in the ventral hippocampus and medial prefrontal cortex.