FIGURE 8.5 Fear Circuits in the Brain When you’re faced with a potentially threatening stimulus—like a snake dangling from a stick—information arrives in the thalamus and is relayed simultaneously along two pathways. Crude, archetypal information rapidly travels the direct route to the amygdala, triggering an almost instantaneous fear response. More detailed information is sent along the pathway to the visual cortex, where the stimulus is interpreted. If the cortex determines that a threat exists, the information is relayed to the amygdala along the longer, slower pathway. The amygdala triggers other brain structures, such as the hypothalamus, which activate the sympathetic nervous system and the endocrine system’s release of stress hormones.

Source: Research from LeDoux (1994a, b).