Neural activity associated with monitoring the oscillating threat value of a tarantula

• DOI: 10.1073/pnas.1009076107
• Publication Date: 2010-11-09T07:04:38Z
• Authors: Dean Mobbs; Rongjun Yu; James B. Rowe; Hannah Eich; Oriel FeldmanHall; Tim Dalgleish
• Keywords: Orbitofrontal cortex; Periaqueductal gray; Phobias

Phylogenetic threats such as spiders evoke our deepest primitive fears. When close or looming, engage evolutionarily conserved monitoring systems and defense reactions that promote self-preservation. With the use of a modified behavioral approach task within functional MRI, we show that, tarantula was placed closer to subject's foot, increased experiences fear coincided with augmented activity in cascade fear-related brain networks including periaqueductal gray, amygdala, bed nucleus stria terminalis. Activity amygdala also associated underprediction tarantula's threat value and, addition terminalis, indexed by its direction movement. Conversely, orbitofrontal cortex engaged grew more distant, suggesting this region emits safety signals expels fear. Our findings fractionate neurobiological mechanisms basic potentially illuminate perturbed characterize clinical phobias.