Right-sided human prefrontal brain activation during acquisition of conditioned fear.

• This H2(15)O positron emission tomography (PET) study reports on relative regional cerebral blood flow (rCBF) alterations during fear conditioning in humans. In the PET scanner, subjects viewed a TV screen with either visual white noise or snake videotapes displayed alone, then with electric shocks, followed by final presentations of white noise and snakes. Autonomic nervous system responses confirmed fear conditioning only to snakes. To reveal neural activation during acquisition, while equating sensory stimulation, scans during snakes with shocks and white noise alone were contrasted against white noise with shocks and snakes alone. During acquisition, rCBF increased in the right medial frontal gyrus, supporting a role for the prefrontal cortex in fear conditioning to unmasked evolutionary fear-relevant stimuli.

Keyword

Adult

Animals

Arousal/physiology

Brain Mapping

Conditioning; Classical/*physiology

Dominance; Cerebral/*physiology

Evolution

Fear/*physiology

Female

Humans

Prefrontal Cortex/*physiology/radionuclide imaging

Regional Blood Flow/physiology

Research Support; Non-U.S. Gov't

Snakes

Tomography; Emission-Computed

Publication and Content Type

ref (subject category)

art (subject category)