Left medial orbitofrontal cortex volume correlates with skydive-elicited euphoric experience

Area of Science:

• Neuroscience
• Affective Science
• Neuroimaging

Background:

• The medial orbitofrontal cortex (mOFC) is implicated in positive affect.
• Individual differences in mOFC volume are linked to variations in positive affect expression.
• The neural basis of euphoria, an extreme form of positive affect, remains poorly understood.

Purpose of the Study:

• To investigate the relationship between medial orbitofrontal cortex (mOFC) structure and the experience of euphoria.
• To test the hypothesis that mOFC volume predicts individual differences in euphoric intensity.

Main Methods:

• Structural magnetic resonance imaging (MRI) was used to measure orbitofrontal cortical volumes in 31 participants.
• Self-reported euphoria levels were assessed in response to a novel, high-arousal experience (first-time skydive).

Main Results:

• Skydiving induced significant increases in self-reported euphoria.
• Left mOFC volume positively predicted the intensity of participants' euphoric experience.
• Both left mOFC and the amygdalo-hippocampal complex independently accounted for variance in euphoria.

Conclusions:

• Medial orbitofrontal cortex (mOFC) volume is a significant predictor of individual differences in euphoria.
• The mOFC, as part of a broader corticolimbic circuit, plays a crucial role in the neural basis of extreme positive emotional experiences.