Dopamine's Role in Fear Extinction

• Key Finding: A study by MIT neuroscientists shows that dopamine release in a specific brain circuit signals when a fear can be forgotten.
• Mechanism: Dopamine sent from the ventral tegmental area (VTA) activates specific neurons (Ppp1r1b) in the posterior basolateral amygdala (pBLA).
• Function: This activation drives fear extinction learning, essentially teaching the brain that a previously perceived danger is no longer present.
• Contrast: Different VTA neurons send dopamine to anterior BLA (aBLA) neurons (Rspo2) to encode the initial fear memory.
• Significance: This discovery identifies a critical mechanism for regulating fear and offers potential targets for treating anxiety disorders like PTSD.