Uncertainty-Dependent Extinction of Fear Memory in an Amygdala-mPFC Neural Circuit Model
Fig 4
Shock procedure in the extended model.
(A, B) CS and US schedules; after extinction training of the partially reinforced fear memory, an additional CS-US pairing was applied, with the US being three times stronger (A) or the same intensity (B). (C, D) The blue, green, red and black lines indicate the activities of the LA (persistent neurons), vmPFC (extinction neurons), ITC (another group of extinction neurons) and CEA (fear neurons), respectively. (E, F) The blue, green, red and black lines indicate the learning signals that changed the weights of CS-related synaptic input to the LA, vmPFC, ITC and CEA, respectively. Note that overlapped lines were changed to dashed lines to make them visible. (G) Final activity levels of the CEA (fear neural unit) after re-extinction training were plotted depending on the US intensity.