Fear extinction requires infralimbic cortex projections to the basolateral amygdala

PL (Prelimbic area) MBA:972 projects to BLA (Basolateral amygdalar nucleus) MBA:295 · Mouse

Retrograde CTB deposited in the BLA labelled neurons in the prelimbic cortex as well as the IL, and fluorescent retrobeads injected into the BLA labelled PL pyramidal neurons that were subsequently patched, showing a PL source of BLA-projecting axons.

Fig. 1c–d; Fig. 2a,h–k; Results, 'Separate IL and PL projections to BLA and NAc'

Made by an AI model reading the paper (claude-opus-5, extract@0.3.0); a second AI model (claude-opus-5) agrees.

PL (Prelimbic area) MBA:972 projects to ACB (Nucleus accumbens) MBA:56 · Mouse

Retrograde CTB in the nucleus accumbens labelled prelimbic cortex neurons in addition to IL neurons, and retrobeads placed in the NAc allowed recordings from identified PL-NAc projection neurons.

Fig. 1c–d; Fig. 3a,h–k; Results, 'Separate IL and PL projections to BLA and NAc'

Made by an AI model reading the paper (claude-opus-5, extract@0.3.0); a second AI model (claude-opus-5) agrees.

ILA (Infralimbic area) MBA:44 projects to ACB (Nucleus accumbens) MBA:56 · Mouse

CTB injected into the nucleus accumbens retrogradely labelled a dense population of infralimbic neurons (58.4% of all labelled PFC cells were NAc-labelled), largely separate from the BLA-projecting population; retrobeads in the NAc similarly identified IL projection neurons for recording.

Fig. 1a–d; Fig. 3a; Results, 'Separate IL and PL projections to BLA and NAc'

Made by an AI model reading the paper (claude-opus-5, extract@0.3.0); a second AI model (claude-opus-5) agrees.

ILA (Infralimbic area) MBA:44 projects to BLA (Basolateral amygdalar nucleus) MBA:295 · Mouse

Cholera toxin B injected into the BLA retrogradely labelled many neurons in the infralimbic cortex, in both layer 2/3 and layer 5, with labelling described as dense and concentrated in superficial IL layers; of all labelled PFC cells, 38.2% were BLA-labelled and only 3.4% were double-labelled with NAc tracer. Retrobeads and a retrograde HSV-Cre placed in the BLA likewise labelled IL neurons that were then recorded or chemogenetically targeted.

Fig. 1a–d; Fig. 2a; Fig. 4a–b; Results, 'Separate IL and PL projections to BLA and NAc'

Made by an AI model reading the paper (claude-opus-5, extract@0.3.0); a second AI model (claude-opus-5) agrees.