Nuclear disconnection within the amygdala reveals a direct pathway to fear.
It is widely believed that a descending serial circuit consisting of neural projections from the basolateral complex (BLA) to the central nucleus (CEA) of the amygdala mediates fear expression. Here we directly test this hypothesis and show that disconnecting the BLA and CEA with asymmetric neurotoxic lesions after Pavlovian fear conditioning in rats completely abolishes the expression of conditional freezing. These results demonstrate that neural projections from the BLA to CEA are essential for the expression of learned fear responses.
Jimenez
Stephanie A
SA
Neuroscience Program, University of Michigan, Ann Arbor, Michigan 48109-1043, USA.
Maren
Stephen
S
D000161:Acoustic Stimulation / Q000009:adverse effects; D000679:Amygdala / Q000033:anatomy & histology / Q000293:injuries / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D001362:Avoidance Learning / Q000187:drug effects; D001522:Behavior, Animal / Q000502:physiology; D003214:Conditioning, Classical / Q000502:physiology*; D004597:Electroshock / Q000009:adverse effects; D018690:Excitatory Amino Acid Agonists / Q000633:toxicity; D005239:Fear / Q000502:physiology*; D046352:Freezing Reaction, Cataleptic / Q000187:drug effects / Q000502:physiology; D007839:Functional Laterality; D005786:Gene Expression Regulation / Q000187:drug effects; D008297:Male; D016202:N-Methylaspartate / Q000633:toxicity; D009415:Nerve Net / Q000187:drug effects / Q000293:injuries / Q000502:physiology*; D016760:Proto-Oncogene Proteins c-fos / Q000378:metabolism; D051381:Rats; D020318:Rats, Long-Evans; D016622:Silver Staining
D018690:Excitatory Amino Acid Agonists; D016760:Proto-Oncogene Proteins c-fos; D016202:N-Methylaspartate