Both the learning of an aversive CS-US pairing in classical fear conditioning and the extinction of a fear response critically rely on the amygdala to occur. Additionally, several lines of evidence suggest that extinction learning is not simply an erasure of the original fear memory, but a distinct and parallel form of learning that suppresses the expression of the conditioned fear response. Thus there appear to be two forms of learning that occur in the basolateral amygdala which have opposing effects on the expression of conditioned fear through the output of the amygdala (the central nucleus). We hypothesize that these two forms of learning will produce differential patterns of second-messenger and transcription factor activation within the sub-populations of excitatory and inhibitory neurons that constitute the associative learning circuit in the basolateral complex of the amygdala (BLA). Furthermore, we hypothesize that by using pharmacologic and genetic manipulations targeting one particular sub-population of BLA neurons, we may be able to selectively alter one of these two types of learning while leaving the other intact.
|Chhatwal, Jasmeer P; Gutman, Alisa R; Maguschak, Kimberly A et al. (2009) Functional interactions between endocannabinoid and CCK neurotransmitter systems may be critical for extinction learning. Neuropsychopharmacology 34:509-21|
|Almonte, Antoine G; Hamill, Cecily E; Chhatwal, Jasmeer P et al. (2007) Learning and memory deficits in mice lacking protease activated receptor-1. Neurobiol Learn Mem 88:295-304|
|Chhatwal, J P; Hammack, S E; Jasnow, A M et al. (2007) Identification of cell-type-specific promoters within the brain using lentiviral vectors. Gene Ther 14:575-83|
|Heldt, S A; Stanek, L; Chhatwal, J P et al. (2007) Hippocampus-specific deletion of BDNF in adult mice impairs spatial memory and extinction of aversive memories. Mol Psychiatry 12:656-70|
|Chhatwal, Jasmeer P; Ressler, Kerry J (2007) Modulation of fear and anxiety by the endogenous cannabinoid system. CNS Spectr 12:211-20|
|Chhatwal, Jasmeer P; Davis, Michael; Maguschak, Kimberly A et al. (2005) Enhancing cannabinoid neurotransmission augments the extinction of conditioned fear. Neuropsychopharmacology 30:516-24|
|Chhatwal, Jasmeer P; Myers, Karyn M; Ressler, Kerry J et al. (2005) Regulation of gephyrin and GABAA receptor binding within the amygdala after fear acquisition and extinction. J Neurosci 25:502-6|