Basolateral Amygdala Circuits for Fear Depend on Context
Joanna Yau, Amy Li, Lauren Abdallah, Leszek Lisowski, and Gavan McNally
(see article e0857242024)
In this issue, neuroscientists continue to illuminate the context dependence of circuit activation. Yau et al. investigated appetitive and aversive basolateral amygdala (BLA) circuits using photometry recordings in rats. Rats learned to associate a sound with a footshock in two contexts: a neutral environment or an environment in which they could lever press for a food reward. The authors explored the roles of either central amygdala (CeA)- or nucleus accumbens (NAc)-projecting neurons from the BLA in reward and aversion using these contexts. The BLA→CeA circuit was engaged in footshock conditions regardless of the context and inhibiting the circuit suppressed fear responses. BLA→NAc was recruited only in the reward context and inhibiting this circuit enhanced fear responses only in the reward context. Altogether, this study reveals circuit- and state-dependent BLA processing of fear and is informative for treatment development in those who suffer from trauma.
Overlay of retrogradely labeled neurons and three different gene expression profiles in the rat BLA. This technique helped characterize BLA output pathways. See Yau et al. for more information.
A Brain Region for Evaluating the Value of Cognitive Effort
Jennifer Crawford, Rachel Brough, Sarah Eisenstein, Jonathan Peelle, and Todd Braver
(see article e0367242024)
How do we decide whether to exert cognitive effort? This is what Crawford et al. set out to answer. Participants in their study performed in a Cognitive Effort Discounting Paradigm as the authors imaged their brains with functional magnetic resonance imaging (fMRI) to assess what brain regions evaluate cognitive effort demands relative to reward outcomes. Two cognitive domains were measured: working memory and speech comprehension. The authors found that the dorsal anterior cingulate cortex (dACC) played a significant role in cognitive effort decisions: it tracked the relative subjective value of a low-effort, low-reward option and had the strongest activity when this was of greater value than the high-effort, high-reward option. In other words, the dACC seems to signal differences in choice option values. Notably, activity in the dACC could predict subsequent choice behavior in both working memory and speech comprehension domains. These findings suggest that the dACC could be a treatment target in those who are unable to make incentive- and effort-based decisions due to high levels of apathy.
Footnotes
This Week in The Journal was written by Paige McKeon
