Nucleus accumbens neurons dynamically respond to appetitive and aversive associative learning

We examined the involvement of nucleus accumbens' D1-  and D2-neurons in associative learning, by measuring calcium transients with fiber photometry in mice. We show that during appetitive Pavlovian learning, D1- and D2-neurons exhibit a general increase in activity in response to the conditioned stimuli (CS), and distinct changes in activity after un conditioned stimulus (US – sucrose) consumption that dynamically evolve throughout learning. In an aversive Pavlovian learning task, D1- and D2-neurons develop increases in activity in response to both CS and US (shock). Our data support a model of concurrent activation of D1- and D2-neurons durin g appetitive and aversive conditioning. AbstractTo survive, individuals must learn to associate cues in the environment with emotionally relevant outcomes. This association is partially mediated by the nucleus accumbens (NAc), a key brain region of the reward circuit that is mainly composed by GABAergic medium spiny neurons (MSNs), that express either dopamine receptor D1 or D2. Recent studies showed that both populations can drive reward and aversion, however, the activity of these neurons during appetitive and aversive Pavlovian conditioning remains to be determined. Here, we investigated the relevance of D1- and D2-neurons in associative learning, by measuring calcium transients with fiber photometry during appetitive and aversive Pavlovian tasks in mice. Sucrose was used as a positive valence unconditioned stimulus (US) and foot...
Source: Journal of Neurochemistry - Category: Neuroscience Authors: Tags: ORIGINAL ARTICLE Source Type: research