2021-12-08The balance between OFC and NAc is critical for negative occasion setting learning

Imbalanced Activity in the Orbitofrontal Cortex and Nucleus Accumbens Impairs Behavioral Inhibition

Heidi C. Meyer and David J. Bucci

Current Biology (2016)

doi: 10.1016/j.cub.2016.08.034

The conceptual gap or the scientific question: is the imblanced activity between orbitofrontal cortex and nucleus accumbens crucial for negative occasion setting learning?

How the authors proposed the question: two points drive this study: 1. an observation of imblanced activity of orbitofrontal cortex (OFC) and nucleus accumbens (NAc) during adolescence; 2. an well established behavioral paradigm (negative occasion setting) at hand. The link is adolescence has more impulsive behaviors, which is exemplified by the failure in behavioral inhibition. This process involves inhibitory learning, which can be well modeled with negative occasion setting behavioral paradigm. It s hard to tell whether they first developed this task or first had the observations in mind. 

Brief summary: by training rats to learn a negative occasion setting task (a light indicates no reward of an otherwise reward-predicting conditioned auditory cue), the authors shown that simultaneously inactivating the OFC with hM4D and activating the NAc with hM3D impaired the inhibitory learning of negative occasion setting task. The impairment was much more severe than the manipulation of either one alone, indicating that the balanced activity between them is crucial for inhibitory learning.

How the authors tell the story: it s the balance, but not only the activity of either single brain area, critical for inhibitory learning. I like this idea. It instantiates a new thinking style, at least for me, to inquire the brain functions. 

The ongoing question(s) inspired by the current study: it s really fascinating to know the spiking activity of these two brain areas during the learning and performance of this task.