Distinct effects of prefrontal and parietal cortex inactivations on an accumulation of evidence task in the rat

• Published in: eLife Vol. 4
• Main Authors: Erlich, Jeffrey C, Brunton, Bingni W, Duan, Chunyu A, Hanks, Timothy D, Brody, Carlos D
• Format: Journal Article
• Language: English
• Published: England eLife Sciences Publications Ltd 14.04.2015; eLife Sciences Publications, Ltd
• Subjects: accumulation; Animals; Behavior, Animal; Bias; Brain; Brain Mapping; Choice Behavior; Clinical decision making; Cortex (parietal); Decision making; inactivation; Male; Memory; modeling; Models, Neurological; Monkeys & apes; Neuroscience; Parietal Lobe - physiology; Prefrontal cortex; Prefrontal Cortex - physiology; Rats, Long-Evans; Short term; Task Performance and Analysis; modeling; rat; accumulation; decision-making; neuroscience; inactivation
• ISSN: 2050-084X; 2050-084X
• DOI: 10.7554/elife.05457

Numerous brain regions have been shown to have neural correlates of gradually accumulating evidence for decision-making, but the causal roles of these regions in decisions driven by accumulation of evidence have yet to be determined. Here, in rats performing an auditory evidence accumulation task, we inactivated the frontal orienting fields (FOF) and posterior parietal cortex (PPC), two rat cortical regions that have neural correlates of accumulating evidence and that have been proposed as central to decision-making. We used a detailed model of the decision process to analyze the effect of inactivations. Inactivation of the FOF induced substantial performance impairments that were quantitatively best described as an impairment in the output pathway of an evidence accumulator with a long integration time constant (>240 ms). In contrast, we found a minimal role for PPC in decisions guided by accumulating auditory evidence, even while finding a strong role for PPC in internally-guided decisions.