Behavioral flexibility is associated with changes in structure and function distributed across a frontal cortical network in macaques

• DOI: 10.1371/journal.pbio.3000605
• Publication Date: 2020-05-26T17:39:19Z
• Authors: Jérôme Sallet; MaryAnn P. Noonan; Adam Thomas; Jill X. O’Reilly; Jesper Anderson; Georgios K. Papag...; Franz X. Neubert; Bashir Ahmed; Jackson Smith; Andrew H. Bell; Mark J. Buckley; Léa Roumazeilles; Steven Cuell; Mark E. Walton; Kristine Krug; Rogier B. Mars; Matthew F. S. Rus...
• Keywords: Orbitofrontal cortex; Frontal lobe; Cingulate cortex; Brain mapping

One of the most influential accounts central orbitofrontal cortex—that it mediates behavioral flexibility—has been challenged by finding that discrimination reversal in macaques, classic test flexibility, is unaffected when lesions are made excitotoxin injection rather than aspiration. This suggests critical brain circuit mediating flexibility tasks lies beyond cortex. To determine its identity, a group nine macaques were taught learning tasks, and impact on gray matter was measured. Magnetic resonance imaging scans taken before after compared with from two control groups, each comprising 10 animals. learned similar but lacked any component, other engaged no learning. Gray changes prominent posterior cortex/anterior insula also found three frontal cortical regions: lateral cortex (orbital part area 12 [12o]), cingulate cortex, prefrontal In second analysis, neural activity measured at rest, pattern coupling regions assessed. Activity increased significantly comparison controls. final set experiments, we used structural procedures analyses to demonstrate aspiration lesion type known affect learning, affected structure same circuit. The results identify distributed associated flexibility.