An animal's ability to adjust its behavior flexibly in response to changing conditions is increasingly recognized as a key indicator of positive welfare and cognitive health, with reduced flexibility signaling chronic stress.
Chronic stress impairs the prefrontal cortex regions responsible for executive function and behavioral flexibility in mammals. An animal that cannot flexibly adapt to its environment - instead repeating stereotypic behaviors - is demonstrating neurological changes consistent with poor welfare. This insight has practical applications: monitoring behavioral repertoire breadth and flexibility in farmed and captive animals provides early warning of welfare deterioration before more obvious physical symptoms appear. Enrichment programs that restore behavioral flexibility serve as both treatment and prevention for chronic stress states.