Understanding of the mechanisms underlying cognitive flexibility is a subject of current research. It remains an elusive property of distributed brain function that instantiates itself in many ways. Human studies using
functional magnetic resonance imaging (fMRI) and animal studies using
optogenetics have shown that cognitive flexibility relies on a variety of distinct regions of the brain that work in concert, including the
prefrontal cortex (PFC),
anterior cingulate cortex (ACC),
posterior parietal cortex (PPC),
basal ganglia, and
thalamus. The regions active during engagement of cognitive flexibility depend on the task and various factors involved in flexibility that are used to assess the behavior, as flexible thinking requires aspects of inhibition, attention, working memory, response selection, and goal maintenance. Another study further extended these results by demonstrating that the level of abstractness of the switch type influenced recruitment of differing regions in the PFC depending on whether the participant was asked to make a cognitive set switch, a response switch, or a stimulus or perceptual switch. A set switch would require switching between task rules, as with the WCST, and is considered to be the most abstract. A response switch would require different response mapping, such as circle right button and square left button and vice versa. Lastly, a stimulus or perceptual set switch would require a simple switch between a circle and a square. Activation is mediated by the level of abstractness of the set switch in an anterior to posterior fashion within the PFC, with the most anterior activations elicited by set switches and the most posterior activations resulting from stimulus or perceptual switches. Network energy analysis revealed that the frontoparietal and dorsal attention networks primarily operate efficiently during cognitive flexibility, while the salience network and subcortical structures exhibit moderate levels of efficiency in supporting this function. Task-based functional magnetic resonance imaging (fMRI) studies have provided detailed insights into the key brain regions involved in cognitive flexibility, including the inferior frontal junction and areas within the midcingulo-insular network, such as the insular cortex and dorsal anterior cingulate cortex, emphasizing their critical role in adapting to changing task demands.
Development Children can be strikingly inflexible when assessed using traditional tests of cognitive flexibility, but this does not come as a surprise considering the many cognitive processes involved in the mental flexibility, and the various developmental trajectories of such abilities. With age, children generally show increases in cognitive flexibility which is likely a product of the protracted development of the
frontoparietal network evident in adults, with maturing
synaptic connections, increased
myelination and regional
gray matter volume occurring from birth to mid-twenties.
Deficits Diminished cognitive flexibility has been noted in a variety of neuropsychiatric disorders such as
anorexia nervosa,
obsessive–compulsive disorder,
schizophrenia,
autism, and in a subset of people with
ADHD. Each of these disorders exhibit varying aspects of cognitive inflexibility. For example, those with obsessive–compulsive disorder experience difficulty shifting their attentional focus as well as inhibiting motor responses. Children with autism show a slightly different profile with deficits in adjusting to changing task contingencies, while often maintaining the ability to respond in the face of competing responses. Potential treatments may lie in neurochemical modulation. Juveniles with
anorexia nervosa have marked decreases in set-shifting abilities, possibly associated with incomplete maturation of prefrontal cortices associated with malnutrition. One can also consider people with addictions to be limited in cognitive flexibility, in that they are unable to flexibly respond to stimuli previously associated with the drug.
Aging The elderly often experience deficits in cognitive flexibility. The aging brain undergoes physical and functional changes including a decline in processing speed, central sensory functioning,
white matter integrity, and brain volume. Regions associated with cognitive flexibility such as the PFC and PC atrophy, or shrink, with age, but also show greater task-related activation in older individuals when compared to younger individuals. This increase in blood flow is potentially related to the evidence that atrophy heightens blood flow and metabolism, which is measured as the BOLD response, or blood-oxygen-level dependence, with fMRI. Studies suggest that aerobic exercise and training can have
plasticity inducing effects that could potentially serve as an intervention in old age that combat the decline in executive function. ==Implications for education and general learning==