Task-switching abilities in episodic and chronic migraine.

Migraineurs show impaired cognitive functions interictally, mainly involving information processing speed, basic attention, and executive functions. We aimed to assess executive impairment in migraine patients with different attack frequencies through a task-switching protocol designed to assess different sub-processes of executive functioning. We enrolled 42 migraine patients and divided them into three groups based on the attack frequency: 13 subjects had episodic migraine with a low frequency (LFEM, 4-7 migraine days per month), 14 subjects had high-frequency episodic migraine (HFEM, 8-14 days) and, finally, 15 subjects presented chronic migraine (≥ 15 headache days/month, CM); we compared them to 20 healthy control (HC), matched to both gender and education. Patients with high headache frequencies (CM and HFEM) showed worse performance than LFEM and HC controls, as indicated by poor accuracy, increased switch cost, and reaction times. Our study demonstrated a difference in task-switching abilities in patients with high frequency or chronic migraine compared with low-frequency episodic migraine and healthy controls. These difficulties in executive control processes could be related to altered functioning of the frontal cortex and its cortical and subcortical connections.