Patients With Migraine Have Impaired Time Perception The study was published online July 23 in the journal Headache.
Migraineurs in the study tended to overestimate the duration of a visual stimulus when it was reported in milliseconds but not seconds, and although the neural mechanism underlying this impairment is not fully understood, it is suspected that the cerebellum is involved.
“We suggest that functional impairment in the cerebellum of migraineurs leads to the impairment of time perception specifically in milliseconds,” the authors, led by Juanjuan Zhang, MM, from the Anhui Medical University, Hefei, China, conclude. Better imaging methods are needed to study the activation of brain areas involved in time perception processing, they say.
The study included 27 patients (20 women and 7 men; mean age, 33.6 years) with migraine with and without aura from the outpatient department of the First Affiliated Hospital of Anhui Medical University. Their mean Mini-Mental State Examination (MMSE) score was 29.30 and mean intelligence quotient (IQ) was 103.67.
The study also included 27 healthy controls (21 women and 6 men) with a mean age of 31.96 years, mean MMSE of 29.52, and mean IQ of 106.56, who matched the migraineurs on demographic characteristics such as age, gender, and education level.
Patients and controls were asked to estimate the time in which a series of visual stimuli was delivered at different intervals over a range of milliseconds and seconds. Twenty visual stimuli were presented for each of the 3 durations (600 milliseconds, 3 seconds, 5 seconds), for a total of 60 trials in each run. Each of the durations was followed by an interstimulus interval (ISI) for 1 second or for 5 seconds (presented 10 times each). Durations and ISIs were randomly assigned across each run.
Tests showed that time estimation for the 600-millisecond condition was impaired in migraineurs, who significantly overestimated the duration of the stimulus. For the 600-millisecond condition, they estimated the duration of the stimulus presentation at 1.17 (0.34) seconds with an ISI for 1 second compared with 0.87 (0.19) seconds in the control group (P < .05). With an ISI for 5 seconds, estimation of the duration was 1.11 (0.60) seconds in the patient group and 0.90 (0.19) seconds in the control group (P < .05).
For 3-second and 5-second duration reproduction tasks, migraine patients in the setting of an ISI for 1 second and for 5 seconds did not show impairment in time perception compared with controls.
“Our study finds that migraineurs’ ability of time perception is impaired interictally,” write the authors. “To be specific, the impairment exists in the range of 600 milliseconds, whereas the ability of time perception in the range of long duration [3 seconds and 5 seconds] remains normal.”
Impairment in time perception may lead to inaccurate estimates of the duration of an event, thereby influencing the life of an individual, according to the authors. For example, it will affect a person’s behavioral response to a painful stimulus because the person misestimates the duration of the stimulus, they write.
Research has suggested that perception of time involves several cognitive functions, including perception, attention, and memory. Some evidence indicates that the cerebellum is involved in motor timing.
“In consideration of the correlation between time perception in milliseconds and the role of the cerebellum, we speculate that the overestimation of time intervals in the millisecond range may reflect a slowing in the cerebellar event timing system, and there is functional impairment in the cerebellum of migraineurs interictally,” the authors write.
“The cerebellar function change may alter cerebellar intervention in time processing, which may represent the underlying pathophysiology of the perceptual dysfunction.”
Further efforts are necessary to explore the change in time judgments in migraineurs and other headache patients, such as those with cluster headache and tension headache, the authors conclude.
The authors have reported no relevant financial relationships.
Headache. Published online July 23, 2012. Abstract