Paced finger-tapping abnormalities in bipolar disorder indicate timing dysfunction.

Area of Science:

• Neuroscience
• Psychiatry
• Chronobiology

Background:

• Impaired time perception is linked to severe psychiatric disorders.
• Cerebellum and basal ganglia, involved in subsecond timing, are implicated in bipolar disorder pathophysiology.
• Subsecond interval timing in bipolar disorder remains understudied.

Purpose of the Study:

• To investigate subsecond interval timing in individuals with bipolar disorder.
• To characterize internal timing processes using paced finger-tapping tasks.
• To explore the relationship between timing variability and bipolar disorder.

Main Methods:

• 42 bipolar disorder patients and 42 controls performed a paced finger-tapping task.
• Tasks included synchronization to an auditory stimulus and continuation of the pace without input.
• Timing variability was decomposed into clock and motor components using the Wing-Kristofferson model.

Main Results:

• Bipolar disorder participants demonstrated significantly greater timing variability than controls.
• This increased variability was consistent across synchronization and continuation tasks, and different effector conditions.
• Analysis revealed higher internal clock variability in bipolar disorder patients, with no difference in motor implementation variability.

Conclusions:

• Internal timing mechanisms are disrupted in bipolar disorder, irrespective of current symptom status.
• Elevated clock variability in bipolar disorder may be associated with cerebellar abnormalities.
• These findings highlight timing deficits as a potential endophenotype of bipolar disorder.