Less head motion during MRI under task than resting-state conditions.

Area of Science:

• Neuroimaging
• Cognitive Neuroscience
• Medical Physics

Background:

• Head motion is a significant confounder in neuroimaging, reducing data quality.
• Previous studies have not definitively established whether task-based functional MRI (fMRI) inherently reduces motion compared to resting-state fMRI.

Purpose of the Study:

• To investigate whether active cognitive tasks reduce head motion during fMRI compared to resting-state conditions.
• To identify demographic and clinical factors associated with head motion.
• To assess the implications of motion differences for comparing task and resting-state fMRI data.

Main Methods:

• Three fMRI experiments were conducted.
• Experiment 1: Compared motion during a memory encoding task versus rest.
• Experiment 2: Analyzed publicly available data (UCLA Consortium for Neuropsychiatric Phenomics LA5c Study) comparing multiple task conditions to rest.
• Experiment 3: Used a counter-balanced acquisition order to compare task and resting-state runs.
• Demographic (age, sex) and clinical (bipolar disorder, schizophrenia, ADHD) data were analyzed for motion correlations.

Main Results:

• Head motion was significantly lower during several cognitive task conditions compared to resting-state conditions across all experiments.
• In healthy controls, men and older individuals exhibited greater head motion.
• Patients with bipolar disorder and schizophrenia showed increased head motion compared to healthy controls and ADHD patients.
• Counter-balancing acquisition order confirmed task-related motion reduction, independent of scan position.

Conclusions:

• Cognitive tasks demonstrably reduce head motion during fMRI acquisition.
• Task-based fMRI may be beneficial for populations prone to motion, such as children and certain patient groups.
• Differences in head motion between task and resting-state fMRI complicate direct comparisons of functional neuronal networks.
• Incorporating tasks to minimize motion is recommended for structural MRI acquisition in research and clinical settings.