Beyond Completion Time: A Multimodal Approach to Characterizing Eye-Hand Coordination During the Nine-Hole Peg Test in Multiple Sclerosis

Mahya Beheshti; Rajvardhan Gadde; Diana Maloku; Danae S. Manta; Bethany Lum; Silvana L. Costa; Todd E. Hudson; John-Ross Rizzo

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arXiv · 2610.04145

Beyond Completion Time: A Multimodal Approach to Characterizing Eye-Hand Coordination During the Nine-Hole Peg Test in Multiple Sclerosis

Mahya Beheshti·Rajvardhan Gadde·Diana Maloku·Danae S. Manta·Bethany Lum·Silvana L. Costa·Todd E. Hudson·John-Ross Rizzo

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Abstract

Multiple sclerosis (MS) can impair upper-extremity function through motor, sensory, cognitive, and visual deficits. Although the Nine-Hole Peg Test (9-HPT) is widely used to assess dexterity, completion time alone provides limited insight into the eye-hand coordination underlying performance. We characterized 9-HPT performance in nine people with MS (PwMS) and nine healthy controls using simultaneous eye tracking, markerless hand tracking, and object detection. Each peg cycle was divided into transport, manipulation and insertion, and return-to-bin phases. PwMS had longer overall completion times. Transport was prolonged with the non-dominant hand, manipulation was prolonged with the dominant hand, and return-to-bin duration was longer with both hands, representing the largest phase difference. PwMS also made approximately one additional fixation per peg and showed greater variability in gaze landing position during dominant-hand performance. Saccadic amplitude and mean placement error did not differ significantly between groups, and gaze generally preceded hand movement in both groups. These exploratory findings suggest that MS-related slowing is concentrated in phases requiring precise manipulation and transition to the next peg. Multimodal assessment of the 9-HPT can reveal coordination deficits not captured by completion time alone.

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Mahya Beheshti, Rajvardhan Gadde, Diana Maloku, Danae S. Manta, Bethany Lum, Silvana L. Costa, Todd E. Hudson, John-Ross Rizzo. 2026-10-02. Beyond Completion Time: A Multimodal Approach to Characterizing Eye-Hand Coordination During the Nine-Hole Peg Test in Multiple Sclerosis. https://arxiv.org/abs/2610.04145

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