Preplanned versus online control in baseball batting: Effects of temporal constraints and spatial uncertainty.

How does the sensorimotor system control ultrarapid interceptive actions that must be completed within a few hundred milliseconds under high temporal pressure and spatial uncertainty? Such actions, as exemplified by baseball batting, require sophisticated coordination of perceptual and motor processes. The present experiment examined how these ultrafast interceptive movements are controlled by means of predictive and online processes as temporal constraints and spatial uncertainty were systematically varied. Eighteen skilled collegiate batters performed a high-fidelity virtual reality batting task in which time-to-contact (TTC: 500-375 ms) and spatial uncertainty (high/low) were orthogonally manipulated. Hitting performance (contact rate) remained stable at longer TTCs but declined once the available time fell below ∼425-400 ms, identifying a temporal boundary. As temporal urgency increased, swing initiation occurred earlier while swing duration remained constant, indicating predictive timing adjustments. However, timing error increased sharply near this boundary. Nevertheless, bat-head trajectories continued to diverge according to pitch location, and trial-by-trial variability increased at shorter TTCs, revealing within-swing online adjustments. Together, these findings demonstrate that the sensorimotor system coordinates predictive planning and online visual-motor adjustment within a narrow temporal window, suggesting that predictive and online control are integrated in a hybrid manner in temporal-urgency interception. (PsycInfo Database Record (c) 2026 APA, all rights reserved).