Neural processing of goal and non-goal-directed movements on the smartphone
The discrete behavioral events captured on the smartphone touchscreen may help unravel real-world neural processing. We find that neural signals (EEG) surrounding a touchscreen event show peculiarly contralateral motor preparation, visual processing, and the consolidation of information. We leveraged these events in conjunction with kinematic recordings of the thumb and an artificial neural network to separate highly similar movements according to whether they resulted in a smartphone touch (goal-directed) or not (non-goal-directed). Despite their kinematic similarity underscored by the model, the signatures of neural control of movement and the post-movement processing were substantially dampened for the non-goal-directed movements, and these movements uniquely evoked error-related signals. We speculate that these unnecessary movements are common in the real world and although inconsequential the brain still provides limited motor preparation and tracks the action outcome. Real-world behavior is composed of neural processes that are difficult to capture in conventional laboratory-based tasks.