SENSE OF AGENCY SHAPES THE ALLOCATION OF VISUOSPATIAL ATTENTION

[Aims] Sense of agency (SoA) refers to the subjective feeling that one is in control of one’s own actions. Present study is to investigate how spatial attention is dynamically allocated relative to movement direction during action control, and how this allocation relates to the perceived SoA. [Methods] Twenty-three participants completed three task sets, each consisting of a movement task under one SoA condition (High, Low, or Observe) followed by a visuospatial attention task. Participants were instructed to operate a cursor horizontally toward a fixed destination, with the cursor movement containing 20% noise in High and 80% noise in Low. In Observe, subjects passively pursued the cursor's movement without generating self-motion. In the visuospatial attention task, participants were required to press the corresponding button as quickly as possible after a target appeared. Targets were classified by location as either congruent (FW) or incongruent (BW) with the cursor movement direction. [Results] Reaction times (RTs) were significantly prolonged at BW compared with FW in Low and Observe, whereas no direction-related differences were observed in High. RTs slopes, defined as the slope of a simple linear regression fitted to RTs across three target positions within FW or BW, were significantly reduced in FW in Low relative to High. [Conclusion] Lower SoA and observation was associated with asymmetric spatial attention, whereas strong SoA was accompanied by spatially symmetric attentional allocation. In addition, when SoA was reduced, spatial gradients aligned with the intended movement direction reflected increased attentional focus toward the explicit movement destination.