The Effect of Contextual Cues on Goal-Directed Reaches to Multisensory Targets

Abstract

When reaching for an object on a crowded table, visual information about the position of other objects should contribute to the movement plan to avoid spills and bumps. Previous research has found that movements to visual targets were more accurate when non-target visual information (e.g., contextual cues) were present in the reaching environment compared to when reaching in a dark environment. Although visual context plays a role in movements to visual targets, it is unknown if this information is also used when making movements to somatosensory targets (e.g., body positions). The goal of this study is to determine if the presence of visual contextual cues also affects movements to somatosensory targets. Eleven neurologically-healthy participants performed upper-limb reaches to unseen somatosensory targets and seen visual targets with and without contextual cues. To assess the impact of contextual information, radial error, angular error and temporal kinematic variables (e.g. time to peak velocity) were computed. Our results indicated that the presence of contextual cues did reduce radial error for movements to both target modalities. These results provide evidence that contextual information may also contribute to movements to somatosensory targets, indicating that external visual cues could play a role in how humans localize body position.