Joint Simon Task, self-other integration, joint action, compatibility effect, nonspatial, teaming


The joint Simon task is a cognitive reaction time task used to assess shared representations and self-other integration when performing a collaborative task with a partner. However, it is unclear if the underlying mechanisms are specific to representing spatial information or are more general. The objective of the current study was to assess a nonspatial joint Simon compatibility effect. Participants completed the joint Simon task with a partner while seated side-by-side, face-to-face, back-to-back, or with their partner not in the room. They completed the task three times, once with horizontal stimuli (left/right of center), once with vertical stimuli (above/below center), and once with central stimuli (at center). In the central task, compatibility was in color where participant responses (assigned red or green response buttons and gloves) were compatible or incompatible to the stimuli (colored red or green). Results showed no significant compatibility effect for any task in any response orientation condition, indicating no evidence of a nonspatial compatibility effect. Results even failed to replicate the standard joint Simon effect of a spatial compatibility effect in the horizontal task when seated side-by-side. However, exploratory analyses showed a significant nonspatial color compatibility effect in the central task for those assigned green in the side-by-side condition only, indicating that the presence of color in the participants' response (i.e., colored responses button and gloves) may have interfered with representing spatial information. This finding has implications for both theory and application of the joint Simon task, indicating it is sensitive to small changes, occurs for features besides location, and may be most effective when seated side-by-side. Additionally, the broader implications for the cognitive and practical study of joint action show the importance of how different features influence shared representations, how different colors are perceived and represented, and how different response orientations influence performance.

Completion Date




Committee Chair

Sims, Valerie


Doctor of Philosophy (Ph.D.)


College of Sciences



Degree Program

Human Factors and Cognitive Psychology






In copyright

Release Date

May 2025

Length of Campus-only Access

1 year

Access Status

Doctoral Dissertation (Campus-only Access)

Campus Location

Orlando (Main) Campus

Accessibility Status

Meets minimum standards for ETDs/HUTs

Restricted to the UCF community until May 2025; it will then be open access.