When two actors perform different tasks: Still no evidence for shared task-sets in joint task switching.

Area of Science:

• Cognitive Psychology
• Social Cognition
• Human-Computer Interaction

Background:

• Joint task switching research has yielded conflicting findings regarding shared task-set representation between co-acting individuals.
• Previous studies explored variations in joint task switching, leading to differing conclusions about whether individuals adopt their partner's task.

Purpose of the Study:

• To investigate whether co-acting individuals share task-sets by examining switch costs in joint vs. solo task performance.
• To clarify the role of task cue knowledge versus co-actor presence in driving switch costs.

Main Methods:

• Replicated a joint task switching paradigm where two actors performed different tasks.
• Conducted experiments varying the presence of a co-actor and the nature of task cues (explicit names vs. arbitrary symbols).
• Measured switch costs in both joint and solo conditions.

Main Results:

• Switch costs were observed in both joint and solo conditions, with larger costs in the solo condition.
• Switch costs in the solo condition depended on explicit task names serving as cues, but not on arbitrary symbols.
• Switch costs persisted even before participants were fully instructed on the second task.

Conclusions:

• Switch costs in joint task switching are driven by participants' knowledge of task cues, not by the presence of a co-actor.
• The findings challenge the assumption that switch costs in joint conditions reflect shared task-sets between co-actors.
• Task representation is influenced by explicit task identification rather than shared performance context.