Task-order representations in dual tasks: Separate or integrated with component task sets?

Area of Science:

• Cognitive Psychology
• Neuroscience
• Human Factors

Background:

• Deciding task execution order is vital for simultaneous task performance.
• Response order control is influenced by bottom-up (stimulus) and top-down (instructional) factors.
• Prioritization of certain response modalities (e.g., oculomotor tasks) affects task order.

Purpose of the Study:

• Investigate whether task-order representations are coded separately or integrated within task sets.
• Examine task-order coding during unpredictable trial-to-trial task switching.
• Determine if task order is represented in a task-specific manner.

Main Methods:

• Combined oculomotor and manual/pedal tasks across three experiments.
• Introduced unpredictable task order switches between trials.
• Measured reaction times (RTs) to assess task-order switch costs.

Main Results:

• Observed robust task-order switch costs (longer RTs when task order switched).
• Demonstrated an asymmetry in task-order switch costs.
• Found it easier to switch to the prioritized task order (oculomotor task first) in most settings.

Conclusions:

• Task order is represented in an integrated, task-specific manner during frequent, unpredictable task switching.
• Task order representations are bound to the characteristics of component tasks, such as effector systems.
• Findings suggest a unified coding for task order linked to specific task demands and response modalities.