No evidence for a late locus of task switch effects

Area of Science:

• Cognitive Psychology
• Neuroscience
• Human Factors

Background:

• Task switching incurs longer reaction times compared to task repetition.
• Existing models propose switch costs occur during perceptual or response selection stages.
• Previous research suggested a motor locus for switch costs based on response-locked potentials.

Purpose of the Study:

• To re-evaluate the locus of task switch costs.
• To investigate potential methodological artifacts in prior research on switch costs.
• To determine if task switching influences motor-related potentials.

Main Methods:

• Replication of the Hsieh and Liu (2005) experiment.
• Careful control of methodological factors to avoid artifacts.
• Analysis of stimulus-locked and response-locked lateralized readiness potentials.

Main Results:

• Task switching significantly affected stimulus-locked lateralized readiness potentials.
• No significant effect of task switching was observed on response-locked lateralized readiness potentials.
• Findings contradict previous evidence for a late, motor locus of switch costs.

Conclusions:

• The locus of task switch costs is likely not in the motor stage.
• Evidence supports a role for response selection in task switching.
• Methodological considerations are crucial for accurately localizing cognitive processes.