Task switching: effects of practice on switch and mixing costs

Area of Science:

• Cognitive Psychology
• Neuroscience

Background:

• Task switching involves performance costs when alternating between tasks (switch costs) or when tasks share stimuli/responses (mixing costs).
• Previous research shows practice can reduce these costs, particularly with bivalent stimuli.
• Univalent stimuli may offer a different pathway for cost reduction in task switching.

Purpose of the Study:

• To investigate if extensive practice eliminates mixing and switch costs in a task-switching paradigm using univalent stimuli.
• To compare the effects of practice on univalent versus bivalent response conditions in task switching.

Main Methods:

• Participants practiced switching between visual and auditory tasks over eight sessions.
• Two groups were tested: one with univalent responses (visual-manual, auditory-verbal) and one with bivalent responses (visual-manual, auditory-manual).
• Mixing and switch costs were measured before and after practice.

Main Results:

• Both univalent and bivalent conditions exhibited significant mixing and switch costs initially.
• After eight practice sessions, mixing costs were substantially reduced in both conditions.
• Switch costs, however, remained evident in both univalent and bivalent response groups.

Conclusions:

• Extensive practice effectively eliminates mixing costs in task switching, irrespective of stimulus-response mapping bivalence.
• Switch costs persist even after prolonged practice, indicating a different underlying mechanism compared to mixing costs.
• The findings highlight the differential impact of practice on various components of cognitive control during task switching.