Dual-Task Processing With Identical Stimulus and Response Sets: Assessing the Importance of Task Representation in...

Area of Science:

• Cognitive Psychology
• Neuroscience
• Human Factors

Background:

• Dual-task interference, the difficulty in performing two tasks simultaneously, is commonly measured by comparing dual-task performance to single-task performance.
• Traditional methods complicate interpretation by altering stimulus processing or response demands between single- and dual-task conditions.

Purpose of the Study:

• To introduce and validate a novel dual-task procedure that isolates the effects of task representation on performance.
• To differentiate interference stemming from task representation versus stimulus/response processing.

Main Methods:

• Developed a paradigm where stimulus processing was held constant while manipulating the number of tasks.
• Participants responded to stimulus pairs, with one condition (two-task set) featuring one-to-one stimulus-response mappings and another (one-task set) requiring integrated stimulus pair processing.

Main Results:

• Bimanual responses were slower than unimanual responses in the two-task set, consistent with typical dual-task interference.
• Conversely, unimanual responses were slower than bimanual responses in the one-task set.
• Performance differed significantly across conditions despite identical stimuli and response requirements.

Conclusions:

• Dual-task costs are significantly influenced by the interfering effects of task representation.
• The findings suggest that cognitive limitations in performing multiple tasks may stem from how tasks are internally organized and represented, not solely from increased processing load.