Response selection in dual task paradigms: observations from random generation tasks.

Area of Science:

• Cognitive Psychology
• Neuroscience
• Human Factors

Background:

• Attention-demanding tasks show reduced performance when performed concurrently compared to individually.
• Dual task costs are a well-documented phenomenon in cognitive psychology.

Purpose of the Study:

• To investigate the underlying mechanisms of dual task costs.
• To determine if costs arise from supra-trial resource switching or within-trial response selection demands.

Main Methods:

• Twenty healthy volunteers performed verbal random number generation (RNG) and random movement generation (RMG) tasks.
• Tasks were performed individually and concurrently at varying rates.
• Performance quality (randomness) and bias were analyzed.

Main Results:

• Performance in both RNG and RMG tasks decreased at faster rates and when performed concurrently.
• No association was found between transient bias in one task and performance changes in the other during dual-tasking.
• This suggests that supervisory control or attentional resources are not switched between tasks.

Conclusions:

• Dual task costs are not mediated by the alternation of supervisory control or attentional resources.
• The findings support the hypothesis that mechanisms within each trial, specifically response selection demands, contribute significantly to dual task costs.