Parallel and serial task processing in the PRP paradigm: a drift-diffusion model approach

Area of Science:

• Cognitive Psychology
• Neuroscience
• Human Factors

Background:

• The debate on dual-tasking centers on whether tasks are processed serially (response selection bottleneck models) or in parallel (capacity-sharing models).
• Previous research has not definitively resolved whether central processing stages of two tasks can overlap or must occur sequentially.

Purpose of the Study:

• To investigate the mechanisms of dual-task processing by manipulating stimulus onset asynchrony (SOA) frequency and incorporating no-go trials.
• To differentiate between serial and parallel processing models using response time (RT) and drift-diffusion model (DDM) analyses.

Main Methods:

• Three experiments were conducted, manipulating SOA frequency (Experiments 1 and 2) and including no-go trials (Experiment 3).
• Response time (RT) analyses and drift-diffusion model (DDM) analyses were employed to assess processing dynamics.

Main Results:

• Findings were consistent across experiments but did not exclusively support either response selection bottleneck (RSB) or capacity-sharing models.
• SOA frequency appeared to influence adaptation to temporal patterns.
• Drift-diffusion model results and mean RTs suggested that participants' time expectancies played a significant role.

Conclusions:

• The study's results challenge strict adherence to either serial bottleneck or capacity-sharing models for dual-tasking.
• Participant time expectancies may be a crucial factor in mediating cognitive resource allocation during dual-task performance.
• Further research is needed to fully elucidate the interplay between temporal expectancies and dual-task processing.