Arousal modulates temporal preparation under increased time uncertainty: Evidence from higher-order sequential...

Area of Science:

• Cognitive Psychology
• Neuroscience
• Human Performance

Background:

• Reaction time tasks with variable foreperiods (FP) exhibit complex patterns like the variable-FP effect and sequential FP effects.
• Existing models, such as trace-conditioning and dual-process accounts, offer different explanations for these phenomena, involving associative learning or preparation and arousal dynamics.

Purpose of the Study:

• To investigate higher-order sequential foreperiod effects on reaction time performance.
• To examine how temporal context (average FP length) and reaction mode (simple vs. choice) modulate these sequential effects.
• To test predictions derived from the dual-process model regarding arousal contributions.

Main Methods:

• Five experiments were conducted using reaction-time tasks with unpredictably varied foreperiods.
• Performance in long foreperiod trials was analyzed based on the length of the two preceding foreperiods.
• The temporal context (average FP length) and reaction mode were systematically varied across experiments.

Main Results:

• Slower reaction times in long-long-long FP sequences compared to short-short-long sequences were observed.
• This higher-order sequential effect was absent in a short-FP context but emerged clearly within a long-FP context.
• The findings indicate that the influence of preceding foreperiods on current performance is context-dependent.

Conclusions:

• Transient changes in arousal levels significantly contribute to sequential performance effects in variable-FP reaction time tasks.
• The results align with the dual-process model, suggesting that arousal fluctuations, modulated by FP history and context, play a crucial role in temporal preparation.
• This provides evidence against purely associative learning accounts for these specific sequential effects.