Dissociating proportion congruent and conflict adaptation effects in a Simon-Stroop procedure

Area of Science:

• Cognitive psychology
• Neuroscience
• Human experimental psychology

Background:

• Proportion congruent and conflict adaptation are key effects in cognitive control research.
• A central debate concerns whether these effects stem from shared or distinct cognitive control mechanisms.

Purpose of the Study:

• To investigate whether proportion congruency and conflict adaptation effects rely on the same or separate cognitive control mechanisms.
• To examine the transfer and generalization of the proportion congruent effect across different conflict types.

Main Methods:

• A training phase introduced a proportion congruency manipulation for one conflict type (Simon task).
• Pre-training and post-training phases presented two conflict types (Simon and Spatial Stroop) with a consistent incongruent-to-congruent ratio.
• Analyzed the transfer of the proportion congruent effect and the specificity of the conflict adaptation effect.

Main Results:

• The proportion congruent effect demonstrated sustained effects, transferring from training to post-training phases.
• This transfer generalized to both Simon and Spatial Stroop conflict types.
• The conflict adaptation effect was specific to the conflict type, observed only on consecutive trials of the same type, not on alternating trial types.

Conclusions:

• Results support the distinction between proactive (proportion congruent effect) and reactive (conflict adaptation effect) cognitive control mechanisms.
• The sustained and generalized nature of the proportion congruent effect suggests a proactive control strategy.
• The conflict-specific nature of conflict adaptation suggests a reactive control mechanism that adjusts trial-by-trial.