Blocked versus randomized presentation modes differentially modulate feedback-related negativity and P3b amplitudes.

Area of Science:

• Cognitive Neuroscience
• Electrophysiology

Background:

• Electrophysiological studies on feedback processing often use diverse stimuli, raising concerns about comparability.
• Understanding how feedback stimuli characteristics influence neural responses is crucial for accurate interpretation.

Purpose of the Study:

• To investigate if feedback stimuli type (facial expressions vs. symbols) and presentation mode (trial-by-trial vs. block-wise) differentially affect feedback-related negativity (FRN) and P3b.
• To identify potential confounds in electrophysiological studies of feedback processing.

Main Methods:

• Electroencephalography (EEG) was recorded during a time estimation task with two feedback types.
• Stimuli included explicit (facial expressions) and assigned valence (symbols) feedback.
• Feedback was presented in both trial-by-trial and block-wise formats.

Main Results:

• P3b amplitudes showed consistent variations with feedback type across both presentation modes.
• Blocked feedback presentation resulted in more distinct FRN peaks and larger effect sizes.
• Blocked presentation also revealed a significant relationship between FRN amplitudes and behavioral performance.

Conclusions:

• Both feedback stimulus type and presentation mode can systematically alter feedback-related event-related potentials (ERPs).
• Findings highlight potential confounds in FRN and P3b research.
• Caution is advised when interpreting P3b studies with mixed stimuli; blocked presentation is recommended for different feedback types.