Electrophysiological correlates of the drift diffusion model in visual word recognition

Area of Science:

• Cognitive Neuroscience
• Computational Neuroscience
• Psychology

Background:

• Decision-making models often use drift-diffusion processes to explain evidence accumulation.
• Electrophysiological measures like event-related potentials (ERPs) offer insights into the timing of cognitive processes.
• Understanding the neural basis of decision parameters is crucial for cognitive modeling.

Purpose of the Study:

• To investigate the electrophysiological correlates of the drift rate parameter in cognitive decision making.
• To examine the relationship between drift rate variability and event-related potentials (ERPs) and theta band power.
• To explore the temporal dynamics of information accumulation during visual word processing.

Main Methods:

• Eighty-two participants performed a lexical decision task.
• Stimulus-dependent event-related potentials (ERPs) and theta frequency band power were recorded.
• A mass univariate approach analyzed correlations between drift rate parameters and neural activity.

Main Results:

• Individual differences in drift rate correlated with late positive complex (LPC) amplitudes.
• Within-subject differences in drift rates (word emotionality, item repetition) also related to LPC amplitudes.
• No significant correlations were found between drift rate and theta frequency band power.

Conclusions:

• Late positive complex (LPC) amplitudes may reflect the strength of memory traces and information accumulation.
• Results suggest a shared cognitive mechanism underlying drift rates and LPC modulation.
• The study offers a new perspective on the timeline of visual word processing and proposes LPC as a potential neurophysiological marker for information accumulation.