Sentence context affects the brain response to masked words

Area of Science:

• Cognitive Neuroscience
• Psycholinguistics
• Neuroscience

Background:

• Traditionally, word processing was seen as automatic, with context influencing later stages.
• This study challenges that by investigating context effects on unconsciously processed words.

Purpose of the Study:

• To investigate the impact of sentence context on word processing, particularly for words not consciously perceived.
• To explore the neural underpinnings of contextual influence using event-related potentials (ERPs).

Main Methods:

• Recording ERPs while participants processed sentences with congruent or incongruent endings.
• Manipulating word visibility by masking or unmasking sentence-final words.
• Analyzing the N400 component (300-500ms post-word onset) for congruity effects.

Main Results:

• Congruent sentence endings elicited less negative ERPs (N400 effect) than incongruent ones for both masked and unmasked words.
• The N400 congruity effect was smaller, later, and more anterior for masked words compared to unmasked words.
• This suggests context influences word processing automatically and through controlled processes.

Conclusions:

• The N400 component reflects both automatic and controlled aspects of contextual priming.
• Findings suggest a link between N400 neural generators and conceptual short-term memory.
• Conceptual short-term memory dynamically structures information triggered by perceptual input.