Dividing attention influences contextual facilitation and revision during language comprehension

Area of Science:

• Cognitive Neuroscience
• Psycholinguistics

Background:

• Language comprehension often occurs amidst distractions.
• The role of sustained attention in sentence processing, particularly information integration and prediction revision, is under-examined.

Purpose of the Study:

• To investigate the impact of attention on sentence processing.
• To examine how sustained attention influences semantic access and prediction revision during language comprehension.

Main Methods:

• A novel dual-task paradigm was employed.
• Participants performed a sentence reading task (varying constraints and endings) concurrently with a dot-motion tracking task.
• Electroencephalography (EEG) was recorded to measure brain activity, specifically the N400 component and post-N400 frontal positivity.

Main Results:

• Under full attention, the N400 amplitude (semantic access) showed graded facilitation based on contextual strength and fit.
• Divided attention attenuated this context-based N400 facilitation, indicating reduced message-level representation building.
• Prediction violation effects (post-N400 frontal positivity) were unaffected by attention division, but posterior effects emerged under divided attention.

Conclusions:

• Sustained attention is vital for efficient semantic integration and building comprehensive message representations.
• Predictive processing during sentence comprehension is robust, engaging even under divided attention.
• Processing unexpected information under divided attention may necessitate additional cognitive resources, potentially reflected in posterior EEG effects.