Hemispheric specialization for visual words is shaped by attention to sublexical units during initial learning

Area of Science:

• Cognitive Neuroscience
• Educational Psychology
• Neuroscience of Reading

Background:

• Learning to read involves establishing connections between written symbols and sounds.
• The brain's reading network is shaped by how individuals learn to map graphemes to phonemes.
• Instructional methods can influence the neural pathways involved in word recognition.

Purpose of the Study:

• To investigate how selective attention to grapheme-phoneme mappings during learning affects brain circuitry for reading.
• To compare the neural processing of trained words versus transfer words under different learning conditions.
• To understand the impact of instructional approaches on the lateralization of reading-related brain activity.

Main Methods:

• Adults learned two novel scripts with different instructions: grapheme-phoneme focus versus whole-word memorization.
• Event-related potentials (ERPs) were recorded during a reading task involving trained and untrained words.
• Reaction times and ERPs were analyzed to assess word access and neural processing.

Main Results:

• Behavioral data suggested both trained and transfer words were accessed via sublexical units.
• A late, left-lateralized ERP response was more pronounced for transfer words than trained words.
• This enhanced lateralization for transfer words may indicate more effortful decoding.

Conclusions:

• Selective attention to grapheme-phoneme correspondences during learning drives the lateralization of reading circuitry.
• Different learning strategies can lead to distinct patterns of brain activation during word recognition.
• This study provides a model for how instructional choices shape the neural basis of reading.