FONO SENSE: a technological resource for recording the auditory N400 component

Area of Science:

• Neuroscience
• Developmental Psychology
• Speech and Hearing Sciences

Background:

• Phonological processing is crucial for reading development.
• The N400 component of Event-Related Potentials (ERPs) reflects semantic integration.
• Assessing phonological processing in dyslexia often relies on behavioral measures, with electrophysiological tools offering objective insights.

Purpose of the Study:

• To develop and validate a mobile application for phonological auditory electrophysiological assessment.
• To investigate the N400 component in adults and children with and without dyslexia during phonological tasks.
• To compare electrophysiological responses between different age groups and dyslexia status.

Main Methods:

• Development of a mobile application featuring congruent and incongruent phonological tasks (words and non-words).
• Recording of N400 Event-Related Potentials using a Biologic's Evoked Potential System during auditory-linguistic tasks with acoustic stimuli (/ba/, /da/) and app integration.
• Cross-sectional study involving 25 participants: 10 children with dyslexia, 5 children without dyslexia, and 10 adults without learning disorders.

Main Results:

• The developed application successfully elicited the N400 potential across all participant groups.
• Children with dyslexia exhibited significantly delayed N400 latency compared to adults without learning disorders in incongruent tasks.
• Adults without learning disorders showed a significant latency reduction in incongruent tasks, unlike other groups.

Conclusions:

• The mobile application serves as an effective tool for eliciting N400 potentials in phonological assessment.
• Electrophysiological findings indicate developmental differences in auditory-semantic processing, with adults demonstrating more efficient processing than children.
• The study highlights potential electrophysiological markers for identifying phonological processing differences associated with dyslexia.