Auditory cortical potentials indices in phonological awareness: a systematic review.

Objective: To investigate whether the N1, P2, and N2 auditory evoked potentials reflect performance in phonological awareness tasks.

Design: A systematic search was conducted using keywords such as "cortical auditory potential," "N1," "P2," "N2," and "phonological awareness" across databases (CINAHL, Embase, PubMed/Medline, Web of Science) and gray literature (Google Scholar, OpenGrey, ProQuest).

Study sample: Human studies were included if they analysed N1, P2, and/or N2 components in relation to phonological awareness tasks, either by correlating these components with task performance or comparing latency and amplitude across groups with different levels of phonological awareness.

Results: Of 371 records, seven studies (2004-2021) from Brazil, the Netherlands, China, Canada, and Finland were selected. Four were case-control studies, two were intervention studies, and one was observational. Four used phonological priming, and three used standardised phonological awareness assessments. Five studies suggested that the N1, P2, and N2 components may predict phonological awareness performance.

Conclusion: The N1, N2, and P2 components are potential predictors of phonological processing. Tasks involving phonological priming-especially rhyme and alliteration-modulate N1 and N2, while the P2 component, though less studied, appears to be sensitive to alliteration. Future research should explore these relationships in greater detail for clinical applications.