Somatosensory Mismatch Negativity in Children: A Narrative Review of Current Evidence and Methodological...

Somatosensory mismatch negativity (sMMN) constitutes an electrophysiological marker that initially reflects preattentional processing and subsequently indexes automatic somatosensory deviance detection. While its application in adult populations is gradually expanding, the establishment of a standardized and reproducible methodology for eliciting and analyzing sMMN in pediatric populations remains uncertain. To determine whether the published literature provides a clear, consistent, and standardized methodology for sMMN assessment in individuals under 18 years. A search was conducted in PubMed (11), Scopus (6), Web of Science (6), DOAJ (1), Europe PMC (6), Embase (0), ClinicalKey (0), Cochrane Library (0) and ClinicalTrials.gov (0) database from inception to 18 August 2025. Eligible studies included research assessing sMMN using somatosensory oddball paradigms in participants <18 years. Inclusion criteria (participants younger than 18 years, the use of the oddball paradigm to evaluate somatosensory mismatch negativity, and clinical reports, single-case reports or experimental studies including both typically developing children and children with neurological conditions, published in English), and exclusion criteria (exclusivity for adult participants, and narrative reviews or editorials) were defined a priori, as well as the screening procedures and quality assessment methods. Two reviewers independently performed study selection and data extraction, with a third reviewer resolving disagreements. Risk of bias was assessed using the MMAT (mixed methods appraisal tool). Due to substantial heterogeneity in paradigms and outcome reporting, results were synthesized narratively. Four studies met inclusion criteria. Methodological diversity was pronounced across everything except task type that was passive. There is not a consensus regarding stimulation parameters. Risk of bias assessment revealed frequent concerns related to incomplete reporting and variability in analytic choices. The small number of studies, inconsistent methodological reporting, and absence of harmonized protocols limited comparability. Current evidence does not support the existence of a standardized methodology for assessing sMMN in children. Future studies should adopt harmonized stimulation paradigms and transparent, reproducible reporting standards to enable cross-study comparability and clinical translation.