Pediatric sensorimotor cortical responsiveness to intracerebral stimulation during stereoelectroencephalographic monitoring: Age effects and area specificity

Objective: This study was undertaken to determine how age influences clinical responsiveness to intracerebral electrical stimulation (IES) in children across primary and secondary sensorimotor cortices and to assess age effects on response complexity and area-specific responsiveness. Methods: A retrospective cohort of pediatric (≤16 years) stereoelectroencephalographic procedures was analyzed. A total of 1750 IESs were delivered in 33 implantations (31 patients). Precentral and postcentral gyri were considered as primary areas; secondary areas included premotor cortex (PREMOT), supplementary sensorimotor area (SSMA, including presensorimotor area), anterior/central cingulate (ACC), and pre-/postcentral opercula (PREC-OP and POSTC-OP). Clinical responses were classified as simple motor, sensory, language, or undefined. Complexity was coded as integrated (one coordinated action) or multiple (signs from different domains occurring together). Mixed-effects models were adjusted for antiseizure medication load, cognitive level/neurodevelopmental delay, and stimulation frequency (1 vs. 50 Hz). Age was modeled continuously (per year) and categorically (≤9 vs. >9 years). Results: Clinical response rate increased with age in the overall cohort (per-year incidence rate ratio [IRR] = 1.11, 95% confidence interval [CI] = 1.03–1.21, p =.007). Categorical modeling showed a higher rate in subjects aged >9 years (IRR = 1.89, 95% CI = 1.02–3.51, p =.044). Integrated responses did not vary with age, whereas multiple responses were more likely in older children (overall adjusted odds ratio [OR] = 3.65, 95% CI = 1.24–10.77, p =.019; without postdischarge: adjusted OR = 5.30, 95% CI = 1.38–20.36, p =.015). Using PREMOT as reference, all other regions were more responsive, forming two clusters: lower (ACC, PREC-OP/POSTC-OP) and higher (SSMA, precentral, postcentral); SSMA showed rates comparable to primary cortices. Significance: Pediatric cortical responsiveness to IES rises with age and is independent of medication burden, cognitive level, and stimulation frequency. Older children also show more multidomain responses, consistent with developing large-scale integration. These results can inform age-aware stimulation mapping in clinical practice.