Four dimensions of individualization in brain stimulation for psychiatric disorders: context, target, dose, and timing.

Non-invasive Brain Stimulation (NIBS) technologies, including transcranial electrical (tES) and magnetic (TMS) stimulation, have emerged as promising interventions for various psychiatric disorders. FDA-approved TMS protocols in depression, OCD and nicotine use disorder provide a meaningful improvement. Treatment efficacy however remains inconsistent across individuals, and one relevant reason is intervention effect variability based on individual factors. There is a growing effort to develop individualized interventions, reinforced recently by FDA approval of a new TMS protocol that includes individualized fMRI-based targeting along with other modifications with higher reported effect size than previous "one size fits all" protocols. This paper discusses the dimensions for individualizing tES/TMS protocols to enhance therapeutic efficacy. We propose a multifaceted approach to personalizing NIBS, considering four levels: (1) context, (2) target, (3) dose, and (4) timing. By addressing inter- and intra-individual variability, we highlight a path toward precision medicine using individualized Brain Stimulation to treat psychiatric diseases. Despite challenges and limitations, this approach encourages broader and more systematic adoption of personalized Brain Stimulation techniques to improve clinical outcomes.