Peripheral magnetic stimulation effects on brain activity in older adults with schizophrenia – a randomized controlled pilot study

Objective To conduct an exploratory neurophysiological pilot analysis of transient resting-state EEG alterations induced by a single peripheral magnetic stimulation (PMS) session in older adults with schizophrenia. Methods In a randomized sham-controlled study, 40 older inpatients received either active PMS (30 minutes on the quadriceps) or a sham intervention. Eyes-closed resting-state EEG (59 channels) was recorded pre- and post-intervention. Spectral power (δ, θ, α, β, γ), scalp topographies, and weighted phase lag index (dwPLI) functional connectivity were analyzed. Results Active PMS induced significant, frequency-specific changes: decreased δ/θ power and increased α/β/γ power. Topographically, low-frequency reductions were prominent in the midline-right hemisphere, while high-frequency enhancements occurred in frontoparietal regions. Connectivity analyses revealed a dual pattern: potentially strengthened long-range δ-θ coupling (frontal/midline to right posterior) and enhanced short-range high-frequency synchrony in frontal and lateral parietal areas. These dwPLI connectivity findings derive from exploratory analyses and were not prespecified formal study outcomes. The sham group showed no comparable changes. Conclusions This exploratory pilot study identified transient band-specific resting-state EEG shifts following one PMS session, including reduced low-frequency oscillations and elevated high-frequency power and connectivity in older adults with schizophrenia. These preliminary neurophysiological patterns require replication in larger controlled trials; no definitive clinical therapeutic inferences can be drawn from this small exploratory dataset. Significance This exploratory pilot analysis offers preliminary novel electrophysiological observations of PMS-related brain rhythm modulation in older adults with schizophrenia. These exploratory findings lay a foundation for future larger, confirmatory neurophysiological trials peripheral magnetic stimulation; schizophrenia; resting-state EEG; older adults. Clinical trial registration ClinicalTrials.gov , identifier NCT07194460.