Scientists have identified a link between heart rate variability and the effectiveness of transcranial magnetic stimulation (TMS) as a treatment for depression, a finding that could personalize and optimize care for millions. Published October 14, 2025, the research reveals that fluctuations in heart rate during TMS sessions can predict whether a patient will experience notable enhancement in their depressive symptoms.
The findings, offering a potential biomarker for treatment response, are particularly significant given that TMS doesn’t work for everyone. Approximately one-third of individuals with depression do not achieve remission with TMS, leading to continued suffering and substantial healthcare costs. This new insight could allow clinicians to identify those most likely to benefit from TMS upfront, avoiding unneeded treatment and accelerating access to effective interventions for others.
Researchers found that patients exhibiting greater heart rate variability-the variation in time intervals between heartbeats-during TMS treatment demonstrated more substantial reductions in depression scores. The study suggests that a more flexible and adaptable nervous system, reflected in higher heart rate variability, might potentially be more receptive to the neuroplastic changes induced by magnetic brain stimulation.
The research team utilized TMS to target specific brain regions implicated in depression. Participants underwent multiple sessions while their heart rates were continuously monitored. Statistical analysis revealed a strong correlation between heart rate variability during treatment and clinical outcomes measured several weeks later.Further investigation is planned to validate these findings in larger, more diverse populations and to explore the underlying mechanisms driving this relationship.
