Transcranial Magnetic Stimulation (TMS) is a non-invasive treatment that uses magnetic pulses to influence activity in targeted areas of the brain. Unlike medications, which work throughout the body, TMS therapy delivers stimulation to specific brain regions involved in mood regulation and other functions.
Scientists continue to study exactly how TMS produces lasting clinical effects. Current evidence suggests that its effects involve changes in neuronal activity, communication between brain networks, and the brain’s ability to adapt.
During TMS, a treatment coil is positioned near the scalp over a specific area of the brain. Rapidly changing electrical currents within the coil create a magnetic field, which passes through the skull and induces an electrical field in the underlying brain tissue. This can influence the activity of cortical neurons.
The stimulation is carefully controlled. Factors such as the treatment target, intensity, frequency, pulse pattern, and treatment schedule can influence how the brain responds.
Because the magnetic field primarily reaches superficial cortical areas, TMS can also influence connected regions through the brain’s existing neural pathways.
Neurons communicate by generating electrical signals and transmitting information through interconnected networks. TMS can temporarily alter the excitability of neurons in the targeted region.
The effects depend partly on how stimulation is delivered. Different frequencies and patterns can produce different changes in cortical excitability. Research has demonstrated that repetitive stimulation can produce effects that persist beyond the immediate stimulation period.
Importantly, TMS does not simply switch a single part of the brain “on” or “off.” The brain functions through interconnected circuits, so stimulation of one region can influence activity in other connected areas.
One of the important concepts in understanding TMS is neuroplasticity, which refers to the brain’s ability to change and adapt in response to activity and experience.
Repeated TMS stimulation may influence synaptic plasticity, meaning it can affect how effectively neurons communicate with one another. Research has identified TMS effects resembling mechanisms involved in long-term potentiation and long-term depression, although the exact therapeutic mechanism remains an active area of research.
This may help explain why TMS is generally delivered through a series of sessions rather than as a single treatment. Repeated stimulation may produce changes that build over time.
Depression involves multiple brain circuits rather than a single isolated brain region. Research using neuroimaging has found that TMS can influence activity and connectivity beyond the immediate stimulation site.
For example, stimulation of prefrontal regions has been associated with changes involving deeper and interconnected areas involved in mood regulation, including the anterior cingulate cortex, amygdala, and hippocampus. Changes in broader networks, including the default mode network, have also been observed.
These findings suggest that TMS may work partly by influencing communication across larger neural networks rather than producing an effect only where the treatment coil is placed.
The brain is highly adaptable, and therapeutic changes may require repeated stimulation. A TMS treatment course therefore typically consists of multiple sessions delivered according to a structured protocol.
At Scottsdale TMS & Spravato, treatment begins with an evaluation and brain mapping process to identify the appropriate treatment area and establish an individualized protocol. The treatment is then delivered while the patient remains awake and can return to normal activities afterward.
Our Team monitors treatment response throughout the course and can make adjustments when clinically appropriate. Dr. Michael Vines brings extensive psychiatric experience to the evaluation and treatment process.
Understanding the science behind TMS can help explain why treatment is different from simply taking a medication or attending a therapy session. TMS directly applies controlled magnetic stimulation to a targeted brain region, while the resulting effects can extend through connected neural circuits.
However, researchers are still investigating the precise biological processes responsible for clinical improvement. Current evidence supports changes in neuronal excitability, connectivity, and plasticity, but there is not one single mechanism that fully explains every patient’s response.
TMS affects the brain by using controlled magnetic pulses to influence neuronal activity in targeted cortical regions. Repeated stimulation can alter cortical excitability and may contribute to changes in synaptic plasticity and communication across connected brain networks.
For depression, research suggests that these effects can extend beyond the immediate treatment site and influence circuits involved in mood regulation. While the precise mechanism of therapeutic TMS continues to be studied, its neurobiological effects help explain why treatment is delivered through repeated, carefully calibrated sessions. Scottsdale TMS & Spravato provides personalized TMS treatment designed around individual clinical needs and ongoing treatment response.
Dr. Vines has practiced psychiatry in Arizona for for over 25 years and has experience working with diverse populations that include children, adolescents, adults, geriatrics, SMI patients, and the chemically dependent.
August 4, 2026
