Transcranial Magnetic Stimulation, or TMS, is a non-invasive treatment that uses magnetic fields to stimulate nerve cells in the brain. It is approved for treating certain conditions, such as major depressive disorder, obsessive-compulsive disorder, and migraine headaches. Many individuals considering TMS therapy often wonder about its potential effects on memory. This article addresses whether TMS causes memory loss and clarifies current research findings.
How TMS Interacts with Brain Function
TMS therapy works by delivering focused magnetic pulses to specific areas of the brain. These magnetic fields can painlessly pass through the skull and induce small electrical currents within the brain tissue. Targeted regions include the prefrontal cortex, which can be underactive in depression. By modulating the activity of these nerve cells, TMS aims to restore more balanced brain function. The magnetic pulses can either excite or inhibit neuronal activity, depending on the frequency and intensity of the stimulation.
Does TMS Cause Memory Loss?
Clinical studies and widespread clinical use do not indicate that TMS causes permanent memory loss. Research consistently shows that TMS is safe for cognitive function, including memory. Some individuals might report mild, temporary cognitive effects, such as difficulty with word recall or transient confusion, during or immediately after a treatment session. These effects are rare, resolve quickly without lasting impact.
Multiple studies have investigated the cognitive effects of TMS, particularly in patients undergoing treatment for depression. These investigations include comprehensive neuropsychological testing before and after a course of TMS. The findings from such studies support the conclusion that TMS does not impair memory. In fact, some research suggests that cognitive functions, including certain aspects of memory, can either remain stable or even show improvement following TMS therapy.
Memory Changes During Depression Treatment
Depression itself impairs cognitive functions, including concentration, processing speed, and memory. Individuals experiencing depression may report difficulties with recalling information, maintaining focus, or making decisions. These cognitive symptoms are a recognized part of the depressive illness and can significantly impact a person’s daily life. Successful treatment of depression can lead to improvements in these associated cognitive deficits.
When TMS effectively treats depression, patients may experience an improvement in their overall cognitive abilities, including memory. This occurs because the underlying depressive illness, which was contributing to the memory issues, is being alleviated. Therefore, rather than causing memory loss, TMS can indirectly lead to a perceived improvement in memory as the symptoms of depression diminish. This distinction is important for understanding the relationship between TMS, depression, and cognitive function.
Other Common TMS Side Effects
While memory loss is not a typical side effect, TMS therapy does have other common, mild, and temporary side effects. Patients may experience scalp discomfort or mild pain at the treatment site during or immediately after the magnetic pulses are delivered. Headaches are also a frequent complaint, mild and manageable with over-the-counter pain relievers. These symptoms diminish over the course of the treatment series as the brain adjusts to the stimulation.
Some individuals might also experience muscle twitching in the face, jaw, or scalp during the treatment. These twitches are a direct response to the magnetic pulses stimulating superficial nerves and are not a cause for concern. A rare but serious risk of TMS is seizure, with the risk approximately 0.003% per treatment session.