Electroconvulsive therapy (ECT) uses brief, controlled electrical pulses to trigger a short seizure in the brain while you’re under general anesthesia. That seizure changes how brain cells communicate, shifting the balance of key chemical messengers involved in mood, motivation, and thought. It’s one of the most effective treatments available for severe depression, with a typical course running 6 to 12 sessions over several weeks.
How ECT Changes Brain Chemistry
The therapeutic seizure lasts roughly 30 to 60 seconds, but the chemical ripple effects persist much longer. ECT influences the release, reuptake, and receptor sensitivity of three neurotransmitters central to mood regulation: serotonin, norepinephrine, and dopamine.
Serotonin changes appear especially important. Brain imaging studies using PET scans show that ECT reduces the binding activity of two major serotonin receptor types across the hippocampus, amygdala, and prefrontal cortex. That receptor “down-regulation” is similar to what antidepressant medications aim to do, just through a different route and often faster.
On the dopamine side, ECT activates the dopamine system at multiple levels, boosting dopamine release and altering receptor expression in areas tied to motivation, concentration, and attention. This likely explains why patients often notice improvements in drive and focus alongside mood lifting.
ECT also stimulates production of a protein called brain-derived neurotrophic factor, which supports the growth and repair of connections between nerve cells. Depression is associated with reduced levels of this protein, and restoring it may help the brain form healthier signaling patterns over time.
What Happens During a Session
Modern ECT looks nothing like its portrayal in older films. You lie on a treatment table and receive a short-acting anesthetic through an IV, typically one that wears off within about 5 to 10 minutes. Once you’re asleep, a fast-acting muscle relaxant is given to prevent your body from physically convulsing during the seizure. Your muscles may twitch slightly, but there’s no thrashing or pain.
The treatment team places electrodes on your scalp, either on both sides of the head (bilateral) or on the right side only (unilateral). A controlled electrical current passes between the electrodes for a few seconds, triggering the seizure, which the team monitors on an EEG. The entire procedure, from falling asleep to waking up, takes roughly 10 to 15 minutes. Most people are alert enough to leave the recovery area within an hour.
Conditions ECT Treats
ECT is most commonly used for severe major depression, particularly when medications haven’t worked or when the situation is urgent, such as active suicidal thinking or refusal to eat or drink. A standard course for depression runs 6 to 12 sessions, though some people need fewer and others more. Sessions are typically scheduled two or three times per week.
Beyond depression, ECT is considered a first-line treatment for catatonia, a condition where a person becomes unresponsive or extremely agitated and doesn’t improve with initial medication. It’s also used for malignant catatonia and neuroleptic malignant syndrome, both life-threatening emergencies. Severe mania and certain presentations of schizophrenia that resist other treatments are additional indications.
How Treatment Frequency Works
In the United States, sessions are commonly scheduled three times per week. In the UK, twice-weekly sessions are the norm. Research comparing the two schedules for bilateral ECT found that thrice-weekly treatment produces slightly faster improvement, but twice-weekly treatment causes fewer cognitive side effects. The American Psychiatric Association recommends two to three sessions per week, noting that frequency should be reduced if memory problems become a concern.
Treatment continues until symptoms remit or until improvement plateaus for two consecutive sessions. After the initial course, some people transition to maintenance ECT, with sessions spaced further apart (often monthly) to prevent relapse. The evidence base for the ideal maintenance schedule is still limited, so it tends to be tailored to the individual.
Memory and Cognitive Side Effects
Memory disruption is the side effect people worry about most, and it’s a real concern. ECT can temporarily scramble recall of events from the weeks and months leading up to treatment. A study tracking memory at multiple time points found that recall of events from many years earlier was initially disrupted but recovered almost completely by seven months after the final session.
The picture is different for more recent memories. Information learned just days before treatment can be permanently lost. For events from the one-to-two-year window before ECT, recovery is substantial but may remain incomplete. In practical terms, this means you might lose some specific memories from the period surrounding your treatment, while your long-term autobiographical memory largely stays intact.
During the treatment course itself, many people experience difficulty forming new memories or concentrating. These problems typically clear within a few weeks of finishing treatment. Unilateral electrode placement (right side only) and twice-weekly scheduling both reduce cognitive side effects compared to bilateral, thrice-weekly treatment.
Physical Side Effects
The most common physical complaints are headache, body aches, and nausea. In one study of 120 patients, about 21% experienced an immediate complication after a session: headache was the most frequent (roughly 9%), followed by body aches (about 6%), brief confusion or memory gaps (2.5%), and a temporary rise in blood pressure (3.3%). These effects are generally short-lived, resolving within hours. Some people report jaw soreness from the mouth guard used during the procedure.
Safety Profile
ECT carries the risks of any procedure involving general anesthesia, but its safety record is strong. A systematic review pooling data from over 766,000 treatments across 32 countries found an ECT-related mortality rate of 2.1 per 100,000 treatments. For context, the mortality rate for general anesthesia during surgical procedures is 3.4 per 100,000. In studies published after 2001, covering more than 414,000 treatments, only a single ECT-related death was reported. The greatest risks are for people with unstable heart conditions or raised pressure inside the skull, since the seizure briefly increases heart rate and blood pressure.