How Electroconvulsive Therapy Works

By: Kate Kershner  | 
1949: Dr. James G. Shanklin, staff psychiatrist at Western State Hospital, administers electric shock and anesthesia to a patient. The procedure changed exponentially in the ensuing decades.
© Bettmann/CORBIS

Key Takeaways

  • Electroconvulsive therapy (ECT) is a psychiatric treatment involving electrically induced seizures. Doctors primarily use ECT for severe depression or mania when other treatments have failed.
  • Modern ECT has evolved significantly since its inception, with improved methods reducing side effects like memory loss. However, controversy still exists regarding its use and effectiveness.
  • Studies indicate ECT may work by altering brain blood flow, metabolism or chemical function. It could also stimulate nerve growth, potentially improving mood and cognitive function in severely depressed patients.

Putting the words "electroconvulsive" and "therapy" together seems a bit counterintuitive. For many of us, seizures don't fit in the same category as therapeutic healing.

In pop culture, the image of electroconvulsive therapy (or ECT, but also referred to as electroshock or shock therapy) is often portrayed as at odds with recovery. You only need to be reminded of Jack Nicholson's character in "One Flew Over the Cuckoo's Nest" to render an image of ECT as psychiatric and physical abuse.


And as we'll see, the early treatments of ECT weren't exactly soothing -- they were done with the patient conscious, for one. But decades later, ECT is now generally accepted as a beneficial approach to severe depression -- The National Institute of Mental Health, the American Psychiatric Association, the American Medical Association and the U.S. Surgeon General all endorse the use of ECT [source: Reti]. Former presidential nominee Michael Dukakis' wife, Kitty Dukakis, even wrote a book "Shock" describing how modern ECT treatment has helped her with the debilitating depression that she suffered from.

While there are emerging theories as to why ECT might help those with severe depression (which we'll be discussing), no one is certain why it works. Even more puzzling is that ECT is often used when antidepressants are ineffective -- but, strangely, antidepressant therapy after treatment can help prolong the effects of the ECT [source: Hopkins Newsletter].

We're talking pretty specifically about ECT in this article, but keep in mind there are other therapies that are a bit like it.

  • Vagus nerve stimulation actually uses an implanted device to stimulate a nerve in the brain and affect mood (as well as epilepsy).
  • Repetitive transcranial magnetic stimulation (rTMS) uses a magnet instead of electricity to activate the brain.
  • Deep brain stimulation requires brain surgery, as electrodes are implanted in the brain and stimulated by generators in the chest.

But let's stimulate our own brain using a more traditional method and read about the history of ECT.


History of ECT

The idea that some sort of convulsive shock seemed to clear up mental disturbances isn't new; even Hippocrates noted that convulsions caused by malaria seemed to help patients with mental illness. The idea that electric shock could be used to clear up mental disturbances was actually based on a false idea -- that epileptics were less likely to suffer from schizophrenic symptoms [source: Encyclopædia Britannica]. In one of those strange twists of science, however, epileptic-type convulsions did seem to affect mood.

By the 20th century, psychiatrists were experimenting with insulin-shock therapy, where large doses of insulin were injected into a patient to bring on an hour-long or so coma [source: Encyclopædia Britannica]. The insulin would then be flushed from the system with a salt solution, and voila -- schizophrenic patients would recover. OK, they didn't always recover. But enough to make scientists explore the phenomenon more.


In 1938, two Italian scientists pioneered using electric shocks to jolt a man with delusions. After a few treatments, the delusions receded. By the 1940s, ECT was being used in the United States to treat depression, bipolar disorder and schizophrenia. But it's important to remember how different the early versions of ECT were compared to the more modern practice.

First off, early ECT didn't involve anesthesia. That means, of course, that a patient was aware of what was happening, which was very traumatic. No modern muscle relaxants were administered, so there was a big risk for the body to shake and jerk violently -- so much so that fractures would occur. The electric current was also higher than is used in modern practice, so the seizures were violent. The procedure also caused more extreme memory loss in patients, which is probably why popular culture portrayed it as leaving patients zombie-like and lobotomized.


Welcome to Your ECT Appointment

1998: Doctors at a New York hospital perform ECT on a patient to treat depression.
© Najlah Feanny/Corbis

ECT has come a very long way since it was first used as a form of therapy. No longer does a patient need to worry that her bones will break from violent jarring or that she'll be awake the whole time her brain is being shocked.

So let's walk through a modern ECT treatment and see what the actual event looks like, as well as what's happening to the brain. First off, you'll have already gone through a battery of blood tests, an electrocardiogram, psychological assessment and a physical exam to make sure that you're physically and mentally fit for ECT.


Unlike the old days, you'll be put under general anesthesia for the procedure, so an IV will be inserted into your arm for the medicine to knock you out. Medical staff will also include a muscle relaxant in the IV to ensure a less profound physical reaction to the seizure. However, a blood pressure cuff around one ankle will prevent the relaxant from entering the foot. The doctor will watch that foot to monitor the physical activity of the seizure. A mouth guard might also be provided to prevent you from chomping your tongue.

Most important, electrode pads are placed on your head. A bit larger than a quarter, these pads might be placed on just one side of the head (unilateral), or both (bilateral). After you're completely unconscious, the doctor will press a button on the ECT machine. An electric current travels through the machine to the electrodes, where they will then pass through to your brain. For about 60 seconds or less, you will undergo a seizure. But keep in mind that you won't appear to be doing so; the muscle relaxant should function so that only your non-medicated foot will move. An electroencephalogram (EEG) monitor will show sudden spikes in activity, of course, as it measures the electrical activity of your brain. While traditional ECT uses pulses administered for one millisecond, there's now a growing trend to use ultra-brief pulses -- 0.25-0.37 milliseconds -- which still cause the seizure but lead to less side effects after the treatment [source: John Hopkins Medicine].

And that's pretty much it; the whole thing usually lasts five or 10 minutes [source: Mayo Clinic]. After the meds wear off, you might show some confusion for a few hours. And according to Mayo Clinic, most ECT treatments in the United States are given two to three times weekly, for three to four weeks.


Does It Work? ECT Effectiveness

Before we go any further, we should make it clear that a small number of people with really severe mental illnesses receive ECT. About 100,000 Americans undergo ECT each year, while nearly 14.8 million Americans report depression annually [sources: Reti, NIMH]. Although the therapy was once used for a variety of mental disorders, it's now employed almost solely for severe depression or some symptoms of mania [source: NAMI].

While the treatment was always controversial, its popularity waned quite a bit with the introduction (as well as the improvement and variety) of antidepressants and other drugs for mental illnesses on the market. For example, in England between 1985 and 2002, ECT's use more than halved [source: Royal College of Psychiatrists]. In fact, one of the main instances when clinicians turn to ECT is after many different medications have been proven ineffective in treating a patient's severe depression.


Until recently, there's never been proof of how exactly the seizure works to improve mental health. Some theories have to do with the physiology of the brain. It's possible that the seizures can change how blood flows through the brain or the metabolism in certain areas [source: Royal College of Psychiatrists]. Because depression is often treated through chemical means, it's also possible that ECT causes a release (or improved functioning) of certain chemicals in the brain. More research also indicates that ECT can stimulate cell growth and nerve pathways, which might link to improved mood [source: Royal College of Psychiatrists].

A study published in 2012 suggested that an over-communicative brain might be an issue in depression. Shocking the brain might work like turning down a stereo, according to one of the study's authors, allowing a severely depressed patient to think a little more clearly [source: Rettner].

There have also been several studies done with placebo treatments, which point out the effectiveness of ECT. Essentially, the patients receive the exact same treatment -- anesthesia and muscle relaxant included -- and are told they had the shock, but don't. The patients with the actual ECT treatment did recover from their illness much faster. However, some patients with the fake treatment recovered as well, perhaps because of the extra clinical attention [source: Royal College of Psychiatrists]. In severe depression, the treatments do appear to be more effective than medication [source: Royal College of Psychiatrists].

As we talked about earlier, the side effects have also improved quite a bit with modern practice. Headaches are reported, as is muscle pain. There are still memory issues, as well: One-quarter to two-thirds of patients report memory problems after ECT [source: NAMI]. Some patients report having trouble forming memories after the treatment, while others say they have a hard time remembering some events before the therapy. Also, there can be initial confusion after the procedure, which isn't uncommon to coming out of sedation in general.

But that doesn't mean it still doesn't court its fair share of controversy. It's not hard to find groups that oppose the practice. Some are adamantly anti-psychiatry in general, while others claim that long-lasting damage is done to cognition and memory, as well as just being generally ineffective [source: Wilson].


Frequently Asked Questions

How has public perception of ECT changed over the years?
Public perception of ECT has gradually improved with better understanding and advancements in treatment. However, skepticism and controversy remain due to historical depictions and concerns over side effects.
What future advancements in ECT are researchers exploring to minimize side effects?
Researchers are exploring precision targeting of electric currents and individualized treatment protocols to minimize cognitive side effects while maintaining or enhancing ECT's therapeutic effectiveness.

Lots More Information

Author's Note: How Electroconvulsive Therapy Works

I'll admit that I was, um, shocked to learn how well-regarded ECT is in the psychiatric and medical community. Like most people, I didn't realize how far the procedure had come and how beneficial it had proven to a lot of folks. While I think there's a lot to be understood about its effectiveness and how it works, I certainly think that more study and experimentation is warranted.

Related Articles

  • Attkisson, Sharyl. "Shock Therapy: Old treatment, new scrutiny." CBS News. Jan. 31, 2011. (March 14, 2013);lst;1
  • Barnes, Richard. "Information on ECT." Royal College of Psychiatrists. December 2012. (March 14, 2013)
  • "Electroconvulsive Therapy (ECT): Q&A with Sarah Hollingsworth Lisanby, MD." Duke University. March 6, 2012. (March 14, 2013)
  • Encyclopædia Britannica Online Library Edition. "Shock therapy." 2013. (March 14, 2013)
  • Good Morning America. "Kitty Dukakis: Shock therapy saved my life." ABC News. Sept. 18, 2006. (March 14, 2013)
  • Johns Hopkins Medicine. "Electroconvulsive (ECT) Service." Johns Hopkins University. (March 14, 2013)
  • Johns Hopkins Newsletter. "ECT without the Hollywood." John Hopkins University. 2007. (March 14, 2013)
  • Mayo Clinic. "Electroconvulsive therapy." Mayo Clinic. Oct. 25, 2012. (March 14, 2013)
  • National Alliance on Mental Illness. "What is electroconvulsive therapy?" National Alliance on Mental Illness. July 2012. (March 14, 2013)
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  • National Institute of Mental Health. "Brain Stimulation Therapies." National Institute of Health. Nov. 17, 2009. (March 14, 2013)
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  • Payne, Nancy A. and Prudic, Joan. "Electroconvulsive Therapy Part I: A perspective on the evolution and current practice of ECT." Journal of Psychiatric Practice. September 2009. (March 14, 2013)
  • Reti, Irving. "Electroconvulsive Therapy Today." John Hopkins Clinic. (March 22, 2013)
  • Rettner, Rachael. "Depressed brain explained by new electroconvulsive therapy study." Huffington Post. March 19, 2012. (March 14, 2013)
  • United States Food and Drug Administration. "FDA Executive Summary (Meeting to discuss the classification of Electroconvulsive therapy devices.)." United States Food and Drug Administration. January 2011. (March 14, 2013)
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  • Wilson, Duff. "F.D.A. Panel is split on electroshock risks." The New York Times. Jan. 28, 2011. (March 14, 2013)