Single dose of antidepressant changes the brain

September 18, 2014, Cell Press
Credit: Rice University

A single dose of antidepressant is enough to produce dramatic changes in the functional architecture of the human brain. Brain scans taken of people before and after an acute dose of a commonly prescribed SSRI (serotonin reuptake inhibitor) reveal changes in connectivity within three hours, say researchers who report their observations in the Cell Press journal Current Biology on September 18.

"We were not expecting the SSRI to have such a prominent effect on such a short timescale or for the resulting signal to encompass the entire brain," says Julia Sacher of the Max Planck Institute for Human Cognitive and Brain Sciences.

While SSRIs are among the most widely studied and prescribed form of worldwide, it's still not entirely clear how they work. The drugs are believed to change in important ways, but those effects had generally been thought to take place over a period of weeks, not hours.

The new findings show that changes begin to take place right away. Sacher says what they are seeing in medication-free individuals who had never taken antidepressants before may be an early marker of brain reorganization.

Study participants let their minds wander for about 15 minutes in a brain scanner that measures the oxygenation of blood flow in the brain. The researchers characterized three-dimensional images of each individual's brain by measuring the number of connections between small blocks known as voxels (comparable to the pixels in an image) and the change in those connections with a single dose of escitalopram (trade name Lexapro).

Their whole-brain network analysis shows that one dose of the SSRI reduces the level of intrinsic connectivity in most parts of the brain. However, Sacher and her colleagues observed an increase in connectivity within two regions, specifically the cerebellum and thalamus.

The researchers say the new findings represent an essential first step toward clinical studies in patients suffering from depression. They also plan to compare the signature of brains in recovery and those of patients who fail to respond after weeks of SSRI treatment.

Understanding the differences between the brains of individuals who respond to SSRIs and those who don't "could help to better predict who will benefit from this kind of antidepressant versus some other form of therapy," Sacher says. "The hope that we have is that ultimately our work will help to guide better treatment decisions and tailor individualized therapy for patients suffering from depression."

Explore further: Dyslexic readers have disrupted network connections in the brain

More information: Current Biology, Schaefer et al.: "Serotonergic modulation of intrinisic functional connectivity." www.cell.com/current-biology/a … 0960-9822(14)01037-9

Related Stories

Dyslexic readers have disrupted network connections in the brain

August 28, 2014
Dyslexia, the most commonly diagnosed learning disability in the United States, is a neurological reading disability that occurs when the regions of the brain that process written language don't function normally.

Drugs for depression linked with failure of dental implants

September 12, 2014
A team from McGill University has discovered that people who take the most common antidepressants (such as Celexa, Paxil, Lexapro, Prozac, and Zoloft, the Selective Serotonin Reuptake Inhibitors or SSRIs) are twice as likely ...

Compound enhances SSRI antidepressant's effects in mice

June 21, 2013
A synthetic compound is able to turn off "secondary" vacuum cleaners in the brain that take up serotonin, resulting in the "happy" chemical being more plentiful, scientists from the School of Medicine at The University of ...

Antidepressants and self-harm: For those under 24, initial dose matters

May 6, 2014
About a decade after the Food and Drug Administration first warned that antidepressant medications increase the risk of suicidal thoughts and behaviors in children, new research has found that kids and young adults starting ...

A tiny molecule may help battle depression

June 8, 2014
Levels of a small molecule found only in humans and in other primates are lower in the brains of depressed individuals, according to researchers at McGill University and the Douglas Institute. This discovery may hold a key ...

Blood test might predict how well a depressed patient responds to antidepressants

December 15, 2011
Loyola University Medical Center researchers are reporting what could become the first reliable method to predict whether an antidepressant will work on a depressed patient.

Recommended for you

Young children use physics, not previous rewards, to learn about tools

February 23, 2018
Children as young as seven apply basic laws of physics to problem-solving, rather than learning from what has previously been rewarded, suggests new research from the University of Cambridge.

Study: Tinder loving cheaters—dating app facilitates infidelity

February 23, 2018
The popular dating app Tinder is all about helping people form new relationships. But for many college-aged people, it's also helping those in relationships cheat on their romantic partners.

Looking for the origins of schizophrenia

February 23, 2018
Schizophrenia may be related to neurodevelopmental changes, including brain's inability to generate an appropriate vascular system, according to new study resulted from a partnership between the D"Or Institute for Research ...

Color of judo uniform has no effect on winning

February 22, 2018
New research on competitive judo data finds a winning bias for the athlete who is first called, regardless of the colour of their uniform. This unique study, published in Frontiers in Psychology, puts to rest the debate on ...

Antidepressants are more effective than placebo at treating acute depression in adults, concludes study

February 22, 2018
Meta-analysis of 522 trials includes the largest amount of unpublished data to date, and finds that antidepressants are more effective than placebo for short-term treatment of acute depression in adults.

Infants are able to learn abstract rules visually

February 22, 2018
Three-month-old babies cannot sit up or roll over, yet they are already capable of learning patterns from simply looking at the world around them, according to a recent Northwestern University study published in PLOS One.

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.