How depression affects the brain

Watch what depression does to the brain

This video explores the neurobiology of depression and why unraveling the complexities of this disease and its etiology will potentially improve treatments. Effective depression treatment, as this video highlights, can eventually make a depressed brain look like a healthy one on brain scans.

These areas of the brain are hard-hit in depression—but the changes are reversible

Depressed brains can have certain characteristic changes, including an overactive amygdala, reduced hippocampus size, and changes to the thalamus and neuromodulating chemicals in the brain.

See how antidepressants were discovered

The decadeslong journey to the three major types of antidepressants began with medications designed to treat other maladies. Watch to learn more about how attempts to treat tuberculosis and blood pressure disorders led to new insights about neural chemistry and mood.

JJ Schildkraut theorized depression is linked to brain chemical imbalances—in 1965

Schildkraut was one of the first to put forward this idea, which stemmed from lab animal research. A decade later, researchers published the first landmark paper on fluoxetine—better known by trade name Prozac—which increases serotonin levels in the brain.

Antidepressants alone may fail to help an estimated one-third to one-half of depressed patients

There are three major categories of antidepressants—tricyclic antidepressants, monoamine oxidate inhibitors, and selective serotonin reuptake inhibitors. This podcast notes these first-line depression drugs are not effective for many patients and may also come with concerning side effects. Other therapeutic approaches—either in combination with medication or as an alternative—include therapy, meditation, and consistent exercise.

How four types of psychedelics affect the brain

Brain imaging shows that ayahuasca, MDMA, DMT, and psilocybin profoundly affect neural activity, giving rise to higher states of introspection and consciousness. This article details exactly how each of these drugs physically affects the brain and what that means for mental health treatment. Some of these drugs quiet the brain or trigger the release of neurochemicals associated with mood regulation and learning.

Stress and the brain

While an acute stress response is a normal bodily function, the effects of chronic stress can be extremely damaging to the human body. This is particularly true with regard to the brain. This article explores the effects of stress on the human brain, including how chronic stress may lead to psychological conditions such as depression and memory loss.

Exercise releases chemicals that enhance cognitive function

Neurotransmitters like dopamine, serotonin, and norepinephrine, along with increased brain-derived neurotrophic factor levels, enhance a wide range of brain functions. New research demonstrates a direct link between movement and numerous cognitive benefits, including memory, learning, and stress resilience.

What happens to your brain when you burn out?

You've probably heard of burnout, also known as the feeling of exhaustion that happens after a long period of being overwhelmed or stressed. It's often associated with work and careers, but other parts of life, like parenting, can cause burnout, too. Scientists are figuring out what happens, biochemically speaking, in the brain when burnout hits—and spoiler alert, it includes a neurotransmitter called glutamate. Watch this video to learn more.

What sleep loss does to the brain

Proteins in the brain perform various critical functions, such as helping neurotransmitters function or enabling electrical activity in the organ. These proteins must fold in specific ways to perform their duties, similar to paper airplanes. Sleep deprivation contributes to the gathering of misfolded proteins that aren't shaped correctly for their roles and so accumulate in undesired spaces, such as in the gaps between neurons.

Alzheimer's can lead to brain shrinkage, with an average of around 2% of volume reduction per year

The depression paradox refers to a lack of energy to take action to help alleviate it

Activities like exercise, even at low levels, have been shown to alleviate some of depression's symptoms for some people. However, depression saps energy levels, making it particularly difficult to motivate oneself to take helpful action.

"Plaques" and "tangles" are top potential causes of Alzheimer's—but questions remain

The exact causes of Alzheimer's—and how to treat it—continue to be the subject of intense research. Two leading factors are amyloid beta plaques and tau protein tangles, which effectively pile up in the brain and interfere with neurons and cause cell death, which manifests as memory loss and other symptoms.

Listen to how the gut microbiome influences your emotions

The gut-microbiome connection may involve the enteric nervous system, a collection of hundreds of millions of neurons throughout the gut that transmit signals up the vagus nerve to the brain.

Inflammation appears to cause specific symptoms of depression

A large analysis of existing studies published in 2021 found that systemic inflammation is associated with fatigue, appetite changes, and sleep disruption, rather than some of depression's broader symptoms including hopelessness about the future, or feeling fearful. This may suggest that inflammation influences specific symptoms of the condition, rather than the disease as a whole.

Anesthetics slow brain activity by promoting inhibitory neurotransmitters

Drugs like propofol and isoflurane increase activity at the GABA receptor, which opens chloride channels. These ions enter neurons and hyperpolarize them, making them less likely to fire. Dexmedetomidine instead blocks norepinephrine receptors in the brainstem to sedate patients.

Depression is much more than sadness—and isn't fleeting

The American Psychiatric Association's DSM-5—used for defining diagnoses—says a person must be experiencing five or more symptoms of depression most of the day over at least two weeks. Research indicates older people are less likely than younger people to meet that depression benchmark, though this article says they still often have at least several of the depression symptoms.

Forcing a smile can actually make you feel slightly better

Activating your smile muscles—in this case, with electrical muscle stimulation that forces the corners of the mouth upward—makes people feel more positive, according to recent research. It won't cure depression, but it can have a small effect. Earlier faux smile research using different nonelectrical techniques had similar results, collectively suggesting that a smile may help brighten your day—even though the mechanisms for the happier result remain unclear.

Yoga is believed to improve mental health, but studies are not definitive

Many think that yoga's combination of stretching, focused breathing, and contemplation help treat depression and anxiety, but the data has often relied on small, homogenous sample sizes.

Addiction develops when the pleasure circuits in the brain get overwhelmed

Normal pleasure circuits become overwhelmed by addictive substances, triggering dopamine floods many times stronger than those induced by everyday reward experiences. The understanding of addiction as a brain disease has led to treatments pairing medication and counseling.

How menopause affects mental health

Menopause, a natural biological process, occurs in three stages: perimenopause (hormone fluctuations), menopause (end of menstrual cycles), and postmenopause (12 months without menstruation). Hormonal shifts during this time can affect neurotransmitters, increasing the risk of mood disorders.

Could all mental health disorders have a unifying 'p-factor'?

Some researchers have argued in the past couple decades that all mental health disorders may have a unifying dimension—a theoretical "p-factor" that is common across mental illness, but life experiences and behaviors influence if and how illness manifests. Proponents point to similarities across different disorders, while detractors argue that such connections are largely exaggerated.

SAD disrupts melatonin secretion, producing it longer in the morning

The hormone is secreted from the pineal gland in the brain and is key to the timing of sleep. However, the substance does not generate sleep itself. With seasonal affective disorder, the body misperceives the photoperiod—the time with light—and the cycle of sleeping and waking gets off-phase, leading to issues with circadian rhythms.

Scientists identify hundreds of genes responsible for OCD

Researchers analyzed the DNA of more than 53,000 people with OCD and identified 30 areas in the genome linked to the disease, containing 249 genes of interest. Of those, several were linked to other brain disorders, paving the way for genetic treatments of various mental illnesses.

Hippocratic doctors treated severe mental illness with the poisonous plant hellebore

Since symptoms like hallucinations were believed be due to an imbalance of black bile, yellow bile, blood, and phlegm, the treatment at the time was to bring those humors back into balance. That meant standard treatments could include bleeding a patient or using substances like hellebore to induce vomiting or diarrhea.

How the body produces its own opioids

Opioids act on the body's own opioid receptor system. The endogenous opioid system comprises four molecule receptor types found throughout the body. When activated, these receptor types trigger the release of dopamine and suppression of noradrenaline, neurotransmitters, respectively, associated with reward and alertness. This opioid system helps regulate emotions, and its disruption is linked to neuropsychiatric conditions, including depression, PTSD, and Alzheimer's disease.

In recent years a child anxiety expert has created and tested a novel phobia and anxiety treatment approach for children, focused on changing how parents respond to the fears.

Recent research found that the brain doesn't seem to massively rewire following amputation—upending earlier beliefs about the cause of phantom limb pain.

Studies suggest when you sleep is as important as how much you get, and syncing with your circadian rhythms may lead to less fatigue and improved long-term health outcomes

While atoms are normally made of protons, neutrons, and electrons, exotic ones have been built with antimatter—alternate versions of normal matter that live for fractions of a second and are about a billion times as rare.

Listen to an in-depth conversation on the links between Parkinson's disease and herbicide exposure and the challenging pace of scientific investigation.

The hormonal disorder PCOS was renamed PMOS in 2026, a move designed to improve care and research by shifting the focus to the hormonal causes of this condition that affects 1 in 8 women.

As of 2025, the most cited papers in science include a review of graphene, methods to improve image recognition, streamlining electron density calculations, and optimizing protein studies.

Explore an interactive map built from more than 100,000 survey responses on where people find joy in their lives

Hookworm infection, though risky, may help fight certain autoimmune conditions by tamping down the immune system's inflammatory response.

Learn how your body is, scientifically, like a firework with its own slow, controlled burn.

Coral reefs get their colors from zooxanthellae—microorganisms that line corals' digestive tracts and provide them with sugars in exchange for a home within this protective tissue.

Three Ebola species are responsible for most large outbreaks of the disease, yet the only approved Ebola vaccine is known to work against just one of them.

Watch how deep-sea mining equipment collects and processes polymetallic nodules—metal-rich, potato-shaped rocks—from the ocean floor and creates environmentally damaging plumes of sediments.

Volcanic activity may have triggered the Black Death by spewing gases that led to crop failures in Europe, thus forcing the import of grain ships with plague-infested fleas.

A Yale student wrote a profound essay about the consulting industry's influence on elite college students that was published in a book of her writing after she died in a post-graduation car accident.

Netflix profits when you're not watching, and its movies are designed that way—read a detail-rich critical essay exposing lesser-known Netflix takes

In 1939, baseball star Lou Gehrig delivered his inspirational 'Luckiest Man' speech after retiring due to the health condition that now bears his name.

The price of gas is a composite made up of several different factors, with the federal gas tax making up less than 20% of what drivers pay at the pump.

Some renewable energy sources may weaken the resiliency of electric grids by removing outage buffers provided by coal- and natural gas-fired plants, which provide the system with more time to find a new power source if a plant goes down.

While the sun's gravity keeps the planets in orbit, their gravity also pulls on the sun, causing it and everything else in the solar system to orbit around a mutual balance point called the barycenter—the true center of the solar system.

A researcher recently discovered an interview from 1967 between groundbreaking journalist Joan Didion and the Grateful Dead, years before the band became an institution.

Clever Hans was a 1900s horse that was believed to be able to solve math equations, tell time, and read and comprehend German, until a psychology student discovered how he got his answers.

While El Niño moves warm Pacific Ocean waters east along the equator, La Niña moves them west, shifting where rainfall will become more common for months.

Budweiser stores yeast derived from the original 1800s strain in a secret bunker, which only the Head of Yeast Management can access—not even the CEO