Big ideas.
Once a week.
Subscribe to our weekly newsletter.
How does sex alter the brain?
Sex alters the brain in a variety of interesting ways.

Many of us are aware of the impact sex has on our health. It can burn calories, help us sleep better, makes us less hungry, and even calibrates our metabolism. All of these benefits, and yet millennials are having less sex than generations past. While most people are aware of the health benefits, few know how it affects the brain. Turns out, it alters our thinking organ in a myriad of ways.
Sex is a complex process with many neurological networks involved. This includes the regions associated with emotion, pain, and especially the reward circuit. When we’re being stimulated in a sexual way, a host of biochemicals such as dopamine, endorphins, oxytocin, and vasopressin flood our system and alter our neurochemistry.
This hormonal cocktail’s release is directed by the hypothalamus, a small area at the center of the brain that’s involved with a lot of biological functions, including regulating blood pressure, sleep cycles, the sex drive, childbirth, thirst and appetite, and even the production of digestive fluids.

Let’s face it: unless you're gifted with the good looks of Brad Pitt, it isn’t easy to find a partner. The whole reason we’re driven to take part in sex in the first place is, we get a big heaping dose of dopamine out of an orgasm. Sometimes called the “reward molecule,” dopamine is also released when we feel a sense of accomplishment, eat a rich dessert, rock out to our favorite song, win a monetary reward, or partake in drugs or alcohol (including nicotine and caffeine). This is why sex can become a full-blown addiction. Those who’ve had an orgasm also have higher levels of prolactin, a hormone thought to aid sleep, which may be why many of us doze off after an erotic romp.
Pleasurable experiences release dopamine in our brains and the more pleasurable the experience, the more dopamine is released. Credit: Getty Images.
Sex also releases endorphins--the body’s natural painkillers. Some studies have shown that intercourse can relieve a headache, despite being the classic excuse to abstain. Sex can even relieve the dreaded cluster headache, one study shows. Vasopressin and oxytocin meanwhile, give us feelings of arousal, emotional connection, intimacy, and even attachment to our partner. Oxytocin is known as the “calm and cuddle” hormone. This is the same biochemical that bonds mother to child through breastfeeding. It’s also thought to offset cortisol—the stress hormone.
In a 2003 Dutch study, researchers used a positron-emission tomography (PET) scan on male participants while their female partners sexually stimulated them, until orgasm. Scientists specifically zeroed in on the actions of the brain during orgasm. They found that blood flow to the cerebellum increased significantly. This region is known to process emotions. Meanwhile, the lateral orbitofrontal cortex—known as the center of logical reasoning, shuts down. But don’t worry fellas! This happens to the ladies, too.

In a 2005 study, the same Dutch team used a PET scan to monitor male participants once again, while they were being given pleasure by their partners. Here, researchers looked at the men’s brains from the time of arousal until orgasm. They found that when the penis became erect, blood flow increases to two important areas in the right hemisphere, the posterior insula and the somatosensory cortex. The right amygdala, however, saw a decrease in blood flow.
The insula processes feelings of warmth but also pain. While the somatosensory cortex is the area of the brain where pain is encoded. In the amygdala, emotions are created and regulated. It’s believed that the amygdala is dialed down so as to decrease anxiety and fear during arousal stage, up until orgasm.
Rutgers University researchers in one study found that women’s brains are slightly different during sex. Credit: Getty Images.
Surprisingly, reactions within male and female brains aren’t that different, according to a 2017 Rutgers University study. Here, 10 female participants either sexually stimulated themselves or were stimulated by their partner, while strapped into a fMRI. At the time of orgasm, in addition to the aforementioned parts of the brain, they also had heightened activity in the cingulate gyrus. This region helps to sense pain and process emotions. Could this mean that sex is a more emotional process for women than men? Only future studies can tell us for sure.
In the past, it’s been assumed that parts of the brain “shut down” when we orgasm. It can certainly feel that way. We melt into the moment and our consciousness seems to connect to something larger, something beyond ourselves. These studies have found however that nothing could be further from the truth. Rather than deactivating, the brain actually rises in activity as it approaches orgasm, peaking at climax, and settling down again in the afterglow.
To learn more about what happens to you biologically during sex, watch this:
How tiny bioelectronic implants may someday replace pharmaceutical drugs
Scientists are using bioelectronic medicine to treat inflammatory diseases, an approach that capitalizes on the ancient "hardwiring" of the nervous system.
Left: The vagus nerve, the body's longest cranial nerve. Right: Vagus nerve stimulation implant by SetPoint Medical.
- Bioelectronic medicine is an emerging field that focuses on manipulating the nervous system to treat diseases.
- Clinical studies show that using electronic devices to stimulate the vagus nerve is effective at treating inflammatory diseases like rheumatoid arthritis.
- Although it's not yet approved by the US Food and Drug Administration, vagus nerve stimulation may also prove effective at treating other diseases like cancer, diabetes and depression.
The nervous system’s ancient reflexes
<p>You accidentally place your hand on a hot stove. Almost instantaneously, your hand withdraws.</p><p>What triggered your hand to move? The answer is <em>not</em> that you consciously decided the stove was hot and you should move your hand. Rather, it was a reflex: Skin receptors on your hand sent nerve impulses to the spinal cord, which ultimately sent back motor neurons that caused your hand to move away. This all occurred before your "conscious brain" realized what happened.</p><p>Similarly, the nervous system has reflexes that protect individual cells in the body.</p><p>"The nervous system evolved because we need to respond to stimuli in the environment," said Dr. Tracey. "Neural signals don't come from the brain down first. Instead, when something happens in the environment, our peripheral nervous system senses it and sends a signal to the central nervous system, which comprises the brain and spinal cord. And then the nervous system responds to correct the problem."</p><p>So, what if scientists could "hack" into the nervous system, manipulating the electrical activity in the nervous system to control molecular processes and produce desirable outcomes? That's the chief goal of bioelectronic medicine.</p><p>"There are billions of neurons in the body that interact with almost every cell in the body, and at each of those nerve endings, molecular signals control molecular mechanisms that can be defined and mapped, and potentially put under control," Dr. Tracey said in a <a href="https://www.youtube.com/watch?v=AJH9KsMKi5M" target="_blank">TED Talk</a>.</p><p>"Many of these mechanisms are also involved in important diseases, like cancer, Alzheimer's, diabetes, hypertension and shock. It's very plausible that finding neural signals to control those mechanisms will hold promises for devices replacing some of today's medication for those diseases."</p><p>How can scientists hack the nervous system? For years, researchers in the field of bioelectronic medicine have zeroed in on the longest cranial nerve in the body: the vagus nerve.</p>The vagus nerve
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTYyOTM5OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY0NTIwNzk0NX0.UCy-3UNpomb3DQZMhyOw_SQG4ThwACXW_rMnc9mLAe8/img.jpg?width=1245&coordinates=0%2C0%2C0%2C0&height=700" id="09add" class="rm-shortcode" data-rm-shortcode-id="f38dbfbbfe470ad85a3b023dd5083557" data-rm-shortcode-name="rebelmouse-image" data-width="1245" data-height="700" />Electrical signals, seen here in a synapse, travel along the vagus nerve to trigger an inflammatory response.
Credit: Adobe Stock via solvod
<p>The vagus nerve ("vagus" meaning "wandering" in Latin) comprises two nerve branches that stretch from the brainstem down to the chest and abdomen, where nerve fibers connect to organs. Electrical signals constantly travel up and down the vagus nerve, facilitating communication between the brain and other parts of the body.</p><p>One aspect of this back-and-forth communication is inflammation. When the immune system detects injury or attack, it automatically triggers an inflammatory response, which helps heal injuries and fend off invaders. But when not deployed properly, inflammation can become excessive, exacerbating the original problem and potentially contributing to diseases.</p><p>In 2002, Dr. Tracey and his colleagues discovered that the nervous system plays a key role in monitoring and modifying inflammation. This occurs through a process called the <a href="https://www.nature.com/articles/nature01321" target="_blank" rel="noopener noreferrer">inflammatory reflex</a>. In simple terms, it works like this: When the nervous system detects inflammatory stimuli, it reflexively (and subconsciously) deploys electrical signals through the vagus nerve that trigger anti-inflammatory molecular processes.</p><p>In rodent experiments, Dr. Tracey and his colleagues observed that electrical signals traveling through the vagus nerve control TNF, a protein that, in excess, causes inflammation. These electrical signals travel through the vagus nerve to the spleen. There, electrical signals are converted to chemical signals, triggering a molecular process that ultimately makes TNF, which exacerbates conditions like rheumatoid arthritis.</p><p>The incredible chain reaction of the inflammatory reflex was observed by Dr. Tracey and his colleagues in greater detail through rodent experiments. When inflammatory stimuli are detected, the nervous system sends electrical signals that travel through the vagus nerve to the spleen. There, the electrical signals are converted to chemical signals, which trigger the spleen to create a white blood cell called a T cell, which then creates a neurotransmitter called acetylcholine. The acetylcholine interacts with macrophages, which are a specific type of white blood cell that creates TNF, a protein that, in excess, causes inflammation. At that point, the acetylcholine triggers the macrophages to stop overproducing TNF – or inflammation.</p><p>Experiments showed that when a specific part of the body is inflamed, specific fibers within the vagus nerve start firing. Dr. Tracey and his colleagues were able to map these relationships. More importantly, they were able to stimulate specific parts of the vagus nerve to "shut off" inflammation.</p><p>What's more, clinical trials show that vagus nerve stimulation not only "shuts off" inflammation, but also triggers the production of cells that promote healing.</p><p>"In animal experiments, we understand how this works," Dr. Tracey said. "And now we have clinical trials showing that the human response is what's predicted by the lab experiments. Many scientific thresholds have been crossed in the clinic and the lab. We're literally at the point of regulatory steps and stages, and then marketing and distribution before this idea takes off."<br></p>The future of bioelectronic medicine
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8yNTYxMDYxMy9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzNjQwOTExNH0.uBY1TnEs_kv9Dal7zmA_i9L7T0wnIuf9gGtdRXcNNxo/img.jpg?width=980" id="8b5b2" class="rm-shortcode" data-rm-shortcode-id="c005e615e5f23c2817483862354d2cc4" data-rm-shortcode-name="rebelmouse-image" data-width="2000" data-height="1125" />Vagus nerve stimulation can already treat Crohn's disease and other inflammatory diseases. In the future, it may also be used to treat cancer, diabetes, and depression.
Credit: Adobe Stock via Maridav
<p>Vagus nerve stimulation is currently awaiting approval by the US Food and Drug Administration, but so far, it's proven safe and effective in clinical trials on humans. Dr. Tracey said vagus nerve stimulation could become a common treatment for a wide range of diseases, including cancer, Alzheimer's, diabetes, hypertension, shock, depression and diabetes.</p><p>"To the extent that inflammation is the problem in the disease, then stopping inflammation or suppressing the inflammation with vagus nerve stimulation or bioelectronic approaches will be beneficial and therapeutic," he said.</p><p>Receiving vagus nerve stimulation would require having an electronic device, about the size of lima bean, surgically implanted in your neck during a 30-minute procedure. A couple of weeks later, you'd visit, say, your rheumatologist, who would activate the device and determine the right dosage. The stimulation would take a few minutes each day, and it'd likely be unnoticeable.</p><p>But the most revolutionary aspect of bioelectronic medicine, according to Dr. Tracey, is that approaches like vagus nerve stimulation wouldn't come with harmful and potentially deadly side effects, as many pharmaceutical drugs currently do.</p><p>"A device on a nerve is not going to have systemic side effects on the body like taking a steroid does," Dr. Tracey said. "It's a powerful concept that, frankly, scientists are quite accepting of—it's actually quite amazing. But the idea of adopting this into practice is going to take another 10 or 20 years, because it's hard for physicians, who've spent their lives writing prescriptions for pills or injections, that a computer chip can replace the drug."</p><p>But patients could also play a role in advancing bioelectronic medicine.</p><p>"There's a huge demand in this patient cohort for something better than they're taking now," Dr. Tracey said. "Patients don't want to take a drug with a black-box warning, costs $100,000 a year and works half the time."</p><p>Michael Dowling, president and CEO of Northwell Health, elaborated:</p><p>"Why would patients pursue a drug regimen when they could opt for a few electronic pulses? Is it possible that treatments like this, pulses through electronic devices, could replace some drugs in the coming years as preferred treatments? Tracey believes it is, and that is perhaps why the pharmaceutical industry closely follows his work."</p><p>Over the long term, bioelectronic approaches are unlikely to completely replace pharmaceutical drugs, but they could replace many, or at least be used as supplemental treatments.</p><p>Dr. Tracey is optimistic about the future of the field.</p><p>"It's going to spawn a huge new industry that will rival the pharmaceutical industry in the next 50 years," he said. "This is no longer just a startup industry. [...] It's going to be very interesting to see the explosive growth that's going to occur."</p>Japan finds a huge cache of scarce rare-earth minerals
Japan looks to replace China as the primary source of critical metals
- Enough rare earth minerals have been found off Japan to last centuries
- Rare earths are important materials for green technology, as well as medicine and manufacturing
- Where would we be without all of our rare-earth magnets?
What are the rare earth elements?
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA2MTM0Ni9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTYzODExMjMyMn0.owchAgxSBwji5IofgwKtueKSbHNyjPfT7hTJrHpTi98/img.jpg?width=980" id="fd315" class="rm-shortcode" data-rm-shortcode-id="d8ed70e3d0b67b9cbe78414ffd02c43e" data-rm-shortcode-name="rebelmouse-image" />(julie deshaies/Shutterstock)
<p>The rare earth metals can be mostly found in the second row from the bottom in the Table of Elements. According to the <a href="http://www.rareearthtechalliance.com/What-are-Rare-Earths" target="_blank"><u>Rare Earth Technology Alliance</u></a>, due to the "unique magnetic, luminescent, and electrochemical properties, these elements help make many technologies perform with reduced weight, reduced emissions, and energy consumption; or give them greater efficiency, performance, miniaturization, speed, durability, and thermal stability."</p><p>In order of atomic number, the rare earths are:</p> <ul> <li>Scandium or Sc (21) — This is used in TVs and energy-saving lamps.</li> <li>Yttrium or Y (39) — Yttrium is important in the medical world, used in cancer drugs, rheumatoid arthritis medications, and surgical supplies. It's also used in superconductors and lasers.</li> <li>Lanthanum or La (57) — Lanthanum finds use in camera/telescope lenses, special optical glasses, and infrared absorbing glass.</li> <li>Cerium or Ce (58) — Cerium is found in catalytic converters, and is used for precision glass-polishing. It's also found in alloys, magnets, electrodes, and carbon-arc lighting. </li> <li>Praseodymium or Pr (59) — This is used in magnets and high-strength metals.</li> <li>Neodymium or Nd (60) — Many of the magnets around you have neodymium in them: speakers and headphones, microphones, computer storage, and magnets in your car. It's also found in high-powered industrial and military lasers. The mineral is especially important for green tech. Each <a href="https://www.reuters.com/article/us-mining-toyota/as-hybrid-cars-gobble-rare-metals-shortage-looms-idUSTRE57U02B20090831" target="_blank"><u>Prius</u></a> motor, for example, requires 2.2 lbs of neodymium, and its battery another 22-33 lbs. <a href="https://pubs.usgs.gov/sir/2011/5036/sir2011-5036.pdf" target="_blank"><u>Wind turbine batteries</u></a> require 450 lbs of neodymium per watt. </li> <li>Promethium or Pm (61) — This is used in pacemakers, watches, and research.</li> <li>Samarium or Sm (62) — This mineral is used in magnets in addition to intravenous cancer radiation treatments and nuclear reactor control rods.</li> <li>Europium or Eu (63) — Europium is used in color displays and compact fluorescent light bulbs.</li> <li>Gadolinium or Gd (64) — It's important for nuclear reactor shielding, cancer radiation treatments, as well as x-ray and bone-density diagnostic equipment.</li> <li>Terbium or Tb (65) — Terbium has similar uses to Europium, though it's also soft and thus possesses unique shaping capabilities .</li> <li>Dysprosium or Dy (66) — This is added to other rare-earth magnets to help them work at high temperatures. It's used for computer storage, in nuclear reactors, and in energy-efficient vehicles.</li> <li>Holmium or Ho (67) — Holmium is used in nuclear control rods, microwaves, and magnetic flux concentrators.</li> <li>Erbium or Er (68) — This is used in fiber-optic communication networks and lasers.</li> <li>Thulium or Tm (69) — Thulium is another laser rare earth.</li> <li>Ytterbium or Yb (70) — This mineral is used in cancer treatments, in stainless steel, and in seismic detection devices.</li> <li>Lutetium or Lu (71) — Lutetium can target certain cancers, and is used in petroleum refining and positron emission tomography.</li></ul>Where Japan found is rare earths
<img type="lazy-image" data-runner-src="https://assets.rebelmouse.io/eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJpbWFnZSI6Imh0dHBzOi8vYXNzZXRzLnJibC5tcy8xOTA2MTM0OC9vcmlnaW4uanBnIiwiZXhwaXJlc19hdCI6MTY1MTA0NzUxNn0.N3t_iKf6lnnoJ6yVUtl8-wNZICEG2ZxyPzm9ZdE99ks/img.jpg?width=980" id="021b7" class="rm-shortcode" data-rm-shortcode-id="d9dd843fde547a0b69f8798aca18a706" data-rm-shortcode-name="rebelmouse-image" />Minimatori Torishima Island
(Chief Master Sergeant Don Sutherland, U.S. Air Force)
<p>Japan located the rare earths about 1,850 kilometers off the shore of <a href="https://en.wikipedia.org/wiki/Minami-Tori-shima" target="_blank"><u>Minamitori Island</u></a>. Engineers located the minerals in 10-meter-deep cores taken from sea floor sediment. Mapping the cores revealed and area of approximately 2,500 square kilometers containing rare earths.</p><p>Japan's engineers estimate there's 16 million tons of rare earths down there. That's <a href="https://minerals.usgs.gov/minerals/pubs/historical-statistics/ds140-raree.xlsx" target="_blank"><u>five times</u></a> the amount of the rare earth elements ever mined since 1900. According to <a href="https://www.businessinsider.com.au/rare-earth-minerals-found-in-japan-2018-4?r=US&IR=T" target="_blank"><u>Business Insider</u></a>, there's "enough yttrium to meet the global demand for 780 years, dysprosium for 730 years, europium for 620 years, and terbium for 420 years."</p><p>The bad news, of course, is that Japan has to figure out how to extract the minerals from 6-12 feet under the seabed four miles beneath the ocean surface — that's the <a href="https://www.nature.com/articles/s41598-018-23948-5" target="_blank"><u>next step</u></a> for the country's engineers. The good news is that the location sits squarely within Japan's Exclusive Economic Zone, so their rights to the lucrative discovery will be undisputed.</p>Physicist creates AI algorithm that may prove reality is a simulation
A physicist creates an AI algorithm that predicts natural events and may prove the simulation hypothesis.
Pixellated head simulation.
- Princeton physicist Hong Qin creates an AI algorithm that can predict planetary orbits.
- The scientist partially based his work on the hypothesis which believes reality is a simulation.
- The algorithm is being adapted to predict behavior of plasma and can be used on other natural phenomena.
Physicist Hong Qin with images of planetary orbits and computer code.
Credit: Elle Starkman
Are we living in a simulation? | Bill Nye, Joscha Bach, Donald Hoffman | Big Think
<span style="display:block;position:relative;padding-top:56.25%;" class="rm-shortcode" data-rm-shortcode-id="4dbe18924f2f42eef5669e67f405b52e"><iframe type="lazy-iframe" data-runner-src="https://www.youtube.com/embed/KDcNVZjaNSU?rel=0" width="100%" height="auto" frameborder="0" scrolling="no" style="position:absolute;top:0;left:0;width:100%;height:100%;"></iframe></span>Fight or flight? Why some people flee and others stand their ground
How different people react to threats of violence.
Eight women at the forefront of the world’s COVID-19 response
Beyond making up 70% of the world's health workers, women researchers have been at the cutting edge of coronavirus research.
