The Dark Traits of People Who Use Tinder While In Relationships

Headlines in science you won't want to miss
Man on phone in bed

Almost a quarter of Tinder users aren't actually single

Dating apps can be an interesting place to gather data and learn about human behavior. Helen Fisher, a biological anthropologist, has done this with data; this is the eighth year a fascinating report called Singles in America has been released, all about people’s dating habits and preferences.

A new study in Computers in Human Behavior looked at data on Tinder users, and found something a bit darker: They reported that a portion of Tinder users were in committed relationships while they were using the app. The researchers surveyed 1,486 Tinder users, finding that around 22 percent of them were in relationships. And half of those people said that they had met up with someone they connected with on Tinder.


The authors of the study then decided to look at the personality traits and motivations of these non-single Tinder users. There are a group of measurements in psychology alluringly known as the Dark Triad, which gauge Machiavellianism, Narcissism, and Psychopathy. (If you remember your high school social studies, Machiavelli was the guy who said it’s best for a leader to be feared and not loved.)

“These distinct, but related, personality traits are characterized by exploitation, manipulation, a lack of empathy, and emotional coldness, and have received quite some research attention in predicting human behavior in many contexts,” the researchers wrote.

When they looked to see if non-single Tinder users had these dark traits, they found that users did score lower on scales for “Agreeableness” and “Conscientiousness,” and they scored higher on scales for “Neuroticism” and “Psychopathy.” The non-single Tinder users who had lower scores for agreeableness and conscientiousness, and higher scores for neuroticism and psychopathy were more likely to use the app for sex. Having high Narcissism and Machiavellianism traits was associated with using Tinder for an ego boost.

There were limitations to how self-reports were gathered, so future work on Tinder-user motivations and personality traits will have to be more detailed in asking about relationship lengths, and the timings of behaviors, the authors noted.


“Our findings leave me wondering whether dating apps might be a threat to romantic relationships," study author Elisabeth Timmermans told PsyPost. "Of course our findings are too preliminary to make such conclusions, but they already suggest that some people (i.e., with certain personality traits) might be more susceptible to using dating apps for infidelity purposes than others.”

If ketamine is an opioid, should it be used for depression?

Ketamine has been showing great promise in treating depression, and seems like it can act faster than any other drug available. While traditional antidepressants can take weeks to kick in, ketamine sometimes starts working in as little as 40 minutes. But a new study shows that some of those effects could be from activating the brain’s opioid system, which is involved with pain, reward, and also addiction. Previously, it was thought that ketamine worked by interacting only with the brain’s glutamate system, which is involved in memory and learning.

To test what ketamine was doing in the brain, the researchers began a double-blind crossover study of adults with treatment-resistant depression. Some participants got ketamine and a placebo, and others got ketamine and naltrexone, which blocks opioid receptors. “The naltrexone canceled out the antidepressive effects of the ketamine so completely that researchers cut the study short for ethical reasons,” Science Magazine reported.


Researchers are mixed about what this means, NPR reports. Some think that ketamine could prove as addictive as other opioids, and we should proceed with caution when using it for mental health treatments. Study author Carolyn Rodriguez told NPR that the effects on the glutamate system are still important, and the new findings are "the beginning of a conversation" that reveal that “ketamine's mechanism of action is complicated.”

Socially excluded flies' tumors progress more rapidly

A new study in flies found that social interactions might influence the progression of non-communicable diseases, like cancer. Researchers put a fly with a tumor into a group with healthy flies. The other healthy flies socially isolated the sick fly so much, that it might as well have been alone. But when the sick fly was surrounded with other cancerous flies, those flies included it in their social group. In the fly that was excluded from the healthy flies, the tumor progressed more rapidly, and in the fly that was included with its sick peers, the tumor growth slowed.

So how did the healthy flies know that the fly had a tumor at all? Beata Ujvari, an evolutionary biologist and author on the paper, says they’re not sure. They don’t know if the flies could detect the cancer, or if they picked up on the cancerous fly behaving differently than the rest. (Though she says there are some intriguing human cancer studies that show that olfactory, or smell, neurons on fruit fly's antenna can discriminate healthy mammary epithelial cells from different kinds of breast cancer cells.)


However the flies knew, the researchers hypothesize that the isolated fly’s tumor progressed more rapidly because it was under extra stress. “That could potentially take away resources from tumor suppression and/or could cause favorable conditions for tumor growth,” Ujvari says.

The question to ask when it comes to animal studies is, can we directly translate this to humans? Would humans in isolation have diseases that progress faster? Ujvari says that we don’t know for sure, but psycho-social factors like traumatic life events, high levels of depressive symptoms, or low levels of social support, have been related to higher rates of cancers, like breast and colon cancer. In mammals, social isolation has been associated with faster progression of type 2 diabetes, cardiovascular or cerebrovascular disorders, and mammary cancer development, she adds.

“Further experiments on other vertebrate species before we can directly translate the concept to human studies, nevertheless, our study highlights the importance of social support and psycho-social wellbeing in cancer progression and outcomes,” she says.

You can think another body is your own just by looking at it

The rubber hand illusion is a famous body ownership trick where you can fool your mind into thinking that a rubber hand is your own. It goes like this: Your own hand is hidden, and you look at a rubber hand instead. Then, your real hand and the rubber hand are touched or stroked in the same way. Soon, you’ll feel that touch coming from the rubber hand rather than your real one. It’s a neat way to get a sense of how the brain knows where its body is located in space, and what belong to your body and what doesn’t.

A new study, available for preprint on bioRxiv, found that you can achieve this illusion even easier than previously thought: You don’t need the touch element of it. It was believed that the synchronous touching was crucial for creating the body ownership sensation. But researchers from the UK showed that in some people, just visually observing a mannequin body from a first-person perspective could lead to embodiment.


“Can we acquire ownership of a fake body just by looking at it? Yes, we can!” Author Laura Crucianelli tweeted. For more on controlled out-of-body experiences, check out how transferring your consciousness into a robot head could make you less afraid to die.

Why might a person donate a kidney to a complete stranger?

Risking ourselves for others doesn’t make a whole lot of sense, evolutionarily speaking. If we are organisms trying to survive, why would we do something that could hurt our ability to do so?

There’s a theory that altruism is driven by empathy, writes Christian Jarrett in The Psychologist. The more you feel others’ distress, perhaps the more you’ll feel the desire to help. A new study tried to measure the relationship between empathy and helping others, by looking at the brain responses of people who are super altruistic: They donated kidneys to complete strangers.

Researchers at the University of Pennsylvania brought 25 people who donated their kidneys to the lab and compared them to 27 controls. They made everyone experience painful pressure on their thumbs, and also watch a video of someone else going through the same pain.

The kidney donors had more neural overlap when they experienced pain as when they watched others experience pain, compared to controls. This means that they even when they were just watching someone else feel pain, they had similar levels of activity in the brain regions associated to pain as when they were feeling the pain themselves. They also showed similar brain activity when anticipating a stranger’s pain, as when they were anticipating their own pain.


“The present findings directly link objectively measured empathy and altruism,” the authors wrote, though they noted that their findings need to be replicated in less extreme altruists in the future.

More intriguing health reads

Apparently, some gynecologists refer to vaginas as “self-cleaning ovens.”

I’ve never been so jealous of someone sealed into an 11-by-11.5-foot room. Belluz learns about her own metabolism, and busts some well-trodden metabolism myths along the way.

“There are two kinds of people in the world: people who think there are two kinds of people in the world and people who don’t.”

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