Brain Scans Show 4 Different Types of Depression

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iStock

Scientists say they’ve found neurological evidence of four different subtypes of depression—a discovery that may someday help doctors select the best treatment for their depressed patients. The research was published in the journal Nature Medicine.

Depression is an exceptionally slippery beast. Unlike ailments located elsewhere in the body, mental illnesses are classified and diagnosed not by concrete physical signs, or biomarkers, but by patients’ behavior. There are a lot of problems with this approach, including the fact that a lot of different illnesses can cause the same symptoms—and that the same illness can cause different symptoms in different people.

What we call “depression” is an experience that likely has many different causes, co-author Conor Liston of Weill Cornell Medical College told Scientific American. “The fact that we lump people together like this has been a big obstacle in understanding the neurobiology of depression.”

Liston and his colleagues analyzed functional magnetic resonance imaging (fMRI) scans from 17 different research sites around the world. They took in scans from 1188 people, about 40 percent of whom had depression, and were able to look closely at an astounding 258 brain regions in each person.

The team had expected to find some differences between the brains of people with depression and without. They found those, but they also found differences within the group of depressed people. Differences in brain activity and connectivity revealed four distinct subtypes among people with depression.

Most excitingly, these brain-activity subtypes matched up with different medical profiles. Patients in subtypes 1 and 2 described feeling more fatigue, while people in subtypes 3 and 4 had trouble feeling pleasure.

The subtypes also responded differently to treatment techniques. People in subtype 1, for example, were more likely to experience relief with transcranial magnetic stimulation (TMS), a non-pharmaceutical method that uses electromagnetic impulses to stimulate a sluggish brain.

More research is needed, but these findings are both heartening and promising, Liston says. Depression “is not just one biological thing.”

[h/t Scientific American]

The (Likely) Reason Men Don't Live as Long as Women

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iStock/fstop123

Owing to long-held habits like drinking, smoking, and warring, men have traditionally come up short when it comes to life expectancy. In 2016, the National Center for Health Statistics released data indicating women in the U.S. could expect to live an average of 81.1 years. Men, 76.1. That's a full five fewer years of enjoying this mortal coil. To pose a scientific question—what gives?

In an essay penned for Nautilus, Richard G. Bribiescas, a professor of anthropology, ecology and evolutionary biology at Yale University, believes that the answer rests outside of the male gender making poor life choices. Biologically, men may look forward to curtailed lifespans because of the hormone testosterone.

Bribiescas argues that, while testosterone provides beneficial boosts in libido, mood, and aggression—all key, in some measure, to both survival and reproduction—there is a biological price paid for the markedly higher levels seen in men than women. Testosterone can affect the body's immunological response, suppressing the immune system and making men more susceptible to illness. The hormone has also been associated with increased cancer risk, including prostate cancer.

Evolution seems to have put up with testosterone because of its impact on reproduction, which is why the male body hasn't come up with a way to dismiss the hormone. But men might not be losing years for much longer. A statistical analysis by Cass Business School in the UK forecasts men and women may both live an average of 87.5 years by 2032. Longevity may improve as a result of less alcohol consumption and smoking, as well as better treatments for heart disease. But that's simply a prediction. It may be that testosterone will continue to be an inherent risk factor for males, one that no lifestyle changes can outpace.

[h/t Nautilus]

Now Ear This: A New App Can Detect a Child's Ear Infection

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iStock.com/Techin24

Generally speaking, using an internet connection to diagnose a medical condition is rarely recommended. But technology is getting better at outpacing skepticism over handheld devices guiding decisions and suggesting treatment relating to health care. The most recent example is an app that promises to identify one of the key symptoms of ear infections in kids.

The Associated Press reports that researchers at the University of Washington are close to finalizing an app that would allow a parent to assess whether or not their child has an ear infection using their phone, some paper, and some soft noises. A small piece of paper is folded into a funnel shape and inserted into the ear canal to focus the app's sounds (which resemble bird chirps) toward the child’s ear. The app measures sound waves bouncing off the eardrum. If pus or fluid is present, the sound waves will be altered, indicating a possible infection. The parent would then receive a text from the app notifying them of the presence of buildup in the middle ear.

The University of Washington tested the efficacy of the app by evaluating roughly 50 patients scheduled to undergo ear surgery at Seattle Children’s Hospital. The app was able to identify fluid in patients' ears about 85 percent of the time. That’s roughly as well as traditional exams, which involve visual identification as well as specialized acoustic devices.

While the system looks promising, not all cases of fluid in the ear are the result of infections or require medical attention. Parents would need to evaluate other symptoms, such as fever, if they intend to use the app to decide whether or not to seek medical attention. It may prove most beneficial in children with persistent fluid accumulation, a condition that needs to be monitored over the course of months when deciding whether a drain tube needs to be placed. Checking for fluid at home would save both time and money compared to repeated visits to a physician.

The app does not yet have Food and Drug Administration (FDA) approval and there is no timetable for when it might be commercially available. If it passes muster, it would join a number of FDA-approved “smart” medical diagnostic tools, including the AliveKor CardiaBand for the Apple Watch, which conducts EKG monitoring for heart irregularities.

[h/t WGRZ]

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