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 Unkindest Cut: The Chainsaw Was Invented to Assist With Difficult Childbirths

viafilms/iStock via Getty Images
viafilms/iStock via Getty Images

There’s always a price to be paid for innovation. Usually that amounts to some sleepless nights and lots of trial and error. But sometimes it means attempting to deliver babies with a chainsaw.

This dark chapter in agricultural history comes from Popular Science, which recently detailed how the motorized cutting tool populating Home Depot shelves came to be. In the 18th century, two Scottish surgeons named John Aitken and James Jeffray devised a solution they could employ when faced with difficult childbirths. Rather than use a knife to widen the pelvic area by slicing through cartilage and bone to extricate a stuck baby, the two developed a chainsaw to make cutting easier.

While this sounds ghastly, the doctors were actually trying to lessen the agony endured by women who needed their pelvic bone separated. The knife took a long time, while their device—a modified knife with serrated “teeth” on a chain—could cut through bone and tissue more quickly.

If circumstances warranted it, the doctor would grab the saw, which had a handle on both ends, and wrap the chain around the pelvic bone, pulling each handle so the chain would cut into the bone. Later, the device was outfitted with a hand crank. Thanks to this innovation, difficult births could be described as merely agonizing as opposed to extended torture.

The procedure was dubbed a symphysiotomy and remained in use in the medical field as surgeons noticed how efficiently it could work in other circumstances, like amputations. It lasted through much of the 19th century as part of a surgical toolbox until C-sections grew in popularity. In the 20th century, the principle was commandeered for less disturbing purposes like logging, with two-person saws weighing more than 100 pounds each. By the 1950s, those gave way to lighter models.

For all its discomfiting history, at least the chainsaw proved to be useful—which isn't something that can be said for all inventions purporting to aid in childbirth. In 1965, George and Charlotte Blonsky patented a device that acted as a human turntable, spinning so quickly it might induce the patient (or victim) into delivering their baby via centrifugal force.

[h/t Popular Science]

Kane Tanaka, World’s Oldest Living Person, Just Celebrated Her 117th Birthday

Ruletka, iStock via Getty Images
Ruletka, iStock via Getty Images

Less than a year after being named oldest living person in the world, Kane Tanaka has reached a new milestone. As Reuters reports, Tanaka celebrated her 117th birthday on January 2, 2020, extending the Guinness World Record-winning streak she set in March 2019.

Kane—the seventh of eight siblings—was born on January 2, 1903 in Fukuoka, Japan. She married Hideo Tanaka in 1922, and the couple had five children. Today, she is a grandmother to five and a great-grandmother to eight.

Tanaka celebrated her birthday at the Fukuoka nursing home where she resides, surrounded by friends and family. After taking a bite of her birthday cake, she reportedly said, “Tasty, I want some more." On a typical day, Tanaka spends her time studying math, practicing calligraphy, and beating the nursing home staff at board games.

The 117 club is an exclusive group only a handful of women has entered in recent history. In the last few years, Emma Morano of Italy, Violet Mosse Brown of Jamaica, and Nabi Tajima and Chiyo Miyako of Japan all reached age 117 and were each the oldest person alive for a brief period. If Tanaka celebrates another birthday next year, she will be the first person since the 1990s to live to 118.

[h/t Reuters]

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