Brain cleanup on aisle 5
You’ve got your local grocery store down. You know the ins and outs; you know where everything is. Last week you did your trip in record time. This week, however, you have to stop at a different store. Same chain, but a different location. You stroll in, confidently walk toward the first aisle for your fruits and veggies, and ... it’s all ice cream. Oops.
Max Pixel
There’s a lot we don’t understand about the brain, including how it remembers familiar environments to avoid confusion. Or why it fails to do so, as with our grocery store example. However, thanks to a study from the University of Arizona, we may have an answer.
For the experiment, a group of participants watched a video tour of three virtual cities. Those cities were very similar, being laid out in basically identical fashion. Stores could be found in the same places, but the identity of those stores varied. Some stores were in all three cities, some were in two, and some were unique. Participants were asked to memorize the layouts, and those who got things more than 80% correct ran through the test again, only this time their brain activity was monitored through MRI.
In general, brain activity was similar for the participants; after all, they were recalling similar environments. However, when asked about stores that appeared in multiple cities, brain activity varied dramatically. This indicated to the researchers that the brain was recalling shared stores as if they were more dissimilar than two completely disparate and unique stores, a concept often known to brain scientists as “repulsion.” It also indicates that the memories regarding shared environments are stored in the prefrontal cortex, not the hippocampus, which typically handles memory.
The researchers plan to apply this information to questions about diseases such as Alzheimer’s, so the next time you get turned around in a weirdly unfamiliar grocery store, just think: “It’s okay, I’m helping to solve a terrible brain disease.”
The real endgame: Friction is the winner
Spoiler alert! If you haven’t seen “Avengers: Infinity War” yet, we’re about to ruin it for you.
Georgia Tech
Dr. Saad Bhamla
For those still with us, here’s the spoiler: Thanos would not have been able to snap his fingers while wearing the Infinity Gauntlet.
Saad Bhamla, PhD, of Georgia Tech University’s school of chemical and biomolecular engineering, had been studying powerful and ultrafast motions in living organisms along with several colleagues before the movie came out in 2018, and when they saw the finger-snapping scene it got them wondering.
Being scientists of course, they had no choice. They got out their high-speed imaging equipment, automated image processing software, and dynamic force sensors and analyzed finger snaps, paying close attention to friction by covering fingers with “different materials, including metallic thimbles to simulate the effects of trying to snap while wearing a metallic gauntlet, much like Thanos,” according to a statement on Eurekalert.
With finger snaps, it’s all about the rotational velocity. The angular acceleration involved is the fastest ever measured in a human, with a professional baseball pitcher’s throwing arm a distant second.
Dr. Bhamla’s reaction to their work explains why scientists are the ones doing science. “When I first saw the data, I jumped out of my chair,” he said in the written statement.
Rotational velocities dropped dramatically when the friction-reducing thimbles were used, so there was no snap. Which means that billions and billions of fictional lives could have been saved if the filmmakers had just talked to the right scientist.
That scientist, clearly, is Dr. Bhamla, who said that “this is the only scientific project in my lab in which we could snap our fingers and get data.”