Fight-Or-Flight Chemical Helps Shift the Brain From Subdued to Alert

    Star-shaped brain cells may help control brain’s focus

    A new study from The Johns Hopkins University shows that the brain cells surrounding a mouse’s neurons do much more than fill space. According to the researchers, the cells, called astrocytes because of their star-shaped appearance, can monitor and respond to nearby neural activity, but only after being activated by the fight-or-flight chemical norepinephrine. Because astrocytes can alter the activity of neurons, the findings suggest that astrocytes may help control the brain’s ability to focus.

    The study involved observing the cells in the brains of living, active mice over long periods of time. A combination of genetically engineered mice and advanced microscopy allowed the researchers to visualize the activity of astrocyte networks in different regions of the brain to learn how these abundant supporting cells are controlled.

    The scientists monitored astrocytes in the area of the brain responsible for controlling movement and saw that the cells often increased their activity as the mice walked on treadmills — but not always, and sometimes astrocytes became active when the animals were not moving. This lack of consistency suggested to the researchers that the astrocytes were not responding to nearby neurons, as had been thought.

    Similarly, astrocytes in the vision processing area of the brain did not necessarily become active when the mice were stimulated with light, but they were sometimes active, even in the dark. The team solved both mysteries when they tested the idea that the astrocytes needed a signal to “wake them up” before they could respond to nearby neurons. That is how they found that norepinephrine, the brain’s broadly distributed fight-or-flight signal, primes the astrocytes in both locations to “listen in” on nearby neuronal activity.

    (Continues on next page...)

    From Around the Web...
    XPT Extreme Performance Training combines performance breathing, innovative movement, and recovery...
    DAY THREE We heard from four incredibly wise and informative doctors on Saturday morning. 9 am The...
    Photo by Randall Cordero
    1. You can do it on your lunch break. Even though it works you hard, it does not leave you spent...
    Originally published in the Fall 2015 issue of Robb Report Health & Wellness as “Cognitive...
    Foreo Issa electric toothbrush: $199 Foreo has delivered a new toothbrush aimed at improving on...
    << Back top “80 Amazing Holiday Gifts.” The Level by FluidStance: $289–$429  “I’ve been on my...
    For runners looking to step up their game, Sensoria Fitness Smart Socks has them covered....
    Innovative, inspiring, and intuitive, the Ralph Lauren PoloTech smart shirt is everything you...
    Safe cycling is all about riding smart, and with the Livall Bling Helmet, using one’s head has...
    It is a perilous time to be sick. Medical error kills 400,000 Americans a year, making it the third...