Brain Bits, 2/27/16

lightning brain2

credit: A. Ajifo

Welcome to Brain Bits, where I highlight important or interesting recent news in the world of neuroscience. I know guys, I’ve been falling behind in writing full-length posts because I’ve been incredibly busy this semester, but I thought some Brain Bits would at least tide you over for now. In store for today: revolutionizing scientific publishing, how your different senses interact, a new method for studying human brain function, and more!

 

rainbow unicorn

the mascot of the ASAPbio movement

As you’ll know if you’re a scientist who’s been anywhere near Twitter lately, a movement to transform scientific publishing has been gaining momentum. Some prominent scientists have proposed that biology research should be published in online depositories such as bioRxiv rather than in traditional journals, which would make findings immediately accessible to the scientific community as well as the general public. This online publishing model would rely on post-publication review by anyone willing to comment online instead of pre-publication review by two or three experts chosen by journal editors. Last week leaders in this movement met at the ASAPbio meeting to discuss steps to implement this system. For more, read this summary article and pretty much anything on Michael Eisen’s blog, starting here.

 

Santa Cruz Biotechnology, a major biotech vendor known best for producing research-related antibodies, has come under fire for potential animal mistreatment. The company had previously been cited by the USDA for multiple violations, such as poor housing conditions and sick animals. Now Nature News reports that in the latest USDA inspection, Santa Cruz Biotech’s entire animal inventory seems to have disappeared. Since the company refuses to comment on this mysterious disappearance of thousands of animals, many people assume that they were killed to hide evidence of more violations. Either way, smells like a cover-up. I encourage fellow scientists to stop buying products from this company immediately.

 

fig1

Figure from Tuthill and Wilson (2016) showing touch neurons in the fly leg.

How does the nervous system interpret the sense of touch? We have zillions of touch receptors all over our body, and our brains must piece together all this information to figure out what we’re touching. A new paper in Cell has now discovered some of the neural circuits that process tactile information in the fruit fly. This tour-de-force study used some really sophisticated methods to identify, for the first time, neurons in the central nervous system that directly receive tactile information from touch receptors on the fly’s legs. The study identified three types of neurons, each serving a different purpose: one type compares touch signals on different parts of the same leg, a second type compares signals from the left and right legs, and a third compares information about touch and proprioception (the sense of how your limb is positioned in space). These parallel neural pathways may explain how animals can so adeptly use the sense of touch to identify and respond to objects in their environment.

 

Most of the cool neuroscience studies I tell you about are performed in animal models, because in general it’s pretty freaking hard to conduct meaningful experiments in humans that really probe the mechanisms of the brain. But a new study published in Neuron uses a new method, focal cooling of brain tissue in human surgical patients, to examine the brain areas involved in speech. Decreasing the temperature disrupts neural circuit function, so cooling specific brain regions can help us figure out what they’re doing—especially in humans, where you don’t want to perform more drastic experiments such as cutting out chunks of the brain or injecting drugs that block neuronal activity. You do need to expose the surface of the brain, however, so brain cooling in humans can only be ethically performed on patients who are undergoing brain surgery for a medical reason. This particular study used focal cooling to determine that different brain areas control the articulation and timing of speech: cooling one area affected the quality of speech but not its timing, whereas cooling the other area caused speech to slow down or speed up, but did not affect its quality. This study not only provides insight into how the brain controls speech, but also validates brain cooling as a useful method for future studies of human brain function.

long 2016

Data from Long et al. (2016) showing that different brain areas (both in the the left hemisphere only) control the timing and quality of speech.

 

Most neuroscientists study the brain regions involved in just one sense at a time, such as vision, touch, or hearing, even though in real life we typically use many of our senses simultaneously. A new study in Neuron now sheds light on how two of our senses, vision and hearing, interact with one another. The study found a direct connection between two of the earliest brain regions involved in processing vision and hearing, the primary visual and auditory cortices, showing that brain pathways for different senses interact early on rather than only merging higher up in the brain, as some have argued in the past. Due to this connection, the presence of sound sharpened the responses of visual neurons, making the them fire more strongly to the specific patterns that normally excited them. This interaction might help animals detect predators or prey in their environment: as you hear something moving, your visual acuity improves to help you identify it.

 

Did you see any recent neuroscience news that you’d like to share? Leave a comment below!


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