Rachael Seidler, professor of utilized physiology & kinesiology on the College of Florida will ship this 12 months’s Rose M. Litman Memorial Lecture in Science.
Seidler research the interplay between the mind and motion, and neural adjustments associated to age, illness and spaceflight. Her groundbreaking analysis on astronauts is advancing understanding of the hazards to the human physique posed by house journey.
Area journey has by no means been extra widespread and, in her April 4 speak, “Mind and Behavioral Modifications with Human Spaceflight: Dysfunction and Adaptive Plasticity,” Seidler will talk about her latest findings of the results of microgravity and the way it might have an effect on everybody from house vacationers to astronauts on a prolonged future mission to Mars.
Through the time Seidler has been working with astronauts, together with a decade-long, NASA-funded spaceflight examine, her analysis has make clear what occurs to the human physique when it swaps Earth’s gravity for the microgravity of house. Utilizing superior MRI strategies—scans of astronaut’s brains earlier than and after missions to the Worldwide Area Station—Seidler and her group have investigated shifts in mind perform and construction and what these might imply for stability, mobility and cognition.
Why examine astronauts? For many years, Seidler has been all for neuroplasticity, or the mind’s capability to type new and rearrange previous connections, buildings and capabilities in response to expertise or damage. She wished to reply questions like, the place does the mind retailer motor reminiscences and what does it appear to be once we’re studying new expertise? It was a wealthy path of inquiry but additionally restricted by examine topics who had been both recovering (from a stroke or traumatic mind damage, for instance) or wholesome people who might solely be studied for a restricted time.
In comparison with the common mortal, astronauts are in a league of their very own. They’re usually wonderful bodily specimens however, when on a mission, are topic constantly to antagonistic situations. “I assumed this was only a actually fascinating means of trying on the most capability for neuroplasticity within the wholesome mind,” stated Seidler. “As a result of once you’re in microgravity, you’re uncovered to the stimulus 24 hours a day, the entire time you’re there. You’ll be able to’t even escape it once you’re sleeping.”
For Seidler and colleagues, what started as an inquiry into the results of house on neuroplasticity has revealed rather more. Their latest work, revealed in June 2023 in Scientific Reviews, has proven each adaptive, neuroplastic adjustments in addition to dysfunctional results. Seidler provides the instance of the human ear’s tubular system which helps orientation and stability. Absent gravity, the mind ignores the haywire indicators coming from that system and astronauts be taught to depend on the enter from different senses. “We did definitely see proof for that however we additionally noticed quite a lot of shocking findings that I have a tendency to explain as bodily adjustments,” stated Seidler.
Gravitational shifts
Whereas learning 30 astronauts, each feminine and male, Seidler and colleagues noticed that microgravity publicity has mechanical results on the nervous and circulatory programs. “There are quite a lot of structural adjustments that appear to come back from the physics of the atmosphere relatively than neuroplastic adjustments which may happen with expertise and observe and coaching. And that half was considerably surprising to us,” she stated.
The group noticed that, missing gravity, fluids within the physique shift towards the pinnacle. In her lecture, Seidler will element the mechanisms, impacts and timeline of that response—particularly ventricular enlargement—during which cerebral spinal fluid strikes upwards and forces the mind to take a seat increased within the cranium. Age-related ventricular enlargement as a consequence of pure mind atrophy is related to cognitive decline on Earth, however the implications of that situation for astronauts each in house and after they return residence are nonetheless largely unknown and extra long-term follow-up is required.
“It seems that there are quite a lot of issues about human physiology which have tailored to both leverage gravity or have tailored to counteract the results of gravity,” stated Seidler. “So it’s actually fascinating to see how these programs work and performance when there isn’t a gravity and it’s one thing an individual has by no means skilled earlier than.” With the implications for long-term mind well being nonetheless being studied, Seidler’s lab has just lately been awarded a 10-year grant from NASA to research mind restoration as much as 5 years postflight.
In her speak, Seidler can even contact on massive particular person variations within the adjustments that happen, associated to the house vacationers’ age, intercourse and prior spaceflight expertise. Given NASA’s plan to ship a manned mission to Mars within the 2030s, Seidler stated scientists must work effectively to guard astronauts from house dangers to the human physique. (She can be concerned in a NASA undertaking aimed toward mitigating Mars mission well being hazards.)
“I believe understanding particular person variations has huge sensible implications when it comes to the way you would possibly design the mission,” stated Seidler. “However I additionally suppose it’s actually fascinating scientifically, when it comes to what it could imply about our brains and our adaptability.”
Earthy impacts of interstellar breakthroughs
By observing astronauts, scientists may also be taught rather a lot about supporting human well being on Earth. For instance, understanding bodily responses to microgravity might assist deal with comparable situations that happen daily on our planet (reminiscent of hydrocephalus, a neurological situation brought on by a buildup of cerebrospinal fluid within the mind’s ventricles). Seidler’s work additionally extends to age-related mobility points and, with a $5.6 million Nationwide Institutes of Well being (NIH) grant, her analysis explores how the mind compensates for declines, in an effort to stop falls in older adults.
Seidler has authored roughly 175 papers in journals reminiscent of Science, JAMA Neurology, Lancet Neurology and extra, and her analysis has been cited greater than 17,000 occasions. All through her educational profession, she has secured tens of millions of {dollars} in analysis grants from famend establishments like NASA, NIH, Nationwide Science Basis and the Translational Analysis Institute for Area Well being.
Seidler is fiercely dedicated to mentorship and to inspiring the subsequent era of numerous feminine scientists. Every summer season, her lab runs a week-long “Ladies with Nerve” camp aimed toward cultivating curiosity in STEM sciences and empowering ladies, and underserved minority college students specifically, to discover neuroscience.
