San José

A Neurophysiology Lab at SJSU Explores How and Why the Human Body Interacts With the World Around Us

Physiology

 

​​​The human body has between 800 and 900 muscles. Each one has anywhere from five to 50 stretch sensitive sensory neurons—cells that help the brain build a three-dimensional representation of the body in space. This sense of position in space, known as proprioception, helps people move. If sensory neurons fail, it affects how a person moves.

“How does your body take sensory information and use that to do the things that you need to do?” asked Katie Wilkinson, associate professor of biological sciences at San José State. She trains students to use electrophysiological tools to record activity in muscles, examine sensory neurons and study possible applications of these findings to health care and robotics. 

Her team explores how people use sensory information to move, balance and position ourselves— how and why the human body interacts with the world. They study how proprioceptors sense muscle length, when and why they fail and explore how stretch sensors in muscles work. The data they collect could help scientists understand how neurons communicate movement, which could aid people who have trouble with balance.

Dr. Wilkinson hopes their research will help identify therapies for patients whose sensory neurons do not work well. Their findings could apply to prosthetic limbs or robotics. 

“We have sophisticated robotics and prosthetic limbs, but their senses, even with top-of-theline sensors, are nowhere near as good as ours,” she said. “We have circuits built in—some are very quick reflexes and some go to the brain and smooth our movement and adapt to challenging environments. Understanding the basic science of how our sensory neurons work may help us translate that into prosthetics, give people more sensation and perhaps a better range of movement.  My lab pursues very basic science research but, hopefully, some of the things we learn can contribute to that.” 

Dr. Wilkinson came to SJSU after completing an Institutional Research and Academic Career Development postdoctoral fellowship at Emory University that emphasized mentorship, teaching and research experience. She said that she sought out SJSU because it values teaching as much as research. She believes in creating opportunities for students to pursue big questions and contribute to discoveries and experiments.

Her lab studies the mutations that occur in people living with distal arthrogryposis type 5, a rare disorder that causes limb dysfunction, joint rigidity or limb deformities. The goal is to identify how sensory neurons work and pinpoint potential therapies. Together with her master’s and undergraduate students, they are applying for research grants, gathering and analyzing data, publishing papers and presenting at conferences. Wilkinson is guiding generations of scientists as they find their way to careers in academia, biotech and research.

To understand what causes neurological problems, scientists must first identify where and when they occur. How can a doctor treat a disease if it’s unclear how it originates? By investigating how proprioceptors sense muscle length and how stretch sensors work, Wilkinson and her team, in collaboration with Ardem Patapoutian’s lab at The Scripps Research Institute, identified the ion channel that opens when muscles stretch. This discovery, the subject of a cover article in Nature Neuroscience in 2015, locates where mutations that cause imbalance or neurological problems may sometimes occur.

“We are doing cutting-edge science here at San José State,” she said. “Students are publishing papers and contributing to their disciplines. Universities should be where you make new knowledge—and that’s how we train students. Teach them what science really is. Students leaving our lab are well-trained and competing on equal footing with students from other universities. San José State students are some of the most motivated people I’ve ever met.”