DJ Strouse

Project Title: The Quest for Real-Time Simulations of Neural Synapses
Advisor: Dr. Jean-Marie Bouteiller (Synaptic Modeling Team, Professor Ted Berger’s Center for Neural Engineering, USC)
Timeline: September 2009 to April 2010

For Grandma*:
    Neurons (described above) communicate with one another by squirting chemicals across tiny junctions called synapses. Altering the behavior of synapses can have profound effects on an organism. The venom of pufferfish, bees, and spiders as well as man-made toxins such as mustard gas induce paralysis by interfering with neural communication at synapses. However, not all synaptic modifications are harmful and scientists have devised many common beneficial medications that target synapses, including selective serotonin reuptake inhibitors (SSRIs) such as Prozac and the cheesy smile-inducing cosmetic Botox.
    A group at USC, in collaboration with a French pharmaceutical company, has developed highly detailed computer models of synaptic communication in order to discover new drugs. As of fall 2009, their simulations were running much slower than expected and I discovered the source of this problem and proposed a solution to solve it.

For Einstein:
    During my junior year at USC, I helped the synaptic modeling arm of Professor Ted Berger’s Center for Neural Engineering solve a problem with their simulations. Their numerical integration algorithm was having trouble with the multiple timescales present in biological dynamics, and using methods I knew from computational physics for dealing with stiff equations, I proposed an adaptive algorithm to significantly speed up simulations. Through my encouragement, our collaboration has since led to a series of joint projects between the Berger group and the computational condensed matter group from USC’s physics department, an unprecedented link between USC’s neuroscience and physics communities.
    During this time, I also assisted a graduate student in the neural prosthetics arm of the group in building compartmental models of hippocampal neurons using the simulation package NEURON. Observing the struggles that the neural prosthetics group had in building input-output models of the hippocampus indicated to me the importance of theory in neuroscience, and in particular the importance of linking biological mechanisms with their functional roles in the behavior of an organism.

Example of an early presentation to the group: available for download here

*”You do not really understand something unless you can explain it to your grandmother.” – Albert Einstein