Gut microbiome–brain connection with Sarkis Mazmanian

Credit: Lance Hayashida/Caltech

Trust Your Gut: Microbiome Influences on Brain Health and Disease

Learn about the science behind the gut–brain connection and its impacts on behavior and brain function.

Advance registration for Mazmanian's talk is full. Guests who have not registered are still welcome to attend the preshow, which does not require registration, beginning at 6 p.m., featuring food, music, and interactive displays.

After the preshow, non-ticketed guests interested in attending the talk may join our standby line by 6:50 p.m.

Date: Wednesday, December 2, 2026
Time: 7:30 p.m. PT.
Where: Beckman Auditorium
Admission: Free, but registration is required

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About Mazmanian's Talk

While the brain receives visual, auditory, olfactory, and other sensory information, the majority of molecular input to the brain comes through our gastrointestinal tract. Rather than being isolated, the brain is in constant communication with the gut via neuronal connections, the immune system, or intestinal hormones. Remarkably, many molecules produced by gut bacteria of the human microbiome can be found in the brain.

In this talk, Sarkis Mazmanian, the Luis B. & Nelly Soux Professor of Microbiology and a Merkin Institute Professor, will share his laboratory's work on the fascinating and enigmatic gut–brain connection and its impacts on behavior and brain function. Harnessing the link between gut bacteria to the brain may uncover causes for disorders such as Parkinson's disease, and it may also enable therapies based on entirely novel biological principles.

About the Speaker

Sarkis Mazmanian, Professor of Microbiology at Caltech, focuses his lab's work on the gut microbiome and its implications for immune and neurologic health. His research has uncovered insights into how the gut—brain connection is influenced by the microbiome to mediate behavioral abnormalities, motor deficits, neuro-inflammation, and brain pathologies.

In further research, Mazmanian found that the microbiome can impact brain function and neurodegeneration. This work drew him to study Parkinson's disease, where the majority of individuals have gastrointestinal symptoms, revealing that the gut microbiome can trigger movement disorders via specific microbial molecules that serve as targets for novel treatments. Findings from his laboratory have formed the basis of ongoing clinical trials in humans.

Before Caltech, Mazmanian was a fellow and an assistant professor of medicine at Brigham & Women's Hospital / Harvard Medical School. He graduated from the University of California, Los Angeles where he also received his undergraduate and doctoral degrees in microbiology and immunology.