Exploradio Origins: What Causes Spontaneous Activity in the Brain

Sep 5, 2019

It seems our brains are never truly quiet. We dream when we are asleep, and in sensory deprivation experiments, participants start hallucinating within 15 minutes. Where does this spontaneous activity in our brains come from?

"My contention is, based on experiments and computational models, that spontaneous activity is triggered by what is called 'noise,'" said Roberto Galan. 

Galan is an adjunct associate professor in electrical engineering at Case Western Reserve University. He studies how our brains - unlike electronic devices - work with internal noise, and how that noise may lead to the brain’s spontaneous activity.

Roberto Galan is an adjunct associate professor in electrical engineering at Case Western Reserve University.
Credit JEFF ST. CLAIR / WKSU

"The sources of that noise go back to the molecular level," Galan said. "What I think my community has missed is the link between what it is and what it is good for. So with one of my previous students I developed, I improved algorithms and computational models to understand the origin of that noise."

Galan realized that the brain’s hard-wired circuitry –the way our neurons are connected to one another and shaped by our memories and experiences- could organize that molecular noise into coherent signals, which ultimately could be the trigger of our dreams or hallucinations.