Stefan Everling

Robarts Scientist, CFMM
Professor, Departments of Physiology, Pharmacology & Psychology, Western University

Stefan Everling

 

 

Stefan Everling focuses on the cognitive control of eye movements and visual attention, using both high-density single neuron recordings in awake behaving nonhuman primates as well as fMRI in humans and nonhuman primates. His recent studies on the homology and dynamics of resting state networks in humans and NHPs opens up the possibility of doing resting state studies in NHPs across a whole variety of interventions that are not possible in humans. He leads the development of the nonhuman primate facility at the Centre for Brain and Mind at Western, serving as the Director of this facility since 2003.

Research Summary

 

The Everling Lab investigates the neural mechanisms that enable primates to control their actions, focus attention, and flexibly adapt behavior—core processes of executive function. A central focus is on the prefrontal cortex and anterior cingulate cortex, particularly area 32, regions critical for orchestrating complex cognition and communication. Dysfunction in these networks is implicated in psychiatric and neurological disorders such as schizophrenia, autism, and ADHD.

Our research combines sophisticated behavioral paradigms with state-of-the-art neurophysiological and neuroimaging methods. These include high-density Neuropixels recordings in freely moving marmosets, chemogenetics, cortical microstimulation, and ultra-high field (9.4 T) fMRI. We are especially interested in how prefrontal circuits interact with auditory, premotor, and limbic systems during social communication and vocal behavior.

By integrating comparative and translational approaches, our program seeks to uncover the fundamental brain mechanisms of cognitive control and communication, and how their disruption contributes to mental illness.

Research Questions

One of the central questions in neuroscience is how the brain enables social communication.

How does the prefrontal cortex coordinate with auditory and motor regions to allow primates to produce and respond to vocalizations in contextually appropriate ways? Understanding these mechanisms is essential for uncovering the neural basis of speech and language evolution, and for identifying how disruptions in these circuits contribute to communication deficits in psychiatric and neurological disorders such as autism and schizophrenia.

Another fundamental question is how prefrontal networks flexibly interact with other brain systems to guide behaviour.

How does activity in the anterior cingulate cortex (area 32) regulate attention, decision-making, and the selection of voluntary actions, and how are these processes altered by changes in neurochemistry? Answering this question is critical for developing new diagnostic tools and treatments for disorders that impair executive control, including ADHD, depression, and frontal lobe injury.

One of the fundamental questions in neuroscience is how flexible control of behaviour is implemented in the brain. How are we able to respond automatically to a stimulus in one situation and suppress this automatic response in favour of a voluntary, goal-directed behaviour in a different situation?

Brain disorders are one of the major causes of misery challenging society today. Diseases or damage to the frontal part of the brain, including psychiatric disorders, stroke, and head trauma, often result in profound cognitive disabilities. These disabilities leave functions such as sensation and muscle strength unaffected, but cause patients to have problems with mental functions such as concentration and memory. These symptoms place an enormous physical, mental and social burden on patients, their families, employers and the public health care system. In order to develop improved diagnostic and therapeutic techniques, we need to understand the neural processes in the prefrontal cortex and we have to know how changes in the neurochemistry in this area influence cognitive or executive control.