The connection between two key parts of the brain plays a role in neuropsychiatric brain disorders

Florida State University researchers have identified a link between two key parts of the brain that play an important role in conditions such as Alzheimer’s disease, post-traumatic stress disorder, schizophrenia and depression.

Associate Professor of Psychology and Neuroscience Wen Li and PhD Candidate in Psychology Kevin Clancy found that stimulating the brain system that deals with attention and imagery also improves the efficiency of what is called network in default mode, a key element of the functional organization of the brain. The default mode network is disrupted in a host of neurological disorders.

Their study was published in the Proceedings of the National Academy of Sciences of the United States of America.

This research has important implications for so many different scientific disciplines. From a cognitive neuroscience perspective, the brain activity we targeted is involved in a range of fundamental human mental faculties, such as consciousness, self-awareness, attention and memory. Our ability to directly manipulate this brain activity could lead to a better understanding of how these mental processes take place. From a clinical perspective, disruption of this neural activity has been implicated in the development and maintenance of various serious neuropsychiatric disorders.”

Kevin Clancy, PhD student in psychology

Brain function is organized by intrinsic inter-regional connectivity, that is, the way different regions of the brain interact, and inter-neuronal synchrony, which is the simultaneous activation of neurons in multiple areas of the brain. brain. These processes are represented by the brain’s default mode network and alpha – oscillations; or neural activity associated with attention and imagery -; and these systems are mechanically linked.

“Our results showed that transcranial stimulation of alpha oscillations can help regulate and improve network efficiency in default mode,” Li said. “The fact that this stimulation upregulates the network in default mode highlights an effective, non-invasive therapy to normalize network functioning in neuropsychiatric disorders.”

This work was made possible through the use of Florida State University’s Functional Magnetic Resonance Imaging Facility. The state-of-the-art neuroimaging facility fosters cutting-edge research and collaboration between the fields of neuroscience, psychology, medicine, and engineering.

Li and Clancy used the main components of the fMRI setup, including a Siemens Prisma scanner and a high-density EEG/ERP system, which stands for electroencephalography and event-related potential. EEG is a method that records the electrical activity of a brain through sensors on an individual’s scalp that detect brain activity underneath, and ERP is the measured brain response resulting from a stimulus. These methods help capture neural activity related to sensory and cognitive processes, and Li and Clancy have further integrated transcranial stimulation with MRI-EEG recordings.

Delivering transcranial stimulation while simultaneously measuring brain activity and response to stimulation is a tricky process, as participants must be kept comfortable in the scanner while attached to various electrodes and sensors.

“Achieving this kind of technical sophistication and rigor in simultaneous recordings is a great achievement. Although these are effective techniques on their own, the study would lose power if these methods were not conducted at the same time” , said Li, who played a major role in designing and implementing this powerful protocol at the MRI facility. “Kevin was resourceful in how he set up the electrodes for stimulation and the cap for recordings to keep participants comfortable.”

The technology used in this research acts directly on the brain, and this neuromodulation technique is cost-effective on an outpatient or outpatient basis and does not require extensive training to administer. Clancy hopes this work can help bridge community mental health and interventional psychiatry to facilitate accessibility to high-quality, evidence-based mental health treatment.

“I am currently writing grant applications for new research in this area – we want to apply these findings to post-traumatic stress disorder and chronic pain,” Li said. “Eventually, we hope to study the effect of this link about Alzheimer’s disease and other neuropsychiatric disorders.


Journal reference:

Clancy, K.J. et al. (2022) Transcranial stimulation of alpha oscillations upregulates the default mode network. PNAS.

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