Blood Oxygenation-Level Dependent Signals A Marker Of Brain Activity, Study Shows

Researchers at Vanderbilt University have uncovered a remarkable finding within the human brain, detecting an inexplicable and powerful signal in the cerebral white matter.

White matter links cells and transmits signals 

The human brain consists of the gray matter and white matter. Gray matter, where nerve cell bodies reside, plays a crucial role in handling sensory input, regulating voluntary motion, and facilitating functions such as speech, learning, and cognitive processes. Conversely, white matter functions as an extensive system of interconnections that establish links between cells and transmit signals throughout the body.

Researchers at Vanderbilt University aim to shift the prevailing scientific focus from the gray matter of the brain, often considered the central hub of activity, to the underappreciated white matter, which accounts for half of the brain’s composition. This initiative seeks to alter the current narrative in neuroscience.

For years, a group headed by Dr. John Gore, who serves as the director of the Vanderbilt University Institute of Imaging Science, has been utilizing functional magnetic resonance imaging (fMRI) to identify blood oxygenation-level dependent (BOLD) signals, a vital marker of brain activity, within the white matter of the brain.

White matter plays a role in epilepsy and Alzheimer’s 

In their most recent investigation, scientists have unveiled an astounding discovery: during fMRI brain scans of individuals engaged in activities like moving their fingers, there is an observable enhancement in BOLD signals throughout the white matter of the entire brain.

The discovery is important as it highlights the role of white matter in brain disorders like epilepsy and multiple sclerosis, which affect brain connectivity. This finding calls for further research. Scientists intend to investigate changes in white matter signals in conditions such as schizophrenia and Alzheimer’s using animal studies and tissue analysis to understand the biological basis of these changes.

BOLD signals in gray matter indicate increased blood flow and oxygen consumption in response to nerve cell activity. It’s unclear whether axons or glial cells consume more oxygen during brain activity or if the signals are related to gray matter processes. Additionally, there are unique changes in white matter pathways, even without biological activity.