Brain warning system failure is related to post-stroke

A groundbreaking imaging study conducted at the USC identified specific brain networks of urethral control that lead to malfunction of stroke survivors, providing new hope for the treatment of common but often overlooked complications.

The study, published this month in the journal Stroke, revealed that a network of brain regions known as the “significance network” failed to properly activate among stroke survivors suffering from urinary incontinence—a disease that affects up to 79% of patients after stroke and continues by nearly 40% a year later.

The researchers observed brain activity during voluntary and involuntary bladder emptying using innovative functional magnetic resonance imaging (fMRI) techniques, making this the first study to identify different neural patterns during a failed episode.

“The brain plays a crucial role in regulating the bladder, allowing people to sense the bladder fullness and allowing them to delay urination until it is properly or at will in society.”

“In contrast, stroke survivors often struggle to suppress unnecessary bladder contractions and may even lose their senses and consciousness completely,” Creading notes.

This situation goes beyond the inconvenience. Medical records show that post-stroke incontinence predicts poor recovery outcomes, including higher mortality and increased disability – but remains untreated in many clinical settings.

What is particularly valuable about this study is its methodological innovation. Instead of the traditional method of getting participants into the MRI scanner, the researchers developed a system to observe repeated fill and emptying cycles while recording brain activity and bladder pressure. Instead, the researchers developed a system to observe repeated fill and emptying cycles.

“In contrast to previous studies, participants using catheters entered the scanner with a complete bladder and invalidated our study, our study allowed us to repeatedly observe fill and invalidate,” said Imaging Expert, Kay Jann, from USC Mark and Mary Steevens Neuroimiganting and Inlictatics Institute. “Simultaneous recording of bladder pressure allowed us to determine voluntary and involuntary bladder emptying. This allowed us to detect the first time differences in brain activity in the period of involuntary emptying.”

These findings reveal a sharp contrast. During voluntary urination, healthy individuals and stroke survivors showed significant activation in brain regions associated with sensorimotor control and decision-making. However, in the involuntary bladder emptying of stroke survivors, the researchers observed minimal brain activation, indicating a rupture of the neural network that controls urination.

Most notably, the study identified a significance network—a collection of brain regions that evaluate the importance of internal body signals—a key component in preventing urinary incontinence. Although the network was properly activated during the bladder filling process during voluntary urination in healthy individuals and stroke survivors, it was still inactive when stroke survivors experienced involuntary urination.

This neural signaling could be the target of new treatments, including non-invasive brain stimulation techniques, drugs that enhance nerve activation or cognitive training designed to improve voluntary control.

These findings won the prestigious McGuire-Zimskind Award for Urdynamics, the Women’s Pelvic Medicine Association and the genital reconstruction, winning the prestigious McGuire-Zimskind Award.

Dr. Charles Liu, director of the USC Center for Neurological Horticulture and senior author of the study, believes that the study opens the door to the development of targeted therapies. “The neurological basis of urination remains seldom understood, and further research is crucial for the neurologic cultivation of the urine and reproductive system,” Liu said. “This work not only deepens our understanding of common posterior posterior complications, but also provides hope for the quality of life of millions of stroke survivors around the world.”

The multidisciplinary research team includes urologists, neurosurgeons and imaging specialists at USC Keck Medical School, USC’s Keck Medicine, Rancho Los Amigos National Rehabilitation Center and Shirley Ryan Competency Laboratory.

While currently focusing on understanding the mechanisms of post-power incontinence, the researchers hope that future research will explore how different types of strokes affect urinary control and whether early interventions targeting the significance network may prevent chronic urinary incontinence – ultimately recovering the millions of quality of life affected by this challenging condition.