Researchers have revealed that a new study
on mice has shown that the urge to urinate frequently changes brain activity.
Experts at the Children's Hospital of Philadelphia in Pennsylvania say that the results, if they turn out to be true in humans too, may explain the disrupted sleep, reduced ability to concentrate and confusion that often accompany ageing.
"If you have an overactive bladder, you don't just have a bladder problem. It has neurobehavioural consequences," New Scientist magazine quoted neurologist Rita Valentino as saying.
When the animals' brains were scanned, the researchers found increased activation of a region of the brainstem called the locus coeruleus, which helps control alertness.
Valentino points out that this region is activated only when the bladder is full in normal mammals, and helps them to disengage from other activities.
However, in rats with overactive bladders, she and her colleagues found that activation to occur continually.
The researchers said that an overactive locus coeruleus triggered increased and disordered activity in the forebrain that controls higher brain function, something that may lead to anxiety, disrupted sleep and other behavioural problems in humans.
This is the first time that a study has shown that a bladder disorder can have a direct effect on brain function.
"This helps complete the puzzle of why overactive bladder symptoms are so disruptive to quality of life," said Craig Comiter, a urologist at Stanford University School of Medicine in California.
Valentino says that bowel disorders like irritable bowel syndrome may also overactivate the locus coeruleus, and that this may help better understand psychiatric disorders that often accompany IBS.