Past, Present, and Future in the Study of Neural Control of the Lower Urinary Tract

Abstract

The neurological coordination of the lower urinary tract can be analyzed from the perspective of motor neurons or sensory neurons. First, sensory nerves with receptors in the bladder and urethra transmits stimuli to the cerebral cortex through the periaqueductal gray (PAG) of the midbrain. Upon the recognition of stimuli, the cerebrum carries out decision-making in response. Motor neurons are divided into upper motor neurons (UMNs) and lower motor neurons (LMNs) and UMNs coordinate storage and urination in the brainstem for synergic voiding. In contrast, LMNs, which originate in the spinal cord, cause muscles to contract. These neurons are present in the sacrum, and in particular, a specific neuron group called Onuf’s nucleus is responsible for the contraction of the external urethral sphincter and maintains continence in states of rising vesical pressure through voluntary contraction of the sphincter. Parasympathetic neurons originating from S2–S4 are responsible for the contraction of bladder muscles, while sympathetic neurons are responsible for contraction of the urethral smooth muscle, including the bladder neck, during the guarding reflex. UMNs are controlled in the pons where various motor stimuli to the LMNs are directed along with control to various other pelvic organs, and in the PAG, where complex signals from the brain are received and integrated. Future understanding of the complex mechanisms of micturition requires integrative knowledge from various fields encompassing these distinct disciplines.

Bacterial Colonization as a Possible Source of Overactive Bladder Symptoms in Pediatric Patients: A Literature Review

“…The pathophysiology of OAB is not completely understood and is believed to be multifactorial [ 24 , 25 , 29 , 33 ]. One theory is that the urgency and related symptoms stem from a cortical immaturity of the centers responsible for controlling urination [ 15 , 34 ].…”

“…Then, cortical inhibitory pathways and the pontine micturition center along with periaqueductal grey matter, anterior cingulate gyrus, and the autonomic, somatic, and sensorial autonomic nervous systems are developed, and urination becomes voluntary [ 36 ]. The prefrontal cortex starts to maintain top-down control over more primitive afferent pathways of the brain, such as the limbic and paralimbic systems [ 24 ].…”

“…It is possible that the urinary frequency typically associated with urgency urinary incontinence alters the microbial community. Significant new findings have highlighted the non-barrier role of the urothelium, especially its sensory functions [ 24 , 33 , 72 , 73 ]. As there is clear evidence of communication between the bladder and the brain, it is biologically plausible that the urinary microbiota may play some role in this communication.…”

“…The pathophysiology of OAB is not completely understood and is believed to be multifactorial [ 15 , 23 , 24 , 25 , 26 ]. One proposed hypothesis is that dysbiosis of an individual urinary microbiome could induce or potentiate OAB symptoms [ 16 , 27 , 28 , 29 , 30 ].…”

Personalized Urination Activity Management Based on an Intelligent System Using a Wearable Device

“…Various methods and learning algorithms for motion recognition have been proposed. Most studies have used static algorithms such as artificial neural networks [7][8][9][10][11] and K-means clustering [12][13][14], or dynamic time warping [15] in combination with algorithms. However, a time series algorithm should be used to predict or classify dynamically changing time series data.…”