In adults, the PMC can be consciously suppressed until voiding is desired. Such suppression depends on inputs from cortical areas that include the prefrontal cortex, anterior cingulate cortex, and periaqueductal gray. In infants, primitive sacral reflexes promote voiding without the involvement of higher brain areas, such as the PMC. These reflexes eventually become subjected to the control of the PMC and modulatory inputs from the prefrontal cortex.

VOIDING DYSFUNCTION

Voiding dysfunctions reflect abnormalities in either the normal anatomy or neural control of the lower urinarytract. The major causes of chronic voiding dysfunction can be broadly classified as:

1. Neuropathic dysfunction
   
2. Stress urinary incontinence
   
3. Urge urinary incontinence

Of note, overflow incontinence often occurs secondary to neuropathic dysfunction or chronic outlet obstruction, and it is thus not considered a primary form of incontinence.