The propriety of presenting yet another paper dealing with the physiology of micturition might well be questioned since the literature on the subject has become so voluminous as to be repetitious. The presentation of significant new data or the pointing out of new problems would be adequate justification. In this instance, however, I shall attempt so to strip the subject of its physiologic and neurologic complexities as to provide a useful working concept of bladder activity which the practitioner can utilize in handling his everyday problems. The authoritative work of Denny-Brown and Robertson1 and of Langworthy, Kolb and Lewis2 may be referred to for detailed presentation and analysis of the experimental and clinical evidence.
There are several basic anatomic and physiologic facts that are a prerequisite to an understanding of the problem. Briefly they are as follows: The bladder is made up of smooth or involuntary musculature. The