Bulbocavernous Reflex

BULBOCAVERNOUS REFLEX, Onanov's reflex, is elicited by irritation of the glans penis (gentle compression of the glans with fingers followed by release) and manifests as contraction of the musculus bulbocavernosus. The reflex arc of this reflex corresponds to the third sacral segment. BULBUS (Latin.), bulb, bulb-like swelling, expansion of a hollow or solid organ: for example, bulbus aortae - the initial expanded portion of the ascending aorta, provided with three bulges; sinus aortae (Valsalvae), located behind the origin of the pulmonary artery; B. cornus posterioris ventriculi lateralis - a white swelling formed by the occipital part of the radiatio corporis callosi; B. medullae - medulla oblongata; B. oculi - see Eye; B. olfactorius - olfactory bulb, the anterior thickened end of the tractus olfactorii (see Rhinencephalon, olfactory brain); B. ovarii - bulb of ovary, venous plexus in its hilum; B. pili - hair follicle, thickening of the hair root, into which the hair papilla extends; B. urethrae - bulb of urethra, the expanded posterior end of its cavernous body; B. venae jugularis inferior, superior - swelling of the jugular vein immediately above the subclavian vein and in the jugular fossa under the base of the skull; bulbus vestibuli - an elongated-round swelling body, located under the urogenital triangle (triangulum urogenitale), at the entrance to the vagina, it is the homolog of the male bulb of the urethra.