What type of reflex is micturition?

The micturition reflex is a bladder-to-bladder contraction reflex for which the reflex center is located in the rostral pontine tegmentum (pontine micturition center: PMC). There are two afferent pathways from the bladder to the brain. One is the dorsal system and the other is the spinothalamic tract.

What do you mean by micturition reflex?

micturition reflex. contraction of the walls of the bladder and relaxation of the trigone and urethral sphincter in response to a rise in pressure within the bladder; the reflex can be voluntarily inhibited and the inhibition readily abolished to control micturition.

What part of the nervous system mediates the micturition reflex?

The micturition reflex is peripherally mediated by components of the somatic and the autonomic nervous systems. The bladder receives its motor innervation through the parasympathetic pelvic nerves.

Where is the micturition reflex initiated spinal cord?

Micturition is initiated by a supraspinal reflex pathway that passes through a centre in the brainstem. The pathway is triggered by myelinated afferents (Aδ-fibres), which are connected to the tension receptors in the bladder wall.

What nerve controls micturition?

Autonomic Nervous System: Central Urogenital Control☆ Micturition is mediated by activation of the sacral parasympathetic efferent pathway to the bladder and the urethra, as well as by reciprocal inhibition of the somatic pathway to the urethral sphincter (Table 1; Fig.

Is micturition carried out by a reflex?

As the bladder fills, many micturition contractions begin to appear. These are the result of a stretch reflex initiated by sensory stretch receptors in the bladder wall. This is called a micturition reflex.

Is the micturition reflex voluntary or involuntary?

The act of micturition is an autonomic reflex at the level of the spinal cord. This reflex also helps to complete micturition when the act is voluntarily initiated, or when it follows a period of inhibition by the brain, by relaxing the external sphincter.

Which of the following is responsible for micturition?

Micturition is mediated by activation of the sacral parasympathetic efferent pathway to the bladder and the urethra, as well as by reciprocal inhibition of the somatic pathway to the urethral sphincter (Table 1; Fig. 6B).

Which of the following statement is correct wrt micturition reflex?

is correct. CNS passes on motor messages to initiate relaxation of urethral sphincters is the correct answer. Note: The process of voiding the bladder to pass urine out of the body is called micturition which is a voluntary process and is controlled by the micturition reflex.

Is micturition sympathetic or parasympathetic?

The micturition or emptying phase displays a coordinated relaxation of the inner and outer urethral sphincters, under sympathetic and somatic regulation respectively, with strong contractions of the detrusor muscle due to parasympathetic impulses.

What divisions of the nervous system is involved with micturition?

Central control of micturition is performed by 3 areas: the sacral micturition center, the pontine micturition center, and the cerebral cortex. The sacral micturition center is located at the S2-S4 levels and is responsible for bladder contraction.

Is increased micturition an effect of the sympathetic nervous system or the parasympathetic nervous system?

The sympathetic activity also inhibits parasympathetic stimulation, preventing bladder contractions. When the sympathetic nervous system is active, urinary accommodation occurs and the micturition reflex is suppressed.

Is the micturition reflex completely autonomic?

The micturition reflex is a completely autonomic spinal cord reflex, but it can be inhibited or facilitated by centers in the brain.

What happens to the micturition reflex if the spinal cord is damaged?

If the spinal cord is damaged above the sacral region but the sacral cord segments are still intact, typical micturition reflexes can still occur. However, they are no longer controlled by the brain.

How does cortical control override the micturition reflex?

Afferent firing frequency increases with filling, but cortical control still overrides the micturition reflex until voluntary voiding is determined upon. During micturition, urinary flow is assisted by additional detrusor contractions and external sphincter relaxation which further lowers resistance to the passage of urine.

What happens to the micturition reflex when the bladder is partially filled?

When the bladder is only partially filled, these micturition contractions usually relax spontaneously after a fraction of a minute, the detrusor muscles stop contracting, and pressure falls back to the baseline. As the bladder continues to fill, the micturition reflexe s become more frequent and cause greater contractions of the detrusor muscle.