Question

multiple choice 2 points
which of the following actions are not regulated by dual innervation of the autonomic nervous system?
sensory pain impulses to the brain
heart rate
all of the actions listed are regulated by dual innervation
bronchoconstriction
none of the actions listed are regulated by dual innervation
esophageal peristalsis

Explanation:

Define dual innervation

The concept of dual innervation refers to visceral organs receiving functional nerve fibers from both divisions of the Autonomic Nervous System: the sympathetic division and the parasympathetic division. These divisions typically exert antagonistic (opposing) effects to maintain homeostasis.

Analyze autonomic motor functions

Let us evaluate the motor actions listed in the options:

• Heart rate: Regulated by both sympathetic (increases rate) and parasympathetic (decreases rate) fibers.
• Bronchoconstriction: Regulated by parasympathetic fibers (constriction) and sympathetic fibers (bronchodilation via epinephrine/norepinephrine).
• Esophageal peristalsis: Regulated by both parasympathetic (stimulates motility) and sympathetic (inhibits motility) divisions.

These three actions are classic examples of motor functions regulated by dual autonomic innervation.

Analyze sensory pathways

• Sensory pain impulses to the brain: This represents an afferent (sensory) pathway carrying information from the periphery to the central nervous system. The autonomic nervous system is strictly a visceral motor (efferent) system. While sensory fibers (visceral afferents) often travel alongside autonomic motor nerves, they are anatomically and functionally classified as sensory pathways, not motor regulatory pathways of the autonomic nervous system. Therefore, sensory pain transmission is not regulated by dual autonomic motor innervation.

Answer:

• sensory pain impulses to the brain (Correct answer)
• heart rate
• all of the actions listed are regulated by dual innervation
• bronchoconstriction
• none of the actions listed are regulated by dual innervation
• esophageal peristalsis