College of Massage Therapists of British Columbia (CMTBC) Practice Exam

A reflex pathway that includes sensory neurons, interneurons, and motor neurons is called what?

1. Monosynaptic Reflex

2. Polysynaptic Reflex

3. Crossed-Extensor Reflex

4. Golgi Tendon Reflex

The correct answer is: Polysynaptic Reflex

A reflex pathway that incorporates sensory neurons, interneurons, and motor neurons is identified as a polysynaptic reflex. This type of reflex involves multiple synapses, allowing for the integration of information from sensory input and the coordination of a motor response via interneurons. In a polysynaptic reflex, the sensory neuron transmits information about a stimulus to the spinal cord, where it synapses with interneurons. These interneurons then connect to motor neurons, which carry signals to the effectors (muscles or glands) that produce the response. This complexity enables the nervous system to process and modulate reflex actions, providing a sophisticated mechanism for responding to a variety of stimuli. In contrast, a monosynaptic reflex only includes two types of neurons—sensory and motor neurons—connected by a single synapse, making it a simpler pathway. The crossed-extensor reflex is a specific type of polysynaptic reflex that involves coordination between muscles on opposite sides of the body. The Golgi tendon reflex also serves a protective function but involves special receptors that monitor muscle tension rather than the broader inclusion of interneurons for integration of sensory input and motor output.