Which of the following statements regarding pain pathways is FALSE?
A) Substance P is an important neurotransmitter in specific pain pathways.
B) Transmission of information in pain pathways may be inhibited by activation of neurons that synthesize opiate neurotransmitters.
C) Synaptic activity in afferent neurons associated with pain receptors can be inhibited by axon-axon synapses with neurons from descending pathways.
D) Afferents neurons that detect painful stimuli in the skin can converge onto common ascending pathways with neurons that detect painful stimuli in internal organs.
E) Substance P is released by neurons descending from the brain, and it inhibits activation of ascending pain pathways.

Question

Quizplus · Accepted Answer

Substance P is actually an important neurotransmitter in specific pain pathways, particularly those involved in transmitting and enhancing pain signals. It is not released by descending neurons to inhibit activation of ascending pain pathways, as stated in option E. Instead, activation of descending pathways can help to inhibit activity in ascending pain pathways through various mechanisms such as opioid-mediated inhibition and axon-axon synapses, as mentioned in options B and C. Option D is also true, as convergence of afferent neurons with different origins onto common ascending pathways is a common feature of pain processing.

Which of the Following Statements Regarding Pain Pathways Is FALSE