Biological Bases of Behavior: Nervous and Endocrine Systems (7A) Practice Test

A patient presents with a rare autoimmune disorder that specifically targets and destroys Schwann cells. Which of the following physiological changes would most likely be observed in this patient's peripheral nervous system?

Which of the following neurotransmitters is primarily responsible for the inhibitory tone of the central nervous system, and which ion channel does it typically open to achieve this?