The nurse is performing a medication history on a patient who reports taking lorazepam (Ativan) for the past 6 months to treat an anxiety disorder. The patient states that the medication is not working as well as previously. The nurse will

A) The patella reflex ("knee jerk") activated by tapping the patella tendon: The patellar reflex is a monosynaptic spinal reflex that involves the somatic nervous system but is a reflex action rather than a voluntary motor function. The somatic nervous system governs voluntary movements, but reflex actions like the patellar reflex are involuntary responses that do not require higher brain input, though they involve somatic motor pathways.

B) Abdominal viscera the beginning of depolarization in the cardiac conduction of impulses: This process is primarily under the control of the autonomic nervous system (ANS), not the somatic nervous system. The ANS regulates involuntary processes like heart rate and digestion, while the somatic nervous system controls voluntary movements and somatic sensation.

C) The act of typing a report using a computer keyboard: Typing is a voluntary motor activity, controlled by the somatic nervous system. The somatic system is responsible for conscious, voluntary actions such as moving muscles in the arms, hands, and fingers to type. This is the most accurate example of a somatic function.

D) Withdrawing the hand after touching a hot surface: This is a reflex action known as the "withdrawal reflex," which involves the somatic nervous system. However, it is an involuntary action triggered by a sensory stimulus. While it does involve the somatic system, it is not a voluntary action like typing, and reflexes are considered part of the automatic response mechanisms.

A) They increase norepinephrine at the neuromuscular junction: Anticholinergic agents do not directly increase norepinephrine at the neuromuscular junction. Instead, they work by blocking acetylcholine receptors (specifically muscarinic receptors) in the parasympathetic nervous system, which reduces parasympathetic activity. Norepinephrine is primarily involved in the sympathetic nervous system, not the action of anticholinergics.

B) They act to block the effects of the parasympathetic nervous system: This is the correct explanation. Anticholinergic agents work by inhibiting the action of acetylcholine at muscarinic receptors, which are part of the parasympathetic nervous system. By blocking these receptors, anticholinergics reduce parasympathetic effects such as slowing of the heart rate, increased glandular secretions, and smooth muscle contraction, leading to effects like increased heart rate, dry mouth, and bronchodilation.

C) They compete with serotonin for muscarinic acetylcholine receptor sites: Anticholinergic drugs do not interact with serotonin receptors. They specifically target muscarinic acetylcholine receptors, which are involved in parasympathetic responses. Serotonin is a different neurotransmitter, and while some drugs may affect both serotonin and acetylcholine pathways, anticholinergic agents do not compete with serotonin at these receptor sites.

D) They block nicotinic receptors: Anticholinergics typically block muscarinic receptors, not nicotinic receptors. Nicotinic receptors are involved in the transmission of signals at the neuromuscular junction and in the autonomic ganglia, while muscarinic receptors are primarily involved in parasympathetic functions. Blocking nicotinic receptors would have different effects and is not the action of anticholinergic agents.