Review Question - QID 210942

A scientist is studying patients with neuromuscular weakness and discovers a mutation in a plasma membrane ion channel. She thinks that this mutation may have an effect on the dynamics of action potentials so she investigates its effect in an isolated neuronal membrane. She finds that the ion channel has no effect when potassium, sodium, and calcium are placed at physiological concentrations on both sides of the membrane; however, when some additional potassium is placed inside the membrane, the channel rapidly allows for sodium to enter the membrane. She continues to examine the mutant channel and finds that it is more rapidly inactivated compared with the wildtype channel. Which of the following effects would this mutant channel most likely have on the electrical profile of neurons in these patients?