Reply to comment

After reading numerous postings on motion sickness I began to wonder how we prevent it. Dramamine (dimenhydrinate) an oral medication and Transderm Scop (scopolamine) a patch you place behind your ear are perhaps the two most widely prescribed treatments. Having previous experience with both drugs I never realized they actually worked by crossing the blood brain barrier and acted in the central nervous system. After last weeks lecture it seems incredibly obvious now that the most logical place to send inhibitors would be the brain. Scopolamine (in Transderm Scop) works by inhibiting the secretion of saliva and sweat and decreasing gastrointestinal secretions and motility. More directly- the medicine works by reducing the activity of nerve fibers in our inner ear- which is as we discussed in class what brings about the discrepancy between the sensory discharge and the corollary discharge. Unfortunately from reading through the pharmacology of this medication I couldn’t distinguish between whether or not the drug is acting on one particular system-such as the sensory discharge- because it is directly reducing the movement in our ear, or if it is working on both sensory and corollary because it is effecting the entire system? Regardless, it is amazing that chemical inhibitors are able to have what seems to be pretty direct control over various inputs and expectations. With that in mind, perhaps I am missing something in the complete understanding of how the drug is working, but if we are able to develop a drug that is inhibiting one type of mismatch between sensory discharge and corollary discharge, then why can’t something similar be developed to control the sensations of phantom limb?Drug Info: http://www.rxlist.com/cgi/generic/transscop_cp.htm