According to Cartesian dualism, we don't think with our brains; we think with our minds. So for the Cartesian dualist, the brain must be nothing more than a sophisticated relay station, receiving messages from the mind and sending messages to it. On this view, those suffering from severe brain damage or from diseases such as Alzheimer's have not suffered any cognitive impairment at all. Their minds are just as good as they ever were, they have simply lost the ability to communicate with their bodies. Is this plausible? Are minds unaffected by brain damage or disease? Or does the loss of brain function also result in a loss of mental function? Which explanation is the most plausible? Why?