Dr. Shulman Replies

To the Editor: Dr. Gossart’s reaffirmation of the mind-brain linkage was, as he indicated, in agreement with my review. Psychiatrists, among others, by interpreting functional imaging experiments in terms of incremental localized activity, assume a particular model of mind-brain dualism, which breaks the linkage. The mind, in this interpretation, consists of computer-like modules that respond to specific stimuli. My article showed high rates of neuronal firing in the resting brain, which are required for purposeful brain behavior. The presence of these large, meaningful neuronal activities at rest allows for explanations in terms of subjective dynamics. If psychiatry were to use its core understanding to interpret these measurements of resting brain activity, it would be well positioned to explore mechanisms linking brain and mind. However, if we continue to use a psychology that ignores unconscious activities in order to explain functional imaging, the mind, the behavior of the brain, will remain a distant, dualistic goal.