Although we are concerned with the medical aspect of the problem of consciousness, in this article, to be thorough with our subject, we have started with the literal meaning and the etymology of consciousness in the western [language]s, followed up with a brief historical summary of its philosophical aspects, and lastly tried to explain the subject in terms of neurophysiological and neuropsychiatric considerations.
The neurophysiological considerations of the problem of consciousnes have been especially emphasized, and in this connection the subjects of the Brain - stem reticular formation, the Ascending Reticular Activating System, Reticular formation and sleep, Cortex and Attention, Attention and reticular formation, the physiology of sleep have been discussed.
As a conclusion, it has been pointed out that our present knowledge about consciousness as a process is still insufficient and more knowledge about this process will only be obtained with the further development of neurophysiology and eletrophysiology.