The planning of this Study Week at the Pontifical Academy of Science from September 28 to October 4, 1964, began just two years before when the President, Professor Lemaitre, asked me if 1 would be responsible for a Study Week relating Psychology to what we may call the Neurosciences. 1 accepted this responsibility on the understanding that 1 could have as sistance from two colleagues in the Academy, Professors Heymans and Chagas. Besides participating in the Study Week they gave me much needed assistance and advice in the arduous and, at times, perplexing task that 1 had undertaken, and 1 gratefully acknowledge my indebtedness to them. Though there have been in recent years many symposia concerned with the so-called higher functions of the brain, for example with percep tion, learning and conditioning, and with the processing of information in the brain, there has to my knowledge been no symposium specifically with brain functions and consciousness since the memorable treating Laurentian Conference of 1953, which was later published in 1954 as the book, "Brain Mechanisms and Consciousness.