There has lately been undertaken at the Nutrition Laboratory of the Carnegie Institution at Washington a very broad and comprehensive study of the effect of moderate doses of alcohol on the healthy and normal human body. The immense scope of the investigation planned may be judged by the fact that under the physiological division of the research, as laid out by Professors Raymond Dodge and E. C. Benedict, there are seven main sections and one hundred and sixty subdivisions. The program has been arranged after conferences, either in person or by letter, with the leading physiologists of the world, and may take ten years to complete.
Psychological Effects
The psychological program, carried out with the co-operation of Dr. F. Lyman Wells, has already been completed and the results recently published.[34] These results must be accepted as the testimony of pure science, free from all bias or even remote suggestion of propaganda. They were based upon experiments with moderate doses of alcohol (30 cubic centimeters, or about 8 teaspoonfuls, and 45 cubic centimeters) upon ten normal subjects, very moderate users of alcohol, and may be summarized as follows:
Lower Levels Spinal Cord
A very simple reflex act, the “knee-jerk,” a nervous mechanism controlled by a center at the lower level of the spinal cord, was markedly depressed, the time of response being increased 10 per cent. and the thickening of the muscles concerned in the act decreased 45 per cent. In some subjects the larger dose, 45 cubic centimeters, practically abolished the knee-jerk.
The eye-lid reflex, elicited by a sudden noise, showed the next largest effect, the time of response being increased 7 per cent. and the degree of movement decreased 19 per cent.
Higher Levels
Other nervous mechanisms, or reflex arcs, at the higher levels of the cord, were next investigated: (1) eye-reaction to suddenly appearing stimulus, and (2) speech reaction to visual word stimuli. Dose A (30 cubic centimeters), accelerated the eye-reaction, while dose B (45 cubic centimeters) positively depressed it, agreeing with the simple reaction experiments of Kraepelin. This was the only instance of acceleration of movement of the voluntary muscles through alcohol, all the other tests showing it to be a consistent depressant. The speech reaction showed a positive depressant effect of 3 per cent.
Memory
Free association of ideas and memory tests were also made, and showed practically no effect from alcohol, but, unfortunately, the smaller dose only was used in these tests.