By means of Motokawa's method of electric flicker the authors examined changes in electrie filicker values (EFV) of 5 healthy males due to loads with and without oral administratin of Thioctic acid (10mg) one hour in advance. As loads, mascular labor, mental work, alcohol drinking, and deep breathing of air were chosen. 1) As muscular labor, step-tests were taken. The step test continued for 15 minutes, the rate of going up and down the two steps (each 25 cm high) being 12 per minute. EFV obtained just after such test with administration of Thioctic acid showed only slight increase, while that with out Thioctioc acid showed remarkable increase. 2) As mental work, the authors used a method of concentrative attention lasting 15 minute. The method was as follows; Five small lamps were lighted by the experimenter in random order, and the subject was requested to press a key only when two lamps were lighted simulataneously. The interval between successive flashes was 1 second. EFV obtained just after this performance with adminiration Thioctic acid was remarkably smaller than EFV without it and recovery of the former was faster than of the latter. 3) EFV obtained after drinking 15∼40% alcohol (100cc∼40cc) increased remarkably, but EFV obtained after alcohol drinking combined with Thioctic acid administration did not show any marked increase and returned rapidly to the initial value. 4) By deep breathings of air (20∼22 times per minute), EFV increased remarkably, regardless of whether the Thioctic acid has been administered or not. Summarizing the above results, it is stated that administration of Thioctic acid in advance is effective in reducing fatigue caused by mascular labor, mental work and alcohol drinking, but not effective in preventing the effect of acapnia caused by deep breathing of air.
