3. Since it is practically impossible to speak continuously without variation of accent, the following method was adopted to avoid irregular variations: either three or four syllables were united into a measure, and thus either the 1st, 4th, 7th, or the 1st, 5th, 9th … syllables were pronounced with a slight accent. Stressing of the voice was otherwise, as far as possible, avoided.
4. After the learning of each separate series a pause of 15 seconds was made, and used for the tabulation of results. Then the following series of the same test was immediately taken up.
5. During the process of learning, the purpose of reaching the desired goal as soon as possible was kept in mind as much as was feasible. Thus, to the limited degree to which conscious resolve is of influence here, the attempt was made to keep the attention concentrated on the tiresome task and its purpose. It goes without saying that care was taken to keep away all outer disturbances in order to make possible the attainment of this aim. The smaller distractions caused by carrying on the test in various surroundings were also avoided as far as that could be done.
6. There was no attempt to connect the nonsense syllables by the invention of special associations of the mnemotechnik type; learning was carried on solely by the influence of the mere repetitions upon the natural memory. As I do not possess the least practical knowledge of the mnemotechnical devices, the fulfillment of this condition offered no difficulty to me.
7. Finally and chiefly, care was taken that the objective conditions of life during the period of the tests were so controlled as to eliminate too great changes or irregularities. Of course, since the tests extended over many months, this was possible only to a limited extent. But, even so, the attempt was made to conduct, under as similar conditions of life as possible, those tests the results of which were to be directly compared. In particular the activity immediately preceding the test was kept as constant in character as was possible. Since the mental as well as the physical condition of man is subject to an evident periodicity of 24 hours, it was taken for granted that like experimental conditions are obtainable only at like times of day. However, in order to carry out more than one test in a given day, different experiments were occasionally carried on together