Lobsien made tests similar to those of Netschajeff,[28] with modifications for greater accuracy, upon 238 boys and 224 girls from nine to fourteen and a half years of age. The preceding tables show the development of the various kinds of memory for boys and girls:
Age. Objects Noises Number Visual Acoustic Touch Feeling Sounds Concepts Concepts Concepts Concepts
13-14-1/2 92.56 71.89 80.67 73.00 74.78 75.33 75.44 40.56 12-13 76.45 57.38 72.33 69.67 64.89 73.67 58.67 37.87 11-12 89.78 57.19 70.22 59.67 63.00 73.33 55.33 19.99 10-11 87.12 55.33 49.33 55.11 48.44 57.11 38.33 12.44 9-10 64.00 53.33 49.09 46.58 43.78 43.67 27.22 7.22
Normal 82.2 59.02 64.8 60.6 59.4 64.2 31.2 24.0 value.
13-14-1/2 99.56 82.67 87.22 96.67 71.44 82.00 70.22 41.33 12-13 92.89 75.56 74.89 77.22 63.11 74.67 67.33 34.89 11-12 94.00 56.00 73.56 72.78 72.11 70.89 73.33 28.22 10-11 75.78 46.22 62.44 56.22 54.78 58.78 43.22 10.44 9-10 89.33 46.22 50.44 54.22 38.22 51.11 32.89 6.89
Normal 91.4 62.2 71.8 71.0 60.2 67.2 59.4 23.8 value.
The table for boys shows in the fourteenth year a marked increase of memory for objects, noises, and feelings, especially as compared with the marked relative decline the preceding year, when there was a decided increase in visual concepts and senseless sounds. The twelfth year shows the greatest increase in number memory, acoustic impressions, touch, and feeling. The tenth and eleventh years show marked increase of memory for objects and their names. Thus the increase in the strength of memory is by no means the same year by year, but progress focuses on some forms and others are neglected. Hence each type of memory shows an almost regular increase and decrease in relative strength.
The table for girls shown marked increase of all memory forms about the twelfth year. This relative increase is exceeded only in the fourteenth year for visual concepts. The thirteenth year shows the greatest increase for sounds and a remarkable regression for objects in passing from the lowest to the next grade above.
In the accuracy of reproducing the order of impressions, girls much exceeded boys at all ages. For seen object, their accuracy was twice that of boys, the boys excelling in order only in number. In general, ability to reproduce a series of impressions increases and decreases with the power to reproduce in any order, but by no means in direct proportion to it. The effect of the last member in a series by a purely mechanical reproduction is best in boys. The range and energy of reproduction is far higher than ordered sequence. In general girls slightly exceed boys in recalling numbers, touch concepts, and sounds, and largely exceed in recalling feeling concepts, real things and visual concept.