21 152 154 2 149 174 34 -32 13 160 176 16 150 188 38 -22 1 135 142 7 106 134 28 -21 18 133 126 - 7 100 108 8 -15 23 150 157 7 122 141 19 -12 10 68 145 77 70 148 78 - 1 3 136 144 8 135 135 0 8 20 105 122 17 150 154 4 13 15 172 192 20 140 145 5 15 27 108 114 6 115 101 -14 20 8 113 128 15 131 121 -10 25 28 150 176 26 178 172 - 6 32 2 105 135 30 152 139 -13 43 11 125 120 - 5 155 102 -53 48 14 190 228 38 175 165 -10 48 Av. 133.47 150.6 17.13 134.6 141.8 7.2 9.93 M 15 4 11 75%ile 21.5 21.5 26.75 25%ile 5 -10.75 -16.5 Q 8.25 16.12 21.62 P. E. (distribution) 10.13 17.2 22.07 P. E. (average) +- 2.67 +- 4.53 +- 5.26 Av.=1.89 P. E. M. =2.09 P. E. There were 15 pairs of cases who performed the tapping test at the end of twelve months. Comparison with the 21 pairs after six months yields the following results: 6 months 12 months Average of gains of test group in excess of control - .09 9.93 Median of gains of test group in excess of control 0 11 P. E. of difference +-3.10 +- 5.26 Average in terms of P. E. .03 1.89 Median in terms of P. E. 0 2.09 The gain in the second interval is greater for the tapping test than for any of the tests yet described. After the first six months there is no gain. At the end of ten months the average gain is 9.93, and the median 11 taps per half minute. After six months' interval, 11 of 21 test group cases had lost. At the end of twelve months, only 2 out of 15 had lost. The control group, on the other hand, lost in 11 out of 21 cases after six months, and in 6 out of 15 at the end of twelve months. All but one of the test group cases made more than half of their gain in the second period. Of the control group only 7 cases did this. The variability of gains after 12 months is about equal to the variability at the end of six months.