Page:Mind (Old Series) Volume 11.djvu/536

 THE TIME TAKEN UP BY CEEEBRAL OPERATIONS. 535 TABLE XLI. Concentrated. Distracted. B C B C R R' R , R' R R' R R' White Surface. 4. IV 192 196 186 192 194 193 191 194 236 235 230 246 234 237 231 249 333 250 244 239 321 233 234 239 273 256 234 246 278 254 229 248 5 6 A 191 193 237 . 238 266 257 252 252 AV 13 6 13 10 38 23 16 9 Letters. 4. IV 334 336 335 333 331 335 333 337 336 333 395 397 404 395 410 398 402 410 397 408 387 371 373 343 340 388 366 377 350 339 441 403 432 422 427 442 411 435 418 426 5 6 7 A 334 335 400 403 363 364 425 426 AV 29 20 21 13 33 20 26 16 As I have given throughout this paper the dates on which the series were made and have not omitted any series, the results of continued Practice can be studied to advantage. B and C had previously had considerable practice in making simple reactions, but none in the other processes here considered. In the twenty series of reactions on light (Table I.) made during a period of six months, no reduction in the time is to be noticed. B's reaction- time was however shorter in 1884-5 than in 1883-4, as can be seen from Table VI., where his times, especially for light, are consider- ably longer than C's. I repeated at the close of the investigation the determinations made at the beginning in which the observer reacted on one of a number of colours, letters or words (the results are given in Tables XIX., XXIV., XXVII), and found that the times had become shorter. I give the decrease in time. B Colours 28 Letters 50 Words .. ...54 C 20 25 35