THE EFFECTS OF ATTENTION.
Project Gutenberg EPUB3 edition
James, William
0.214
0.156
21
(Bell-stroke
With noise
0.313
0.499
0.183
16
moderate)
Without noise
0.158
0.206
0.133
20
(Bell-stroke
With noise
0.203
0.295
0.140
19
loud)
"Since, in these experiments, the sound B even with noise made a considerably stronger impression than the sound A without, we must see in the figures a direct influence of the disturbing noise on the process of reaction. This influence is freed from mixture with other factors when the momentary stimulus and the concomitant disturbance appeal to different senses. I chose, to test this, sight and hearing. The momentary signal was an induction-spark leaping from one platinum point to another against a dark background. The steady stimulation was the noise above described.
Spark.
Mean.
Maximum.
Minimum.
No. of Expts.
Without noise
0.222
0.284
0.158
20
With noise
0.300
0.390
0.250
18
"When one reflects that in the experiments with one and the same sense the relative intensity of the signal is always depressed [which by itself is a retarding condition] the amount of retardation in these last observations makes it probable that the disturbing influence upon attention is greater when the stimuli are disparate than when they belong to the same sense. One does not, in fact, find it particularly hard to register immediately, when the bell rings in the midst of the noise; but when the spark is the signal one has a feeling of being coerced, as one turns away from the noise towards it. This fact is immediately connected with other properties of our attention. The effort of the latter is accompanied by various corporeal sensations, according to the sense which is engaged. The innervation which exists during the effort of attention is therefore probably a different one for each sense-organ."[354]