On the other hand, there seems to be nothing in the experiment which
shows that the images of the three holes were present to consciousness
just during the movement, rather than immediately thereafter. A
central mechanism of inhibition, such as Exner mentions, might
condition a central anæsthesia during movement, although the
functioning of the retina should remain unaltered. Such a central
anæsthesia would just as well account for the phenomena which have
been enumerated. The three luminous images could be supposed to remain
unmodified for a finite interval as positive after-images, and as such
first to appear in consciousness. Inasmuch as 'the arc of eye
movements was 4.7°' only, the time would be too brief to make possible
any reliable judgment as to whether the three holes were seen during
or just after the eye-movement. With this point in view, the writer
repeated the experiment of Dodge, and found indeed nothing which gave
a hint as to the exact time when the images emerged in consciousness.
The results of Dodge were otherwise entirely confirmed.


II. THE PHENOMENON OF 'FALSELY LOCALIZED AFTER-IMAGES.'


A further fact suggestive of anæsthesia during movement comes from an
unexpected source. While walking in the street of an evening, if one
fixates for a moment some bright light and then quickly turns the eye
away, one will observe that a luminous streak seems to dart out from
the light and to shoot away in either of two directions, either in the
same direction as that in which the eye moved, or in just the
opposite. If the eye makes only a slight movement, say of 5°, the
streak jumps with the eye; but if the eye sweeps through a rather