| 释义 |
saccade|sakad, səˈkɑːd|
[Fr.]
a. A jerk or jerky movement (in various specific applications).
1727–41Chambers Cycl., Saccade, in the manage, a jerk or violent check which the rider gives his horse, by drawing both the reins very suddenly. 1876Stainer & Barrett Dict. Mus. Terms, Saccade (Fr.), strong pressure of a violin bow against the strings, which by forcing them to a level enables the player to produce three or four notes simultaneously. 1897Syd. Soc. Lex., Saccade, the involuntary jerking movement in the act of swallowing.
b. A brief, rapid movement of the eye from one position of rest to another, whether voluntary (as in reading) or involuntary (as when a point is fixated).
1953Jrnl. Optical Soc. Amer. XLIII. 495/2 These [types of eye movement] include relatively large slow waves, saccades, and slow drifts of fixation. 1962Ibid. LII. 571/2 The eye does not move continuously along a line of print in reading, but executes a regular alternation of rapid jumps, called saccades, and fixational pauses. 1967New Scientist 20 Apr. 156/1 Apart from a rapid trembling which plays a part in the mechanism of perception itself, there are two main types of eye-movement: slow ‘drifts’ away from the target image, and rapid jerks or ‘saccades’ tending to recentre it. 1971Sci. Amer. June 35/2 Each saccade leads to a new fixation on a different point in the visual field. Typically there are two or three saccades per second. 1974Nature 22 Mar. 308/3 Some observers can learn to suppress small saccades completely, without decreasing the accuracy of fixation or the visibility of the target. |