Saccade

A Saccade is a quick, simultaneous movement of both eyes between two or more phases of fixation in the same direction. In contrast, in smooth pursuit movements, the eyes move smoothly instead of rapidly. The phenomenon can be associated with a shift in frequency of an emitted signal or a momentary interruption of it. It is a type of eye movement that assists in scanning the surrounding environment.

Physiology

The speed of movement during each saccade cannot be controlled; the eyes move as fast as they are able. The velocity of the saccade to an extent is related to the amplitude of the movement; when the saccade amplitude increases, the peak saccadic speed increases.

Clinical significance

Saccades are essential for visual perception as they allow the eyes to rapidly move and fixate onto different objects in the visual field. Abnormalities in saccadic eye movements can lead to a variety of visual and cognitive deficits.

See also

• Eye movement in reading
• Eye movement in music reading
• Fixation (visual)
• Superior colliculus
• Optokinetic reflex
• Nystagmus
• Microsaccade
• Express saccade
• Inhibition of return
• Chronostasis
• Saccadic masking
• Saccadic suppression of image displacement
• Transsaccadic memory
• Visual perception
• Visual system

Saccade

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  Szakkad
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  This shows a recording of the eye movements of a participant looking freely at a picture
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  Saccadic main sequence