Smooth Pursuit in The Absence of A Visual Target
Performing smooth pursuit without a moving visual stimulus is difficult, and typically results in a series of saccades. However, pursuit without a visible target is possible under some particular conditions, that show the importance of high-level functions in smooth pursuit maintenance. If you know which way a target will move, or know the target trajectory (because it is periodic for instance), you can initiate pursuit before the target motion actually starts, especially if you know exactly when the motion will start. It is also possible to maintain pursuit if a target momentarily disappears, especially if the target appears to be occluded by a larger object. Under conditions in which there is no visual stimulation (in total darkness), we can still perform smooth pursuit eye movements with the help of a proprioceptive motion signal (e.g. your moving finger).
Read more about this topic: Smooth Pursuit
Famous quotes containing the words smooth, pursuit, absence, visual and/or target:
“Black water, smooth above the weir
Like starry velvet in the night,
Though ruffled once, would soon appear
The same as ever to the sight.”
—Edwin Arlington Robinson (1869–1935)
“I know of no pursuit in which more real and important services can be rendered to any country than by improving its agriculture, its breed of useful animals, and other branches of a husbandman’s cares.”
—George Washington (1732–1799)
“We have good reason to believe that memories of early childhood do not persist in consciousness because of the absence or fragmentary character of language covering this period. Words serve as fixatives for mental images. . . . Even at the end of the second year of life when word tags exist for a number of objects in the child’s life, these words are discrete and do not yet bind together the parts of an experience or organize them in a way that can produce a coherent memory.”
—Selma H. Fraiberg (20th century)
“To write well, to have style ... is to paint. The master faculty of style is therefore the visual memory. If a writer does not see what he describes—countrysides and figures, movements and gestures—how could he have a style, that is originality?”
—Rémy De Gourmont (1858–1915)
“All of women’s aspirations—whether for education, work, or any form of self-determination—ultimately rest on their ability to decide whether and when to bear children. For this reason, reproductive freedom has always been the most popular item in each of the successive feminist agendas—and the most heavily assaulted target of each backlash.”
—Susan Faludi (20th century)