Novel Popout: Effects of Field Unitization and Exposure Duration

Observers who glimpsed 4-word arrays were probed for the locations of particular words. Some words, called 'familiar', appeared in many arrays; and others, called 'novel', appeared in only one. Studies conducted in the first year showed that familiar words are more localizable than novel words when they are not mixed together in the same array but that this difference is diminished, and often reversed, when a single novel word is arrayed with 3 familiar words. Thus, familiar arrays are more perceptible than novel arrays, but novel words popout from familiar fields. Nine new studies were conducted in the second year. Experiments 1-4 examined properties of the familiar fields. Nine new studies were conducted in the second year. Experiments 1-4 examined properties of the familiar fields from which novel words popout. Exp. 1 and 2 showed that single prior presentation of either the individual words comprising the familiar field or the field as a whole does not suffice to produce robust novel popout. Exp. 3 demonstrated that, whereas relatively few repetitions of an array are necessary to render it more preceptible than a novel array, relatively many repetitions are necessary to yield novel popout. In Exp. 4, all the familiar words in an array had been presented many times in a prior familiarization phase. However, these words has either always or never before appeared together. That is, familiar fields were either unitized or nonunitized. Novel words popped out only from utilized familiar fields. We attribute novel popout to the rapid, automatic orientation of attention to a local perturbation of an otherwise unitized perceptual field.