Semantic word priming in the absence of eye fixations: relative contributions of overt and covert attention.

In the present study, we investigated the role of covert and overt attention in word identification. In repetition and semantic priming paradigms, prime words were followed by a probe for lexical decision. To make the primes available only to covert attention, we presented them for 150 msec, parafoveally (2.2 degrees away from fixation), and under gaze-contingent foveal masking. To make the primes available to overt attention, we presented them for 150 msec, at fixation, with no masking. Results showed both repetition and semantic priming in the absence of eye fixations on the primes: There was facilitation for identical and semantically related probe words, relative to an unrelated prime-probe condition. This revealed that both word form and meaning can be processed by covert attention alone. The pattern of relative contributions of covert (approximately 25%) and overt (approximately 75%) attention was similar for repetition and semantic priming.