ABSTRACT
H uman learning in the visual domain is best understood as a continuum, characterized by the depth and degree to which a stimulus is encoded, the specic cognitive operations that are engaged, and the distinct neural structures that are recruited. At one end of the continuum, a single presentation of a visual stimulus-so brief as to elude the perceptual awareness of the observercan nevertheless alter one’s subsequent perceptions. For example, studies show that a word stimulus not consciously perceived by the participant can nonetheless facilitate subsequent perceptions of that word (Jacoby & Hayman, 1987). At the other end of the continuum of human learning, changes in perception can result from explicit, purposeful training that occurs over weeks, months, or even a lifetime of practice and experience. For example, farmers learn to differentiate the sex of chickens; musicians learn to distinguish the notes, chords, and instrumental voices in a musical piece; and tennis players learn to anticipate the placement of upcoming shots. In such real-world domains of expertise, the acquisition of information and the renement of knowledge involve changes in perception, memory, semantics, inference generation, and motor actions (Ericsson, Krampe, & TeschRomer, 1993; Palmeri, Wong, & Gauthier, 2004).
