Developing a memory representation: Do we visualize or do we "verbalize" objects as we explore them?

Abstract

Participants typically perform better when testing conditions match learning conditions, a phenomenon labeled encoding specificity. Interestingly, recent findings in visuo-haptic object identification violate this principle: participants who learn to recognize objects haptically perform just as well when asked to identify objects by sight as by touch. One possible explanation is that participants who explore objects haptically visualize the objects they explore, creating a multisensory memory trace equally accessible to vision and touch. I evaluated this possibility by asking healthy undergraduate participants to learn to recognize novel objects either by sight or by touch. Participants completed sequences of learning trials where they explore each object, and test trials where they recall the name of each object. During learning trials, some participants were presented with a visual distractor (half of participants viewed letters and the other half viewed nonverbal characters) they had to recognize later, while other participants completed a distractor-less control condition. Consistent with past findings, my results violated encoding specificity for participants who learned to recognize objects haptically. Interestingly however, only the verbal distractors interfered with learning. These results suggest that the creation of memory representation for novel objects is mediated by a verbal code rather than through visualization.