Abstract
Visual words and faces have very different properties, words being two-dimensional high-contrast binary stimuli and faces having complex mobile three-dimensional shapes. However, they are both visual stimuli for which humans have high expertise, and both activate similar cerebral networks (albeit with opposing hemispheric asymmetries), raising the possibility that they might share common perceptual mechanisms and effects. In the present study we examine word processing for one prominent effect described in face processing, the inversion effect. To capture the effect of expertise, we compared recognition for familiar and unfamiliar languages. To determine if stimulus variability played a role, we also compared computerized font and handwriting. We recruited two groups of 20 subjects, one fluent in Farsi and one in Punjabi, with neither familiar with the other language. Stimuli were single words of 5-7 letters in length, in one of 6 handwriting or 6 font styles, shown either upright or inverted. Subjects performed a three-alternative match-to-sample task, with 432 trials total. In addition, subjects performed the Cambridge Face Memory Test (CFMT). Subjects had higher accuracy and faster reaction times with the familiar language, and with computerized font. There was a word inversion effect for the familiar but not the unfamiliar script. The inversion effect for accuracy was almost twice as large for handwriting than computerized font. Performance with the inverted familiar language was still superior to that with the unfamiliar language, indicating that language familiarity still facilitates the processing of inverted stimuli. Word inversion effects did not correlate with face inversion effects on the CFMT. We conclude that experience does generate a word inversion effect, and that this effect is greater for less regular script, when reading requires generalization across natural variations in handwriting.