Foveal Splitting of Compounds and Pseudocompounds using Anaglyphs

Abstract

We investigated the nature of linguistic codes at the earliest moments of visual word recognition by employing red-blue anaglyph glasses to split compounds (e.g., snowball) and pseudocompounds (e.g., cartridge) along the fovea’s vertical meridian. By hypothesis, anaglyphs allowed us to manipulate the role of retinotopic projections during visual processing, whereby word segments were projected to the right or left hemisphere via the ipsilateral or contralateral pathways. Furthermore, this technique allows the embedded words (i.e., constituents) of compounds and pseudocompounds to be presented independently in the visual word form area. Seventy-one participants performed a visual masked lexical decision task, where they made word-nonword judgements. Stimuli were presented for 133 milliseconds either completely in black (both pathways), red/blue (ipsilateral pathways) and blue/red (contralateral pathways). The compounds and pseudocompounds were split into their constituents (legal split) or one letter to the left or to right of the morpheme boundary (illegal split). Compounds varied in the degree of semantic transparency, either transparent (T) or opaque (O), of constituents (e.g., TT, snowball; OT, crowbar; TO, jailbird; OO, hogwash). The accuracy and response times (RTs) to the lexical decision task were analyzed using linear mixed effects models. Results suggest an advantage for words processed through both visual pathways than when they are projected contralaterally (both in accuracy and RTs) and ipsilaterally (in accuracy only). Furthermore, legally split stimuli were judged faster and more accurately than illegal split stimuli regardless of word type. Responses to compounds were more accurate when compared to pseudocompounds. Taken together, these findings suggest that the early visual word recognition system is sensitive to the internal structure of compounds and pseudocompounds, but blind to the semantic contribution of their constituents.