Description
Picture-Word Interference (PWI) paradigms involve naming pictures in the presence of distractor words. Priming a picture by the expected name (e.g. the word CAT followed by a picture of a cat) usually results in faster naming times when compared to naming a picture preceded by an unrelated word (e.g., KEY followed by a picture of a cat). Priming a picture by a semantically related word (e.g., DOG followed by a picture of a cat) results in slower picture naming times. The Response Exclusion Hypothesis (REH) posits that this semantic interference results from competition for articulation between the spoken word DOG and the spoken word CAT as opposed to competition for lexical access. Here English – American Sign Language (ASL) bimodal bilinguals (20 hearing and 20 deaf) are asked to sign, rather than speak the names of the pictures thus eliminating competition between the oral articulators of the English prime word and the manual articulators of ASL. Event-Related Potentials (ERPs) were recorded and time-locked to the onset of each picture stimulus. Manual reaction times (RTs) were measured from picture onset to liftoff of the signing hand from the spacebar on the keyboard. ANOVAs were performed on ERP component amplitudes and t-tests were performed on RTs to determine any significant differences between prime conditions. Faster RTs and attenuated ERP component amplitudes were observed for both deaf and hearing signers to translation targets compared to unrelated target pictures. For semantically related compared to unrelated targets, the hearing signers displayed no RT differences while the deaf signers showed faster RTs to semantically related targets. Attenuated ERP amplitudes to semantically related compared to unrelated targets were seen in both groups, though the hearing signers also displayed a late posterior positivity to semantically related targets that was not significant in the translation condition or in the deaf signers. The semantic interference effect typically seen in unimodal PWI paradigms was not observed in bimodal bilinguals. In fact, deaf bimodal bilinguals show evidence of semantic facilitation. Because no competition for articulation exists between bimodal bilingual’s two languages, these findings support the REH for semantic interference in the PWI paradigm.
