Running head: LEXICAL FEEDBACK Lexical effects on compensation for coarticulation: The ghost of Christmash past

The question of when and how bottom-up input is integrated with top-down knowledge has been debated extensively within cognition and perception, and particularly within language processing. A long running debate about the architecture of the spoken-word recognition system has centered on the locus of lexical effects on phonemic processing: does lexical knowledge influence phoneme perception through feedback, or postperceptually in a purely feedforward system? Elman and McClelland (1988) reported that lexically restored ambiguous phonemes influenced the perception of the following phoneme, supporting models with feedback from lexical to phonemic representations. Subsequently, several authors have argued that these results can be fully accounted for by diphone transitional probabilities in a feedforward system (Cairns et al., 1995; Pitt & McQueen, 1998). We report results strongly favoring the original lexical feedback explanation: lexical effects were present even when transitional probability biases were opposite to those of lexical biases.