Transposed-letter Research Articles

The time course of orthographic and phonological code activation.

The present study used event-related potentials (ERPs) to examine the time course of orthographic and phonological priming in the masked priming paradigm. Participants monitored visual target words for occasional animal names, and ERPs to nonanimal critical items were recorded. These critical items were preceded by different types of primes: Orthographic priming was examined using transposed-letter (TL) primes (e.g., barin-BRAIN) and their controls (e.g., bosin-BRAIN); phonological priming was examined using pseudohomophone primes (e.g., brane-BRAIN) and their controls (e.g., brant-BRAIN). Both manipulations modulated the N250 ERP component, which is hypothesized to reflect sublexical processing during visual word recognition. Orthographic (TL) priming and phonological (pseudohomophone) priming were found to have distinct topographical distributions and different timing, with orthographic effects arising earlier than phonological effects.

Do Transposed-Letter Similarity Effects Occur at a Prelexical Phonological Level?

Nonwords created by transposing two letters (e.g., RELOVUTION) are very effective at activating the lexical representation of their base words (Perea & Lupker, 2004). In the present study, we examined whether the nature of transposed-letter (TL) similarity effects was purely orthographic or whether it could also have a phonological component. Specifically, we examined transposed-letter similarity effects for nonwords created by transposing two nonadjacent letters (e.g., relovución-REVOLUCION) in a masked form priming experiment using the lexical decision task (Experiment 1). The controls were (a) a pseudohomophone of the transposed-letter prime (relobución-REVOLUCION; note that B and V are pronounced as /b/ in Spanish) or (b) an orthographic control (relodución-REVOLUCION). Results showed a similar advantage of the TL nonword condition over the phonological and the orthographic control conditions. Experiment 2 showed a masked phonological priming effect when the letter positions in the prime were in the right order. In a third experiment, using a single-presentation lexical decision task, TL nonwords produced longer latencies than the orthographic and phonological controls, whereas there was only a small phonological effect restricted to the error data. These results suggest that TL similarity effects are orthographic--rather than phonological--in nature.

Can CANISO activate CASINO? Transposed-letter similarity effects with nonadjacent letter positions

Nonwords created by transposing two adjacent letters (i.e., transposed-letter (TL) nonwords like jugde) are very effective at activating the lexical representation of their base words. This fact poses problems for most computational models of word recognition (e.g., the interactive-activation model and its extensions), which assume that exact letter positions are rapidly coded during the word recognition process. To examine the scope of TL similarity effects further, we asked whether TL similarity effects occur for nonwords created by exchanging two nonadjacent letters (e.g., caniso- CASINO) in three masked form priming experiments using the lexical decision task. The two nonadjacent transposed letters were consonants in Experiment 1 (e.g., caniso- CASINO), vowels in Experiment 2 ( anamil-ANIMAL) and both consonants and vowels in Experiment 3. Results showed that nonadjacent TL primes produce priming effects (in comparison to orthographic controls, e.g., caviro- CASINO), however, only when the transposed letters are consonants. In a final experiment we examined latencies for nonwords created by nonadjacent transpositions of consonants versus vowels in a lexical decision task. Both types of nonwords produced longer latencies than matched controls, with consonant TL nonwords being more difficult than vowel TL nonwords. The implications of these findings for models having “position-specific” coding schemes as well as for models proposing alternative coding schemes are discussed.

Does jugde activate COURT? Transposed-letter similarity effects in masked associative priming.

Transposed-letter (TL) nonwords (e.g., jugde) can be easily misperceived as words, a fact that is somewhat inconsistent with the letter-position-coding schemes employed by most current models of visual word recognition. To examine this issue further, we conducted four masked semantic/associative priming experiments, using a lexical decision task. In Experiment 1, the related primes could be words, TL-internal nonwords, or replacement-letter (RL) nonwords (e.g., judge, jugde, or judpe, respectively; the target would be COURT). Relative to an unrelated condition, masked TL-internal primes produced a significant semantic/associative priming effect, an effect that was only slightly smaller than the priming effect for word primes. No effect, however, was observed for RL-nonword primes. In Experiment 2, the TL-nonword primes were created by switching the two final letters of the primes (e.g., judeg). The results again showed a semantic/associative priming effect for word primes, but not for TL-final nonword primes or for RL-nonword primes. Experiment 3 replicated the associative/semantic priming effect for TL-internal nonword primes, with, again, no effect for TL-final nonword primes. Finally, Experiment 4 again failed to yield a priming effect for TL-final nonword primes. The implications of these results for the choice of a letter-position-coding scheme in visual word recognition models are discussed.

Lexical Retrieval and Selection Processes: Effects of Transposed-Letter Confusability

Three experiments investigated performance for words which differ from another word only by the transposition of two letters (e.g.,salt, slat). In Experiment 1, high frequency words from transposed-letter (TL) confusable pairs were responded to more slowly than carefully matched control words in both the lexical decision and word naming task. Low frequency TL words were responded to less accurately than control words in the naming but not the lexical decision task. Experiment 2 replicated the naming data of Experiment 1 and also revealed that naming accuracy for TL word targets was reduced when they were preceded by a brief masked presentation of their confusable mate. Experiment 3 provided a third replication of the impaired naming performance for TL target words and demonstrated that the effect was insensitive to concurrent dual task demands. These TL confusability effects provide strong constraints that can contribute to evaluation and specification of current models of visual word recognition.