Pickering & Garrod (P&G) put forward the interesting idea that language production relies on forward modeling operating at multiple processing levels. The evidence currently available to substantiate this idea mostly concerns sensorimotor processes and not more abstract linguistic levels (e.g., syntax, semantics, phonology). The predictions that follow from the claim seem too general, in their current form, to guide specific empirical tests.

Covert speech is accompanied by a subjective multisensory experience with auditory and kinaesthetic components. An influential hypothesis states that these sensory percepts result from a simulation of the corresponding motor action that relies on the same internal models recruited for the control of overt speech. This simulationist view raises the question of how it is possible to imagine speech without executing it. In this perspective, we discuss the possible role played by motor inhibition during covert speech production. We suggest that (...) considering covert speech as an inhibited form of overt speech maps naturally to the purported progressive internalization of overt speech during childhood. We further argue that the role of motor inhibition may differ widely across different forms of covert speech and that considering this variety helps reconciling seemingly contradictory findings from the neuroimaging literature. (shrink)

Bilinguals have been shown to perform worse than monolinguals in a variety of verbal tasks. This study investigated this bilingual verbal cost in a large-scale picture-naming study conducted in Spanish. We explored how individual characteristics of the participants and the linguistic properties of the words being spoken influence this performance cost. In particular, we focused on the contributions of lexical frequency and phonological similarity across translations. The naming performance of Spanish-Catalan bilinguals speaking in their dominant and non-dominant language was compared (...) to that of Spanish monolinguals. Single trial naming latencies were analyzed by means of linear mixed models accounting for individual effects at the participant and item level. While decreasing lexical frequency was shown to increase naming latencies in all groups, this variable by itself did not account for the bilingual cost. In turn, our results showed that the bilingual cost disappeared when naming words with high phonological similarity across translations. In short, our results show that frequency of use can play a role in the emergence of the bilingual cost, but that phonological similarity across translations should be regarded as one of the most important variables that determine the bilingual cost in speech production. Low phonological similarity across translations yields worse performance in bilinguals and promotes the bilingual cost in naming performance. The implications of our results for the effect of phonological similarity across translations within the bilingual speech production system are discussed. (shrink)