Wendy S. Francis

Convergent cortical representation of semantic processing in bilinguals

This study examined whether semantic processes in two languages (English and Spanish) are mediated by a common neural system in fluent bilinguals who acquired their second language years after acquiring their first language. Functional magnetic resonance imaging was performed while bilingual participants made semantic and nonsemantic decisions about words in Spanish and English. There was greater activation for semantic relative to nonsemantic decisions in left and right frontal regions, with greater left frontal activation. The locations of activations were similar for both languages, and no differences were found when semantic decisions for English and Spanish words were compared directly. These results demonstrate a shared frontal lobe system for semantic analysis of the languages and are consistent with cognitive research on bilingualism indicating that the two languages of a bilingual person access a common semantic system.

Cognitive integration of language and memory in bilinguals: Semantic representation.

Understanding cognitive research on the integration of 2 languages in bilingual memory is difficult because of the different terminology, methodology, analysis, and interpretation strategies that scholars with different backgrounds bring to the research. These studies can be usefully categorized on 2 dimensions: memory for verbal experience versus linguistic knowledge, and systemwise versus pairwise issues. Experimental findings in this area converge on the conclusion that at the word meaning/conceptual level, both episodic and linguistic memory can be characterized as shared at the systems level and at least partly shared at the pairwise translation-equivalent level. Interpretation problems that stem from weak hypothesis testing structure and from covert translation can be minimized by using appropriate design and analysis techniques.

Convergent behavioral and neuropsychological evidence for a distinction between identification and production forms of repetition priming

Four experiments examined a distinction between kinds of repetition priming which involve either the identification of the form or meaning of a stimulus or the production of a response on the basis of a cue. Patients with Alzheimers disease had intact priming on picture-naming and category-exemplar identification tasks and impaired priming on word-stem completion and category-exemplar production tasks. Division of study-phase attention in healthy participants reduced priming on word-stem completion and category-exemplar production tasks but not on picture-naming and category-exemplar identification tasks. The parallel dissociations in normal and abnormal memory cannot be explained by implicit-explicit or perceptual-conceptual distinctions but are explained by an identification-production distinction. There may be separable cognitive and neural bases for implicit modulation of identification and production forms of knowledge.

Repetition priming in picture naming and translation depends on shared processes and their difficulty: Evidence from Spanish-English bilinguals

Two experiments with highly fluent Spanish-English bilinguals examined repetition priming of picture identification and word retrieval in picture naming. In Experiment 1, between-language priming of picture naming was symmetric, but within-language priming was stronger in the nondominant language. In Experiment 2, priming between picture naming and translation was symmetric within both the dominant language and the nondominant language, but priming was stronger in the nondominant language. A mathematical model required only 3 process parameters to explain the pattern of priming across 8 conditions. These results indicate that shared processes are the basis of priming, that difficulty influences priming only at the process level, and that translation in both directions is concept mediated in fluent bilinguals.

Concept mediation in trilingual translation: evidence from response time and repetition priming patterns.

Translation responses to individual words were elicited from 48 English-Spanish-French trilinguals, who translated in six directions at study and two directions at test. Patterns of translation response times and error rates at study reflected the relative proficiency of the trilinguals in comprehension and production of their three languages. At test, repeated items were translated more quickly than new items, with the strongest priming effects occurring for identical repetitions. Repetition priming was also substantial when only the stimulus language or only the response language matched from study to test, implying that repeated comprehension and production processes contribute to priming in translation. Patterns of response times and repetition priming indicate that translation in all directions involved conceptual access. Additive patterns in response time asymmetries and repetition priming were consistent with the treatment of word comprehension and production processes of translation as independent.

Decomposition of repetition priming components in picture naming.

Cognitive mechanisms underlying repetition priming in picture naming were decomposed in several experiments. Sets of encoding manipulations meant to selectively prime or reduce priming in object identification or word production components of picture naming were combined factorially to dissociate processes underlying priming in picture naming. Experiments 1, 2, and 3 were conducted with Spanish-English bilingual participants and bilingual materials. Experiments 4, 5A, and 5B were single-language experiments in English or Spanish. A simple process model was used to formalize the theoretical predictions and test them across all experiments simultaneously. Object identification and word production processes were selectively influenced in an additive manner, which suggests that the 2 sets of processes are independent and sequential. The patterns of facilitation support a quantitative model of transfer-appropriate processing in which shared processes from encoding to test are the causal basis and speeded processes are the mechanism of facilitation.

The consequences of language proficiency and difficulty of lexical access for translation performance and priming

Repetition priming was used to assess how proficiency and the ease or difficulty of lexical access influence bilingual translation. Two experiments, conducted at different universities with different Spanish–English bilingual populations and materials, showed repetition priming in word translation for same-direction and different-direction repetitions. Experiment 1, conducted in an English-dominant environment, revealed an effect of translation direction but not of direction match, whereas Experiment 2, conducted in a more balanced bilingual environment, showed an effect of direction match but not of translation direction. A combined analysis on the items common to both studies revealed that bilingual proficiency was negatively associated with response time (RT), priming, and the degree of translation asymmetry in RTs and priming. An item analysis showed that item difficulty was positively associated with RTs, priming, and the benefit of same-direction over different-direction repetition. Thus, although both participant accuracy and item accuracy are indices of learning, they have distinct effects on translation RTs and on the learning that is captured by the repetition-priming paradigm.

Repetition priming endurance in picture naming and translation: Contributions of component processes

The processes contributing to the durability of repetition priming in picture naming and its decline across a week were assessed in two experiments with Spanish—English bilinguals. In Experiment 1, both picture identification and word retrieval processes of picture naming exhibited facilitation after a week. Word retrieval priming declined substantially relative to a 10-min retention interval, but picture identification priming remained stable. In Experiment 2, word translation exhibited repetition priming after a week. Decreased word retrieval priming accounted for the attenuation of translation priming relative to a 10-min interval, whereas word comprehension priming remained stable. A linear process model was used to formalize and test key hypotheses and to clarify the influences of component processes and retention interval on repetition priming.

Repetition Priming in Picture Naming: Sustained Learning through the Speeding of Multiple Processes

Picture naming has been used by vision researchers to study object identification, by language researchers to study word production, and by memory researchers to study implicit memory. Response times for naming repeated pictures decrease with successive repetitions. Repetition priming in picture naming involves an implicit, nonhippocampal form of memory. In this review, the processes speeded with repetition are decomposed, the time course of the effect is characterized, the factors affecting the magnitude of priming are enumerated, and possible mechanisms of priming are evaluated. Both behavioral response time and neuroimaging studies are considered. The processes that are speeded with repetition include high-level object identification and word production processes, but not low-level visual processes or articulation. Repetition priming lasts for at least several weeks and follows a typical forgetting function. The mechanism of priming is concluded to be speeded completion of the component processes of picture naming.

Bilingual recognition memory: Stronger performance but weaker levels-of-processing effects in the less fluent language

The effects of bilingual proficiency on recognition memory were examined in an experiment with Spanish–English bilinguals. Participants learned lists of words in English and Spanish under shallow- and deep-encoding conditions. Overall, hit rates were higher, discrimination greater, and response times shorter in the nondominant language, consistent with effects previously observed for lower frequency words. Levels-of-processing effects in hit rates, discrimination, and response time were stronger in the dominant language. Specifically, with shallow encoding, the advantage for the nondominant language was larger than with deep encoding. The results support the idea that memory performance in the nondominant language is impacted by both the greater demand for cognitive resources and the lower familiarity of the words.