Biomedical subjects

A E Hernandez

Publications and source records attributed to A E Hernandez.

6 recordsLinked to original sources

PubMed2001

Language switching and language representation in Spanish-English bilinguals: an fMRI study.

The current experiment was designed to investigate the nature of cognitive control in within- and between-language switching in bilingual participants. To examine the neural substrate of language switching we used functional magnetic resonance imaging (fMRI) as subjects named pictures in one language only or switched between languages. Participants were also asked to name (only in English) a separate set of pictures as either the actions or the objects depicted or to switch between these two types of responses on each subsequent picture. Picture naming compared to rest revealed activation in the dorsolateral prefrontal cortex, which extended down into Broca's area in the left hemisphere. There were no differences in the activation pattern for each language. English and Spanish both activated overlapping areas of the brain. Similarly, there was no difference in activation for naming actions or objects in English. However, there was increased intensity of activation in the dorsolateral prefrontal cortex for switching between languages relative to no-switching, an effect which was not observed for naming of actions or objects in English. We suggest that the dorsolateral prefrontal cortex serves to attenuate interference that results from having to actively enhance and suppress two languages in alternation. These results are consistent with the view that switching between languages involves increased general executive processing. Finally, our results are consistent with the view that different languages are represented in overlapping areas of the brain in early bilinguals.

Adult↗

PubMed2000

In search of the language switch: An fMRI study of picture naming in Spanish-English bilinguals.

For many years, researchers investigating the brain bases of bilingualism have concentrated on two basic questions. The first concerns the nature of language representation. That is, are a bilinguals' two languages represented in distinct or overlapping areas of the brain. The second basic question in the neuropsychology of bilingualism concerns the neural correlates of language switching, that is, the areas that are active when bilinguals switch from one language to the other. Performance between single-language and dual-language picture naming was compared in a group of six Spanish-English bilinguals using behavioral measures and functional magnetic resonance imaging. Participants showed slower reaction times and increased activation in the dorsolateral prefrontal cortex in the mixed language condition relative to single language condition. There was no evidence that each language was represented in different areas of the brain. Results are consistent with the view that language switching is a part of a general executive attentional system and that languages are represented in overlapping areas of the brain in early bilinguals.

Adult↗

PubMed1999

Balancing bilinguals: lexical-semantic production and cognitive processing in children learning Spanish and English.

The present study investigated developmental changes in lexical production skills in early sequential bilinguals, in both Spanish (L1) and English (L2), exploring the effects of age, years of experience, and basic-level cognitive processing (specifically the ability to resist interference) within a timed picture-naming task. To assess resistance to interference, naming was compared in low competition (blocked-single language) vs. high competition (mixed-alternating language) conditions. Participants were 100 individuals, 20 at each of 5 different age levels (5-7, 8-10, 11-13, 14-16, & young adults). All had learned Spanish as a first language in the home, with formal English experience beginning at 5 years. Gains were made in both languages across age. However, there was a developmental crossover from Spanish dominance in the youngest children, through a period of relatively balanced Spanish and English skills in middle childhood, culminating in a clear pattern of English dominance among adolescents and young adults. Although all groups experienced a greater slowing of response times in the mixed-language condition relative to the blocked-language condition, developmental changes in the pattern of speed-accuracy trade-offs in the mixed condition can be interpreted to reflect a change in the ability to resist cognitive interference during word production.

Adolescent↗

PubMed1998

Bilingual performance on the boston naming test: preliminary norms in Spanish and English.

A total of 100 young educated bilingual adults were administered the Boston Naming Test (BNT) (Kaplan, Goodglass, & Weintraub, 1983) in both Spanish and English. Three group performance scores were obtained: English only, Spanish only, and a composite score indicating the total number of items correctly named independent of language. The scores for the entire group were significantly greater in English than in Spanish. An additional set of analyses explored individual differences in picture naming performance across the two languages as measured by the BNT. For a subset of the larger group (n = 25) there were significant differences in composite over single language scoring, but no significant differences between Spanish and English. Item analyses of correct responses were conducted in both languages to explore the construct validity of the standardized administration of the BNT with this population. There was much greater variability in responses over the Spanish items for this bilingual group. The results of a correlation analysis of information obtained from the initial questionnaire with the BNT scores in each language is also reported. The practical implications of this preliminary bilingual BNT normative data are discussed.

Adolescent↗

PubMed1998

Bienestar: a diabetes risk-factor prevention program.

The Bienester Health Program, a diabetes risk-factor prevention pilot program, targeted fourth grade Mexican American children. The primary goals are to decrease the two established risk factors for diabetes--overweight and dietary fats. Since the health program is based on Social Cognitive Theory, on social systems structure, and on culturally relevant material, it considers the child's social systems on both its health program and process evaluation. Learning activities were developed for four social systems that potentially influence children's health behaviors (parent, classroom, school cafeteria, and after-school care). Preliminary results show that the Bienestar Health Program significantly decreased dietary fat, increased fruit and vegetable servings, and increased diabetes health knowledge.

Attitude to Health↗

PubMed1996

Processing across the language boundary: a cross-modal priming study of Spanish-English bilinguals.

A cross-modal naming paradigm was used to assess within- and between-language sentential priming in Spanish-English bilinguals. The paradigm used single-language auditory texts with visual target words under normal, visually degraded, speeded, and delayed naming conditions. Cross-language priming was always observed when the target language was predictable (in the blocked condition), even under speeded conditions. When the target language was unpredictable (in the mixed condition), cross-language priming was observed only when response was delayed (delayed naming) and under a subset of conditions when word recognition was delayed (visual degradation). Results are compatible with the idea that cross-language priming in a sentence context is more likely to involve the use of expectations, strategic processes, or both that allow bilinguals to tune themselves to external conditions. There are enough exceptions to the general rule, however, to warrant a reconsideration of the lexical-postlexical dichotomy. Implication for modular versus interactive models of lexical access are discussed.

Adult↗