Two meta-analyses of 66 behavioral studies examined variables influencing functional cerebral lateralization of each language of brain-intact bilingual adults. Functional lateralization was found to be primarily influenced by age of onset of bilingualism: bilinguals who acquired both languages by 6 years of age showed bilateral hemispheric involvement for both languages, whereas those who acquired their second language after age 6 showed left hemisphere dominance for both languages. Moreover, among late bilinguals, left hemisphere involvement was found to be greater for those less proficient in their second language, those whose second language was English, and for studies involving dichotic listening paradigms; early bilinguals instead showed bilateral involvement in every condition. Implications of the observed differences in lateralization between early and late bilinguals are explored for existing theories of bilingualism and for neurocognitive models of brain functional organization of language.

Confirmatory factor analysis (CFA) and structural equation modeling (SEM) were used to study the organization of executive functions in older adults. The four primary goals were to examine (a) whether executive functions were supported by one versus multiple underlying factors, (b) which underlying skill(s) predicted performance on complex executive function tasks, (c) whether performance on analogous verbal and nonverbal tasks was supported by separable underlying skills, and (d) how patterns of performance generally compared with those of young adults. A sample of 100 older adults completed 10 tasks, each designed to engage one of three control processes: mental set shifting (Shifting), information updating or monitoring (Updating), and inhibition of prepotent responses (Inhibition). CFA identified robust Shifting and Updating factors, but the Inhibition factor failed to emerge, and there was no evidence for verbal and nonverbal factors. SEM showed that Updating was the best predictor of performance on each of the complex tasks the authors assessed (the Tower of Hanoi and the Wisconsin Card Sort). Results are discussed in terms of insight for theories of cognitive aging and executive function.

Seymour Ginsburg, a pioneer of formal language theory and database theory, passed away on December 5 after a long battle with Alzheimer's disease.

A meta-analysis was conducted on studies that examined hemispheric functional asymmetry for language in brain-intact monolingual and bilingual adults. Data from 23 laterality studies that directly compared bilingual and monolingual speakers on the same language were analysed (n0/ 1234). Variables examined were language experience (monolingual, bilingual), experimental paradigm (dichotic listening, visual hemifield presentation, and dual task) and, among bilinguals, the influence of second language proficiency (proficient vs nonproficient) and onset of bilingualism (early, or before age 6; and late, or after age 6). Overall, monolinguals and late bilinguals showed reliable left hemisphere dominance, while early bilinguals showed reliable bilateral hemispheric involvement. Within bilinguals, there was no reliable effect of language proficiency when age of L2 acquisition was controlled. The findings indicate that early learning of one vs. two languages predicts divergent patterns of cerebral language lateralisation in adulthood.Whereas remarkable progress has been made towards understanding how language is organised in the brain, much of this knowledge has come from studies of single language users and thus does not speak to the situation characterising the majority of the world's language users, who are bilingual or multilingual. Studying the neural concomitants of multiple language experience is important for redressing this gap and, from a broader perspective, to further our understanding of the neurological basis for the capacity for language in its various manifestations.Existing research on brain lateralisation of language supports the view that the left hemisphere (LH) is dominant for language, particularly for grammatical aspects of language, but that the right hemisphere (RH) also supports language processing, including aspects involved in discourse

Initially, infants are capable of discriminating phonetic contrasts across the world’s languages. Starting between seven and ten months of age, they gradually lose this ability through a process of perceptual narrowing. Although traditionally investigated with isolated speech sounds, such narrowing occurs in a variety of perceptual domains (e.g., faces, visual speech). Thus far, tracking the developmental trajectory of this tuning process has been focused primarily on auditory speech alone, and generally using isolated sounds. But infants learn from speech produced by people talking to them, meaning they learn from a complex audiovisual signal. Here, we use near-infrared spectroscopy to measure blood concentration changes in the bilateral temporal cortices of infants in three different age groups: 3-to-6 months, 7-to-10 months, and 11-to-14-months. Critically, all three groups of infants were tested with continuous audiovisual speech in both their native and another, unfamiliar language. We found that at each age range, infants showed different patterns of cortical activity in response to the native and non-native stimuli. Infants in the youngest group showed bilateral cortical activity that was greater overall in response to non-native relative to native speech; the oldest group showed left lateralized activity in response to native relative to non-native speech. These results highlight perceptual tuning as a dynamic process that happens across modalities and at different levels of stimulus complexity.