Towards a model of language neurobiology in early development

Language processing following childhood poverty: Evidence for disrupted neural networks

Childhood poverty is related to deficits in multiple cognitive domains including adult language function. It is unknown if the brain basis of language is disrupted in adults with childhood poverty backgrounds, controlling for current functioning. Fifty-one adults (age 24) from an existing longitudinal study of childhood poverty, beginning at age 9, were examined on behavioral phonological awareness (LP) and completed an event-related fMRI speech/print processing LP task. Adults from childhood poverty backgrounds exhibited lower LP in adulthood. The middle-income group exhibited greater activation of the bilateral IFG and hippocampus during language processing. In psychophysiological interaction (PPI) analyses, the childhood poverty group exhibited greater coupling between ventral Broca's and the middle temporal gyrus (MTG) as well as coupling between Wernicke's region and bilateralization. Childhood poverty disrupts language processing neural networks in adulthood, after controlling for LP, suggesting that poverty in childhood influences the neurophysiological basis for language processing into adulthood.

Physical punishment and effective verbal communication in children aged 9-36 months, according to sex: secondary analysis of a national survey

BACKGROUND

A substantial number of children in the world are regularly subjected to physical punishment by their parents as a method of upbringing. Evidence suggests that it has negative effects on the development of brain function. However, evidence regarding its association with verbal communication is limited and heterogeneous. It is also unknown whether the effects are the same in both boys and girls; especially in the contexts of developing countries, where the highest rates of physical punishment are found.

OBJECTIVE

This investigation aimed at analyzing the association between physical punishment administered by both fathers and mothers and effective verbal communication among children aged 9-36 months according to sex.

METHODS

A secondary analytical cross-sectional study was conducted based on the 2018-2019 Peruvian Demographic and Family Health Survey. Physical punishment, based on the mother's report of the use of hitting and/or slapping, was considered as a method to correct children by the father and/or mother. Effective verbal communication (EVC) was measured using the Battle scale which consists of age-appropriate questions included in the early childhood development module. A generalized linear model of the family and Log Poisson link option was used to identify the association between them, using the crude, general adjusted, and sex-stratified models.

RESULTS

Of all the children, 16.31% received physical punishment from their father and/or mother, wherein 16.65% were boys and 15.97% were girls. Moreover, 36.48% exhibited EVC, wherein 32.55% were boys and 40.50% were girls. Adjusting for socioeconomic level, witnessing violence, mother's marital status, age, occupation, education level, language, number of children, and moderate-to-severe depressive symptoms, it was found that boys who received physical punishment from their father and/or mother have a 31% lower probability of EVC (adjusted prevalence ratio (aPR) 0.69, 95% confidence interval (CI) 0.58-0.83, p < 0.001), whereas no association was found in girls who received physical punishment from their father and/or mother and EVC (aPR 0.93, 95% CI 0.81-1.06, p = 0.278).

CONCLUSIONS

An association was found between physical punishment administered by father and/or mother and reduced EVC among boys, whereas no such association was found among girls. It is possible that even though a significant impact has not been observed in girls during this early stage, they may experience consequences in later stages of life, further research is needed.

Social Brain Perspectives on the Social and Evolutionary Neuroscience of Human Language

Human language and social cognition are two key disciplines that have traditionally been studied as separate domains. Nonetheless, an emerging view suggests an alternative perspective. Drawing on the theoretical underpinnings of the social brain hypothesis (thesis of the evolution of brain size and intelligence), the social complexity hypothesis (thesis of the evolution of communication), and empirical research from comparative animal behavior, human social behavior, language acquisition in children, social cognitive neuroscience, and the cognitive neuroscience of language, it is argued that social cognition and language are two significantly interconnected capacities of the human species. Here, evidence in support of this view reviews (1) recent developmental studies on language learning in infants and young children, pointing to the important crucial benefits associated with social stimulation for youngsters, including the quality and quantity of incoming linguistic information, dyadic infant/child-to-parent non-verbal and verbal interactions, and other important social cues integral for facilitating language learning and social bonding; (2) studies of the adult human brain, suggesting a high degree of specialization for sociolinguistic information processing, memory retrieval, and comprehension, suggesting that the function of these neural areas may connect social cognition with language and social bonding; (3) developmental deficits in language and social cognition, including autism spectrum disorder (ASD), illustrating a unique developmental profile, further linking language, social cognition, and social bonding; and (4) neural biomarkers that may help to identify early developmental disorders of language and social cognition. In effect, the social brain and social complexity hypotheses may jointly help to describe how neurotypical children and adults acquire language, why autistic children and adults exhibit simultaneous deficits in language and social cognition, and why nonhuman primates and other organisms with significant computational capacities cannot learn language. But perhaps most critically, the following article argues that this and related research will allow scientists to generate a holistic profile and deeper understanding of the healthy adult social brain while developing more innovative and effective diagnoses, prognoses, and treatments for maladies and deficits also associated with the social brain.

Atypical brain lateralization for speech processing at the sublexical level in autistic children revealed by fNIRS

Autistic children often exhibit atypical brain lateralization of language processing, but it is unclear what aspects of language contribute to this phenomenon. This study employed functional near-infrared spectroscopy to measure hemispheric lateralization by estimating hemodynamic responses associated with processing linguistic and non-linguistic auditory stimuli. The study involved a group of autistic children (N = 20, mean age = 5.8 years) and a comparison group of nonautistic peers (N = 20, mean age = 6.5 years). The children were presented with stimuli with systematically decreasing linguistic relevance: naturalistic native speech, meaningless native speech with scrambled word order, nonnative speech, and music. The results revealed that both groups showed left lateralization in the temporal lobe when listening to naturalistic native speech. However, the distinction emerged between autism and nonautistic in terms of processing the linguistic hierarchy. Specifically, the nonautistic comparison group demonstrated a systematic reduction in left lateralization as linguistic relevance decreased. In contrast, the autism group displayed no such pattern and showed no lateralization when listening to scrambled native speech accompanied by enhanced response in the right hemisphere. These results provide evidence of atypical neural specialization for spoken language in preschool- and school-age autistic children and shed new light on the underlying linguistic correlates contributing to such atypicality at the sublexical level.

The Musical Abilities, Pleiotropy, Language, and Environment (MAPLE) Framework for Understanding Musicality-Language Links Across the Lifespan

Using individual differences approaches, a growing body of literature finds positive associations between musicality and language-related abilities, complementing prior findings of links between musical training and language skills. Despite these associations, musicality has been often overlooked in mainstream models of individual differences in language acquisition and development. To better understand the biological basis of these individual differences, we propose the Musical Abilities, Pleiotropy, Language, and Environment (MAPLE) framework. This novel integrative framework posits that musical and language-related abilities likely share some common genetic architecture (i.e., genetic pleiotropy) in addition to some degree of overlapping neural endophenotypes, and genetic influences on musically and linguistically enriched environments. Drawing upon recent advances in genomic methodologies for unraveling pleiotropy, we outline testable predictions for future research on language development and how its underlying neurobiological substrates may be supported by genetic pleiotropy with musicality. In support of the MAPLE framework, we review and discuss findings from over seventy behavioral and neural studies, highlighting that musicality is robustly associated with individual differences in a range of speech-language skills required for communication and development. These include speech perception-in-noise, prosodic perception, morphosyntactic skills, phonological skills, reading skills, and aspects of second/foreign language learning. Overall, the current work provides a clear agenda and framework for studying musicality-language links using individual differences approaches, with an emphasis on leveraging advances in the genomics of complex musicality and language traits.

Predictive brain signals mediate association between shared reading and expressive vocabulary in infants

The ability to predict upcoming information is crucial for efficient language processing and enables more rapid language learning. The present study explored how shared reading experience influenced predictive brain signals and expressive vocabulary of 12-month-old infants. The predictive brain signals were measured by fNIRS responses in the occipital lobe with an unexpected visual-omission task. The amount of shared reading experience was correlated with the strength of this predictive brain signal and with infants’ expressive vocabulary. Importantly, the predictive brain signal explained unique variance of expressive vocabulary beyond shared reading experience and maternal education. A further mediation analysis showed that the effect of shared reading experience on expressive vocabulary was explained by the infants’ predictive brain signal. This is the first evidence indicating that richer shared reading experience strengthens predictive signals in the infant brain and in turn facilitates expressive vocabulary acquisition.

Top-down sensory prediction in the infant brain at 6 months is correlated with language development at 12 and 18 months

Previous research has suggested that top-down sensory prediction facilitates, and may be necessary for, efficient transmission of information in the brain. Here we related infants' vocabulary development to the top-down sensory prediction indexed by occipital cortex activation to the unexpected absence of a visual stimulus previously paired with an auditory stimulus. The magnitude of the neural response to the unexpected omission of a visual stimulus was assessed at the age of 6 months with functional near-infrared spectroscopy (fNIRS) and vocabulary scores were obtained using the MacArthur-Bates Communicative Development Inventory (MCDI) when infants reached the age of 12 months and 18 months, respectively. Results indicated significant positive correlations between this predictive neural signal at 6 months and MCDI expressive vocabulary scores at 12 and 18 months. These findings provide additional and robust support for the hypothesis that top-down prediction at the neural level plays a key role in infants' language development.

Common Neural Functions during Children's Learning from Naturalistic and Controlled Mathematics Paradigms

Two major goals of human neuroscience are to understand how the brain functions in the real world and to measure neural processes under conditions that are ecologically valid. A critical step toward these goals is understanding how brain activity during naturalistic tasks that mimic the real world relates to brain activity in more traditional laboratory tasks. In this study, we used intersubject correlations to locate reliable stimulus-driven cerebral processes among children and adults in a naturalistic video lesson and a laboratory forced-choice task that shared the same arithmetic concept. We show that relative to a control condition with grammatical content, naturalistic and laboratory arithmetic tasks evoked overlapping activation within brain regions previously associated with math semantics. The regions of specific functional overlap between the naturalistic mathematics lesson and laboratory mathematics task included bilateral intraparietal cortex, which confirms that this region processes mathematical content independently of differences in task mode. These findings suggest that regions of the intraparietal cortex process mathematical content when children are learning about mathematics in a naturalistic setting.