Relationships between neural activation during a reward task and peripheral cytokine levels in youth with diverse psychiatric symptoms.

Background: Inflammation has been hypothesized to contribute to reward dysfunction across psychiatric conditions, but little is known about this relationship in youth. Therefore, the present study investigated the associations between general and specific markers of inflammation and neural activation during reward processing, including anticipation and attainment, in youth with diverse psychiatric symptoms.

Methods: Forty-six psychotropic medication-free youth with diverse psychiatric symptoms underwent a blood draw to measure 41 cytokines, as well as structural and functional magnetic resonance imaging.

Elevated striatal γ-aminobutyric acid in youth with major depressive disorder.

Background: Alterations in γ-aminobutyric acid (GABA) have been hypothesized to play a role in the pathogenesis of psychiatric illness. Our previous work has specifically linked anterior cingulate cortex (ACC) GABA deficits with anhedonia in youth with major depressive disorder (MDD). As anhedonia reflects alterations within the reward circuitry, we sought to extend this investigation and examine GABA levels in another key reward-related region, the striatum, in the same adolescent population.

A pilot resting-state functional connectivity study of the kynurenine pathway in adolescents with depression and healthy controls.

Background: The neuroimmunological kynurenine pathway (KP) has been hypothesized to play a role in depressive/anhedonic symptoms and related CNS disturbances. Indoleamine 2,3-dioxygenase (IDO) is the rate limiting enzyme which leads to neurotrophic [kynurenic acid (KA)] and neurotoxic [Quinolinic acid (QUIN)] branches. In this pilot, we sought to examine associations between blood KP neuro-toxic/trophic measures and anhedonia/depression associated networks in youth with major depression (MDD) and healthy controls (HC).

Bilingual Cortical Control of Between- and Within-Language Competition.

The human capacity to master multiple languages is remarkable and leads to structural and functional changes in the brain. Understanding how the brain accommodates multiple languages simultaneously is crucial to developing a complete picture of our species' linguistic capabilities. To examine the neural mechanisms involved in processing two languages, we looked at cortical activation in Spanish-English bilinguals in response to phonological competition either between two languages or within a language.

Neural correlates of RDoC reward constructs in adolescents with diverse psychiatric symptoms: A Reward Flanker Task pilot study.

Background: There has been growing interest under the Research Domain Criteria initiative to investigate behavioral constructs and their underlying neural circuitry. Abnormalities in reward processes are salient across psychiatric conditions and may precede future psychopathology in youth. However, the neural circuitry underlying such deficits has not been well defined.

Neural signatures of second language learning and control.

Experience with multiple languages has unique effects on cortical structure and information processing. Differences in gray matter density and patterns of cortical activation are observed in lifelong bilinguals compared to monolinguals as a result of their experience managing interference across languages. Monolinguals who acquire a second language later in life begin to encounter the same type of linguistic interference as bilinguals, but with a different pre-existing language architecture.

Neural correlates of self-perceptions in adolescents with major depressive disorder.

Alteration in self-perception is a salient feature in major depression. Hyperactivity of anterior cortical midline regions has been implicated in this phenomenon in depressed adults. Here, we extend this work to depressed adolescents during a developmental time when neuronal circuitry underlying the sense of self matures by using task-based functional magnetic resonance imaging (fMRI) and connectivity analyses.

Plasticity of Interhemispheric Temporal Lobe White Matter Pathways Due to Early Disruption of Corpus Callosum Development in Spina Bifida.

Spina bifida myelomeningocele (SBM) is commonly associated with anomalous development of the corpus callosum (CC) because of congenital partial hypogenesis and hydrocephalus-related hypoplasia. It represents a model disorder to examine the effects of early disruption of CC neurodevelopment and the plasticity of interhemispheric white matter connections. Diffusion tensor imaging was acquired on 76 individuals with SBM and 27 typically developing individuals, aged 8-36 years.

Neural correlates of single word reading in bilingual children and adults.

The present study compared the neural correlates of language processing in children and adult Spanish-English bilinguals. Participants were asked to perform a visual lexical processing task in both Spanish and English while being scanned with fMRI. Both children and adults recruited a similar network of left hemisphere "language" areas and showed similar proficiency profiles in Spanish.

Differential recruitment of executive control regions during phonological competition in monolinguals and bilinguals.

Behavioral research suggests that monolinguals and bilinguals differ in how they manage within-language phonological competition when listening to language. The current study explored whether bilingual experience might also change the neural resources recruited to control spoken-word competition. Seventeen Spanish-English bilinguals and eighteen English monolinguals completed an fMRI task in which they searched for a picture representing an aurally presented word (e.

The influence of semantic property and grammatical class on semantic selection.

Research to-date has not successfully demonstrated consistent neural distinctions for different types of ambiguity or explored the effect of grammatical class on semantic selection. We conducted a relatedness judgment task using event-related functional magnetic resonance imaging (fMRI) to further explore these topics. Participants judged relatedness within word pairs.

Language experience differentiates prefrontal and subcortical activation of the cognitive control network in novel word learning.

The purpose of this study was to examine the cognitive control mechanisms in adult English speaking monolinguals compared to early sequential Spanish-English bilinguals during the initial stages of novel word learning. Functional magnetic resonance imaging during a lexico-semantic task after only 2h of exposure to novel German vocabulary flashcards showed that monolinguals activated a broader set of cortical control regions associated with higher-level cognitive processes, including the supplementary motor area (SMA), anterior cingulate (ACC), and dorsolateral prefrontal cortex (DLPFC), as well as the caudate, implicated in cognitive control of language. However, bilinguals recruited a more localized subcortical network that included the putamen, associated more with motor control of language.