Searching for the principles of brain plasticity and behavior

The mediation effect of the inferior-parietal cortex and globus pallidus on the relationship between family conflict and major depressive disorder

OBJECTIVE

Family conflict is an important risk factor for major depressive disorder (MDD) and is associated with structural alterations in the brain. However, it is unclear whether structural alterations associated with family conflict would contribute to depression. This study aims to investigate the neuroimaging characteristics that connect family conflict with depression.

METHODS

This study included 54 healthy controls and 53 antidepressant-free patients with MDD. Both groups completed the Beck Depression Inventory-II, the simplified Chinese version of the Family Environment Scale, and the Childhood Trauma Questionnaire. Structural Magnetic Resonance Imaging data was collected to measure cortical thickness and regional gray matter volumes.

RESULTS

Family conflict has a significant effect on depression diagnosis. Higher levels of family conflict were positively associated with symptoms of sadness, guilty feelings, and punishment feelings in patients, as well as with cortical thickness in the right inferior-parietal cluster and the volumes of the left globus pallidus in all participants. In the patient group, cortical thickness in the right inferior-parietal cluster and volume of the left globus pallidus were negatively related to symptoms of sadness and guilty feelings, respectively. The structural alteration in the right inferior-parietal cluster mediated the relationship of family conflict and sadness, whereas changes in the globus pallidus mediated the associations between family conflict and both depression and guilty feelings in patients.

CONCLUSION

Findings revealed the relationships between family conflict and depression, including both depression diagnosis and specific symptoms. Cortical thickness in the right inferior-parietal cortex and the volume of the left globus pallidus played mediating roles in these relationships, indicating the important contributions of these brain regions to the effect of family conflict on depression.

Strengthening through adversity: The hormesis model in developmental psychopathology

BACKGROUND

Employing a developmental psychopathology framework, we tested the utility of the hormesis model in examining the strengthening of children and youth through limited levels of adversity in relation to internalizing and externalizing outcomes within a brain-by-development context.

METHODS

Analyzing data from the Adolescent Brain and Cognitive Development study (N = 11,878), we formed latent factors of threat, deprivation, and unpredictability. We examined linear and nonlinear associations between adversity dimensions and youth psychopathology symptoms and how change of resting-state functional connectivity (rsFC) in the default mode network (DMN) from Time 1 to Time 5 moderates these associations.

RESULTS

A cubic association was found between threat and youth internalizing problems; low-to-moderate family conflict levels reduced these problems. Deprivation also displayed a cubic relation with youth externalizing problems, with moderate deprivation levels associated with fewer problems. Unpredictability linearly increased both problem types. Change in DMN rsFC significantly moderated the cubic link between threat levels and internalizing problems, with declining DMN rsFC levels from Time 1 to Time 5 facilitating hormesis. Hormetic effects peaked earlier, emphasizing the importance of sensitive periods and developmental timing of outcomes related to earlier experiences.

CONCLUSIONS

Strengthening through limited environmental adversity is crucial for developing human resilience. Understanding this process requires considering both linear and nonlinear adversity-psychopathology associations. Testing individual differences by brain and developmental context will inform preventive intervention programming.

Early-life threat and deprivation: Are children similarly affected by exposure to each?

Extensive evidence documents negative consequences of adversity for children's development. Here, we extend such work by looking beyond average effects to consider variation in susceptibility to both threat and deprivation in terms of cognitive and social-emotional development, using an influence-statistic methodology. Data come from the ongoing Avon Longitudinal Study of Parents and Children (N = 14,541, 49.1% female, age range: 6 month to 12 year, race and ethnicity: 97.8% white, 0.4% black, and 0.6% other). With respect to anticipated associations of threat with problem behavior and of deprivation with cognition, results of this pre-registered research revealed that a roughly equal proportion of children proved to be susceptible in a domain-general manner (similarly influenced) and a domain-specific one (dissimilarly influenced). Implications for intervention are considered.

Rethinking plasticity: Analysing the concept of "destructive plasticity" in the light of neuroscience definitions

As a multilevel and multidisciplinary field, neuroscience is designed to interact with various branches of natural and applied sciences as well as with humanities and philosophy. The continental tradition in philosophy, particularly over the past 20 years, tended to establish strong connections with biology and neuroscience findings. This cross fertilization can however be impeded by conceptual intricacies, such as those surrounding the concept of plasticity. The use of this concept has broadened as scientists applied it to explore an ever-growing range of biological phenomena. Here, we examine the consequences of this ambiguity in an interdisciplinary context through the analysis of the concept of "destructive plasticity" in the philosophical writings of Catherine Malabou. The term "destructive plasticity" was coined by Malabou in 2009 to refer to all processes leading to psycho-cognitive and emotional alterations following traumatic or nontraumatic brain injuries or resulting from neurodevelopmental disorders. By comparing it with the neuroscientific definitions of plasticity, we discuss the epistemological obstacles and possibilities related to the integration of this concept into neuroscience. Improving interdisciplinary exchanges requires an advanced and sophisticated manipulation of neurobiological concepts. These concepts are not only intended to guide research programmes within neuroscience but also to organize and frame the dialogue between different theoretical backgrounds.

Traumatic childhood experiences and personality functioning: effect of body connection in a cross-sectional German and Chilean sample

BACKGROUND

Traumatic childhood experiences are a major risk factor for developing mental disorders later in life. Over the past decade, researchers have begun to investigate the role of early trauma in impairments in personality functioning following the introduction of the Alternative Model of Personality Disorders in Section III of the Diagnostic and Statistical Manual for Mental Disorders 5. Although first studies were able to empirically demonstrate a significant link between early trauma and impairments in personality functioning, only little is known about the underlying mechanisms. One possible mechanism is body connection due to its involvement in self-regulatory processes and its link to both early trauma and personality (dys)functioning.

OBJECTIVE

In the current study, we investigated whether body connection, which encompasses the awareness, integration, and utilization of one's own bodily signals, mediates the relationship between childhood trauma and personality functioning.

PARTICIPANTS AND SETTING

A total of 1,313 adult participants recruited in Germany and Chile anonymously provided self-report data in an online survey.

METHODS

Self-report data included the short form of the Childhood Trauma Questionnaire (CTQ-SF), the Scale of Body Connection (SBC), and the brief form of the Levels of Personality Functioning Scale (LPFS-BF 2.0) as well as demographic data (age, sex, education, clinical diagnoses).

RESULTS

Traumatic childhood experiences explained 27.2% of the variance in impairments in personality functioning. Interestingly, 60.5% of this effect was explained by body connection, particularly body dissociation. Additional exploratory analyses revealed that body dissociation and, to a much lesser extent, body awareness, accounted for 64.41% of the variance in self functioning and 55.75% of the variance in interpersonal functioning explained by childhood trauma.

CONCLUSION

Body connection appears to be an important mediator in the association between early trauma and impaired personality functioning, underscoring the need for interventions specifically targeting the avoidance and ignorance of signals from one's own body in individuals with traumatic childhood trauma.

Real-time auditory feedback for improving gait and walking in people with Parkinson's disease: a pilot and feasibility trial

BACKGROUND

Technology is poised to bridge the gap between demand for therapies to improve gait in people with Parkinson's and available resources. A wearable sensor, Heel2Toe™, a small device that attaches to the side of the shoe and gives a sound each time the person starts their step with a strong heel strike, has been developed and pre-tested by a team at McGill University. The objective of this study was to estimate feasibility and efficacy potential of the Heel2Toe™ sensor in changing walking capacity and gait pattern in people with Parkinson's.

METHODS

A pilot study was carried out involving 27 people with Parkinson's randomized 2:1 to train with the Heel2Toe[TM] sensor and or to train with recommendations from a gait-related workbook.

RESULTS

A total of 21 completed the 3-month evaluation, 14 trained with the Heel2Toe[TM] sensor, and 7 trained with the workbook. Thirteen of 14 people in the Heel2Toe group improved over measurement error on the primary outcome, the 6-Minute Walk Test, (mean change 66.4 m) and 0 of the 7 in the Workbook group (mean change - 19.4 m): 4 of 14 in the Heel2Toe group made reliable change and 0 of 7 in the Workbook group. Improvements in walking distance were accompanied by improvements in gait quality. Forty percent of participants in the intervention group were strongly satisfied with their technology experience and an additional 37% were satisfied.

CONCLUSIONS

Despite some technological difficulties, feasibility and efficacy potential of the Heel2Toe sensor in improving gait in people with Parkinson's was supported.

Mapping the unique neural engagement in deaf individuals during picture, word, and sign language processing: fMRI study

Employing functional magnetic resonance imaging (fMRI) techniques, we conducted a comprehensive analysis of neural responses during sign language, picture, and word processing tasks in a cohort of 35 deaf participants and contrasted these responses with those of 35 hearing counterparts. Our voxel-based analysis unveiled distinct patterns of brain activation during language processing tasks. Deaf individuals exhibited robust bilateral activation in the superior temporal regions during sign language processing, signifying the profound neural adaptations associated with sign comprehension. Similarly, during picture processing, the deaf cohort displayed activation in the right angular, right calcarine, right middle temporal, and left angular gyrus regions, elucidating the neural dynamics engaged in visual processing tasks. Intriguingly, during word processing, the deaf group engaged the right insula and right fusiform gyrus, suggesting compensatory mechanisms at play during linguistic tasks. Notably, the control group failed to manifest additional or distinctive regions in any of the tasks when compared to the deaf cohort, underscoring the unique neural signatures within the deaf population. Multivariate Pattern Analysis (MVPA) of functional connectivity provided a more nuanced perspective on connectivity patterns across tasks. Deaf participants exhibited significant activation in a myriad of brain regions, including bilateral planum temporale (PT), postcentral gyrus, insula, and inferior frontal regions, among others. These findings underscore the intricate neural adaptations in response to auditory deprivation. Seed-based connectivity analysis, utilizing the PT as a seed region, revealed unique connectivity pattern across tasks. These connectivity dynamics provide valuable insights into the neural interplay associated with cross-modal plasticity.

How adverse childhood experiences get under the skin: A systematic review, integration and methodological discussion on threat and reward learning mechanisms

Adverse childhood experiences (ACEs) are a major risk factor for the development of multiple psychopathological conditions, but the mechanisms underlying this link are poorly understood. Associative learning encompasses key mechanisms through which individuals learn to link important environmental inputs to emotional and behavioral responses. ACEs may impact the normative maturation of associative learning processes, resulting in their enduring maladaptive expression manifesting in psychopathology. In this review, we lay out a systematic and methodological overview and integration of the available evidence of the proposed association between ACEs and threat and reward learning processes. We summarize results from a systematic literature search (following PRISMA guidelines) which yielded a total of 81 articles (threat: n=38, reward: n=43). Across the threat and reward learning fields, behaviorally, we observed a converging pattern of aberrant learning in individuals with a history of ACEs, independent of other sample characteristics, specific ACE types, and outcome measures. Specifically, blunted threat learning was reflected in reduced discrimination between threat and safety cues, primarily driven by diminished responding to conditioned threat cues. Furthermore, attenuated reward learning manifested in reduced accuracy and learning rate in tasks involving acquisition of reward contingencies. Importantly, this pattern emerged despite substantial heterogeneity in ACE assessment and operationalization across both fields. We conclude that blunted threat and reward learning may represent a mechanistic route by which ACEs may become physiologically and neurobiologically embedded and ultimately confer greater risk for psychopathology. In closing, we discuss potentially fruitful future directions for the research field, including methodological and ACE assessment considerations.

The Effect of Long-Term Learning of BaduanJin on Emotion Regulation: Evidence from Resting-State Frontal EEG Asymmetry

Purpose

Baduanjin, as a Chinese traditional fitness exercise, can help people regulate emotions and promote their physical and psychological health. However, the underlying neural mechanisms have not been thoroughly explored. This study aimed to examine the effects of differences in the level of Baduanjin learning on individuals' brain and psychological response related to emotion regulation.

Methods

Twenty-two participants with long-term Baduanjin learning (for more than one year), and 21 participants with short-term Baduanjin learning (for approximately three months) were recruited. All participants were asked to do a complete 12-minute set of Baduanjin. Before and after doing Baduanjin, their resting-state EEG signals were collected, besides, the Emotion Regulation Questionnaire (ERQ) and the Profile of Mood States-Short Form (POMS-SF) were used to assess participants' emotion regulation strategies and abilities.

Results

The results of psychological measurement indicated that participants in the long-term group were more likely to use cognitive reappraisal as an emotion regulation strategy compared to participants in the short-term group (p<0.05). Moreover, the analysis of the frontal alpha asymmetry (FAA) showed that participants in the long-term group rather than the short-term group exhibited significant left lateralization after doing Baduanjin (p<0.05).

Conclusion

The findings provide preliminary evidence for the neural mechanism underlying how long-term Baduanjin learning promotes individuals' emotion regulation indexed by FAA. The study provides a new paradigm for research on how Baduanjin affects emotional regulation.

Randomized controlled trials of non-pharmacological interventions for healthy seniors: Effects on cognitive decline, brain plasticity and activities of daily living-A 23-year scoping review

Little is known about the simultaneous effects of non-pharmacological interventions (NPI) on healthy older adults' behavior and brain plasticity, as measured by psychometric instruments and magnetic resonance imaging (MRI). The purpose of this scoping review was to compile an extensive list of randomized controlled trials published from January 1, 2000, to August 31, 2023, of NPI for mitigating and countervailing age-related physical and cognitive decline and associated cerebral degeneration in healthy elderly populations with a mean age of 55 and over. After inventorying the NPI that met our criteria, we divided them into six classes: single-domain cognitive, multi-domain cognitive, physical aerobic, physical non-aerobic, combined cognitive and physical aerobic, and combined cognitive and physical non-aerobic. The ultimate purpose of these NPI was to enhance individual autonomy and well-being by bolstering functional capacity that might transfer to activities of daily living. The insights from this study can be a starting point for new research and inform social, public health, and economic policies. The PRISMA extension for scoping reviews (PRISMA-ScR) checklist served as the framework for this scoping review, which includes 70 studies. Results indicate that medium- and long-term interventions combining non-aerobic physical exercise and multi-domain cognitive interventions best stimulate neuroplasticity and protect against age-related decline and that outcomes may transfer to activities of daily living.

The impacts of early environmental adversity on cognitive functioning, body mass, and life-history behavioral profiles

Early adverse experiences or exposures have a profound impact on neurophysiological, cognitive, and somatic development. Evidence across disciplines uncovers adversity-induced alternations in cortical structures, cognitive functions, and related behavioral manifestations, as well as an energetic trade-off between the brain and body. Based on the life history (LH) framework, the present research aims to explore the adversity-adapted cognitive-behavioral mechanism and investigate the relation between cognitive functioning and somatic energy reserve (i.e., body mass index; BMI). A structural equation modeling (SEM) analysis was performed with longitudinal self-reported, anthropometric, and task-based data drawn from a cohort of 2,607 8- to 11-year-old youths and their primary caregivers recruited by the Adolescent Brain Cognitive Development (ABCDSM) study. The results showed that early environmental adversity was positively associated with fast LH behavioral profiles and negatively with cognitive functioning. Moreover, cognitive functioning mediated the relationship between adversity and fast LH behavioral profiles. Additionally, we found that early environmental adversity positively predicted BMI, which was inversely correlated with cognitive functioning. These results revealed an adversity-adapted cognitive-behavioral mechanism and energy-allocation pathways, and add to the existing knowledge of LH trade-off and developmental plasticity.

Global topology of human connectome is insensitive to early life environments - A prospective longitudinal study of the general population

The widely acknowledged detrimental impact of early adversity on child development has driven efforts to understand the underlying mechanisms that may mediate these effects within the developing brain. Recent efforts have begun to move beyond associating adversity with the morphology of individual brain regions towards determining if and how adversity might shape their interconnectivity. However, whether adversity effects a global shift in the organisation of whole-brain networks remains unclear. In this study, we assessed this possibility using parental questionnaire and diffusion imaging data from The Avon Longitudinal Study of Parents and Children (ALSPAC, N = 913), a prospective longitudinal study spanning more than 20 years. We tested whether a wide range of adversities-including experiences of abuse, domestic violence, physical and emotional cruelty, poverty, neglect, and parental separation-measured by questionnaire within the first seven years of life were significantly associated with the tractography-derived connectome in young adulthood. We tested this across multiple measures of organisation and using a computational model that simulated the wiring economy of the brain. We found no significant relationships between early exposure to any form of adversity and the global organisation of the structural connectome in young adulthood. We did detect local differences in the medial prefrontal cortex, as well as an association between weaker brain wiring constraints and greater externalising behaviour in adolescence. Our results indicate that further efforts are necessary to delimit the magnitude and functional implications of adversity-related differences in connectomic organization. RESEARCH HIGHLIGHTS: Diverse prospective measures of the early-life environment do not predict the organisation of the DTI tractography-derived connectome in young adulthood Wiring economy of the connectome is weakly associated with externalising in adolescence, but not internalising or cognitive ability Further work is needed to establish the scope and significance of global adversity-related differences in the structural connectome.

Different cortical connectivities in human females and males relate to differences in strength and body composition, reward and emotional systems, and memory

Sex differences in human brain structure and function are important, partly because they are likely to be relevant to the male-female differences in behavior and in mental health. To analyse sex differences in cortical function, functional connectivity was measured in 36,531 participants (53% female) in the UK Biobank (mean age 69) using the Human Connectome Project multimodal parcellation atlas with 360 well-specified cortical regions. Most of the functional connectivities were lower in females (Bonferroni corrected), with the mean Cohen's d =  - 0.18. Removing these as covariates reduced the difference of functional connectivities for females-males from d =  - 0.18 to - 0.06. The lower functional connectivities in females were especially of somatosensory/premotor regions including the insula, opercular cortex, paracentral lobule and mid-cingulate cortex, and were correlated with lower maximum workload (r = 0.17), and with higher whole body fat mass (r =  - 0.17). But some functional connectivities were higher in females, involving especially the ventromedial prefrontal cortex and posterior cingulate cortex, and these were correlated with higher liking for some rewards such as sweet foods, higher happiness/subjective well-being, and with better memory-related functions. The main findings were replicated in 1000 individuals (532 females, mean age 29) from the Human Connectome Project. This investigation shows the cortical systems with different functional connectivity between females and males, and also provides for the first time a foundation for understanding the implications for behavior of these differences between females and males.

Upper limb modeling and motion extraction based on multi-space-fusion

Modeling and motion extraction of human upper limbs are essential for interpreting the natural behavior of upper limb. Owing to the high degrees of freedom (DOF) and highly dynamic nature, existing upper limb modeling methods have limited applications. This study proposes a generic modeling and motion extraction method, named Primitive-Based triangular body segment method (P-BTBS), which follows the physiology of upper limbs, allows high accuracy of motion angles, and describes upper-limb motions with high accuracy. For utilizing the upper-limb modular motion model, the motion angles and bones can be selected as per the research topics (The generic nature of the study targets). Additionally, P-BTBS is suitable in most scenarios for estimating spatial coordinates (The generic nature of equipment and technology). Experiments in continuous motions with seven DOFs and upper-limb motion description validated the excellent performance and robustness of P-BTBS in extracting motion information and describing upper-limb motions, respectively. P-BTBS provides a new perspective and mathematical tool for human understanding and exploration of upper-limb motions, which theoretically supports upper-limb research.

Enhancing Child Development in Oman: Applying global agenda into local context

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Reorganization in the macaque interoceptive-allostatic network following anterior cingulate cortex damage

Accumulating evidence indicates that the adult brain is capable of significant structural change following damage-a capacity once thought to be largely limited to developing brains. To date, most existing research on adult plasticity has focused on how exteroceptive sensorimotor networks compensate for damage to preserve function. Interoceptive networks-those that represent and process sensory information about the body's internal state-are now recognized to be critical for a wide range of physiological and psychological functions from basic energy regulation to maintaining a sense of self, but the extent to which these networks remain plastic in adulthood has not been established. In this report, we used detailed histological analyses to pinpoint precise changes to gray matter volume in the interoceptive-allostatic network in adult rhesus monkeys (Macaca mulatta) who received neurotoxic lesions of the anterior cingulate cortex (ACC) and neurologically intact control monkeys. Relative to controls, monkeys with ACC lesions had significant and selective unilateral expansion of the ventral anterior insula and significant relative bilateral expansion of the lateral nucleus of the amygdala. This work demonstrates the capacity for neuroplasticity in the interoceptive-allostatic network which, given that changes included expansion rather than atrophy, is likely to represent an adaptive response following damage.

A Guide for the Multiplexed: The Development of Visual Feature Maps in the Brain

Neural maps are found ubiquitously in the brain, where they encode a wide range of behaviourally relevant features into neural space. Developmental studies have shown that animals devote a great deal of resources to establish consistently patterned organization in neural circuits throughout the nervous system, but what purposes maps serve beneath their often intricate appearance and composition is a topic of active debate and exploration. In this article, we review the general mechanisms of map formation, with a focus on the visual system, and then survey notable organizational properties of neural maps: the multiplexing of feature representations through a nested architecture, the interspersing of fine-scale heterogeneity within a globally smooth organization, and the complex integration at the microcircuit level that enables a high dimensionality of information encoding. Finally, we discuss the roles of maps in cortical functions, including input segregation, feature extraction and routing of circuit outputs for higher order processing, as well as the evolutionary basis for the properties we observe in neural maps.

Learnings in developmental and epileptic encephalopathies: what do we know?

INTRODUCTION

Developmental and Epileptic Encephalopathies (DEEs) encompass a group of neurological disorders caused by either abnormal neuronal development and white matter maturation or even by weak synaptic plasticity. Hitherto, patients commonly have epileptic seizures featuring cognitive dysfunction, such as neurosensory disorders, difficulties in learning, behavioral disturbances, or speech delay.

AREAS COVERED

This paper provides a comprehensive review of the current knowledge of DEEs and cognition. Medline/Pubmed database was screened for in-English articles published between 1967-2022 dealing with the topic of DEEs and cognitive development. Two authors independently screened the title and abstract of each record and reviewed the selected articles. Reviews, randomized clinical trials, and case reports were selected.

EXPERT OPINION

Scientific literature has never explicitly dealt with the early neuro-psychomotor rehabilitation and neuropsychological assessment of patients with DEEs. Targeted intervention and environmental stimuli can influence the maturation of neuronal circuits and shape changes in physical and mental development based on neuronal plasticity, particularly if applied in 'critical periods' liable to heightened sensitivity. Thus, 'early neurorehabilitation interventions' are worthy of being more and more applied to clinical practice to improve the quality of life and reduce the psychosocial burden on families and caregivers.

What microglia depletion approaches tell us about the role of microglia on synaptic function and behavior

Microglia are dynamic cells, constantly surveying their surroundings and interacting with neurons and synapses. Indeed, a wealth of knowledge has revealed a critical role of microglia in modulating synaptic transmission and plasticity in the developing brain. In the past decade, novel pharmacological and genetic strategies have allowed the acute removal of microglia, opening the possibility to explore and understand the role of microglia also in the adult brain. In this review, we summarized and discussed the contribution of microglia depletion strategies to the current understanding of the role of microglia on synaptic function, learning and memory, and behavior both in physiological and pathological conditions. We first described the available microglia depletion methods highlighting their main strengths and weaknesses. We then reviewed the impact of microglia depletion on structural and functional synaptic plasticity. Next, we focused our analysis on the effects of microglia depletion on behavior, including general locomotor activity, sensory perception, motor function, sociability, learning and memory both in healthy animals and animal models of disease. Finally, we integrated the findings from the reviewed studies and discussed the emerging roles of microglia on the maintenance of synaptic function, learning, memory strength and forgetfulness, and the implications of microglia depletion in models of brain disease.

Neuronal RNA granules are ribosome complexes stalled at the pre-translocation state

The polarized cell morphology of neurons dictates many neuronal processes, including the axodendridic transport of specific mRNAs and subsequent translation. mRNAs together with ribosomes and RNA-binding proteins form RNA granules that are targeted to axodendrites for localized translation in neurons. It has been established that localized protein synthesis in neurons is essential for long-term memory formation, synaptic plasticity, and neurodegeneration. We have used proteomics and electron microscopy to characterize neuronal RNA granules (nRNAg) isolated from rat brain tissues or human neuroblastoma. We show that ribosome containing RNA granules are morula-like structures when visualized by electron microscopy. Crosslinking-coupled mass-spectrometry identified potential G3BP2 binding site on the ribosome near the eIF3d-binding site on the 40S ribosomal subunit. We used cryo-EM to resolve the structure of the ribosome-component of nRNAg. The cryo-EM reveals that predominant particles in nRNAg are 80S ribosomes, resembling the pre-translocation state where tRNA's are in the hybrid A/P and P/E site. We also describe a new kind of principal motion of the ribosome, which we call the rocking motion.

Context-sensitive computational mechanistic explanation in cognitive neuroscience

Mainstream cognitive neuroscience aims to build mechanistic explanations of behavior by mapping abilities described at the organismal level via the subpersonal level of computation onto specific brain networks. We provide an integrative review of these commitments and their mismatch with empirical research findings. Context-dependent neural tuning, neural reuse, degeneracy, plasticity, functional recovery, and the neural correlates of enculturated skills each show that there is a lack of stable mappings between organismal, computational, and neural levels of analysis. We furthermore highlight recent research suggesting that task context at the organismal level determines the dynamic parcellation of functional components at the neural level. Such instability prevents the establishment of specific computational descriptions of neural function, which remains a central goal of many brain mappers - including those who are sympathetic to the notion of many-to-many mappings between organismal and neural levels. This between-level instability presents a deep epistemological challenge and requires a reorientation of methodological and theoretical commitments within cognitive neuroscience. We demonstrate the need for change to brain mapping efforts in the face of instability if cognitive neuroscience is to maintain its central goal of constructing computational mechanistic explanations of behavior; we show that such explanations must be contextual at all levels.

Environmental Conditions to Promote Healthy Childhood Brain/Behavioral Development: Informing Early Preventive Interventions for Delivery in Routine Care

Environmental experiences early in life have strong and enduring consequences for cognitive, emotional, and neurobiological development and related physical and mental health trajectories. The powerful influence of early caregiver nurturance and stimulation on promoting positive neurodevelopmental outcomes has been demonstrated across species. These findings elucidate the environmental conditions known to facilitate healthy neurodevelopment and underscore the potential for modifiable psychosocial factors in the environment to be harnessed to inform early preventive interventions to promote health and adaptive development. A framework for early preventive interventions to enhance nurturing and responsive caregiving for implementation during early sensitive periods of brain development delivered within existing health or educational infrastructures is proposed. Emotional development during sensitive periods is an important, under-recognized, and abundantly modifiable predictor of mental and physical health outcomes that warrants investment of resources and integration of interventions into public health infrastructure for children worldwide. Future studies are needed to further clarify whether and when sensitive periods are present for key developmental domains to inform the optimal timing and targets of these interventions. Numerous available empirically supported early interventions may be modified and applied in briefer and more feasible modalities of delivery to broader populations of developing children. As well established in growth and development across species, essential environmental inputs that are particularly important at specified developmental periods facilitate optimal growth trajectories. Such principles hold great potential in application to early child neurodevelopment to facilitate a thriving and resilient human population.

The effects of early life adversity on children's mental health and cognitive functioning

Emerging evidence suggests that partially distinct mechanisms may underlie the association between different dimensions of early life adversity (ELA) and psychopathology in children and adolescents. While there is minimal evidence that different types of ELA are associated with specific psychopathology outcomes, there are partially unique cognitive and socioemotional consequences of specific dimensions of ELA that increase transdiagnostic risk of mental health problems across the internalizing and externalizing spectra. The current review provides an overview of recent findings examining the cognitive (e.g., language, executive function), socioemotional (e.g., attention bias, emotion regulation), and mental health correlates of ELA along the dimensions of threat/harshness, deprivation, and unpredictability. We underscore similarities and differences in the mechanisms connecting different dimensions of ELA to particular mental health outcomes, and identify gaps and future directions that may help to clarify inconsistencies in the literature. This review focuses on childhood and adolescence, periods of exquisite neurobiological change and sensitivity to the environment. The utility of dimensional models of ELA in better understanding the mechanistic pathways towards the expression of psychopathology is discussed, with the review supporting the value of such models in better understanding the developmental sequelae associated with ELA. Integration of dimensional models of ELA with existing models focused on psychiatric classification and biobehavioral mechanisms may advance our understanding of the etiology, phenomenology, and treatment of mental health difficulties in children and youth.

Why and how does early adversity influence development? Toward an integrated model of dimensions of environmental experience

Two extant frameworks - the harshness-unpredictability model and the threat-deprivation model - attempt to explain which dimensions of adversity have distinct influences on development. These models address, respectively, why, based on a history of natural selection, development operates the way it does across a range of environmental contexts, and how the neural mechanisms that underlie plasticity and learning in response to environmental experiences influence brain development. Building on these frameworks, we advance an integrated model of dimensions of environmental experience, focusing on threat-based forms of harshness, deprivation-based forms of harshness, and environmental unpredictability. This integrated model makes clear that the why and the how of development are inextricable and, together, essential to understanding which dimensions of the environment matter. Core integrative concepts include the directedness of learning, multiple levels of developmental adaptation to the environment, and tradeoffs between adaptive and maladaptive developmental responses to adversity. The integrated model proposes that proximal and distal cues to threat-based and deprivation-based forms of harshness, as well as unpredictability in those cues, calibrate development to both immediate rearing environments and broader ecological contexts, current and future. We highlight actionable directions for research needed to investigate the integrated model and advance understanding of dimensions of environmental experience.

Using Robot-Based Variables during Upper Limb Robot-Assisted Training in Subacute Stroke Patients to Quantify Treatment Dose

In post-stroke motor rehabilitation, treatment dose description is estimated approximately. The aim of this retrospective study was to quantify the treatment dose using robot-measured variables during robot-assisted training in patients with subacute stroke. Thirty-six patients performed fifteen 60 min sessions (Session 1−Session 15) of planar, target-directed movements in addition to occupational therapy over 4 (SD 2) weeks. Fugl−Meyer Assessment (FMA) was carried out pre- and post-treatment. The actual time practiced (percentage of a 60 min session), the number of repeated movements, and the total distance traveled were analyzed across sessions for each training modality: assist as needed, unassisted, and against resistance. The FMA score improved post-treatment by 11 (10) points (Session 1 vs. Session 15, p < 0.001). In Session 6, all modalities pooled, the number of repeated movements increased by 129 (252) (vs. Session 1, p = 0.043), the total distance traveled increased by 1743 (3345) cm (vs. Session 1, p = 0.045), and the actual time practiced remained unchanged. In Session 15, the actual time practiced showed changes only in the assist-as-needed modality: −13 (23) % (vs. Session 1, p = 0.013). This description of changes in quantitative-practice-related variables when using different robotic training modalities provides comprehensive information related to the treatment dose in rehabilitation. The treatment dose intensity may be enhanced by increasing both the number of movements and the motor difficulty of performing each movement.

Long-Term Mental Health and Quality of Life Outcomes of Neonatal Insults in Kilifi, Kenya

We examined the mental health and quality of life (QoL) outcomes and their correlates of school-aged survivors of neonatal jaundice (NNJ), hypoxic-ischemic encephalopathy (HIE), and a comparison group. The Child Behavior Checklist and the Pediatric Quality of Life Inventory were administered to assess the mental health and QoL of 375 children (134 with NNJ, 107 with HIE, and 134 comparison group) aged 6 to 12 years [Median age 9 (interquartile range 7 to 11)]. The results showed that survivors of NNJ and HIE have mental health problems and QoL similar to the comparison group. Maternal mental health was the predominant covariate of mental health and QoL in survivors of NNJ and HIE. This result could indicate that mothers with mental health problems are more likely to have children with mental health issues, but also that caring for children with these adversities may affect mental health well-being of the caregivers. There is a need for early mental health screening and psychosocial intervention for caregivers and their children to enhance both their mental health and QoL.

Developmental diversity: Putting the development back into research about developmental conditions

The dominant discourse surrounding neurodevelopmental conditions such as autism and ADHD emphasizes biological explanations. Neurodevelopmental conditions are conceived as different types of brains, the result of different types of genes. This way of thinking is present both in medical research and in clinical practice. Indeed, it is widely acknowledged that the idea of having a biological diagnosis helps people see beyond blame and guilt. It aids acceptance. However, simplistic approaches to biology risks neglecting the experiences and stories of autistic people in favor of finding etiological causes. At the same time, there is growing awareness that risks, functioning, and resilience are not solely defined by genes and brains but have a cultural and experiential component as well. Furthermore, atypical cognitive trajectories are not straightforwardly associated with poor outcomes. In this paper we describe the concept of developmental diversity as an alternative to more categorical approaches to neurodevelopmental conditions. We explore how dynamic models of life offer possibilities to look at neurodevelopmental conditions differently: rather than seeing autistic people as people with fundamental flaws in their genes or software faults in their brains that have to be explained, autism appears as a phenomenon that exists in interaction with the context, as a meaningful reaction to the environment. We explore what it would mean for research to go from a diagnosis-based approach to a developmental diversity approach that will define wellbeing and functioning in a more granular way across developmental trajectories. We argue that this would mean incorporating lived experiences into biological research and going beyond genes-environment dichotomies. Next to yielding a more complete picture on the phenomenon of autism, we describe how an approach that takes developmental diversity as a starting point offers a new way to look at existing challenges of autism research, such as how to deal with the significant overlap between diagnosis. Our hypothesis is that thinking with developmental diversity rather than categorical difference both represents an opportunity for a more inclusive society, and fundamentally can alter the way we perform research. As such, it is in line with requests of neurodiversity and disability movements.

The Value of Dimensional Models of Early Experience: Thinking Clearly About Concepts and Categories

We review the three prevailing approaches-specificity, cumulative risk, and dimensional models-to conceptualizing the developmental consequences of early-life adversity and address fundamental problems with the characterization of these frameworks in a recent Perspectives on Psychological Science piece by Smith and Pollak. We respond to concerns raised by Smith and Pollak about dimensional models of early experience and highlight the value of these models for studying the developmental consequences of early-life adversity. Basic dimensions of adversity proposed in existing models include threat/harshness, deprivation, and unpredictability. These models identify core dimensions of early experience that cut across the categorical exposures that have been the focus of specificity and cumulative risk approaches (e.g., abuse, institutional rearing, chronic poverty); delineate aspects of early experience that are likely to influence brain and behavioral development; afford hypotheses about adaptive and maladaptive responses to different dimensions of adversity; and articulate specific mechanisms through which these dimensions exert their influences, conceptualizing experience-driven plasticity within an evolutionary-developmental framework. In doing so, dimensional models advance specific falsifiable hypotheses, grounded in neurodevelopmental and evolutionary principles, that are supported by accumulating evidence and provide fertile ground for empirical studies on early-life adversity.

Brain Functional Connectivity Changes in Patients with Acute Eye Pain: A Resting-State Functional Magnetic Resonance Imaging (fMRI) Study

Background

By using functional magnetic resonance imaging (fMRI), we aimed to study the changes in potential brain function network activity in patients with acute eye pain. Also, by using the voxel-wise degree centrality (DC) method, we aimed to explore the relationship between spontaneous brain activity and the clinical features of patients with acute eye pain.

Material/Methods

A total of 15 patients with acute eye pain (5 women and 10 men; EP group) and 15 healthy controls (5 women and 10 men; HC group), were scanned by fMRI. The DC method was used to evaluate changes in spontaneous brain activity. Receiver operating characteristic (ROC) curves were analyzed, and Pearson correlation analysis was used to study the relationship between DC values and clinical manifestations in different regions of brain.

Results

The area of the left limbic lobe showed a reduction in DC value in patients in the EP group. DC values were elevated in the left cerebellum posterior lobe, left inferior parietal lobule, left inferior temporal gyrus, left precuneus, and right cerebellum posterior lobe in the EP group. The visual analog scale value of the eyes in the EP group was negatively correlated with the left limbic lobe signal value and positively correlated with the left inferior parietal lobule signal value. Further, the scores of the hospital anxiety and depression scale and DC value of the left limbic lobe were negatively correlated.

Conclusions

Compared with the HC group, patients with acute eye pain had abnormal patterns of intrinsic brain activity in different brain regions, which may help reveal the potential neural mechanisms involved in eye pain.

The Imbalanced Plasticity Hypothesis of Schizophrenia-Related Psychosis: A Predictive Perspective

A considerable number of studies have attempted to account for the psychotic aspects of schizophrenia in terms of the influential predictive coding (PC) hypothesis. We argue that the prediction-oriented perspective on schizophrenia-related psychosis may benefit from a mechanistic model that: 1) gives due weight to the extent to which alterations in short- and long-term synaptic plasticity determine the degree and the direction of the functional disruption that occurs in psychosis; and 2) addresses the distinction between the two central syndromes of psychosis in schizophrenia: disorganization and reality-distortion. To accomplish these goals, we propose the Imbalanced Plasticity Hypothesis - IPH, and demonstrate that it: 1) accounts for commonalities and differences between disorganization and reality distortion in terms of excessive (hyper) or insufficient (hypo) neuroplasticity, respectively; 2) provides distinct predictions in the cognitive and electrophysiological domains; and 3) is able to reconcile conflicting PC-oriented accounts of psychosis.

Night-sleep Duration Trajectories and Behavior in Preschoolers: Results from a Prospective Birth Cohort Study

Background: Short sleep duration is associated with concomitant behavioral difficulties, but the longitudinal association between sleep duration and later behavior in early childhood remains unclear. The aim was to study the association between sleep duration trajectories throughout preschool and behavior at age 5-6 years.Participants: 1021 children of the French birth-cohort EDEN were included in this study.Methods: Night-sleep duration trajectories were modeled on the basis of repeated measures collected at age 2, 3 and 5-6 years by parental questionnaires. Behavior was assessed with the Strengths and Difficulties Questionnaire (SDQ), with five subscales measuring conduct problems, emotional symptoms, peer relation problems, antisocial behavior, and hyperactivity-inattention problems. The subscales were dichotomized by the 25th percentile. Multivariable logistic regression, adjusted for baseline behavior, and assessment of multiple confounding factors allowed for studying the independent association between night-sleep duration trajectories from age 2 to 5-6 and behavior at age 5-6.Results: Five distinct sleep-duration trajectories were identified. At age 5-6 years, probability of hyperactivity-inattention problems was increased for boys belonging to the "short sleep" and "medium-low sleep" duration trajectory and girls belonging to the "changing sleep" duration trajectory as compared with children with the medium-high sleep duration trajectory (boys: OR 2.69 [95% CI 1.18-6.16], p = .03 and 1.95 [1.25-3.03], p = .003, and girls: OR 2.79 [1.09- 7.17], p = .03). No associations were observed with the other SDQ subscales.Conclusion: The persistence of short night-sleep durations in preschool years as well as a sudden decrease at age 3 are risk factors of hyperactivity-inattention problems at school start.Abbreviations: SS: short-sleep duration trajectory; MLS: medium-low-sleep duration trajectory; MHS: medium-high-sleep duration trajectory; LS: long-sleep duration trajectory; CS: changing-sleep duration trajectory.

Epistemic Injustice in Brain Studies of (Trans)Gender Identity

This study undertakes an analysis of the conceptualization of gender identity in neuroscientific studies of (trans)gender identity that contrast the brains of cisgender and transgender participants. The analysis focuses on instances of epistemic injustice that combine scientific deficiencies and the exclusion of relevant bodies of knowledge. The results of a content analysis show how the ignoring of biosocial, developmental, mosaicist, contextualist, and depathologizing approaches leads to internal conceptual inconsistencies, hermeneutical deficiencies and the upholding of questionable paradigms in the research field. Interviews with researchers involved in these brain studies reveal targeted and diffuse forms of testimonial injustice against alternative approaches, promoted by the hierarchical arrangements of research teams in combination with the careerist and economic logic of research. The analysis points to the exclusion of critical epistemologies of science and the historical oppression of trans people as epistemic agents as the underlying hermeneutical deficiencies.

Compounding Stress: Childhood Adversity as a Risk Factor for Adulthood Trauma Exposure in the Health and Retirement Study

Childhood adversity (CA) and adulthood traumatic experiences (ATEs) are common and unequally distributed in the general population. Early stressors may beget later stressors and alter life-course trajectories of stressor exposure. Gender differences exist regarding the risk of specific stressors. However, few studies have examined the associations between specific types of CA and ATEs. Using a large-scale sample of older adults, we aimed to (a) determine if specific or cumulative CA increased the risk for specific or cumulative ATEs and (b) examine whether these associations were moderated by gender. In a sample from the U.S. Health and Retirement Study (N = 15,717; Mage = 67.57 years, SD = 10.54), cross-sectional Poisson and logistic regression models were fitted to assess the specific and cumulative associations between CA and ATEs. Overall, cumulative CA was associated with a larger risk ratio of ATEs, adjusted for covariates: aRRRs = 1.28, 1.63, and 1.97 for 1, 2, and 3-4 adverse events in childhood, respectively. Cumulative CA was particularly strongly associated with adulthood physical attacks, aOR = 5.66, and having a substance-abusing spouse or child, aOR = 4.00. Childhood physical abuse was the strongest independent risk factor for cumulative ATEs, aRRR = 1.49, and most strongly associated with adulthood physical attacks, aOR = 3.41. Gender moderated the association between cumulative CA and cumulative ATEs, with slightly stronger associations between cumulative CA and ATEs for women than men. Given that CA and ATEs perpetuate health disparities worldwide, reducing their incidence and effects should be major priorities for public health.

Shaping of the Female Human Brain by Sex Hormones: A Review

Traditionally sex hormones have been associated with reproductive and developmental processes only. Since the 1950s we know that hormones can have organizational effects on the developing brain and initiate hormonal transition periods such as puberty. However, recent evidence shows that sex hormones additionally structure the brain during important hormonal transition periods across a woman's life including short-term fluctuations during the menstrual cycle. However, a comprehensive review focusing on structural changes during all hormonal transition phases of women is still missing. Therefore, in this review structural changes across hormonal transition periods (i.e., puberty, menstrual cycle, oral contraceptive intake, pregnancy and menopause) were investigated in a structured way and correlations with sex hormones evaluated. Results show an overall reduction in grey matter and region-specific decreases in prefrontal, parietal and middle temporal areas during puberty. Across the menstrual cycle grey matter plasticity in the hippocampus, the amygdala as well as temporal and parietal regions were most consistently reported. Studies reporting on pre- and post-pregnancy measurements revealed volume reductions in midline structures as well as prefrontal and temporal cortices. During perimenopause, the decline in sex hormones was paralleled with a reduction in hippocampal and parietal cortex volume. Brain volume changes were significantly correlated with estradiol, testosterone and progesterone levels in some studies, but directionality remains inconclusive between studies. These results indicate that sex hormones play an important role in shaping women's brain structure during different transition periods and are not restricted to specific developmental periods.

Diagnostic classification of autism using resting-state fMRI data improves with full correlation functional brain connectivity compared to partial correlation

BACKGROUND

Autism Spectrum Disorder (ASD) is a neurodevelopmental disability with altered connectivity in brain networks.

NEW METHOD

In this study, brain connections in Resting-state functional Magnetic Resonance Imaging (Rs-fMRI) of ASD and Typical Developing (TD) are analyzed by partial and full correlation methods such as Gaussian Graphical Least Absolute Shrinkage and Selection Operator (GLASSO), Max-Det Matrix Completion (MDMC), and Pearson Correlation Co-Efficient (PCCE). We investigated Functional Connectivity (FC) of ASD and TD brain from 238 functionally defined regions of interest. Furthermore, we constructed a series of feature sets by applying conditional random forests and conditional permutation importance. We built classifier models by Random Forest (RF), Oblique RF (ORF), Support Vector Machine (SVM), and Convolutional Neural Network (CNN) for each feature set. FC features are ranked based on p-value and we analyzed the top 20 FC features.

RESULTS

We achieved a single-trial test accuracy of 72.5 %, though MDMC-SVM and PCCE-CNN pipelines. Further, PCCE-CNN pipeline gives better average test accuracy (70.31 %) and area under the curve (0.73) compared to other pipelines. We found that top-20 PCCE based FC features are from networks such as Dorsal Attention (DA), Cingulo-Opercular Task Control (COTC), somatosensory motor hand and subcortical. In addition, among top 20 PCCE features, many FC links are found between COTC and DA (4 connections) which helped to discriminate the ASD and TD.

COMPARISON WITH EXISTING METHODS AND CONCLUSIONS

The generalized classifier models built in our study for highly heterogeneous participants perform better than previous studies with similar data sets and diagnostic groups.

Hippocampal formation volume, its subregions, and its specific contributions to visuospatial memory tasks

Visuospatial memory (VSM) is the ability to represent and manipulate visual and spatial information. This cognitive function depends on the functioning of the hippocampal formation (HF), located in the medial portion of the temporal cortex. The present study aimed to investigate whether there is an association between the volume of the HF and performance in VSM tests. High-resolution structural images (T1) and neuropsychological tests evaluating VSM were performed on 31 healthy individuals. A VSM index was created by grouping 5 variables from 5 tasks (4 from the CANTAB battery and 1 from the Rey-Osterrieth Complex Figure test). Multiple linear regression models using the volumes of HF subregions as independent variables and the VSM index as the dependent variable were conducted to test the hypothesis that memory performance could be predicted by HF volumes. We also conducted analyses to explore the role of covariates that may mediate this relationship, specifically age and intelligence quotient (IQ). We found significant associations between the hippocampal subregions of the left hemisphere and the VSM index (F(7,22)=2.758, P=0.032, R2a=0.298). When IQ was accounted for as a covariate, we also found significant results for the right hemisphere (F(8,21)=2.804, P=0.028, R2a=0.517). We concluded that the bilateral hippocampal formations contributed to performance on VSM tasks. Also, VSM processing is essential for a diverse set of daily activities and may be influenced by demographic variables in healthy subjects.

Long-term outcomes of survivors of neonatal insults: A systematic review and meta-analysis

BACKGROUND

The Millennium Developmental Goals ensured a significant reduction in childhood mortality. However, this reduction simultaneously raised concerns about the long-term outcomes of survivors of early childhood insults. This systematic review focuses on the long-term neurocognitive and mental health outcomes of neonatal insults (NNI) survivors who are six years or older.

METHODS

Two independent reviewers conducted a comprehensive search for empirical literature by combining index and free terms from the inception of the databases until 10th October 2019. We also searched for additional relevant literature from grey literature and using reference tracking. Studies were included if they: were empirical studies conducted in humans; the study participants were followed at six years of age or longer; have an explicit diagnosis of NNI, and explicitly define the outcome and impairment. Medians and interquartile range (IQR) of the proportions of survivors of the different NNI with any impairment were calculated. A random-effect model was used to explore the estimates accounted for by each impairment domain.

RESULTS

Fifty-two studies with 94,978 participants who survived NNI were included in this systematic review. The overall prevalence of impairment in the survivors of NNI was 10.0% (95% CI 9.8-10.2). The highest prevalence of impairment was accounted for by congenital rubella (38.8%: 95% CI 18.8-60.9), congenital cytomegalovirus (23.6%: 95% CI 9.5-41.5), and hypoxic-ischemic encephalopathy (23.3%: 95% CI 14.7-33.1) while neonatal jaundice has the lowest proportion (8.6%: 95% CI 2.7-17.3). The most affected domain was the neurodevelopmental domain (16.6%: 95% CI 13.6-19.8). The frequency of impairment was highest for neurodevelopmental impairment [22.0% (IQR = 9.2-24.8)] and least for school problems [0.0% (IQR = 0.0-0.00)] in any of the conditions.

CONCLUSION

The long-term impact of NNI is also experienced in survivors of NNI who are 6 years or older, with impairments mostly experienced in the neurodevelopmental domain. However, there are limited studies on long-term outcomes of NNI in sub-Saharan Africa despite the high burden of NNI in the region.

TRIAL REGISTRATION

Registration number: CRD42018082119.

Performance anxiety and the plasticity of emotional responses

Current psychological theories of performance anxiety focus heavily on relating performers' physiological and mental states to their abilities to maintain focus and execute learned skills. How task-specific expertise and past experiences moderate the degree to which individuals become anxious in a given performance context are not well accounted for within these theories. This review considers how individual differences arising from learning may shape the psychobiological, emotional, and cognitive processes that modulate anxious states associated with the performance of highly trained skills. Current approaches to understanding performance anxiety are presented, followed by a critique of these approaches. A connectionist model is proposed as an alternative approach to characterising performance anxiety by viewing performers' anxious states at a specific time point as jointly determined by experience-dependent plasticity, competition between motivational systems, and ongoing cognitive and somatic states. Clarifying how experience-dependent plasticity contributes to the emergence of socio-evaluative anxiety in challenging situations can not only help performers avoid developing maladaptive emotional responses, but may also provide new clues about how memories of past events and imagined future states interact with motivational processes to drive changes in emotional states and cognitive processing.

Mechanisms linking childhood trauma exposure and psychopathology: a transdiagnostic model of risk and resilience

BACKGROUND

Transdiagnostic processes confer risk for multiple types of psychopathology and explain the co-occurrence of different disorders. For this reason, transdiagnostic processes provide ideal targets for early intervention and treatment. Childhood trauma exposure is associated with elevated risk for virtually all commonly occurring forms of psychopathology. We articulate a transdiagnostic model of the developmental mechanisms that explain the strong links between childhood trauma and psychopathology as well as protective factors that promote resilience against multiple forms of psychopathology.

MAIN BODY

We present a model of transdiagnostic mechanisms spanning three broad domains: social information processing, emotional processing, and accelerated biological aging. Changes in social information processing that prioritize threat-related information-such as heightened perceptual sensitivity to threat, misclassification of negative and neutral emotions as anger, and attention biases towards threat-related cues-have been consistently observed in children who have experienced trauma. Patterns of emotional processing common in children exposed to trauma include elevated emotional reactivity to threat-related stimuli, low emotional awareness, and difficulties with emotional learning and emotion regulation. More recently, a pattern of accelerated aging across multiple biological metrics, including pubertal development and cellular aging, has been found in trauma-exposed children. Although these changes in social information processing, emotional responding, and the pace of biological aging reflect developmental adaptations that may promote safety and provide other benefits for children raised in dangerous environments, they have been consistently associated with the emergence of multiple forms of internalizing and externalizing psychopathology and explain the link between childhood trauma exposure and transdiagnostic psychopathology. Children with higher levels of social support, particularly from caregivers, are less likely to develop psychopathology following trauma exposure. Caregiver buffering of threat-related processing may be one mechanism explaining this protective effect.

CONCLUSION

Childhood trauma exposure is a powerful transdiagnostic risk factor associated with elevated risk for multiple forms of psychopathology across development. Changes in threat-related social and emotional processing and accelerated biological aging serve as transdiagnostic mechanisms linking childhood trauma with psychopathology. These transdiagnostic mechanisms represent critical targets for early interventions aimed at preventing the emergence of psychopathology in children who have experienced trauma.

The Impact of Traumatic Injury to the Immature Human Brain: A Scoping Review with Insights from Advanced Structural Neuroimaging

Traumatic brain injury (TBI) during critical periods of early-life brain development can affect the normal formation of brain networks responsible for a range of complex social behaviors. Because of the protracted nature of brain and behavioral development, deficits in cognitive and socioaffective behaviors may not become evident until late adolescence and early adulthood, when such skills are expected to reach maturity. In addition, multiple pre- and post-injury factors can interact with the effects of early brain insult to influence long-term outcomes. In recent years, with advancements in magnetic-resonance-based neuroimaging techniques and analysis, studies of the pediatric population have revealed a link between neurobehavioral deficits, such as social dysfunction, with white matter damage. In this review, in which we focus on contributions from Australian researchers to the field, we have highlighted pioneering longitudinal studies in pediatric TBI, in relation to social deficits specifically. We also discuss the use of advanced neuroimaging and novel behavioral assays in animal models of TBI in the immature brain. Together, this research aims to understand the relationship between injury consequences and ongoing brain development after pediatric TBI, which promises to improve prediction of the behavioral deficits that emerge in the years subsequent to early-life injury.

Language development and brain reorganization in a child born without the left hemisphere

We present a case of a 14-year-old girl born without the left hemisphere due to prenatal left internal carotid occlusion. We combined longitudinal language and cognitive assessments with functional and structural neuroimaging data to situate the case within age-matched, typically developing children. Despite having had a delay in getting language off the ground during the preschool years, our case performed within the normal range on a variety of standardized language tests, and exceptionally well on phonology and word reading, during the elementary and middle school years. Moreover, her spatial, number, and reasoning skills also fell in the average to above-average range based on assessments during these time periods. Functional MRI data revealed activation in right fronto-temporal areas when listening to short stories, resembling the bilateral activation patterns in age-matched typically developing children. Diffusion MRI data showed significantly larger dorsal white matter association tracts (the direct and anterior segments of the arcuate fasciculus) connecting areas active during language processing in her remaining right hemisphere, compared to either hemisphere in control children. We hypothesize that these changes in functional and structural brain organization are the result of compensatory brain plasticity, manifesting in unusually large right dorsal tracts, and exceptional performance in phonology, speech repetition, and decoding. More specifically, we posit that our case's large white matter connections might have played a compensatory role by providing fast and reliable transfer of information between cortical areas for language in the right hemisphere.

Post-stroke remodeling processes in animal models and humans

After cerebral ischemia, events like neural plasticity and tissue reorganization intervene in lesioned and non-lesioned areas of the brain. These processes are tightly related to functional improvement and successful rehabilitation in patients. Plastic remodeling in the brain is associated with limited spontaneous functional recovery in patients. Improvement depends on the initial deficit, size, nature and localization of the infarction, together with the sex and age of the patient, all of them affecting the favorable outcome of reorganization and repair of damaged areas. A better understanding of cerebral plasticity is pivotal to design effective therapeutic strategies. Experimental models and clinical studies have fueled the current understanding of the cellular and molecular processes responsible for plastic remodeling. In this review, we describe the known mechanisms, in patients and animal models, underlying cerebral reorganization and contributing to functional recovery after ischemic stroke. We also discuss the manipulations and therapies that can stimulate neural plasticity. We finally explore a new topic in the field of ischemic stroke pathophysiology, namely the brain-gut axis.

Real-Time Auditory Feedback-Induced Adaptation to Walking Among Seniors Using the Heel2Toe Sensor: Proof-of-Concept Study

Background

Evidence shows that gait training in older adults is effective in improving the gait pattern, but the effects abate with cessation of training. During gait training, therapists use a number of verbal and visual cues to place the heel first when stepping. This simple strategy changes posture from stooped to upright, lengthens the stride, stimulates pelvic and trunk rotation, and facilitates arm swing. These principles guided the development of the Heel2Toe sensor that provides real-time auditory feedback for each good step, in which the heel strikes first.

Objective

This feasibility study aimed (1) to contribute evidence toward the feasibility and efficacy potential for home use of the Heel2Toe sensor that provides real-time feedback and (2) to estimate changes in gait parameters after five training sessions using the sensor.

Methods

A pre-post study included 5 training sessions over 2 weeks in the community on a purposive sample of six seniors. Proportion of good steps, angular velocity (AV) at each step, and cadence over a 2- minute period were assessed as was usability and experience.

Results

All gait parameters, proportion of good steps, AV, and duration of walking bouts improved. The coefficient of variation of AV decreased, indicating consistency of stepping.

Conclusions

Efficacy potential and feasibility of the Heel2Toe sensor were demonstrated.

Hypothermia: Impact on plasticity following brain injury

Therapeutic hypothermia (TH) is a potent neuroprotectant against multiple forms of brain injury, but in some cases, prolonged cooling is needed. Such cooling protocols raise the risk that TH will directly or indirectly impact neuroplasticity, such as after global and focal cerebral ischemia or traumatic brain injury. TH, depending on the depth and duration, has the potential to broadly affect brain plasticity, especially given the spatial, temporal, and mechanistic overlap with the injury processes that cooling is used to treat. Here, we review the current experimental and clinical evidence to evaluate whether application of TH has any adverse or positive effects on postinjury plasticity. The limited available data suggest that mild TH does not appear to have any deleterious effect on neuroplasticity; however, we emphasize the need for additional high-quality preclinical and clinical work in this area.

Visual Field Advantage: Redefined by Training?

Previc (1990) postulated that most peri-personal space interactions occurred in the lower visual field (LVF), leading to an advantage when compared to the upper visual field (UVF). It is not clear if extensive practice can affect the difference between interactions in the LVF/UVF. We tested male and female basketball varsity athletes and non-athletes on a DynaVision D2 visuomotor reaction task. We recruited basketball players because in their training they spend significant amount of time processing UVF information. We found a LVF advantage in all participants, but this advantage was significantly reduced in the athletes. The results suggest that training can be a powerful modulator of visuomotor function.

Rehabilitation-induced brain changes detected through magnetic resonance imaging in children with neurodevelopmental disorders: A systematic review

AIM

The aim of this study was to systematically review evidence about rehabilitation-induced neuroplasticity measured by magnetic resonance imaging (MRI) in children with neurodevelopmental disorders.

METHOD

The following databases were searched: MEDLINE, EMBASE, CINAHL, and PsycINFO. Two independent reviewers screened articles according to inclusion criteria: (1) peer-review study published in a scientific journal; (2) studies that evaluated a rehabilitation-based intervention; (3) participants aged less than 19 years with a neurodevelopmental disorder; and (4) studies that used at least one MRI modality as an outcome measure. Twenty-seven studies met the criteria for the review and their quality was assessed by two independent reviewers using the Effective Public Health Practice Project Quality Assessment Tool.

RESULTS

Based on an assessment of bias and overall quality, 11% of the papers were rated as strong; 30% moderate; and 59% weak. Outcomes were categorized into structural connectivity, functional connectivity, cortical activation, and structural volume. Cortical activation and structural connectivity were the most commonly reported measures. Most studies were able to identify brain changes in children with neurodevelopmental disorders after therapy.

INTERPRETATIONS

Rehabilitation is shown to induce MRI-detectable neuroplastic changes in children with neurodevelopmental disorders. Structural connectivity might need greater intensity and/or duration of intervention to induce change.