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Diffusion Spectrum Imaging (DSI) using dense Cartesian sampling of q‐space has been shown to provide important advantages for modeling complex white matter architecture. However, its adoption has been limited by the lengthy acquisition time required. Sparser sampling of q‐space combined with compressed sensing (CS) reconstruction techniques has been proposed as a way to reduce the scan time of DSI acquisitions. However prior studies have mainly evaluated CS‐DSI in post‐mortem or non‐human data. At present, the capacity for CS‐DSI to provide accurate and reliable measures of white matter anatomy and microstructure in the living human brain remains unclear. We evaluated the accuracy and inter‐scan reliability of 6 different CS‐DSI schemes that provided up to 80% reductions in scan time compared to a full DSI scheme. We capitalized on a dataset of 26 participants who were scanned over eight independent sessions using a full DSI scheme. From this full DSI scheme, we subsampled images to create a range of CS‐DSI images. This allowed us to compare the accuracy and inter‐scan reliability of derived measures of white matter structure (bundle segmentation, voxel‐wise scalar maps) produced by the CS‐DSI and the full DSI schemes. We found that CS‐DSI estimates of both bundle segmentations and voxel‐wise scalars were nearly as accurate and reliable as those generated by the full DSI scheme. Moreover, we found that the accuracy and reliability of CS‐DSI was higher in white matter bundles that were more reliably segmented by the full DSI scheme. As a final step, we replicated the accuracy of CS‐DSI in a prospectively acquired dataset (n = 20, scanned once). Together, these results illustrate the utility of CS‐DSI for reliably delineating in vivo white matter architecture in a fraction of the scan time, underscoring its promise for both clinical and research applications. [ABSTRACT FROM AUTHOR]

Preclinical evidence suggests that inter‐individual variation in the structure of the hypothalamus at birth is associated with variation in the intrauterine environment, with downstream implications for future disease susceptibility. However, scientific advancement in humans is limited by a lack of validated methods for the automatic segmentation of the newborn hypothalamus. N = 215 healthy full‐term infants with paired T1‐/T2‐weighted MR images across four sites were considered for primary analyses (mean postmenstrual age = 44.3 ± 3.5 weeks, nmale/nfemale = 110/106). The outputs of FreeSurfer's hypothalamic subunit segmentation tools designed for adults (segFS) were compared against those of a novel registration‐based pipeline developed here (segATLAS) and against manually edited segmentations (segMAN) as reference. Comparisons were made using Dice Similarity Coefficients (DSCs) and through expected associations with postmenstrual age at scan. In addition, we aimed to demonstrate the validity of the segATLAS pipeline by testing for the stability of inter‐individual variation in hypothalamic volume across the first year of life (n = 41 longitudinal datasets available). SegFS and segATLAS segmentations demonstrated a wide spread in agreement (mean DSC = 0.65 ± 0.14 SD; range = {0.03–0.80}). SegATLAS volumes were more highly correlated with postmenstrual age at scan than segFS volumes (n = 215 infants; RsegATLAS2 = 65% vs. RsegFS2 = 40%), and segATLAS volumes demonstrated a higher degree of agreement with segMAN reference segmentations at the whole hypothalamus (segATLAS DSC = 0.89 ± 0.06 SD; segFS DSC = 0.68 ± 0.14 SD) and subunit levels (segATLAS DSC = 0.80 ± 0.16 SD; segFS DSC = 0.40 ± 0.26 SD). In addition, segATLAS (but not segFS) volumes demonstrated stability from near birth to ~1 years age (n = 41; R2 = 25%; p < 10−3). These findings highlight segATLAS as a valid and publicly available (https://github.com/jerodras/neonate%5fhypothalamus%5fseg) pipeline for the segmentation of hypothalamic subunits using human newborn MRI up to 3 months of age collected at resolutions on the order of 1 mm isotropic. Because the hypothalamus is traditionally understudied due to a lack of high‐quality segmentation tools during the early life period, and because the hypothalamus is of high biological relevance to human growth and development, this tool may stimulate developmental and clinical research by providing new insight into the unique role of the hypothalamus and its subunits in shaping trajectories of early life health and disease. [ABSTRACT FROM AUTHOR]

Individual differences in cognitive abilities emerge early during development, and children with poorer cognition are at increased risk for adverse outcomes as they enter adolescence. Caregiving plays an important role in supporting cognitive development, yet it remains unclear how specific types of caregiving behaviors may shape cognition, highlighting the need for large‐scale studies. In the present study, we characterized replicable yet specific associations between caregiving behaviors and cognition in two large sub‐samples of children ages 9—10 years old from the Adolescent Brain Cognitive Development Study® (ABCD). Across both discovery and replication sub‐samples, we found that child reports of caregiver monitoring (supervision or regular knowledge of the child's whereabouts) were positively associated with general cognition abilities, after covarying for age, sex, household income, neighborhood deprivation, and parental education. This association was specific to the type of caregiving behavior (caregiver monitoring, but not caregiver warmth), and was most strongly associated with a broad domain of general cognition (but not executive function or learning/memory). Additionally, we found that caregiver monitoring partially mediated the association between household income and cognition, furthering our understanding of how socioeconomic disparities may contribute to disadvantages in cognitive development. Together, these findings underscore the influence of differences in caregiving behavior in shaping youth cognition. Research Highlights: Caregiver monitoring, but not caregiver warmth, is associated with cognitive performance in youthCaregiver monitoring partially mediates the association between household income and cognitionResults replicated across two large matched samples from the Adolescent Brain Cognitive Development Study® (ABCD) [ABSTRACT FROM AUTHOR]

We previously showed that dual‐task cost (DTC) on gait speed in people with Parkinson's disease (PD) improved after 6 weeks of the Agility Boot Camp with Cognitive Challenge (ABC‐C) exercise program. Since deficits in dual‐task gait speed are associated with freezing of gait and gray matter atrophy, here we performed preplanned secondary analyses to answer two questions: (a) Do people with PD who are freezers present similar improvements compared to nonfreezers in DTC on gait speed with ABC‐C? (b) Can cortical thickness at baseline predict responsiveness to the ABC‐C? The DTC from 39 freezers and 43 nonfreezers who completed 6 weeks of ABC‐C were analyzed. A subset of 51 participants (21 freezers and 30 nonfreezers) with high quality imaging data were used to characterize relationships between baseline cortical thickness and delta (Δ) DTC on gait speed following ABC‐C. Freezers showed larger ΔDTC on gait speed than nonfreezers with ABC‐C program (p <.05). Cortical thickness in visual and fronto‐parietal areas predicted ΔDTC on gait speed in freezers, whereas sensorimotor‐lateral thickness predicted ΔDTC on gait speed in nonfreezers (p <.05). When matched for motor severity, visual cortical thickness was a common predictor of response to exercise in all individuals, presenting the largest effect size. In conclusion, freezers improved gait automaticity even more than nonfreezers from cognitively challenging exercise. DTC on gait speed improvement was associated with larger baseline cortical thickness from different brain areas, depending on freezing status, but visual cortex thickness showed the most robust relationship with exercise‐induced improvements in DTC. [ABSTRACT FROM AUTHOR]

Preclinical studies demonstrate that chronic stress modulates the effects of oestradiol (E2) on behaviour through the modification of the amygdala and the medial prefrontal cortex (mPFC) neuronal structure. Clinical studies suggest that alterations in amygdala functional connectivity (FC) with the mPFC may be associated with stress‐related phenotypes, including mood and anxiety disorders. Thus, identifying the effects of stress and E2 on amygdala‐mPFC circuits is critical for understanding the neurobiology underpinning the vulnerability to stress‐related disorders in women. In the present study, we used a well‐validated rhesus monkey model of chronic psychosocial stress (subordinate social rank) to examine effects of E2 on subordinate (SUB) (i.e. high stress) and dominant (DOM) (i.e. low stress) female resting‐state amygdala FC with the mPFC and with the whole‐brain. In the non‐E2 treatment control condition, SUB was associated with stronger left amygdala FC to subgenual cingulate (Brodmann area [BA] 25: BA25), a region implicated in several psychopathologies in people. In SUB females, E2 treatment strengthened right amygdala‐BA25 FC, induced a net positive amygdala‐visual cortex FC that was positively associated with frequency of submissive behaviours, and weakened positive amygdala‐para/hippocampus FC. Our findings show that subordinate social rank alters amygdala FC and the impact of E2 on amygdala FC with BA25 and with regions involved in visual processing and memory encoding. [ABSTRACT FROM AUTHOR]

Background: A central nosological problem concerns the etiological relationship of emotional dysregulation with ADHD. Molecular genetic risk scores provide a novel method for informing this question. Methods: Participants were 514 community‐recruited children of Northern European descent age 7‐11 defined as ADHD or non‐ADHD by detailed research evaluation. Parents‐rated ADHD on standardized ratings and child temperament on the Temperament in Middle Childhood Questionnaire (TMCQ) and reported on ADHD and comorbid disorders by semi‐structured clinical interview. Categorical and dimensional variables were created for ADHD, emotional dysregulation (implicating disruption of regulation of both anger‐irritability and of positive valence surgency‐sensation seeking), and irritability alone (anger dysregulation). Genome‐wide polygenic risk scores (PRS) were computed for ADHD and depression genetic liability. Structural equation models and computationally derived emotion profiles guided analysis. Results: The ADHD PRS was associated in variable‐centered analyses with irritability (β =.179, 95% CI = 0.087–0.280; ΔR2 =.034, p <.0002), but also with surgency/sensation seeking (B =.146, 95%CI = 0.052–0.240, ΔR2=.022, p =.002). In person‐centered analysis, the ADHD PRS was elevated in the emotion dysregulation ADHD group versus other ADHD children (OR = 1.44, 95% CI = 1.03–2.20, Nagelkerke ΔR2 =.013, p =.033) but did not differentiate irritable from surgent ADHD profiles. All effects were independent of variation in ADHD severity across traits or groups. The depression PRS was related to oppositional defiant disorder but not to ADHD emotion dysregulation. Conclusions: Irritability‐anger and surgency‐sensation seeking, as forms of negative and positively valenced dysregulated affect in ADHD populations, both relate principally to ADHD genetic risk and not mood‐related genetic risk. [ABSTRACT FROM AUTHOR]

Abstract: Developmental scientists have examined the independent effects of peer presence, social cues, and rewards on adolescent decision‐making and cognitive control. Yet, these contextual factors often co‐occur in real world social situations. The current study examined the combined effects of all three factors on cognitive control, and its underlying neural circuitry, using a task to better capture adolescents' real world social interactions. A sample of 176 participants ages 13–25, was scanned while performing an adapted go/no‐go task alone or in the presence of a virtual peer. The task included brief positive social cues and sustained periods of positive arousal. Adolescents showed diminished cognitive control to positive social cues when anticipating a reward in the presence of peers relative to when alone, a pattern not observed in older participants. This behavioral pattern was paralleled by enhanced orbitofrontal activation. The results demonstrate the synergistic impact of social and reward influences on cognitive control in adolescents. [ABSTRACT FROM AUTHOR]

Aims To identify atypical brain functional connectivity in women with UUI and detrusor overactivity (DO) and to predict the presence/severity of UUI in individual women using connectivity features. Methods This is a cross-sectional study comparing brain functional connectivity in women with and without UUI. Validated symptom/quality of life questionnaires were used for phenotyping. Participants are females between ages 40 and 85 with daily UUI with DO (Cases, N = 16) and without UUI (Controls, N = 24). Functional MRI and Resting state connectivity MRI were obtained at empty/ full bladder. Multivariate pattern analysis (MVPA) was used to predict the presence and severity of UUI from connectivity data. Results There are significant differences in brain activation between cases and controls in eighteen brain regions irrespective of empty or full bladder. These include regions involved in attention (inferior partietal), decision making (inferior and superior frontal gyrus), primary motor and sensory (precentral and postcentral gyrus) functions. Women with UUI showed no change in connectivity with bladder filling in regions involved in interoception (insula), integration of afferent function (anterior cingulate), and decision making (middle frontal). MVPA of connectivity data showed robust classification of an individual woman as case or control (89% sensitivity, 83% specificity). Six connectivity features accurately predicted disease severity (R2 = 0.81). Conclusion We identified two mechanisms of abnormal bladder control, one involving atypical activation of brain regions, and another atypical functional integration across sensory, emotional, cognitive and motor regions. Connectivity information is robust enough to classify an individual as having UUI or not and to predict symptom severity. Neurourol. Urodynam. 35:564-573, 2016. © 2015 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Background Extensive animal research has demonstrated the vulnerability of the brain to early life stress ( ELS) with consequences for emotional development and mental health. However, the influence of moderate and common forms of stress on early human brain development is less well-understood and precisely characterized. To date, most work has focused on severe forms of stress, and/or on brain functioning years after stress exposure. Methods In this report we focused on conflict between parents (interparental conflict), a common and relatively moderate form of ELS that is highly relevant for children's mental health outcomes. We used resting state functional connectivity MRI to examine the coordinated functioning of the infant brain ( N = 23; 6-12-months-of-age) in the context of interparental conflict. We focused on the default mode network ( DMN) due to its well-characterized developmental trajectory and implications for mental health. We further examined DMN strength as a mediator between conflict and infants' negative emotionality. Results Higher interparental conflict since birth was associated with infants showing stronger connectivity between two core DMN regions, the posterior cingulate cortex ( PCC) and the anterior medial prefrontal cortex ( aMPFC). PCC to amygdala connectivity was also increased. Stronger PCC- aMPFC connectivity mediated between higher conflict and higher negative infant emotionality. Conclusions The developing DMN may be an important marker for effects of ELS with relevance for emotional development and subsequent mental health. Increasing understanding of the associations between common forms of family stress and emerging functional brain networks has potential to inform intervention efforts to improve mental health outcomes. [ABSTRACT FROM AUTHOR]

Background Functional connectivity MRI is an emerging technique that can be used to investigate typical and atypical brain function in developing and aging populations. Despite some of the current confounds in the field of functional connectivity MRI, the translational potential of the technique available to investigators may eventually be used to improve diagnosis, early disease detection, and therapy monitoring. Method and Scope Based on a comprehensive survey of the literature, this review offers an introduction of resting-state functional connectivity for new investigators to the field of resting-state functional connectivity. We discuss a brief history of the technique, various methods of analysis, the relationship of functional networks to behavior, as well as the translational potential of functional connectivity MRI to investigate neuropsychiatric disorders. We also address some considerations and limitations with data analysis and interpretation. Conclusions The information provided in this review should serve as a foundation for investigators new to the field of resting-state functional connectivity. The discussion provides a means to better understand functional connectivity and its application to typical and atypical brain function. [ABSTRACT FROM AUTHOR]

Attention-deficit/hyperactive disorder (ADHD) and autism spectrum disorders (ASD) are two of the most common and vexing neurodevelopmental disorders among children. Although the two disorders share many behavioral and neuropsychological characteristics, most MRI studies examine only one of the disorders at a time. Using graph theory combined with structural and functional connectivity, we examined the large-scale network organization among three groups of children: a group with ADHD (8-12 years, n = 20), a group with ASD (7-13 years, n = 16), and typically developing controls (TD) (8-12 years, n = 20). We apply the concept of the rich-club organization, whereby central, highly connected hub regions are also highly connected to themselves. We examine the brain into two different network domains: (1) inside a rich-club network phenomena and (2) outside a rich-club network phenomena. The ASD and ADHD groups had markedly different patterns of rich club and non rich-club connections in both functional and structural data. The ASD group exhibited higher connectivity in structural and functional networks but only inside the rich-club networks. These findings were replicated using the autism brain imaging data exchange dataset with ASD ( n = 85) and TD ( n = 101). The ADHD group exhibited a lower generalized fractional anisotropy and functional connectivity inside the rich-club networks, but a higher number of axonal fibers and correlation coefficient values outside the rich club. Despite some shared biological features and frequent comorbity, these data suggest ADHD and ASD exhibit distinct large-scale connectivity patterns in middle childhood. Hum Brain Mapp 35:6032-6048, 2014. © 2014 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Background Even in the absence of heavy alcohol use, youth with familial alcoholism (family history positive [FHP]) exhibit atypical brain functioning and behavior. Although emotional and cognitive systems are affected in alcohol use disorders ( AUDs), little attention has focused on whether brain and behavior phenotypes related to the interplay between affective and executive functioning may be a premorbid risk factor for the development of AUDs in FHP youth. Methods Twenty-four FHP and 22 family history negative (FHN) 12- to 16-year-old adolescents completed study procedures. After exclusion of participants with clinically significant depressive symptoms and those who did not meet performance criteria during an Emotional Go-NoGo task, 19 FHP and 17 FHN youth were included in functional magnetic resonance imaging ( fMRI) analyses. Resting state functional connectivity MRI, using amygdalar seed regions, was analyzed in 16 FHP and 18 FHN youth, after exclusion of participants with excessive head movement. Results fMRI showed that brain activity in FHP youth, compared with FHN peers, was reduced during emotional processing in the superior temporal cortex, as well as during cognitive control within emotional contexts in frontal and striatal regions. Group differences in resting state amygdalar connectivity were seen bilaterally between FHP and FHN youth. In FHP youth, reduced resting state synchrony between the left amygdala and left superior frontal gyrus was related to poorer response inhibition, as measured during the fMRI task. Conclusions To our knowledge, this is the first study to examine emotion-cognition interactions and resting state functional connectivity in FHP youth. Findings from this research provide insight into neural and behavioral phenotypes associated with emotional processing in familial alcoholism, which may relate to increased risk of developing AUDs. [ABSTRACT FROM AUTHOR]

Aims This aim of this study is to identify the brain mechanisms involved in bladder control. Methods We used fMRI to identify brain regions that are activated during bladder filling. We then used resting state connectivity fMRI (rs-fcMRI) to assess functional connectivity of regions identified by fMRI with the rest of the brain as the bladder is filled to capacity. Results Female participants (n = 20) were between ages 40 and 64 with no significant history of symptomatic urinary incontinence. Main effect of time (MET) fMRI analysis resulted in 20 regions of interest (ROIs) that have significant change in BOLD signal (z = 3.25, P <0.05) over the course of subtle bladder filling and emptying regardless of full versus empty bladder state. Bladder-state by time (BST) fMRI analysis resulted in three ROIs that have significant change in BOLD signal (z = 3.25, P <0.05) over the course of bladder runs comparing full versus empty bladder state. Rs-fcMRI fixed effects analysis identified significant changes in connectivity between full and empty bladder states in seven brain regions (z = 4.0) using the three BST ROIs and sixteen brain regions (z = 7) using the twenty MET ROIs. Regions identified include medial frontal gyrus, posterior cingulate (PCC), inferiolateral temporal and post-central gyrus, amygdale, the caudate, inferior parietal lobe as well as anterior and middle cingulate gyrus. Conclusions There is significant and vast changes in the brain's functional connectivity when bladder is filled suggesting that the central process responsible for the increased control during the full bladder state appears to largely rely on the how distributed brain systems are functionally integrated. Neurourol. Urodynam. 33:493-501, 2014. © 2013 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Vértes and Bullmore's article lays a framework for applying connectomics, the study of brain function from the perspective of underlying network organization, to advance understanding of healthy and maladaptive brain development. They elucidate the power of connectomics for bridging both different levels of analysis (e.g. from synapses to brain regions) and multiple academic fields. In this commentary, we highlight important themes and remaining questions stemming from Vértes and Bullmore's work, including: (a) the application of connectomics in the context of integrating analyses across multiple spatial and temporal dimensions, (b) the extent to which connectomics might be applied in translational and clinical studies of development, (c) growth connectomics and the Developmental Origins of Health and Disease ( DOHaD) hypothesis, and (d) the importance and complexity of sound methodological practices in applying connectomics to developmental and clinical science. Ongoing work in these areas will be important for fulfilling the promise of connectomics as a bridge between neuroscience, developmental science, and translational and clinical research. [ABSTRACT FROM AUTHOR]