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1.
medRxiv ; 2024 Jun 18.
Article in English | MEDLINE | ID: mdl-38562872

ABSTRACT

Widely prescribed for Attention-Deficit/Hyperactivity Disorder (ADHD), stimulants (e.g., methylphenidate) have been studied for their chronic effects on the brain in prospective designs controlling dosage and adherence. While controlled approaches are essential, they do not approximate real-world stimulant exposure contexts where medication interruptions, dosage non-compliance, and polypharmacy are common. Brain changes in real-world conditions are largely unexplored. To fill this gap, we capitalized on the observational design of the Adolescent Brain Cognitive Development (ABCD) study to examine effects of stimulants on large-scale bilateral cortical networks' resting-state functional connectivity (rs-FC) with 6 striatal regions (left and right caudate, putamen, and nucleus accumbens) across two years in children with ADHD. Bayesian hierarchical regressions revealed associations between stimulant exposure and change in rs-FC of multiple striatal-cortical networks, affiliated with executive and visuo-motor control, which were not driven by general psychotropic medication. Of these connections, three were selective to stimulants versus stimulant naive: reduced rs-FC between caudate and frontoparietal network, and between putamen and frontoparietal and visual networks. Comparison with typically developing children in the ABCD sample revealed stronger rs-FC reduction in stimulant-exposed children for putamen and frontoparietal and visual networks, suggesting a normalizing effect of stimulants. 14% of stimulant-exposed children demonstrated reliable reduction in ADHD symptoms, and were distinguished by stronger rs-FC reduction between right putamen and visual network. Thus, stimulant exposure for a two-year period under real-world conditions modulated striatal-cortical functional networks broadly, had a normalizing effect on a subset of networks, and was associated with potential therapeutic effects involving visual attentional control.

2.
Autism ; : 13623613241246091, 2024 Apr 20.
Article in English | MEDLINE | ID: mdl-38642028

ABSTRACT

LAY ABSTRACT: Many autistic people struggle with mental health problems like anxiety, depression, inattention, and aggression, which can be challenging to treat. Executive function challenges, which impact many autistic individuals, may serve as a risk factor for mental health problems or make treating mental health conditions more difficult. While some people respond well to medication or therapy, others do not. This study tried to understand if there are different subgroups of autistic young people who may have similar patterns of executive function strengths and challenges-like flexibility, planning, self-monitoring, and emotion regulation. Then, we investigated whether executive function subgroups were related to mental health problems in autistic youth. We found three different types of executive function subgroups in autistic youth, each with different patterns of mental health problems. This helps us identify specific profiles of executive function strengths and challenges that may be helpful with identifying personalized supports, services, and treatment strategies for mental health conditions.

3.
Cereb Cortex ; 33(11): 6633-6647, 2023 05 24.
Article in English | MEDLINE | ID: mdl-36721890

ABSTRACT

The common intersection of autism and transgender identities has been described in clinical and community contexts. This study investigates autism-related neurophenotypes among transgender youth. Forty-five transgender youth, evenly balanced across non-autistic, slightly subclinically autistic, and full-criteria autistic subgroupings, completed resting-state functional magnetic resonance imaging to examine functional connectivity. Results confirmed hypothesized default mode network (DMN) hub hyperconnectivity with visual and motor networks in autism, partially replicating previous studies comparing cisgender autistic and non-autistic adolescents. The slightly subclinically autistic group differed from both non-autistic and full-criteria autistic groups in DMN hub connectivity to ventral attention and sensorimotor networks, falling between non-autistic and full-criteria autistic groups. Autism traits showed a similar pattern to autism-related group analytics, and also related to hyperconnectivity between DMN hub and dorsal attention network. Internalizing, gender dysphoria, and gender minority-related stigma did not show connectivity differences. Connectivity differences within DMN followed previously reported patterns by designated sex at birth (i.e. female birth designation showing greater within-DMN connectivity). Overall, findings suggest behavioral diagnostics and autism traits in transgender youth correspond to observable differences in DMN hub connectivity. Further, this study reveals novel neurophenotypic characteristics associated with slightly subthreshold autism, highlighting the importance of research attention to this group.


Subject(s)
Autism Spectrum Disorder , Autistic Disorder , Transgender Persons , Infant, Newborn , Humans , Adolescent , Female , Brain/diagnostic imaging , Brain Mapping/methods , Autism Spectrum Disorder/diagnostic imaging , Magnetic Resonance Imaging/methods , Neural Pathways/diagnostic imaging
4.
Article in English | MEDLINE | ID: mdl-35868485

ABSTRACT

BACKGROUND: Covariation among psychiatric symptoms is being actively pursued for transdiagnostic dimensions of psychopathology with predictive utility. A superordinate dimension, the p factor, reflects overall psychopathology burden and has support from genetic and neuroimaging correlates. However, the neurocognitive correlates that link an elevated p factor to maladaptive outcomes are unknown. We tested the mediating potential of dynamic adjustments in cognitive control rooted in functional connections anchored by the dorsal anterior cingulate cortex (dACC) in a transdiagnostic pediatric sample. METHODS: A multiple mediation model tested the association between the p factor (derived by principal component analysis of Child Behavior Checklist syndrome scales) and outcome measured with the Vineland Adaptive Behavior Scale-II in 89 children ages 8 to 13 years (23 female) with a variety of primary neurodevelopmental diagnoses who underwent functional magnetic resonance imaging during a socioaffective Stroop-like task with eye gaze as distractor. Mediators included functional connectivity of frontoparietal- and salience network-affiliated dACC seeds during conflict adaptation. RESULTS: Higher p factor scores were related to worse adaptive functioning. This effect was partially mediated by conflict adaptation-dependent functional connectivity between the frontoparietal network-affiliated dACC seed and the right dorsolateral prefrontal cortex. Post hoc follow-up indicated that the p factor was related to all Vineland Adaptive Behaviors Scale-II domains; the association was strongest for socialization followed by daily living skills and then communication. Mediation results remained significant for socialization only. CONCLUSIONS: Higher psychopathology burden was associated with worse adaptive functioning in early adolescence. This association was mediated by weaker dACC-dorsolateral prefrontal cortex functional connectivity underlying modulation of cognitive control in response to contextual contingencies. Our results contribute to the identification of transdiagnostic and developmentally relevant neurocognitive endophenotypes of psychopathology.


Subject(s)
Gyrus Cinguli , Mental Disorders , Adolescent , Humans , Child , Female , Gyrus Cinguli/physiology , Magnetic Resonance Imaging , Neuroimaging , Cognition/physiology
5.
Curr Top Behav Neurosci ; 57: 159-177, 2022.
Article in English | MEDLINE | ID: mdl-35397063

ABSTRACT

High rates of co-occurring Attention-Deficit Hyperactivity Disorder (ADHD) and Autism Spectrum Disorders (ASD) suggest common causal pathways, which await elucidation. What is well-established, however, is the negative impact of comorbid ADHD and ASD on outcomes for everyday living, particularly in social interaction and communication and on broader psychopathology. Neurocognitive approaches suggest correlates of comorbidity are rooted in functional connectivity networks associated with executive control. There is support for familial origins, with molecular-genetic studies suggesting a causal role of pleiotropic genes. Further investigation is needed to elucidate fully how genetic risk for ADHD and ASD affects neurodevelopment and to identify structural and functional neural correlates and their behavioral sequelae. Identification of intermediate phenotypes is necessary to advance understanding, which requires studies that include the full spectrum of ASD and ADHD symptom severity, use longitudinal designs and multivariate methods to probe broad constructs, such as executive and social function, and consider other sources of heterogeneity, such as age, sex, and other psychopathology. Randomized efficacy trials targeting comorbid symptomatology are needed to mitigate negative developmental outcomes.


Subject(s)
Attention Deficit Disorder with Hyperactivity , Autism Spectrum Disorder , Attention Deficit Disorder with Hyperactivity/complications , Attention Deficit Disorder with Hyperactivity/epidemiology , Autism Spectrum Disorder/complications , Autism Spectrum Disorder/epidemiology , Comorbidity , Executive Function , Humans
6.
Neurology ; 98(3): e249-e259, 2022 01 18.
Article in English | MEDLINE | ID: mdl-34795045

ABSTRACT

BACKGROUND AND OBJECTIVES: Task fMRI is a clinical tool for language lateralization, but has limitations, and cannot provide information about network-level plasticity. Additional methods are needed to improve the precision of presurgical language mapping. We investigate language resting-state functional connectivity (RS fMRI; FC) in typically developing children (TD) and children with epilepsy. Our objectives were to (1) understand how FC components differ between TD children and those with epilepsy; (2) elucidate how the location of disease (frontal/temporal epilepsy foci) affects FC; and (3) investigate the relationship between age and FC. METHODS: Our sample included 55 TD children (mean age 12 years, range 7-18) and 31 patients with focal epilepsy (mean age 13 years, range 7-18). All participants underwent RS fMRI. Using a bilateral canonical language map as target, vertex-wise intrahemispheric FC map and interhemispheric FC map for each participant were computed and thresholded at top 10% to compute an FC laterality index (FCLI; [(L - R)/(L + R)]) of the frontal and temporal regions for both integration (intrahemispheric FC; FCLIi) and segregation (interhemispheric FC; FCLIs) maps. RESULTS: We found FC differences in the developing language network based on disease, seizure foci location, and age. Frontal and temporal FCLIi was different between groups (t[84] = 2.82, p < 0.01; t[84] = 4.68, p < 0.01, respectively). Frontal epilepsy foci had the largest differences from TD (Cohen d frontal FCLIi = 0.84, FCLIs = 0.51; temporal FCLIi = 1.29). Development and disease have opposing influences on the laterality of FC based on groups. In the frontal foci group, FCLIi decreased with age (r = -0.42), whereas in the temporal foci group, FCLIi increased with age (r = 0.40). Within the epilepsy group, increases in right frontal integration FCLI relates to increased right frontal task activation in our mostly left language dominant group (r = 0.52, p < 0.01). Language network connectivity is associated with higher verbal intelligence in children with epilepsy (r = 0.45, p < 0.05). DISCUSSION: These findings lend preliminary evidence that FC reflects network plasticity in the form of adaptation and compensation, or the ability to recruit support and reallocate resources within and outside of the traditional network to compensate for disease. FC expands on task-based fMRI and provides complementary and potentially useful information about the language network that is not captured using task-based fMRI alone.


Subject(s)
Brain Mapping , Language , Adolescent , Child , Functional Laterality/physiology , Humans , Magnetic Resonance Imaging , Temporal Lobe
7.
Article in English | MEDLINE | ID: mdl-34682531

ABSTRACT

The study of executive function decline in adults with Down syndrome (DS) is important, because it supports independent functioning in real-world settings. Inhibitory control is posited to be essential for self-regulation and adaptation to daily life activities. However, cognitive domains that most predict the capacity for inhibition in adults with DS have not been identified. The aim of this study was to identify cognitive domains that predict the capacity for inhibition, using novel data-driven techniques in a sample of adults with DS (n = 188; 49.47% men; 33.6 ± 8.8 years old), with low and moderate levels of intellectual disability. Neuropsychological tests, including assessment of memory, attention, language, executive functions, and praxis, were submitted to Random Forest, support vector machine, and logistic regression algorithms for the purpose of predicting inhibition capacity, assessed with the Cats-and-Dogs test. Convergent results from the three algorithms show that the best predictors for inhibition capacity were constructive praxis, verbal memory, immediate memory, planning, and written verbal comprehension. These results suggest the minimum set of neuropsychological assessments and potential intervention targets for individuals with DS and ID, which may optimize potential for independent living.


Subject(s)
Down Syndrome , Executive Function , Animals , Cats , Cognition , Dogs , Machine Learning , Memory, Short-Term , Neuropsychological Tests
8.
J Neurodev Disord ; 13(1): 35, 2021 09 15.
Article in English | MEDLINE | ID: mdl-34525948

ABSTRACT

BACKGROUND: Conceptual knowledge frameworks termed schemas facilitate memory formation and are posited to support flexible behavior. In adults, the medial temporal lobe (MTL) and medial prefrontal cortex (mPFC) trade-off in supporting schema-based memory formation, such that encoding of subsequently remembered schema-congruent information relies on mPFC, whereas schema-incongruent information relies on MTL. Whether this is true in the immature brain and relates to behavioral flexibility is unknown. In this preliminary investigation, we aimed to replicate the adult findings in typically developing (TD) children and to investigate the relevance to behavioral flexibility by examining a disorder with pathognomonic behavioral rigidity, autism spectrum disorder (ASD). METHODS: Children completed an associative subsequent memory paradigm, encoding object-scene pairs in an MRI scanner and subsequently completing a recognition test outside the scanner after a delay. Recognition performance was back sorted to construct remembered vs forgotten contrasts. One-way ANOVAS were conducted in MTL and mPFC masks for schema-congruency, followed by congruency by flexibility scores. Exploratory analyses were then conducted within the whole brain. RESULTS: As reported in adults, episodic memory was strongest for schema-congruent object-scene pairs, followed by intermediate pairs, and lowest for schema-incongruent pairs in both TD and ASD groups. However, the trade-off between mPFC and MTL in TD children differed from adult reports such that mPFC supported memory for intermediate schema-congruency and left anterior MTL supported memory for schema-congruent pairs. In ASD, mPFC engagement interacted with flexibility such that activation supporting memory for intermediate schema-congruency varied with parent-reported flexibility and was higher in those with more flexible behavior. A similar interaction was also observed in both the left dorsolateral and rostrolateral PFC in whole-brain analysis. CONCLUSION: Our findings provide the first preliminary evidence for the association of schema-based episodic memory formation and behavioral flexibility, an executive function impaired in multiple developmental disorders. Upon replication, this line of research holds promise for memory-based interventions addressing executive problems of behavioral rigidity.


Subject(s)
Autism Spectrum Disorder , Memory, Episodic , Adult , Child , Humans , Mental Recall , Prefrontal Cortex/diagnostic imaging , Recognition, Psychology
9.
Obesity (Silver Spring) ; 29(9): 1516-1525, 2021 09.
Article in English | MEDLINE | ID: mdl-34318605

ABSTRACT

OBJECTIVE: Neurocognitive differences in pediatric obesity may be underpinned by cortical structural alterations. Differences in cortical thickness associated with severe obesity were examined, and preliminary evidence was sought for changes following vertical sleeve gastrectomy (VSG). METHODS: A total of 18 adolescents with severe obesity (OB) and 17 without obesity (nOB), aged 14 to 21, underwent T1-weighted structural magnetic resonance imaging. A subset was scanned twice 5 months apart to compare cortical thickness following VSG (n = 6) with two control groups: wait-listed (n = 9) and nOB (n = 12). RESULTS: At baseline, OB had a thinner cortex than nOB in motor and superior parietal cortices. At follow-up, VSG adolescents lost weight, the wait-listed group gained weight, and nOB did not change. Group × Time interactions indicated that VSG had cortical thinning in orbitofrontal, primary sensorimotor, superior, and middle temporal cortices and thickening in lingual, fusiform, and lateral occipital cortices. Wait-listed and nOB groups largely did not change. CONCLUSIONS: Severe obesity is associated with a thinner cortex in motor and attentional function-associated regions. VSG resulted in cortical thinning in reward valuation, sensory, and perceptual regions and thickening in visual regions. Surgery-related changes in regions distinct from those associated with obesity suggest compensation, rather than normalization. These results provide preliminary evidence supporting structural neural alterations following sleeve gastrectomy.


Subject(s)
Obesity, Morbid , Pediatric Obesity , Adolescent , Child , Gastrectomy , Humans , Magnetic Resonance Imaging , Obesity, Morbid/diagnostic imaging , Obesity, Morbid/surgery , Pediatric Obesity/diagnostic imaging , Pediatric Obesity/surgery , Reward
10.
Neuroimage Clin ; 30: 102598, 2021.
Article in English | MEDLINE | ID: mdl-33858809

ABSTRACT

Development of a task-free method for presurgical mapping of language function is important for use in young or cognitively impaired patients. Resting state connectivity fMRI (RS-fMRI) is a task-free method that may be used to identify cognitive networks. We developed a voxelwise RS-fMRI metric, Functional Connectivity Hemispheric Contrast (FC-HC), to map the language network and determine language laterality through comparison of within-hemispheric language network connections (Integration) to cross-hemispheric connections (Segregation). For the first time, we demonstrated robustness and efficacy of a RS-fMRI metric to map language networks across five groups (total N = 243) that differed in MRI scanning parameters, fMRI scanning protocols, age, and development (typical vs pediatric epilepsy). The resting state FC-HC maps for the healthy pediatric and adult groups showed higher values in the left hemisphere, and had high agreement with standard task language fMRI; in contrast, the epilepsy patient group map was bilateral. FC-HC has strong but not perfect agreement with task fMRI and thus, may reflect related and complementary information about language plasticity and compensation.


Subject(s)
Epilepsy , Language , Adult , Brain Mapping , Child , Epilepsy/diagnostic imaging , Functional Laterality , Humans , Magnetic Resonance Imaging
11.
J Child Psychol Psychiatry ; 61(1): 51-61, 2020 01.
Article in English | MEDLINE | ID: mdl-31509248

ABSTRACT

BACKGROUND: Impairment of executive function (EF), the goal-directed regulation of thoughts, actions, and emotions, drives negative outcomes and is common across neurodevelopmental disorders including attention deficit hyperactivity disorder (ADHD) and autism spectrum disorder (ASD). A primary challenge to its amelioration is heterogeneity in symptom expression within and across disorders. Parsing this heterogeneity is necessary to attain diagnostic precision, a goal of the NIMH Research Domain Criteria Initiative. We aimed to identify transdiagnostic subtypes of EF that span the normal to impaired spectrum and establish their predictive and neurobiological validity. METHODS: Community detection was applied to clinical parent-report measures in 8-14-year-old children with and without ADHD and ASD from two independent cohorts (discovery N = 320; replication N = 692) to identify subgroups with distinct behavioral profiles. Support vector machine (SVM) classification was used to predict subgroup membership of unseen cases. Preliminary neurobiological validation was obtained with existing functional magnetic resonance imaging (fMRI) data on a subsample (N = 84) by testing hypotheses about sensitivity of EF subgroups versus DSM categories. RESULTS: We observed three transdiagnostic EF subtypes characterized by behavioral profiles that were defined by relative weakness in: (a) flexibility and emotion regulation; (b) inhibition; and (c) working memory, organization, and planning. The same tripartite structure was also present in the typically developing children. SVM trained on the discovery sample and tested on the replication sample classified subgroup membership with 77.0% accuracy. Split-half SVM classification on the combined sample (N = 1,012) yielded 88.9% accuracy (this SVM is available for public use). As hypothesized, frontal-parietal engagement was better distinguished by EF subtype than DSM diagnosis and the subgroup characterized with inflexibility failed to modulate right IPL activation in response to increased executive demands. CONCLUSIONS: The observed transdiagnostic subtypes refine current diagnostic nosology and augment clinical decision-making for personalizing treatment of executive dysfunction in children.


Subject(s)
Adolescent Development/physiology , Attention Deficit Disorder with Hyperactivity/physiopathology , Autism Spectrum Disorder/physiopathology , Child Development/physiology , Cognitive Dysfunction/classification , Cognitive Dysfunction/physiopathology , Emotional Regulation/physiology , Executive Function/physiology , Inhibition, Psychological , Memory, Short-Term/physiology , Adolescent , Attention Deficit Disorder with Hyperactivity/complications , Attention Deficit Disorder with Hyperactivity/diagnostic imaging , Autism Spectrum Disorder/complications , Autism Spectrum Disorder/diagnostic imaging , Child , Cognitive Dysfunction/diagnostic imaging , Cognitive Dysfunction/etiology , Cohort Studies , Emotional Regulation/classification , Executive Function/classification , Female , Functional Neuroimaging/standards , Humans , Individuality , Machine Learning , Magnetic Resonance Imaging , Male , Reproducibility of Results
12.
Dev Cogn Neurosci ; 40: 100727, 2019 12.
Article in English | MEDLINE | ID: mdl-31839215

ABSTRACT

Negative effects of obesity on memory and associated medial temporal circuitry have been noted in animal models, but the status in humans, particularly children, is not well established. Our study is the first to examine neural correlates of successful memory encoding of visual scenes and their associated context in adolescents with severe obesity (age 14-18 years, 43% male). Despite similar subsequent memory as adolescents without obesity (BMI for age and sex <95th percentile), those with severe obesity (BMI for age and sex 120% above the 95th percentile) showed reduced hippocampal, parahippocampal, frontal, and parietal engagement during encoding of remembered visual scenes and greater lateral temporal engagement during encoding of their associated context. Standardized testing revealed a trend level group difference in memory performance, with a larger magnitude of obesity-related difference in recollection-related memory that was mediated by individual differences in lateral temporal activation during contextual encoding. The observed widespread functional alterations are concerning in light of the importance of mnemonic processing for academic achievement and feeding behavior and underscore the need for prevention and intervention initiatives for pediatric obesity.


Subject(s)
Magnetic Resonance Imaging/methods , Memory, Episodic , Obesity, Morbid/complications , Adolescent , Female , Humans , Male
13.
Psychiatry Res Neuroimaging ; 285: 1-8, 2019 03 30.
Article in English | MEDLINE | ID: mdl-30711709

ABSTRACT

The serotonin transporter (5-HTTLPR) and brain-derived neurotrophic factor (BDNF) gene polymorphisms have been associated with risk for affective disorders and functional variability of the amygdala. We examined whether the two genotypes interactively influence intrinsic functional connectivity (FC) of the amygdala and whether FC mediates the genetic association with anxiety. Eighty genotyped healthy adults underwent resting state fMRI and completed the self-reported State-Trait Anxiety Inventory. Interactive genetic association with anxiety was observed such that effects of 5-HTTLPR depended on the BDNF Val66Met polymorphism (rs6265 variant), with higher anxiety scores in short and Met carriers compared to the other allelic groups. Voxel-wise FC with left and right amygdala seeds identified regions that were sensitive to variability in anxiety scores. A significant moderated mediation model demonstrated that the effect of 5-HTTLPR genotype on anxiety, moderated by BDNF Val66Met genotype, was fully mediated by FC between the left amygdala and the right dorsolateral prefrontal cortex, a cognitive control-related region, during a task-free state. FC was highest in carriers of the 5-HTTLPR short allele and BDNF Met allele. These findings establish intrinsic amygdala-prefrontal functional connectivity as a potential intermediate phenotype for anxiety, an important step toward identification of causal pathways for vulnerability to affective disorders.


Subject(s)
Amygdala/diagnostic imaging , Anxiety/diagnostic imaging , Anxiety/genetics , Brain-Derived Neurotrophic Factor/genetics , Nerve Net/diagnostic imaging , Serotonin Plasma Membrane Transport Proteins/genetics , Adolescent , Amygdala/physiology , Epistasis, Genetic/physiology , Female , Humans , Magnetic Resonance Imaging/methods , Male , Nerve Net/physiology , Polymorphism, Genetic/genetics , Prefrontal Cortex/diagnostic imaging , Prefrontal Cortex/physiology , Young Adult
14.
Neuroimage ; 184: 171-179, 2019 01 01.
Article in English | MEDLINE | ID: mdl-30217544

ABSTRACT

Functional near-infrared spectroscopy (fNIRS) is an optical neuroimaging technique of growing interest as a tool for investigation of cortical activity. Due to the on-head placement of optodes, artifacts arising from head motion are relatively less severe than for functional magnetic resonance imaging (fMRI). However, it is still necessary to remove motion artifacts. We present a novel motion correction procedure based on robust regression, which effectively removes baseline shift and spike artifacts without the need for any user-supplied parameters. Our simulations show that this method yields better activation detection performance than 5 other current motion correction methods. In our empirical validation on a working memory task in a sample of children 7-15 years, our method produced stronger and more extensive activation than any of the other methods tested. The new motion correction method enhances the viability of fNIRS as a functional neuroimaging modality for use in populations not amenable to fMRI.


Subject(s)
Brain Mapping/methods , Image Enhancement/methods , Spectroscopy, Near-Infrared , Algorithms , Artifacts , Computer Simulation , Humans , ROC Curve , Reproducibility of Results , Signal Processing, Computer-Assisted
15.
Cereb Cortex ; 29(9): 3912-3921, 2019 08 14.
Article in English | MEDLINE | ID: mdl-30364937

ABSTRACT

Noninvasive brain stimulation (NIBS) is a promising treatment for psychiatric and neurologic conditions, but outcomes are variable across treated individuals. In principle, precise targeting of individual-specific features of functional brain networks could improve the efficacy of NIBS interventions. Network theory predicts that the role of a node in a network can be inferred from its connections; as such, we hypothesized that targeting individual-specific "hub" brain areas with NIBS should impact cognition more than nonhub brain areas. Here, we first demonstrate that the spatial positioning of hubs is variable across individuals but reproducible within individuals upon repeated imaging. We then tested our hypothesis in healthy individuals using a prospective, within-subject, double-blind design. Inhibition of a hub with continuous theta burst stimulation disrupted information processing during working-memory more than inhibition of a nonhub area, despite targets being separated by only a few centimeters on the right middle frontal gyrus of each subject. Based upon these findings, we conclude that individual-specific brain network features are functionally relevant and could leveraged as stimulation sites in future NIBS interventions.


Subject(s)
Cerebral Cortex/anatomy & histology , Cerebral Cortex/physiology , Memory, Short-Term/physiology , Neural Inhibition/physiology , Transcranial Direct Current Stimulation , Adult , Double-Blind Method , Female , Humans , Male , Neural Pathways/anatomy & histology , Neural Pathways/physiology , Prospective Studies , Reproducibility of Results , Young Adult
16.
Autism Res ; 12(2): 200-211, 2019 02.
Article in English | MEDLINE | ID: mdl-30556326

ABSTRACT

Amygdala dysfunction has been implicated in numerous neurodevelopmental disorders, including autism spectrum disorder (ASD). Previous studies in mice and humans, respectively, have linked Pac1r/PAC1R function to social behavior and PTSD-susceptibility. Based on this connection to social and emotional processing and the central role played by the amygdala in ASD, we examined a putative role for PAC1R in social deficits in ASD and determined the pattern of gene expression in the developing mouse and human amygdala. We reveal that Pac1r/PAC1R is expressed in both mouse and human amygdala from mid-neurogenesis through early postnatal stages, critical time points when altered brain trajectories are hypothesized to unfold in ASD. We further find that parents of autistic children carrying a previously identified PTSD-risk genotype (CC) report greater reciprocal social deficits compared to those carrying the non-risk GC genotype. Additionally, by exploring resting-state functional connectivity differences in a subsample of the larger behavioral sample, we find higher functional connectivity between the amygdala and right middle temporal gyrus in individuals with the CC risk genotype. Thus, using multimodal approaches, our data reveal that the amygdala-expressed PAC1R gene may be linked to severity of ASD social phenotype and possible alterations in brain connectivity, therefore potentially acting as a modifier of amygdala-related phenotypes. Autism Res 2019, 12: 200-211 © 2018 International Society for Autism Research, Wiley Periodicals, Inc. LAY SUMMARY: In this multimodal study across mouse and human, we examined expression patterns of Pac1r/PAC1R, a gene implicated in social behavior, and further explored whether a previously identified human PTSD-linked mutation in PAC1R can predict brain connectivity and social deficits in ASD. We find that PAC1R is highly expressed in the both the mouse and human amygdala. Furthermore, our human data suggest that PAC1R genotype is linked to severity of social deficits and functional amygdala connectivity in ASD.


Subject(s)
Autism Spectrum Disorder/genetics , Brain/diagnostic imaging , Genotype , Magnetic Resonance Imaging/methods , Phenotype , Receptors, Pituitary Adenylate Cyclase-Activating Polypeptide/genetics , Adolescent , Animals , Autism Spectrum Disorder/physiopathology , Brain/physiopathology , Brain Mapping/methods , Child , Disease Models, Animal , Female , Humans , Male , Mice , Mice, Inbred C57BL
17.
Article in English | MEDLINE | ID: mdl-29944414

ABSTRACT

Memory impairment in schizophrenia has been linked to abnormal functioning of fronto-temporal networks. In this pilot study, we investigated whether 12-weeks of exercise improved hippocampal-dependent memory functions and resting-state functional connectivity in middle-aged adults with schizophrenia. The exercise regimen was feasible, well-attended, and safe. There was a pre- to post-intervention increase in spatial memory accuracy that was correlated to an increase in hippocampal-prefrontal cortex connectivity. No increase was found in pattern separation performance or hippocampal volume. A controlled trial is needed to replicate these findings and elucidate the functional brain networks underlying exercise-induced cognitive improvement in schizophrenia.

18.
Child Obes ; 14(5): 265-279, 2018 07.
Article in English | MEDLINE | ID: mdl-29874102

ABSTRACT

OBJECTIVE: This study examined the effect of pediatric obesity on executive function and reward-related decision-making, cognitive processes that are relevant to obesogenic behaviors, and evaluated their association with sample (e.g., age, gender, intelligence, and socioeconomic status, SES) and study/task (e.g., categorical/continuous variable, food stimuli) characteristics. METHODS: A random-effects meta-analysis was conducted using Hedge's g effect sizes of published studies from 1960 to 2016, limited to children younger than the age of 21 years without medical comorbidities. Analysis included estimation of heterogeneity (τ2), publication bias (funnel-plot symmetry and fail-safe N), and sensitivity analyses for sample and study/task characteristics. RESULTS: Across 68 studies with 70 samples, obesity was associated with worse functioning overall (-0.24; 95CI: -0.30 to -0.19; p < 0.001) and for each component process (attention, switching, inhibition, interference, working memory, reward, delay of gratification: -0.19 to -0.38; p's < 0.017), except trait impulsivity (-0.06; 95CI: -0.18 to 0.07). Deficits increased with age and female composition of the sample for inhibition (p = 0.002). No other characteristics moderated effect of obesity. CONCLUSIONS: Small-to-moderate negative associations with obesity were observed for executive and reward-related performance, but not on reported impulsivity in studies with children younger than the age of 21 years. These results were not moderated by IQ, SES, and study/task characteristics. Age and gender moderated association with inhibition, with a larger obesity-related deficit in older and predominantly female samples. These results suggest cognitive and demographic intervention targets for prevention and mitigation of obesogenic behavior.


Subject(s)
Executive Function/physiology , Pediatric Obesity , Reward , Adolescent , Adult , Attention/physiology , Child , Child, Preschool , Female , Humans , Male , Pediatric Obesity/epidemiology , Pediatric Obesity/psychology , Young Adult
19.
J Pediatr Psychol ; 43(8): 916-927, 2018 09 01.
Article in English | MEDLINE | ID: mdl-29788390

ABSTRACT

Objectives: Evidence in adults suggests that improvements in cognitive performance may follow weight loss resulting from bariatric surgery, and baseline cognitive performance may be associated with weight loss following surgery. This has not been evaluated in adolescents. Method: Participants were 38 adolescents of age 14-21 years composed of three groups: (1) 12 adolescents with severe obesity who received vertical sleeve gastrectomy during the study (VSG); (2) 14 adolescents with severe obesity who were wait-listed for VSG (WL); and (3) 12 healthy weight controls (HC). Participants completed testing of visual memory, verbal memory, and executive functioning at baseline (T1), which occurred presurgery for the VSG group, and approximately 4 months after baseline (T2). Body mass index (BMI) was assessed at T1, T2, and additionally at 6 months following VSG for the adolescents who received surgery. Results: Although there was evidence of greater improvement for the VSG as compared with WL and HC groups in visual and verbal memory, group differences did not reach significance and effect sizes were small (η2 < 0.01). There was a significant positive association between indices of baseline executive functioning and excess BMI loss at 6 months postsurgery. Conclusions: This small pilot study showed no significant differences by group in cognitive performance post-VSG. There was a significant association of baseline cognitive performance with weight loss outcomes. Given the very preliminary nature of these results in a small sample, future research should examine these relationships in a larger sample and evaluate mechanisms of these associations (e.g., insulin resistance, sleep, physical activity).


Subject(s)
Bariatric Surgery , Cognition/physiology , Obesity, Morbid/surgery , Adolescent , Adult , Body Mass Index , Female , Humans , Male , Obesity, Morbid/psychology , Pilot Projects , Postoperative Period , Treatment Outcome , Weight Loss , Young Adult
20.
Child Obes ; 14(3): 189-196, 2018 04.
Article in English | MEDLINE | ID: mdl-29394100

ABSTRACT

OBJECTIVE: Executive and motivational dysfunction have been associated with pediatric obesity. Poor sleep quality and psychopathology, often comorbid with obesity, are also associated with executive and motivational dysfunction. We examined the contribution of these comorbid factors to the association between obesity and executive function and reward-related decision-making. METHODS: Seven- to 18-year-old children with and without obesity performed a working memory task with low and high loads, a response inhibition task, and a probabilistic reward-related decision-making task. Parents filled out standardized measures of executive function in everyday behavior, sleep health, and psychiatric symptoms. Analyses controlled for age, gender, IQ, and parental education. RESULTS: Children with obesity showed worse working memory performance under higher load (p = 0.007), and worse parent-reported behavioral regulation (p = 0.05) and metacognition (p = 0.04) in everyday behavior and their reward-related decision-making was less consistent with learned probabilistic conditions (p = 0.04). Response inhibition did not differ between groups. Children with obesity had worse parent-reported sleep health (p < 0.01) and 4.27 greater odds of clinically relevant internalizing symptomology (p = 0.03), both of which mediated the effect of obesity on behavioral regulation (p's < 0.01) and metacognition (p's < 0.01). Performance-based assessments were not associated with sleep health or psychopathology. CONCLUSIONS: Sleep quality and internalizing psychopathology were worse in children with obesity and contributed to parent-reported executive dysfunction in their everyday behavior. Performance-based measures of working memory and decision-making were not associated with those comorbidities of obesity.


Subject(s)
Executive Function/physiology , Mental Disorders/physiopathology , Pediatric Obesity/psychology , Sleep/physiology , Adolescent , Child , Child Behavior/physiology , Decision Making/physiology , Female , Humans , Male , Memory/physiology , Mental Disorders/complications , Motivation , Parents , Pediatric Obesity/complications , Pediatric Obesity/physiopathology , Reward , Surveys and Questionnaires
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