Functional Brain Systems Research Articles

Miswiring the brain: Human prenatal Δ9-tetrahydrocannabinol use associated with altered fetal hippocampal brain network connectivity

Increasing evidence supports a link between maternal prenatal cannabis use and altered neural and physiological development of the child. However, whether cannabis use relates to altered human brain development prior to birth, and specifically, whether maternal prenatal cannabis use relates to connectivity of fetal functional brain systems, remains an open question. The major objective of this study was to identify whether maternal prenatal cannabis exposure (PCE) is associated with variation in human brain hippocampal functional connectivity prior to birth. Prenatal drug toxicology and fetal fMRI data were available in a sample of 115 fetuses [43 % female; mean age 32.2 weeks (SD = 4.3)]. Voxelwise hippocampal connectivity analysis in a subset of age and sex-matched fetuses revealed that PCE was associated with alterations in fetal dorsolateral, medial and superior frontal, insula, anterior temporal, and posterior cingulate connectivity. Classification of group differences by age 5 outcomes suggest that compared to the non-PCE group, the PCE group is more likely to have increased connectivity to regions associated with less favorable outcomes and to have decreased connectivity to regions associated with more favorable outcomes. This is preliminary evidence that altered fetal neural connectome may contribute to neurobehavioral vulnerability observed in children exposed to cannabis in utero.

Global efficiency of the motor network is decreased in Parkinson's disease in comparison with essential tremor and healthy controls.

BackgroundGraph theory (GT) is a mathematical field that analyses complex networks that can be applied to neuroimaging to quantify brain's functional systems in Parkinson's disease (PD) and essential tremor (ET).ObjectivesTo evaluate the functional connectivity (FC) measured by the global efficiency (GE) of the motor network in PD and compare it to ET and healthy controls (HC), and correlate it to clinical parameters.Methods103 subjects (54PD, 18ET, 31HC) were submitted to structural and functional MRI. A network was designed with regions of interest (ROIs) involved in motor function, and GT was applied to determine its GE. Clinical parameters were analyzed as covariates to estimate the impact of disease severity and medication on GE.ResultsGE of the motor circuit was reduced in PD in comparison with HC (p .042). Areas that most contributed to it were left supplementary motor area (SMA) and bilateral postcentral gyrus. Tremor scores correlated positively with GE of the motor network in PD subgroups. For ET, there was an increase in the connectivity of the anterior cerebellar network to the other ROIs of the motor circuit in comparison with PD.ConclusionsFC measured by the GE of the motor network is diminished in PD in comparison with HC, especially due to decreased connectivity of left SMA and bilateral postcentral gyrus. This finding supports the theory that there is a global impairment of the motor network in PD, and it does not affect just the basal ganglia, but also areas associated with movement modulation. The ET group presented an increased connectivity of the anterior cerebellar network to the other ROIs of the motor circuit when compared to PD, which reinforces what it is known about its role in this pathology.

The feasibility of an in-scanner smoking lapse paradigm to examine the neural correlates of lapses.

Quitting smoking is notoriously difficult. Models of nicotine dependence posit that strength of cognitive control contributes to maintaining smoking abstinence during smoking cessation attempts. We examine the role for large-scale functional brain systems associated with cognitive control in smoking lapse using a novel adaption of a well-validated behavioral paradigm. We use data from 17 daily smokers (five females) after 12h of smoking abstinence. Participants completed up to 10 sequential 5-min functional magnetic resonance imaging (fMRI) runs, within a single scanning session. After each run, participants decided whether to stay in the scanner in order to earn additional money or to terminate the session in order to smoke a cigarette (i.e., lapse) and forego additional monetary reward. Cox regression results indicate that decreased segregation of the default mode system from the frontoparietal system undermines the ability to resist smoking. This study demonstrates the feasibility of modifying an established behavioral model of smoking lapse behavior for use in the neuro imaging environment, and it provides initial evidence that this approach yields valuable information regarding fine-grained, time-varying changes in patterns of neural activity in the moments leading up to a decision to smoke. Specifically, results lend support to the hypothesis that the time-varying interplay between large-scale functional brain systems associated with cognitive control is implicated in smoking lapse behavior.

Relationships Between Music and Empathic Decision Making in Healthy Young Adults

Music and empathy are components of social experience. Similar and adjacent functional brain systems are required in the production and understanding of music, the processing of emotion, and engagement in social behavior. Activity in these brain systems is often reflected in autonomic features, including dynamic behavior of the parasympathetic and sympathetic nervous systems. Music may influence prosocial behavior and this effect may be reflected by the behavior of the autonomic nervous system. This experiment was designed to evaluate these relationships. Healthy undergraduate students ( N = 60) participated in Cyberball, a task sensitive to differences in prosocial behavior, while listening to or not listening to different types of music. Results indicated that music positively affects prosocial behavior, but autonomic activity does not reflect the degree of music’s effect on prosocial behavior.

Pre-reading language abilities and the brain’s functional reading network in young children

Early childhood is an important period for language development that lays the foundation for future reading abilities. However, little research has focused on the functional brain systems supporting pre-reading language abilities in typically developing children. Here, we investigated functional connectivity using passive viewing functional magnetic resonance imaging (fMRI) in 50 healthy children aged 2.85–5.07 years (3.84 ​± ​0.60 years, 22 female/28 male). Children completed the NEPSY-II Phonological Processing and Speeded Naming subtests and underwent fMRI while watching a movie of their choice. Functional connectivity was measured between key brain reading areas (bilateral angular gyrus, superior temporal gyrus, and inferior frontal gyrus) and the rest of the brain. Age-adjusted pre-reading scores positively correlated with functional connectivity between (1) the right angular gyrus and superior temporal gyrus, (2) the bilateral angular gyri and right pars triangularis and motor areas, (3) the left superior temporal gyrus and bilateral medial frontal gyrus and right cerebellum, (4) the left pars triangularis and middle occipital gyrus and insula, and (5) the right pars triangularis and the bilateral thalamus. Higher pre-reading scores were associated with stronger negative functional connectivity between (1) the left angular gyrus and auditory cortex, (2) the left superior temporal gyrus and occipital vision areas, (3) the right pars triangularis and medial frontal region, and (4) the right superior temporal gyrus and the posterior cingulate/precuneus. These results suggest better integration of the reading network, as well as its connections with other brain areas that support language or reading, and more dissociation between reading areas and the default mode network, in young children with better pre-reading skills. Our findings show that relationships between functional connectivity and pre-reading language skills are evident in young children even before formal reading instruction.

Medial temporal lobe connectivity and its associations with cognition in early Alzheimer's disease.

Human episodic memory critically depends on subregions of the medial temporal lobe, which are part of functional brain systems such as the anterior-temporal and the posterior-medial system. Here we analysed how Alzheimer's pathology affects functional connectivity within these systems. Data from 256 amyloid-β-negative cognitively unimpaired, 103 amyloid-β-positive cognitively unimpaired, and 83 amyloid-β-positive individuals with mild cognitive impairment were analysed. Amyloid-β and tau pathology were measured using the CSF amyloid-β42/40 ratio and phosphorylated tau, respectively. We found that amyloid-β-positive cognitively unimpaired individuals were mainly characterized by decreased functional connectivity between the medial temporal lobe and regions in the anterior-temporal system, most prominently between left perirhinal/entorhinal cortices and medial prefrontal cortex. Furthermore, correlation analysis in this group revealed decreasing functional connectivity between bilateral perirhinal/entorhinal cortices, anterior hippocampus and posterior-medial regions with increasing levels of phosphorylated tau. The amyloid-β-positive individuals with mild cognitive impairment mostly exhibited reduced connectivity between the medial temporal lobe and posterior-medial regions, predominantly between the anterior hippocampus and posterior cingulate cortex. In addition, they showed hyperconnectivity within the medial temporal lobe and its immediate proximity. Lower medial temporal-cortical functional connectivity networks resulting from the group comparisons of cognitively unimpaired individuals were associated with reduced memory performance and more rapid longitudinal memory decline as shown by linear mixed-effects regression analysis. Finally, we found that reduced medial temporal-cortical connectivity in mildly cognitively impaired individuals was related to reduced entorhinal thickness and white matter integrity of the parahippocampal cingulum and the fornix. No such relationships were found in cognitively unimpaired individuals. In conclusion, our findings show that the earliest changes in preclinical Alzheimer's disease might involve decreased connectivity within the anterior-temporal system, and early changes in connectivity might be related to memory impairment, but not to structural changes. With disease progression and increased tau pathology, medial temporal functional connectivity with posterior-medial regions seems to be increasingly impaired. In individuals with mild cognitive impairment, reduced functional connectivity is associated with structural brain changes as well as the emergence of locally increased connectivity patterns. Thus, functional connectivity between the medial temporal lobe and the anterior-temporal and posterior-medial system could serve as stage-specific functional markers in early Alzheimer's disease.

ЗАДАЧНЫЙ ПОДХОД В ИСКУССТВЕННОМ ИНТЕЛЛЕКТЕ

The paper considers the task approach to artificial intelligence. It is shown that, on the one hand, it generalizes such approaches as the agent-based approach and general artificial intelligence, and, on the other hand, accurately reflects the cognitive processes and purposeful behavior described in the physiological theory of functional brain systems.

Increased RTV in ADHD: A Novel Approach to Detect Inattention [Florida International University

Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder and the second most common mental condition in U.S. children, affecting more than 6.1 million individuals between the ages of 2-17 years. Defined by two behavioral features - inattention and hyperactivity - identifying and studying ADHD, especially related periods of inattention, a defining feature, poses an important limitation. Recent studies have identified elevated reaction time variability (RTV) as a reliable feature of ADHD, that may be related to periods of inattention. However, the neural mechanisms behind RTV, and thereby inattention, are not well understood. The default mode network (DMN) is a functional brain system responsible for internally-directed mental processes, that is active when not engaged in cognitively demanding externally directed tasks. Activation of the DMN during active states, thus, could disrupt externally directed behavior and related neurobiological mechanisms – perhaps acting as an internal distraction. We predicted that activation in the DMN during an externally directed task will be elevated during periods of increased RTV. Further, we anticipated DMN activation to precede abnormally slow responses. We used blood-oxygen level dependent (BOLD) functional magnetic resonance imaging (fMRI) while participants with and without ADHD performed a standard sustained attention to response (SART) task. We then examined the activation of the DMN during episodes of aberrant RTV, defined as reaction times more than two standard deviations from the preceding measure of variability, to ascertain the nature of the aforementioned association. The neurobiological mechanisms that are related to the attention-deficit in ADHD must be better understood to aid in diagnosis and treatment. This study aims to be the first to provide comprehensive evidence of the neural underpinnings behind increased RTV and thereby inattention in individuals with ADHD. The current system to diagnose ADHD in children is based on potentially subjective behavioral observations by parents and teachers. Identifying increased RTV as a behavioral marker of ADHD with a well-characterized neurobiological mechanism may enable a more effective and objective method of diagnosis, resulting in more successful treatment outcomes and decreased costs of care for families of children with the disorder.

Whole-brain functional connectivity during script-driven aggression in borderline personality disorder

ObjectiveIntense anger and anger-related aggression are frequently reported by patients with borderline personality disorders (BPD). Recent results suggest that anger-related aggression and its control is associated with a complex interplay of different neural systems in BPD. To further investigate this, we complement standard activation and seed-based connectivity analyses by examining whole-brain changes in functional connectivity during anger and reactive aggression in BPD. MethodsWe reanalyzed functional MRI data from 33 women with BPD, all of them fulfilling BPD criterion 8, “anger proneness”, according to DSM-IV, and 30 healthy women. Subjects performed a script-driven imagery task consisting of four phases: baseline, anger-induction by a narrative of interpersonal rejection, a narrative of directing physical aggression towards others, and relaxation. We used a data-driven, spatially constrained spectral clustering approach to parcellate the brain into 200 regions. For each script-phase and subject, we computed the full connectivity matrix using wavelet coefficient correlations in the 0.05–0.10 Hz range. We calculated the individual increase in connectivity from baseline to the anger-induction and physical aggression phases by subtracting the corresponding connectivity matrices per subject, as well as the increase and decrease from the anger-induction to the aggression phase. We then applied permutation-based sampling to determine a combined threshold on the strength of individual connections and the size of the discovered networks for these difference matrices. ResultsWe discovered a single, large network showing a significantly stronger increase in connectivity from baseline to the aggression phase in female patients with BPD compared to healthy women. This network consisted of regions in the anterior and posterior cingulate cortex, precuneus, dorsomedial prefrontal cortex, superior and middle temporal gyrus, hippocampus, insula, ventrolateral and dorsolateral prefrontal cortex, superior parietal lobe, thalamus, precentral and postcentral gyrus, caudate, pallidum, cerebellum, middle occipital lobe, lingual gyrus, calcarine sulcus, and fusiform gyrus. Hub regions with highest node centrality were found in the right caudate and left thalamus. We found no significant differences for the increase of connectivity from baseline to anger-induction, as well as for the increase or decrease from the anger-induction to the aggression phase. ConclusionsWe identified a large network showing a significantly stronger increase in connectivity from baseline to the aggression phase in female patients with BPD compared to healthy women. The regions constituting this network belong to four previously described functional networks: The frontoparietal cognitive control network, the extended default mode network, the visual system, and the motor system. This stronger increase in connectivity between regions of different functional brain systems associated with cognitive control of behavior, socio-affective and self-referential thinking, as well as salience processing and emotion regulation, visual perception, and action is mediated via hubs in the thalamus and caudate, i.e., core components of the thalamocorticostriatal motor loop essential for action selection and initiation. These findings suggest increased interaction of prefrontal cognitive control processes with thalamocorticostriatal action-selection processes in female patients with BPD during the processing of aggressive action impulses, which are facilitated by states of high emotional salience and associated processes of self-referential and social processing, and ineffective emotion regulation.

Sex differences in functional connectivity during fetal brain development

Sex-related differences in brain and behavior are apparent across the life course, but the exact set of processes that guide their emergence in utero remains a topic of vigorous scientific inquiry. Here, we evaluate sex and gestational age (GA)-related change in functional connectivity (FC) within and between brain wide networks. Using resting-state functional magnetic resonance imaging we examined FC in 118 human fetuses between 25.9 and 39.6 weeks GA (70 male; 48 female). Infomap was applied to the functional connectome to identify discrete prenatal brain networks in utero. A consensus procedure produced an optimal model comprised of 16 distinct fetal neural networks distributed throughout the cortex and subcortical regions. We used enrichment analysis to assess network-level clustering of strong FC-GA correlations separately in each sex group, and to identify network pairs exhibiting distinct patterns of GA-related change in FC between males and females. We discovered both within and between network FC-GA associations that varied with sex. Specifically, associations between GA and posterior cingulate-temporal pole and fronto-cerebellar FC were observed in females only, whereas the association between GA and increased intracerebellar FC was stronger in males. These observations confirm that sexual dimorphism in functional brain systems emerges during human gestation.

The Transitions Between Dynamic Micro-States Reveal Age-Related Functional Network Reorganization.

Normal dynamic change in human brain occurs with age increasing, yet much remains unknown regarding how brain develops, matures, and ages. Functional connectivity analysis of the resting-state brain is a powerful method for revealing the intrinsic features of functional networks, and micro-states, which are the intrinsic patterns of functional connectivity in dynamic network courses, and are suggested to be more informative of brain functional changes. The aim of this study is to explore the age-related changes in these micro-states of dynamic functional network. Three healthy groups were included: the young (ages 21–32 years), the adult (age 41–54 years), and the old (age 60–86 years). Sliding window correlation method was used to construct the dynamic connectivity networks, and then the micro-states were individually identified with clustering analysis. The distribution of age-related connectivity variations in several intrinsic networks for each micro-state was analyzed then. The micro-states showed substantial age-related changes in the transitions between states but not in the dwelling time. Also there was no age-related reorganization observed within any micro-state. But there were reorganizations observed in the transition between them. These results suggested that the identified micro-states represented certain underlying connectivity patterns in functional brain system, which are similar to the intrinsic cognitive networks or resources. In addition, the dynamic transitions between these states were probable mechanisms of reorganization or compensation in functional brain networks with age increasing.

Luria’s Syndrome for Neuropsychological Rehabilitation of Adolescents

Neuropsychology, as a science, studies possible relations between psychological processes and brain in cases of normality and diverse pathologies. Such kind of relations might be established and understood by different manners. A.R. Luria proposed unique and particular way of approach by brain units. Such conceptionis not completely understood and even less used in practice of diagnosis and rehabilitation today. Neuropsychologists provide assessments of isolated functions by help of psychometric procedures. The judgment of diagnosis refers to such terms as “attention or memory disorders”, dyslexia and so on. All these terms are really far away from the conception of systemic and dynamic representation of human actions infunctional brain systems. Same or worse is the situation with rehabilitation directed to isolated operations as conductive exercises for isolated functions. The objective of our report is to share opinion of application of Luria’s methodology of syndrome analysis. Procedures of systemic functional diagnosis must conduct to systemic procedures in rehabilitation. An example of qualitative assessment of adolescent patient withbrain injury is presented. Goals, stages and examples of formation of actions in rehabilitation with results are provided. Psychological conceptions of stage by stage formation and orientation base of action and its usage for rehabilitation is taken into account. We conclude that systemic and dynamic approach in neuropsychology might be conducted in reality of assessment and rehabilitation. We discuss the necessity of establishment of bridges between psychological theory of actions instead of functions and systemic representation of actions by functional brain systems.
 Keywords: neuropsychological rehabilitation, concepts of neuropsychology, functional diagnosis, qualitative neuropsychology, brain injury rehabilitation.

Restricted and Repetitive Behavior and Brain Functional Connectivity in Infants at Risk for Developing Autism Spectrum Disorder

BackgroundRestricted and repetitive behaviors (RRBs), detectable by 12 months in many infants in whom autism spectrum disorder (ASD) is later diagnosed, may represent some of the earliest behavioral markers of ASD. However, brain function underlying the emergence of these key behaviors remains unknown. MethodsBehavioral and resting-state functional connectivity (fc) magnetic resonance imaging data were collected from 167 children at high and low familial risk for ASD at 12 and 24 months (n = 38 at both time points). Twenty infants met criteria for ASD at 24 months. We divided RRBs into four subcategories (restricted, stereotyped, ritualistic/sameness, self-injurious) and used a data-driven approach to identify functional brain networks associated with the development of each RRB subcategory. ResultsHigher scores for ritualistic/sameness behavior were associated with less positive fc between visual and control networks at 12 and 24 months. Ritualistic/sameness and stereotyped behaviors were associated with less positive fc between visual and default mode networks at 12 months. At 24 months, stereotyped and restricted behaviors were associated with more positive fc between default mode and control networks. Additionally, at 24 months, stereotyped behavior was associated with more positive fc between dorsal attention and subcortical networks, whereas restricted behavior was associated with more positive fc between default mode and dorsal attention networks. No significant network-level associations were observed for self-injurious behavior. ConclusionsThese observations mark the earliest known description of functional brain systems underlying RRBs, reinforce the construct validity of RRB subcategories in infants, and implicate specific neural substrates for future interventions targeting RRBs.

Altered functional network connectivity relates to motor development in children born very preterm

Individuals born very preterm (<32 weeks gestation) are at increased risk for neuromotor impairments. The ability to characterize the structural and functional mechanisms underlying these impairments remains limited using existing neuroimaging techniques. Resting state-functional magnetic resonance imaging (rs-fMRI) holds promise for defining the functional network architecture of the developing brain in relation to typical and aberrant neurodevelopment. In 58 very preterm and 65 term-born children studied from birth to age 12 years, we examined relations between functional connectivity measures from low-motion rs-fMRI data and motor skills assessed using the Movement Assessment Battery for Children, 2nd edition. Across all subscales, motor performance was better in term than very preterm children. Examination of relations between functional connectivity and motor measures using enrichment analysis revealed between-group differences within cerebellar, frontoparietal, and default mode networks, and between basal ganglia-motor, thalamus-motor, basal ganglia-auditory, and dorsal attention-default mode networks. Specifically, very preterm children exhibited weaker associations between motor scores and thalamus-motor and basal ganglia-motor network connectivity. These findings highlight key functional brain systems underlying motor development. They also demonstrate persisting developmental effects of preterm birth on functional connectivity and motor performance in childhood, providing evidence for an alternative network architecture supporting motor function in preterm children.

Assessment of Behavioral Approach and Behavioral Inhibition Systems in Mood Disorders.

Introduction:Psychiatric disorders could be evaluated in terms of behavioral activation and inhibition systems. Dysregulation of these systems may lead to development of manic or depressive episodes in patients with mood disorders. This study aimed to identify Behavioral Approach System (BAS) and Behavioral Inhibition System (BIS) hypersensitivity as the functional brain system behaviors in patients with major depressive disorder and bipolar mood disorder I, compared to healthy individuals.Methods:This case-control study was conducted in Razi Psychiatric Hospital, a mental health referral center in Northwest of Iran. The study consisted of two groups of patients, one with major depressive and the other with bipolar mood disorders and one healthy group. Each group had 40 patients (20 men and 20 women). The study data were collected through BIS and BAS questionnaire, Beck Depression Inventory (BDI-II), Young Mania Rating Scale (YMRS). The obtained data were analyzed by SPSS version 18.Results:The findings showed a significant negative correlation between BIS, BAS and BAS subscales with the severity of depression and positive correlation with mania symptoms (P<0.05).Conclusion:BAS and BIS dysregulations may predispose people to mood disorder symptoms. BAS is hyperactive during manic phase and may predict the symptom severity of bipolar mood disorder.

Subtyping cognitive profiles in Autism Spectrum Disorder using a Functional Random Forest algorithm

DSM-5 Autism Spectrum Disorder (ASD) comprises a set of neurodevelopmental disorders characterized by deficits in social communication and interaction and repetitive behaviors or restricted interests, and may both affect and be affected by multiple cognitive mechanisms. This study attempts to identify and characterize cognitive subtypes within the ASD population using our Functional Random Forest (FRF) machine learning classification model. This model trained a traditional random forest model on measures from seven tasks that reflect multiple levels of information processing. 47 ASD diagnosed and 58 typically developing (TD) children between the ages of 9 and 13 participated in this study. Our RF model was 72.7% accurate, with 80.7% specificity and 63.1% sensitivity. Using the random forest model, the FRF then measures the proximity of each subject to every other subject, generating a distance matrix between participants. This matrix is then used in a community detection algorithm to identify subgroups within the ASD and TD groups, and revealed 3 ASD and 4 TD putative subgroups with unique behavioral profiles. We then examined differences in functional brain systems between diagnostic groups and putative subgroups using resting-state functional connectivity magnetic resonance imaging (rsfcMRI). Chi-square tests revealed a significantly greater number of between group differences (p < .05) within the cingulo-opercular, visual, and default systems as well as differences in inter-system connections in the somato-motor, dorsal attention, and subcortical systems. Many of these differences were primarily driven by specific subgroups suggesting that our method could potentially parse the variation in brain mechanisms affected by ASD.

Improving resolution of dynamic communities in human brain networks through targeted node removal.

Current approaches to dynamic community detection in complex networks can fail to identify multi-scale community structure, or to resolve key features of community dynamics. We propose a targeted node removal technique to improve the resolution of community detection. Using synthetic oscillator networks with well-defined “ground truth” communities, we quantify the community detection performance of a common modularity maximization algorithm. We show that the performance of the algorithm on communities of a given size deteriorates when these communities are embedded in multi-scale networks with communities of different sizes, compared to the performance in a single-scale network. We demonstrate that targeted node removal during community detection improves performance on multi-scale networks, particularly when removing the most functionally cohesive nodes. Applying this approach to network neuroscience, we compare dynamic functional brain networks derived from fMRI data taken during both repetitive single-task and varied multi-task experiments. After the removal of regions in visual cortex, the most coherent functional brain area during the tasks, community detection is better able to resolve known functional brain systems into communities. In addition, node removal enables the algorithm to distinguish clear differences in brain network dynamics between these experiments, revealing task-switching behavior that was not identified with the visual regions present in the network. These results indicate that targeted node removal can improve spatial and temporal resolution in community detection, and they demonstrate a promising approach for comparison of network dynamics between neuroscientific data sets with different resolution parameters.

Catastrophe Reaction and Emotionalism.

The catastrophic reaction (CR; a disruptive and uncontrolled behavior triggered by anger, irritability, and hostility) and emotionalism (a condition of uncontrolled crying or laughing) are disorders of the emotional regulation and expression, the prevalence of which is underestimated in neurology. Their occurrence is an additional factor of poor outcome for neurologic patients. Although they have been recognized and completely described in their clinical manifestations more than a century ago, many issues remain unsolved regarding their pathogenesis and the respective role of the brain damage and psychological factors. Thus, if pathological crying and laughing can be linked to one or more lesions within the corticospinal tracts, the emotional lability and CR have uncertain connections within specific functional brain systems and seem to be influenced by personality factors or depression and anxiety generated by coping with a serious neurological disease. These epistemological difficulties are also the consequence of some methodological limits of the questionnaires and scales, which diagnose these disorders and for which the cut-off values between the normal and pathological condition could be questioned. Thus, their assessment requires new psychophysical. The CR and emotionalism manifest in association with several different neurological disease (degenerative, vascular, inflammatory, epilepsy) and psychiatric conditions as psychosis, mania, and mood disorders. Across these different diseases, the findings of common patterns of lesion location, cognitive dysfunction, emotional changes, and behavioral responses to new paradigms might clarify the pathogenesis and orient the treatment.

Contributions from outstanding young eating disorder investigators: What we are learning, how we are learning it, and where might we go next?

This is a time of striking progress in the field of eating disorders, and outstanding young psychological scientists are playing an important role in this progress. This special section provides a sample of this work, which is characterized by a diversity of research questions and methods. The importance of transdiagnostic processes that increase risk for both disordered eating and other dysfunction is reflected in articles that identify shared familial risk across disorders, integrate transdiagnostic and eating disorder-specific risk, and examine the impact of affective processing on restricting behavior. The importance of eating disorder-specific risk is reflected in an article on disorder-specific relations between hunger and taste. The importance of integrative risk models across levels of analysis is reflected in articles that investigate the heritable component of interactions between broad personality and disorder-specific risk factors, the momentary impact of personality traits on precipitants of binge-purge episodes, brain system function responses to environmental stressors, and cross-generational transmission of risk. The importance of further understanding the nature and scope of eating disorder pathology is reflected in a meta-analysis of purging disorder and an investigation of genetic effects on disordered eating in males. This commentary places these articles in the context of challenges facing the field and considers the future of eating disorders research. (PsycINFO Database Record

Clinically silent Alzheimer's and vascular pathologies influence brain networks supporting executive function in healthy older adults

Aging is associated with declines in executive function. We examined how executive functional brain systems are influenced by clinically silent Alzheimer's disease (AD) pathology and cerebral white-matter hyperintensities (WMHs). Twenty-nine younger adults and 34 cognitively normal older adults completed a working memory paradigm while functional magnetic resonance imaging was performed. Older adults further underwent lumbar cerebrospinal fluid draw for the assessment of AD pathology and FLAIR imaging for the assessment of WMHs. Accurate working memory performance in both age groups was associated with high fronto-visual functional connectivity (fC). However, in older adults, higher expression of fronto-visual fC was linked with lower levels of clinically silent AD pathology. In addition, AD pathology and WMHs were each independently related to increased functional magnetic resonance imaging response in the left dorsolateral prefrontal cortex, a pattern associated with slower task performance. Our results suggest that clinically silent AD pathology is related to lower expression of a fronto-visual fC pattern supporting executive task performance. Further, our findings suggest that AD pathology and WMHs appear to be linked with ineffective increases in frontal response in CN older adults.