Activation Likelihood Estimation Meta-analysis Research Articles

Seeking the "Beauty Center" in the Brain: A Meta-Analysis of fMRI Studies of Beautiful Human Faces and Visual Art.

During the past two decades, cognitive neuroscientists have sought to elucidate the common neural basis of the experience of beauty. Still, empirical evidence for such common neural basis of different forms of beauty is not conclusive. To address this question, we performed an activation likelihood estimation (ALE) meta-analysis on the existing neuroimaging studies of beauty appreciation of faces and visual art by nonexpert adults (49 studies, 982 participants, meta-data are available at https://osf.io/s9xds/ ). We observed that perceiving these two forms of beauty activated distinct brain regions: While the beauty of faces convergently activated the left ventral striatum, the beauty of visual art convergently activated the anterior medial prefrontal cortex (aMPFC). However, a conjunction analysis failed to reveal any common brain regions for the beauty of visual art and faces. The implications of these results are discussed.

Human Chemosignals and Brain Activity: A Preliminary Meta-analysis of the Processing of Human Body Odors.

Across phyla, chemosignals are a widely used form of social communication and increasing evidence suggests that chemosensory communication is present also in humans. Chemosignals can transfer, via body odors, socially relevant information, such as specific information about identity or emotional states. However, findings on neural correlates of processing of body odors are divergent. The aims of this meta-analysis were to assess the brain areas involved in the perception of body odors (both neutral and emotional) and the specific activation patterns for the perception of neutral body odor (NBO) and emotional body odor (EBO). We conducted an activation likelihood estimation (ALE) meta-analysis on 16 experiments (13 studies) examining brain activity during body odors processing. We found that the contrast EBO versus NBO resulted in significant convergence in the right middle frontal gyrus and the left cerebellum, whereas the pooled meta-analysis combining all the studies of human odors showed significant convergence in the right inferior frontal gyrus. No significant cluster was found for NBOs. However, our findings also highlight methodological heterogeneity across the existing literature. Further neuroimaging studies are needed to clarify and support the existing findings on neural correlates of processing of body odors.

Are there sex differences in brain activity during long-term memory? A systematic review and fMRI activation likelihood estimation meta-analysis

ABSTRACT The degree to which sex differences exist in the brain is a current topic of debate. In the present discussion paper, we reviewed eight functional magnetic resonance imaging (fMRI) papers to determine whether there are sex differences in brain activity during long-term memory retrieval. The objectives were: 1) to compare the experimental parameters in studies reporting significant versus null long-term memory sex differences, and 2) to identify whether specific brain regions were associated with sex differences during long-term memory. The following experimental parameters were extracted from each paper: the number of participants, the average age of participants, stimulus type(s), whether or not performance was matched, whether or not sex differences were reported, the type of between-subject statistical test used, and the contrast(s) employed. The particular experimental parameters employed in each study did not appear to determine whether sex differences were observed, as there were sex differences in all eight studies. An activation likelihood estimation (ALE) meta-analysis was conducted to identify brain regions activated to a greater degree by females than males or males than females. This ALE meta-analysis revealed sex differences (male > female) in the lateral prefrontal cortex, visual processing regions, parahippocampal cortex, and the cerebellum. This constitutes compelling evidence that there are substantial sex differences in brain activity during long-term memory retrieval. More broadly, the present findings question the widespread practice of collapsing across sex in the field of cognitive neuroscience.

Drawing on the brain: An ALE meta-analysis of functional brain activation during drawing

Art therapy researchers and practitioners are increasingly interested in the brain mechanisms underlying art therapy, an investigation area associated with almost no neuroimaging research. Lusebrink (2010) hypothesized that expression at different levels of the Expressive Therapies Continuum (ETC) would be supported by different patterns of functional brain activation. In the current study, we tested Lusebrink’s (2010) hypotheses through an activation likelihood estimation (ALE) meta-analysis of past neuroimaging research as participants engaged in different drawing tasks. Results supported our predictions that cognitive drawing, operationalized by internally-cued drawing stimuli or objective drawing content, would be associated with activation of the prefrontal and cingulate cortices. However, results failed to support our predictions that perceptual drawing, operationalized by externally-cued drawing stimuli and nonobjective drawing content, would be associated with activation of the ventral visual pathway in the temporal lobe. Perceptual drawing was associated with cerebellum, frontal, and parietal lobe activation (including the motor and somatosensory cortices). The dorsal visual pathway, largely in the parietal lobe, was engaged during cognitive and perceptual drawing. Our findings on patterns of brain activation can inform broader neuroscientific conceptualizations of the ETC framework and future directions for art therapy research and practice.

Neural Processes Underlying Mirror-Induced Visual Illusion: An Activation Likelihood Estimation Meta-Analysis

Introduction: Neuroimaging studies on neural processes associated with mirror-induced visual illusion (MVI) are growing in number. Previous systematic reviews on these studies used qualitative approaches.Objective: The present study conducted activation likelihood estimation (ALE) meta-analysis to locate the brain areas for unfolding the neural processes associated with the MVI.Method: We searched the CINAHL, MEDLINE, Scopus, and PubMed databases and identified eight studies (with 14 experiments) that met the inclusion criteria.Results: Contrasting with a rest condition, strong convergence in the bilateral primary and premotor areas and the inferior parietal lobule suggested top-down motor planning and execution. In addition, convergence was identified in the ipsilateral precuneus, cerebellum, superior frontal gyrus, and superior parietal lobule, clusters corresponding to the static hidden hand indicating self-processing operations, somatosensory processing, and motor control. When contrasting with an active movement condition, additional substantial convergence was revealed in visual-related areas, such as the ipsilateral cuneus, fusiform gyrus, middle occipital gyrus (visual area V2) and lingual gyrus, which mediate basic visual processing.Conclusions: To the best of our knowledge, the current meta-analysis is the first to reveal the visualization, mental rehearsal and motor-related processes underpinning the MVI and offers theoretical support on using MVI as a clinical intervention for post-stroke patients.

Do intrinsic brain functional networks predict working memory from childhood to adulthood?

Working memory (WM) is defined as the ability to maintain a representation online to guide goal‐directed behavior. Its capacity in early childhood predicts academic achievements in late childhood and its deficits are found in various neurodevelopmental disorders. We employed resting‐state fMRI (rs‐fMRI) of 468 participants aged from 4 to 55 years and connectome‐based predictive modeling (CPM) to explore the potential predictive power of intrinsic functional networks to WM in preschoolers, early and late school‐age children, adolescents, and adults. We defined intrinsic functional networks among brain regions identified by activation likelihood estimation (ALE) meta‐analysis on existing WM functional studies (ALE‐based intrinsic functional networks) and intrinsic functional networks generated based on the whole brain (whole‐brain intrinsic functional networks). We employed the CPM on these networks to predict WM in each age group. The CPM using the ALE‐based and whole‐brain intrinsic functional networks predicted WM of individual adults, while the prediction power of the ALE‐based intrinsic functional networks was superior to that of the whole‐brain intrinsic functional networks. Nevertheless, the CPM using the whole‐brain but not the ALE‐based intrinsic functional networks predicted WM in adolescents. And, the CPM using neither the ALE‐based nor whole‐brain networks predicted WM in any of the children groups. Our findings showed the trend of the prediction power of the intrinsic functional networks to cognition in individuals from early childhood to adulthood.

Individuals with the post-traumatic stress disorder process emotions in subcortical regions irrespective of cognitive engagement: a meta-analysis of cognitive and emotional interface.

Post-traumatic stress disorder (PTSD) manifests as emotional suffering and problem-solving impairments under extreme stress. This meta-analysis aimed to pool the findings from all the studies examining emotion and cognition in individuals with PTSD to develop a robust mechanistic understanding of the related brain dysfunction. We identified primary studies through a comprehensive literature search of the MEDLINE and PsychINFO databases. The GingerALE software (version 2.3.6) from the BrainMap Project was used to conduct activation likelihood estimation meta-analyses of the eligible studies for cognition, emotion and interface of both. Relative to the non-clinical (NC) group, the PTSD group showed greater activation during emotional tasks in the amygdala and parahippocampal gyrus. In contrast, the NC group showed significantly greater activation in the bilateral anterior cingulate cortex (ACC) than did the PTSD group in the emotional tasks. When both emotional and cognitive processing were evaluated, the PTSD group showed significantly greater activation in the striatum than did the NC group. No differences in activation between the PTSD and NC groups were noted when only the cognitive systems were examined. Individuals with PTSD exhibited overactivity in the subcortical regions, i.e., amygdala and striatum, when processing emotions. Underactivity in the emotional and cognitive processing intermediary cortex, i.e., the ACC, was especially prominent in individuals with PTSD relative to the NC population following exposure to emotional stimuli. These findings may explain the trauma-related fear, irritability, and negative effects as well as the concentration difficulties during cognitive distress associated with emotional arousal, that are commonly observed in individuals with PTSD.

133 - A systematic review and activation likelihood estimation meta-analysis of the central innervation of the lower urinary tract: Pelvic floor motor control and micturition

133 - A systematic review and activation likelihood estimation meta-analysis of the central innervation of the lower urinary tract: Pelvic floor motor control and micturition

Brain Network Underlying Executive Functions in Gambling and Alcohol Use Disorders: An Activation Likelihood Estimation Meta-Analysis of fMRI Studies.

Background: Neuroimaging and neuropsychological studies have suggested that common features characterize both Gambling Disorder (GD) and Alcohol Use Disorder (AUD), but these conditions have rarely been compared. Methods: We provide evidence for the similarities and differences between GD and AUD in neural correlates of executive functions by performing an activation likelihood estimation meta-analysis of 34 functional magnetic resonance imaging studies involving executive function processes in individuals diagnosed with GD and AUD and healthy controls (HC). Results: GD showed greater bilateral clusters of activation compared with HC, mainly located in the head and body of the caudate, right middle frontal gyrus, right putamen, and hypothalamus. Differently, AUD showed enhanced activation compared with HC in the right lentiform nucleus, right middle frontal gyrus, and the precuneus; it also showed clusters of deactivation in the bilateral middle frontal gyrus, left middle cingulate cortex, and inferior portion of the left putamen. Conclusions: Going beyond the limitations of a single study approach, these findings provide evidence, for the first time, that both disorders are associated with specific neural alterations in the neural network for executive functions.

A Systematic Review and Activation Likelihood Estimation Meta-Analysis of fMRI Studies on Sweet Taste in Humans

ABSTRACTBackgroundThe reward value of palatable foods is often cited as an important influence on eating behaviors, including intake of sugars. However, human neuroimaging studies have generated conflicting evidence on the basic neural representation of taste and reward responses to caloric sweeteners (sucrose and glucose), and most relevant studies have used small subject numbers.ObjectiveWe conducted a systematic review and a coordinate-based meta-analysis of studies reporting brain responses to oral sugar solutions.MethodsA systematic search of MEDLINE, Scopus, and PsycINFO through October 2019 identified fMRI studies (in healthy human adults, including those with overweight or obesity) assessing differences in responses to purified sweet and nonsweet taste stimuli. Data were extracted with the primary objective of quantifying evidence for the activation of brain regions associated with caloric sweet taste sensation. We used activation likelihood estimation meta-analysis methods. We also performed multiple sensitivity analyses to assess the generality of effects.ResultsOf 455 unique articles, 15 met the criteria for inclusion. These contributed to 2 primary meta-analyses: 1) sucrose (13 experiments, 179 coordinates, n = 241) and 2) sucrose + glucose (16 experiments, 209 coordinates, n = 262). Consistent activation was apparent in primary taste areas: insula (69.2% of studies) and opercular cortex (76.9% of studies), precentral gyri (53.9% of studies), and globus pallidus and postcentral gyrus (30.8% of studies for each). Evidence of reward activity (caudate) was seen in the primary analyses (30.8% of studies) but not in sensitivity analysis.ConclusionsWe confirm the importance of primary taste areas for gustatory processing in human adults. We also provide tentative evidence for reward-related caudate activity in relation to the sweet taste of caloric sugars. A number of factors affect the observation and interpretation of brain responses, including reward-related activity. Firm conclusions require confirmation with large data set studies.

Mapping the artistic brain: Common and distinct neural activations associated with musical, drawing, and literary creativity.

Whether creativity is a domain‐general or domain‐specific ability has been a topic of intense speculation. Although previous studies have examined domain‐specific mechanisms of creative performance, little is known about commonalities and distinctions in neural correlates across different domains. We applied activation likelihood estimation (ALE) meta‐analysis to identify the brain activation of domain‐mechanisms by synthesizing functional neuroimaging studies across three forms of artistic creativity: music improvisation, drawing, and literary creativity. ALE meta‐analysis yielded a domain‐general pattern across three artistic forms, with overlapping clusters in the presupplementary motor area (pre‐SMA), left dorsolateral prefrontal cortex, and right inferior frontal gyrus (IFG). Regarding domain‐specificity, musical creativity was associated with recruitment of the SMA‐proper, bilateral IFG, left precentral gyrus, and left middle frontal gyrus (MFG) compared to the other two artistic forms; drawing creativity recruited the left fusiform gyrus, left precuneus, right parahippocampal gyrus, and right MFG compared to musical creativity; and literary creativity recruited the left angular gyrus and right lingual gyrus compared to musical creativity. Contrasting drawing and literary creativity revealed no significant differences in neural activation, suggesting that these domains may rely on a common neurocognitive system. Overall, these findings reveal a central, domain‐general system for artistic creativity, but with each domain relying to some degree on domain‐specific neural circuits.

Neural correlates of successful emotional episodic encoding and retrieval: An SDM meta-analysis of neuroimaging studies

Episodic memory for emotional events is typically enhanced and engages additional brain mechanisms relative to episodic memory for neutral events. Many functional magnetic resonance imaging (fMRI) studies have probed the neural basis of this emotional enhancement effect on encoding processes, while relatively fewer studies have examined retrieval. Neuroimaging meta-analysis methods can summarize the brain regions associated with emotional episodic memory that are consistently activated across multiple studies. A previous ALE (Activation Likelihood Estimation) meta-analysis identified consistent activations associated with successful encoding of episodic emotional memory in the amygdala, hippocampus, and in multiple neocortical regions (Murty et al., 2010). However, since that study, meta-analysis methods have improved, and many new relevant neuroimaging studies have been published. Moreover, although qualitative reviews have summarized brain activations related to the successful retrieval of emotional episodic memory, no corresponding quantitative meta-analyses have yet been reported. Here we conducted neuroimaging meta-analyses of successful emotional memory encoding and rretrieval using Seed-based d Mapping (SDM). Relevant neuroimaging studies reporting whole-brain fMRI correlates of successful encoding and retrieval of emotional episodic memory were selected for analysis. For successful emotional memory encoding, SDM activations were found bilaterally in the medial temporal lobe (amygdala, hippocampus, entorhinal cortex, perirhinal cortex, and parahippocampal cortex), bilaterally in visual processing regions (middle temporal, gyrus, fusiform gyrus and occipital cortex) and bilaterally in the temporal pole, orbitofrontal cortex, insula, putamen, and the inferior and middle temporal gyri. In contrast to the prior meta-analysis, SDM activations were not observed in the inferior frontal gyrus or in parietal regions. For successful emotional episodic memory retrieval, SDM activations were observed in the medial temporal lobe (bilateral amygdala, left hippocampus, and left entorhinal cortex and perirhinal cortex), visual processing regions (bilateral occipital cortex and right middle temporal gyrus), prefrontal cortex (bilateral orbitofrontal cortex, bilateral inferior frontal gyrus, bilateral precentral gyrus, left middle frontal gyrus, right frontal pole) and other regions in the left hemisphere including the temporal pole, insula, putamen, angular gyrus, and parietal opercular cortex. Considerable overlap was observed between the encoding and retrieval meta-analysis maps in the medial temporal lobe (bilateral amygdala, left hippocampus, entorhinal, and perirhinal cortex), visual processing regions (bilateral occipital cortex, right middle temporal gyrus), and other regions including the left orbitofrontal cortex, left insula, left putamen, left pallidum, and left temporal pole. The current findings add to current understanding of the role of the amygdala, hippocampus, and neocortical regions in the successful encoding and retrieval of emotional episodic memory, clarify and provide an important summary of the current literature in this area, and have implications for current theories of emotional episodic memory encoding and retrieval.

Structural and functional changes in the brain of patients with Crohn's disease: an activation likelihood estimation meta-analysis.

Multiple reports for brain functional and structural alterations in patients with Crohn's disease (CD) were published. The current study aimed to meta-analyze the existing neuroimaging data and hence produce a brain map revealing areas with functional and structural differences between patients with CD and healthy controls. Original studies published until 2019 were identified from Scopus, Web of Science and PubMed databases, and included into the analysis if they reported relevant results from task-related or resting state functional magnetic resonance imaging (fMRI or rsfMRI) or voxel-based morphometry (VBM), in the form of standardized brain coordinates based on whole-brain analysis. The brain coordinates and sample size of significant results were extracted from eligible studies to be meta-analyzed with the activation likelihood estimation method using the GingerALE software. Sixteen original studies comprised of a total of 865 participants fulfilled the inclusion criteria. Compared to healthy controls, patients with CD had reduced resting state brain connectivity in the paracentral lobule and cingulate gyrus as well as reduced grey matter volume in the medial frontal gyrus. No significant results were found vice versa. These neural correlates allow a better understanding on the effects of CD on the pain expectation, emotion, and quality of life of patients and potentially serve as useful biomarkers for evaluating treatment efficacy.

A Meta-Analysis of Gray Matter Differences Between Bilinguals and Monolinguals.

Bilingualism is of great interest to the neuroscience of language, and understanding the anatomical changes associated with second language learning help inform theories of bilingual advantage across the lifespan. While the literature on structural differences between bilinguals and monolinguals is robust, relatively few studies of gray matter (GM) have directly compared bilinguals with monolinguals in a whole-brain analysis. Overall, this and heterogeneity of study samples and methodology have led to a lack of clear anatomical support for major theories. Here, we engage in an activation likelihood estimate (ALE) meta-analysis of voxel-based morphometry (VBM) studies of GM for cases that directly compare bilingual and monolingual subjects in a whole-brain analysis. The analysis (sixteen foci, from ten contrasts across eight studies) resulted in one cluster located primarily within the anterior lobe of the right cerebellum. However, when the one pediatric study was removed, the analysis revealed no consistent results across the studies included in this meta-analysis. This suggests that for VBM studies of bilingual and monolingual adults there is considerable heterogeneity of results that complicate the understanding of the bilingual brain. Future studies will need to include larger, more well-defined samples and interrogate more fine-grained anatomical features such as cortical thickness and surface area in order to more fully examine the anatomical changes associated with bilingualism across the lifespan.

Explore structural and functional brain changes in insomnia disorder: A PRISMA-compliant whole brain ALE meta-analysis for multimodal MRI.

Inconsistent results for comparison between insomnia disorder (ID) patients and healthy controls (HC) were obtained from previous neuroimaging studies. An activation likelihood estimation (ALE) meta-analysis was made for multimodal neuroimaging in ID. ALE analysis indicated that ID patients showed significant gray matter reductions in the right middle frontal gyrus (MFG), compared to HC. Regarding positron emission tomography studies, ALE analysis showed reduced relative cerebral glucose metabolism in the right amygdala, the right anterior cingulate cortex (ACC), and the right posterior cingulate gyrus (PCG) in ID patients, compared to HC. Regarding diffusion tensor imaging studies, the present study indicated that ID patients showed reduced fractional anisotropy values in the left putamen and the right caudate body, compared to HC. Additionally, ID patients showed reduced amplitude of low frequency fluctuations (ALFF) in the left fusiform gyrus (FG), the left middle temporal gyrus (MTG), the right MTG, the right anterior lobe (AL), and the left PCG, compared to HC. ID patients showed increased ALFF in the left MFG, compared to HC. ID patients showed reduced regional homogeneity (ReHo) in the left parahippocampal gyrus, the left sublobar, the left cuneus, the left precentral gyrus (PCG), the right AL, the right ACC, and the right PCG, compared to HC. ID patients showed increased ReHo in the left FG, the left precuneus, and the right cingulate gyrus, compared to HC. Moreover, the ALE analysis showed hypoactivation relative to HC in the left superior temporal gyrus (STG), the left MTG, the right inferior frontal gyrus, the right cuneus, and the right STG in ID patients. Via this ALE meta-analysis, we obtained these key regions suffering from deficits in ID.

ALE meta-analysis, its role in node identification and the effects on estimates of local network organization.

Functional connectivity analyses for task-based fMRI data are generally preceded by methods for identification of network nodes. As there is no general canonical approach to identifying network nodes, different identification techniques may exert different effects on inferences drawn regarding functional network properties. Here, we compared the impact of two different node identification techniques on estimates of local node importance (based on Degree Centrality, DC) in two working memory domains: verbal and visual. The two techniques compared were the commonly used Activation Likelihood Estimate (ALE) technique (with node locations based on data aggregation), against a hybrid technique, Experimentally Derived Estimation (EDE). In the latter, ALE was first used to isolate regions of interest; then participant-specific nodes were identified based on individual-participant local maxima. Time series were extracted at each node for each dataset and subsequently used in functional connectivity analysis to: (1) assess the impact of choice of technique on estimates of DC, and (2) assess the difference between the techniques in the ranking of nodes (based on DC) in the networks they produced. In both domains, we found a significant Technique by Node interaction, signifying that the two techniques yielded networks with different DC estimates. Moreover, for the majority of participants, node rankings were uncorrelated between the two techniques (85% for the verbal working memory task and 92% for the visual working memory task). The latter effect is direct evidence that the identification techniques produced different rankings at the level of individual participants. These results indicate that node choice in task-based fMRI data exerts downstream effects that will impact interpretation and reverse inference regarding brain function.

Cerebellar Contributions to Proactive and Reactive Control in the Stop Signal Task: A Systematic Review and Meta-Analysis of Functional Magnetic Resonance Imaging Studies.

The cerebellum facilitates and modulates cognitive functions using forward and inverse internal models to predict and control behavior, respectively. Despite neuroimaging evidence that regions of the cerebellum are active during executive function (EF) tasks in general, little is known about the cerebellum's role in specific EFs and their underlying neural networks. Inhibitory control specifically may be facilitated by cerebellar internal models predicting responses during proactive control (withholding), and controlling responses during reactive control (inhibiting). The stop signal task (SST) is an inhibitory control task often used in neuroimaging studies to measure neural responses to both proactive and reactive control. Thus, in this review, we examine evidence for the cerebellum's role in inhibitory control by reviewing studies of healthy adults that utilized the SST in event-related functional magnetic resonance imaging (fMRI) experiments. Twenty-one studies that demonstrated cerebellar results were eligible for review, including 749 participants, 28 contrasts, and 38 cerebellar clusters. We also performed activation likelihood estimation (ALE) meta-analysis of contrasts derived from reviewed studies. This review illustrates evidence for the cerebellum participating in inhibitory control independent of motor control. Most significant cerebellar clusters were located in the left posterior cerebellum, suggesting that it communicates with the established cortical right-lateralized inhibitory control network. Cerebellar activity was most consistently observed for contrasts that measured proactive control, and ALE analysis confirmed that left Crus I is most likely to be activated in studies of proactive control measuring monitoring and anticipation. Results suggest that the left posterior cerebellum may communicate with right frontal and parietal cortices, using forward models to predict appropriate responses. Reactive control contrasts indicated a possible role for cerebellar regions in enhancing inhibition efficiency through inverse models, but ALE meta-analysis did not confirm this hypothesis. Limitations in the current literature, clinical implications, and directions for future research are discussed.

Social brain dysfunctionality in individuals with autism spectrum disorder and their first-degree relatives: An activation likelihood estimation meta-analysis

The social brain hypothesis is regarded as a powerful theory to understand social cognition. Individuals with autism spectrum disorder (ASD) have specific deficits in social and communicative behavior, but the exact relationship between these deficits and abnormalities in the social brain remains unclear. The high heritability of this disorder makes it important to focus on the first-degree relatives of those affected. Research focusing on genetically at-risk (yet healthy) relatives of patients with ASD is critical to the study of neuroimaging endophenotypes. We conducted a voxel-wise activation likelihood estimation (ALE) meta-analysis of 9 functional neuroimaging studies published during the period from 2006 to 2018. These studies included 200 individuals with ASD, 216 unaffected family members (UF), and 235 typical development controls (TD). The voxel-wise significance threshold was p < 0.01 (uncorrected p = 0.001).The ALE meta-analyses showed hyperactivation in the inferior frontal gyrus (IFG) and superior temporal gyrus (STG) among individuals with ASD and UF, compared with TD individuals. Group comparisons showed greater likelihood of hyperactivation in the amygdala for ASD, compared with UF and TD.

Food cue recruits increased reward processing and decreased inhibitory control processing in the obese/overweight: An activation likelihood estimation meta-analysis of fMRI studies

IntroductionGrowing researches have shown that obese/overweight and healthy weight individuals exhibit different neural responses to food-related stimuli. Accordingly, researchers proposed several theories to explain these differences. Hereon, meta-analyses were conducted using activation likelihood estimation (ALE) to verify these theories and specify the reason of overeating from two aspects. Materials and MethodsPubmed, Web of Science and Neurosynth were searched for the current study and screened according to inclusion criteria. Firstly, neural responses to visual food cues versus non-food images were compared between obese/overweight and healthy weight individuals. Then, neural activation to high-calorie food images versus low-calorie food/non-food visual stimuli was further investigated among the two populations. Coordinates in included studies were recorded and analysed by Ginger ALE software under threshold at uncorrected p < 0.001 with cluster-level p < 0.05 (cFWE). ResultsEleven and seven studies were found in the first and second set of meta-analysis, respectively. The first meta-analysis showed that obese/overweight have hyper-responsivity in reward area and hypo-responsivity in both gustatory processing and inhibitory control area. The second meta-analysis indicated that the reward responsivity in the obese/overweight individuals was amplified and healthy weight individuals had higher activation in areas associated with gustatory processing in response to high-calorie food images. ConclusionsOur results showed that the obese/overweight exhibit hyper-responsivity in brain regions involved in reward processing for visual food cue which provide strong support for incentive-sensitization theory of obesity and healthy weight individuals showed higher response in inhibitory control region which support the inhibitory control deficit theory of obesity.

Identification of Common Neural Circuit Disruptions in Emotional Processing Across Psychiatric Disorders.

Disrupted emotional processing is a common feature of many psychiatric disorders. The authors investigated functional disruptions in neural circuitry underlying emotional processing across a range of tasks and across psychiatric disorders through a transdiagnostic quantitative meta-analysis of published neuroimaging data. A PubMed search was conducted for whole-brain functional neuroimaging findings published through May 2018 that compared activation during emotional processing tasks in patients with psychiatric disorders (including schizophrenia, bipolar or unipolar depression, anxiety, and substance use) to matched healthy control participants. Activation likelihood estimation (ALE) meta-analyses were conducted on peak voxel coordinates to identify spatial convergence. The 298 experiments submitted to meta-analysis included 5,427 patients and 5,491 control participants. ALE across diagnoses and patterns of patient hyper- and hyporeactivity demonstrated abnormal activation in the amygdala, the hippocampal/parahippocampal gyri, the dorsomedial/pulvinar nuclei of the thalamus, and the fusiform gyri, as well as the medial and lateral dorsal and ventral prefrontal regions. ALE across disorders but considering directionality demonstrated patient hyperactivation in the amygdala and the hippocampal/parahippocampal gyri. Hypoactivation was found in the medial and lateral prefrontal regions, most pronounced during processing of unpleasant stimuli. More refined disorder-specific analyses suggested that these overall patterns were shared to varying degrees, with notable differences in patterns of hyper- and hypoactivation. These findings demonstrate a pattern of neurocircuit disruption across major psychiatric disorders in regions and networks key to adaptive emotional reactivity and regulation. More specifically, disruption corresponded prominently to the "salience" network, the ventral striatal/ventromedial prefrontal "reward" network, and the lateral orbitofrontal "nonreward" network. Consistent with the Research Domain Criteria initiative, these findings suggest that psychiatric illness may be productively formulated as dysfunction in transdiagnostic neurobehavioral phenotypes such as neurocircuit activation.