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Cognitive, Affective & Behavioral... Feb 2024All experiences preserved within episodic memory contain information on the space and time of events. The hippocampus is the main brain region involved in processing... (Meta-Analysis)
Meta-Analysis Review
All experiences preserved within episodic memory contain information on the space and time of events. The hippocampus is the main brain region involved in processing spatial and temporal information for incorporation within episodic memory representations. However, the other brain regions involved in the encoding and retrieval of spatial and temporal information within episodic memory are unclear, because a systematic review of related studies is lacking and the findings are scattered. The present study was designed to integrate the results of functional magnetic resonance imaging and positron emission tomography studies by means of a systematic review and meta-analysis to provide converging evidence. In particular, we focused on identifying the brain regions involved in the retrieval of spatial and temporal information. We identified a spatial retrieval network consisting of the inferior temporal gyrus, parahippocampal gyrus, superior parietal lobule, angular gyrus, and precuneus. Temporal context retrieval was supported by the dorsolateral prefrontal cortex. Thus, the retrieval of spatial and temporal information is supported by different brain regions, highlighting their different natures within episodic memory.
Topics: Humans; Memory, Episodic; Brain Mapping; Brain; Temporal Lobe; Parietal Lobe; Magnetic Resonance Imaging; Mental Recall
PubMed: 38030912
DOI: 10.3758/s13415-023-01140-1 -
Brain Sciences Aug 2022Deficits in social cognition and function are characteristic of dementia, commonly accompanied by a loss of awareness of the presence or extent of these deficits. This... (Review)
Review
Deficits in social cognition and function are characteristic of dementia, commonly accompanied by a loss of awareness of the presence or extent of these deficits. This lack of awareness can impair social relationships, increase patients' and carers' burden, and contribute to increased rates of institutionalization. Despite clinical importance, neural correlates of this complex phenomenon remain unclear. We conducted a systematic search of five electronic databases to identify functional and structural neuroimaging studies investigating the neural correlates of impaired awareness of social cognition and function in any dementia type. We rated study quality and conducted a narrative synthesis of the results of the eight studies that met the predefined eligibility criteria. Across these studies, deficits in awareness of impairments in social cognition and function were associated with structural or functional abnormalities in the frontal pole, orbitofrontal cortex, temporal pole, middle temporal gyrus, inferior temporal gyrus, fusiform gyrus, amygdala, hippocampus, parahippocampal gyrus, and insula. Several identified regions overlap with established neural correlates of social cognition. More research is needed to understand awareness of social cognition and function and how this becomes impaired in dementia to improve neuroscientific understanding, aid the identification of this problematic symptom, and target interventions to reduce burden and improve care.
PubMed: 36138872
DOI: 10.3390/brainsci12091136 -
Frontiers in Psychiatry 2022Previous voxel-based morphometric (VBM) and functional magnetic resonance imaging (fMRI) studies have shown changes in brain structure and function in cocaine addiction...
BACKGROUND
Previous voxel-based morphometric (VBM) and functional magnetic resonance imaging (fMRI) studies have shown changes in brain structure and function in cocaine addiction (CD) patients compared to healthy controls (HC). However, the results of these studies are poorly reproducible, and it is unclear whether there are common and specific neuroimaging changes. This meta-analysis study aimed to identify structural, functional, and multimodal abnormalities in CD patients.
METHODS
The PubMed database was searched for VBM and task-state fMRI studies performed in CD patients between January 1, 2010, and December 31, 2021, using the SEED-BASE d MAP software package to perform two independent meta-groups of functional neural activation and gray matter volume, respectively. Analysis, followed by multimodal analysis to uncover structural, functional, and multimodal abnormalities between CD and HC.
RESULTS
The meta-analysis included 14 CD fMRI studies (400 CD patients and 387 HCs) and 11 CD VBM studies (368 CD patients and 387 controls). Structurally, VBM analysis revealed significantly lower gray matter volumes in the right superior temporal gyrus, right insula, and right retrocentral gyrus than in the HC. On the other hand, the right inferior parietal gyrus increased in gray matter (GM) volume in CD patients. Functionally, fMRI analysis revealed activation in the right temporal pole, right insula, and right parahippocampal gyrus. In the right inferior parietal gyrus, the left inferior parietal gyrus, the left middle occipital gyrus, and the right middle frontal gyrus, the degree of activation was lower.
CONCLUSION
This meta-analysis showed that CD patients had significant brain GM and neural changes compared with normal controls. Furthermore, multi-domain assessments capture different aspects of neuronal alterations in CD, which may help develop effective interventions for specific functions.
PubMed: 35815007
DOI: 10.3389/fpsyt.2022.927075 -
Neuropsychologia Nov 2014Social Anxiety Disorder (SAD) and Williams-Beuren Syndrome (WS) are two conditions which seem to be at opposite ends in the continuum of social fear but show compromised... (Meta-Analysis)
Meta-Analysis Review
Common and distinct neural correlates of facial emotion processing in social anxiety disorder and Williams syndrome: A systematic review and voxel-based meta-analysis of functional resonance imaging studies.
BACKGROUND
Social Anxiety Disorder (SAD) and Williams-Beuren Syndrome (WS) are two conditions which seem to be at opposite ends in the continuum of social fear but show compromised abilities in some overlapping areas, including some social interactions, gaze contact and processing of facial emotional cues. The increase in the number of neuroimaging studies has greatly expanded our knowledge of the neural bases of facial emotion processing in both conditions. However, to date, SAD and WS have not been compared.
METHODS
We conducted a systematic review of functional magnetic resonance imaging (fMRI) studies comparing SAD and WS cases to healthy control participants (HC) using facial emotion processing paradigms. Two researchers conducted comprehensive PubMed/Medline searches to identify all fMRI studies of facial emotion processing in SAD and WS. The following search key-words were used: "emotion processing"; "facial emotion"; "social anxiety"; "social phobia"; "Williams syndrome"; "neuroimaging"; "functional magnetic resonance"; "fMRI" and their combinations, as well as terms specifying individual facial emotions. We extracted spatial coordinates from each study and conducted two separate voxel-wise activation likelihood estimation meta-analyses, one for SAD and one for WS.
RESULTS
Twenty-two studies met the inclusion criteria: 17 studies of SAD and five of WS. We found evidence for both common and distinct patterns of neural activation. Limbic engagement was common to SAD and WS during facial emotion processing, although we observed opposite patterns of activation for each disorder. Compared to HC, SAD cases showed hyperactivation of the amygdala, the parahippocampal gyrus and the globus pallidus. Compared to controls, participants with WS showed hypoactivation of these regions. Differential activation in a number of regions specific to either condition was also identified: SAD cases exhibited greater activation of the insula, putamen, the superior temporal gyrus, medial frontal regions and the cuneus, while WS subjects showed decreased activation in the inferior region of the parietal lobule.
CONCLUSIONS
The identification of limbic structures as a shared correlate and the patterns of activation observed for each condition may reflect the aberrant patterns of facial emotion processing that the two conditions share, and may contribute to explaining part of the underlying neural substrate of exaggerated/diminished fear responses to social cues that characterize SAD and WS respectively. We believe that insights from WS and the inclusion of this syndrome as a control group in future experimental studies may improve our understanding of the neural correlates of social fear in general, and of SAD in particular.
Topics: Brain; Emotions; Facial Recognition; Humans; Magnetic Resonance Imaging; Phobia, Social
PubMed: 25194208
DOI: 10.1016/j.neuropsychologia.2014.08.027 -
Progress in Neuro-psychopharmacology &... Dec 2022Reactive aggression in response to perceived threat or provocation is part of humans' adaptive behavioral repertoire. However, high levels of aggression can lead to the... (Meta-Analysis)
Meta-Analysis
Brain responses in aggression-prone individuals: A systematic review and meta-analysis of functional magnetic resonance imaging (fMRI) studies of anger- and aggression-eliciting tasks.
Reactive aggression in response to perceived threat or provocation is part of humans' adaptive behavioral repertoire. However, high levels of aggression can lead to the violation of social and legal norms. Understanding brain function in individuals with high levels of aggression as they process anger- and aggression-eliciting stimuli is critical for refining explanatory models of aggression and thereby improving interventions. Three neurobiological models of reactive aggression - the limbic hyperactivity, prefrontal hypoactivity, and dysregulated limbic-prefrontal connectivity models - have been proposed. However, these models are based on neuroimaging studies involving mainly non-aggressive individuals, leaving it unclear which model best describes brain function in those with a history of aggression. We conducted a systematic literature search (PubMed and Psycinfo) and Multilevel Kernel Density meta-analysis (MKDA) of nine functional magnetic resonance imaging (fMRI) studies (eight included in the between-group analysis [i.e., aggression vs. control groups], five in the within-group analysis). Studies examined brain responses to tasks putatively eliciting anger and aggression in individuals with a history of aggression alone and relative to controls. Individuals with a history of aggression exhibited greater activity in the superior temporal gyrus and in regions comprising the cognitive control and default mode networks (right posterior cingulate cortex, precentral gyrus, precuneus, right inferior frontal gyrus) during reactive aggression relative to baseline conditions. Compared to controls, individuals with a history of aggression exhibited increased activity in limbic regions (left hippocampus, left amygdala, left parahippocampal gyrus) and temporal regions (superior, middle, inferior temporal gyrus), and reduced activity in occipital regions (left occipital cortex, left calcarine cortex). These findings lend support to the limbic hyperactivity model in individuals with a history of aggression, and further indicate altered temporal and occipital activity in anger- and aggression-eliciting conditions involving face and speech processing.
Topics: Aggression; Anger; Brain; Brain Mapping; Humans; Magnetic Resonance Imaging; Prefrontal Cortex
PubMed: 35803398
DOI: 10.1016/j.pnpbp.2022.110596 -
Neuropsychologia Oct 2015Two central traits present in the most influential models of personality characterize the response to positive and, respectively, negative emotional events. Negative... (Meta-Analysis)
Meta-Analysis Review
Two central traits present in the most influential models of personality characterize the response to positive and, respectively, negative emotional events. Negative emotionality (NE)-related traits are linked to vulnerability to mood and anxiety disorders; this has fuelled a special interest in examining stable differences in brain morphology associated to these traits. Structural imaging methods including voxel-based morphometry, cortical thickness analysis and diffusion tensor imaging (DTI) have yielded inconclusive and sometimes contradictory results. This review summarizes the findings reported to date through these methods and discusses them in relation to the functional imaging results. To detect topographic convergence between studies showing positive and, respectively, negative grey matter associations with NE-traits, activation likelihood estimation (ALE) meta-analyses of VBM studies were performed. Individuals scoring high on NE-related traits show consistent morphological differences in a left-lateralized circuit: higher grey matter volume (GMV) in amygdala and anterior parahippocampal gyrus and lower GMV in the orbitofrontal cortex extending into perigenual anterior cingulate cortex. Most DTI studies indicate reduced white matter integrity in various brain regions and tracts, particularly in the uncinate fasciculus and in cingulum bundle. These results show that the behavioural phenotype associated to NE traits is reflected in structural differences within the cortico-limbic system, suggesting alterations in information processing and transmission. The results are discussed from the perspective of neuron-glia interactions. Future directions are outlined based on recent developments in structural imaging techniques.
Topics: Brain; Emotions; Humans; Personality
PubMed: 26265397
DOI: 10.1016/j.neuropsychologia.2015.08.007 -
The conscious processing of emotion in depression disorder: a meta-analysis of neuroimaging studies.Frontiers in Psychiatry 2023Depression is generally accompanied by a disturbed conscious processing of emotion, which manifests as a negative bias to facial/voice emotion information and a...
BACKGROUND
Depression is generally accompanied by a disturbed conscious processing of emotion, which manifests as a negative bias to facial/voice emotion information and a decreased accuracy in emotion recognition tasks. Several studies have proved that abnormal brain activation was responsible for the deficit function of conscious emotion recognition in depression. However, the altered brain activation related to the conscious processing of emotion in depression was incongruent among studies. Therefore, we conducted an activation likelihood estimation (ALE) analysis to better understand the underlying neurophysiological mechanism of conscious processing of emotion in depression.
METHOD
Electronic databases were searched using the search terms "depression," "emotion recognition," and "neuroimaging" from inceptions to April 10th, 2023. We retrieved trials which explored the neuro-responses of depressive patients to explicit emotion recognition tasks. Two investigators independently performed literature selection, data extraction, and risk of bias assessment. The spatial consistency of brain activation in conscious facial expressions recognition was calculated using ALE. The robustness of the results was examined by Jackknife sensitivity analysis.
RESULTS
We retrieved 11,365 articles in total, 28 of which were included. In the overall analysis, we found increased activity in the middle temporal gyrus, superior temporal gyrus, parahippocampal gyrus, and cuneus, and decreased activity in the superior temporal gyrus, inferior parietal lobule, insula, and superior frontal gyrus. In response to positive stimuli, depressive patients showed hyperactivity in the medial frontal gyrus, middle temporal gyrus, and insula (uncorrected < 0.001). When receiving negative stimuli, a higher activation was found in the precentral gyrus, middle frontal gyrus, precuneus, and superior temporal gyrus (uncorrected < 0.001).
CONCLUSION
Among depressive patients, a broad spectrum of brain areas was involved in a deficit of conscious emotion processing. The activation of brain regions was different in response to positive or negative stimuli. Due to potential clinical heterogeneity, the findings should be treated with caution.
SYSTEMATIC REVIEW REGISTRATION
https://inplasy.com/inplasy-2022-11-0057/, identifier: 2022110057.
PubMed: 37448490
DOI: 10.3389/fpsyt.2023.1099426 -
The International Journal of... Jul 2017Physical activity may play a role in both the prevention and slowing of brain volume loss and may be beneficial in terms of improving the functional connectivity of... (Review)
Review
Physical activity may play a role in both the prevention and slowing of brain volume loss and may be beneficial in terms of improving the functional connectivity of brain regions. But much less is known about the potential benefit of aerobic exercise for the structure and function of the default mode network (DMN) brain regions. This systematic review examines the effects of aerobic exercise on the structure and function of DMN brain regions in human adulthood. Seven electronic databases were searched for prospective controlled studies published up to April 2015. The quality of the selected studies was evaluated with the Cochrane Collaboration's tool for assessing the risk of bias. RevMan 5.3 software was applied for data analysis. Finally, 14 studies with 631 participants were identified. Meta-analysis revealed that aerobic exercise could significantly increase right hippocampal volume (SMD = 0.26, 95% CI 0.01-0.51, p = 0.04, I = 7%, 4 studies), and trends of similar effects were observed in the total (SMD = 0.12, 95% CI -0.17 to 0.41, p = 0.43, I = 0%, 5 studies), left (SMD = 0.12, 95% CI -0.13 to 0.37, p = 0.33, I = 14%, 4 studies), left anterior (SMD = 0.12, 95% CI -0.16 to 0.40, p = 0.41, I = 74%, 2 studies) and right anterior (SMD = 0.10, 95% CI -0.17 to 0.38, p = 0.46, I = 76%, 4 studies) hippocampal volumes compared to the no-exercise interventions. A few studies reported that relative to no-exercise interventions, aerobic exercise could significantly decrease the atrophy of the medial temporal lobe, slow the anterior cingulate cortex (ACC) volume loss, increase functional connectivity within the hippocampus and improve signal activation in the cingulate gyrus and ACC. The current review suggests that aerobic exercise may have positive effects on the right hippocampus and potentially beneficial effects on the overall and other parts of the hippocampus, the cingulate cortex and the medial temporal areas of the DMN. Moreover, aerobic exercise may increase functional connectivity or activation in the hippocampus, cingulate cortex and parahippocampal gyrus regions of the DMN. However, considering the quantity and limitations of the included studies, the conclusion could not be drawn so far. Additional randomized controlled trials (RCTs) with rigorous designs and longer intervention periods are needed in the future.
Topics: Brain; Brain Diseases; Exercise; Exercise Therapy; Humans; Nerve Net
PubMed: 27412353
DOI: 10.1080/00207454.2016.1212855 -
Frontiers in Aging Neuroscience 2023Mild cognitive impairment (MCI) depicts a transitory phase between healthy elderly and the onset of Alzheimer's disease (AD) with worsening cognitive impairment. Some...
BACKGROUND
Mild cognitive impairment (MCI) depicts a transitory phase between healthy elderly and the onset of Alzheimer's disease (AD) with worsening cognitive impairment. Some functional MRI (fMRI) research indicated that the frontoparietal network (FPN) could be an essential part of the pathophysiological mechanism of MCI. However, damaged FPN regions were not consistently reported, especially their interactions with other brain networks. We assessed the fMRI-specific anomalies of the FPN in MCI by analyzing brain regions with functional alterations.
METHODS
PubMed, Embase, and Web of Science were searched to screen neuroimaging studies exploring brain function alterations in the FPN in MCI using fMRI-related indexes, including the amplitude of low-frequency fluctuation, regional homogeneity, and functional connectivity. We integrated distinctive coordinates by activating likelihood estimation, visualizing abnormal functional regions, and concluding functional alterations of the FPN.
RESULTS
We selected 29 studies and found specific changes in some brain regions of the FPN. These included the bilateral dorsolateral prefrontal cortex, insula, precuneus cortex, anterior cingulate cortex, inferior parietal lobule, middle temporal gyrus, superior frontal gyrus, and parahippocampal gyrus. Any abnormal alterations in these regions depicted interactions between the FPN and other networks.
CONCLUSION
The study demonstrates specific fMRI neuroimaging alterations in brain regions of the FPN in MCI patients. This could provide a new perspective on identifying early-stage patients with targeted treatment programs.
SYSTEMATIC REVIEW REGISTRATION
https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023432042, identifier: CRD42023432042.
PubMed: 37448688
DOI: 10.3389/fnagi.2023.1165908 -
Neuroscience and Biobehavioral Reviews Feb 2012Structural neuroimaging studies of white matter volume (WMV) in Alzheimer's disease (AD) with voxel-based morphometry (VBM) have yielded variable findings. (Meta-Analysis)
Meta-Analysis Review
BACKGROUND
Structural neuroimaging studies of white matter volume (WMV) in Alzheimer's disease (AD) with voxel-based morphometry (VBM) have yielded variable findings.
METHODS
A systematic review of VBM studies of WMV of patients with AD and healthy control (HC) subjects indexed in PubMed, ISI Web of Science, and EMBASE from 1990 to June 2011 was conducted. Coordinates were extracted from clusters with significant difference in WMV between patients with AD and HC subjects. Meta-analysis was performed using Effect Size Signed Differential Mapping (ES-SDM).
RESULTS
Eight studies were enrolled, which included 227 patients with AD and 215 HC subjects. WMV reduction at 69 coordinates in AD and no WMV increase were found in the current meta-analysis. Significant reductions were observed in the left parahippocampal gyrus extending to the temporal white matter, the right temporal white matter extending to the parahippocampal gyrus and the posterior corpus callosum. The findings remain largely unchanged in the jackknife sensitivity analyses.
CONCLUSIONS
White matter atrophy was clearly identified in AD, mainly in bilateral structures close to memory formations such as the hippocampus, amygdala, and entorhinal cortex.
Topics: Alzheimer Disease; Brain; Brain Mapping; Databases, Bibliographic; Humans; Nerve Fibers, Myelinated; Neuroimaging
PubMed: 22192882
DOI: 10.1016/j.neubiorev.2011.12.001