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NeuroImage Sep 2021Humans use different spatial reference frames (allocentric or egocentric) to navigate successfully toward their destination in different spatial scale spaces... (Review)
Review
Humans use different spatial reference frames (allocentric or egocentric) to navigate successfully toward their destination in different spatial scale spaces (environmental or vista). However, it remains unclear how the brain represents different spatial scales and different spatial reference frames. Thus, we conducted an activation likelihood estimation (ALE) meta-analysis of 47 fMRI articles involving human spatial navigation. We found that both the environmental and vista spaces activated the parahippocampal place area (PPA), retrosplenial complex (RSC), and occipital place area in the right hemisphere. The environmental space showed stronger activation than the vista space in the occipital and frontal regions. No brain region exhibited stronger activation for the vista than the environmental space. The allocentric and egocentric reference frames activated the bilateral PPA and right RSC. The allocentric frame showed more stronger activations than the egocentric frame in the right culmen, left middle frontal gyrus, and precuneus. No brain region displayed stronger activation for the egocentric than the allocentric navigation. Our findings suggest that navigation in different spatial scale spaces can evoke specific and common brain regions, and that the brain regions representing spatial reference frames are not absolutely separated.
Topics: Environment; Humans; Nerve Net; Occipital Lobe; Parahippocampal Gyrus; Space Perception; Spatial Navigation
PubMed: 34129948
DOI: 10.1016/j.neuroimage.2021.118264 -
Human Brain Mapping Feb 2021Early course schizophrenia is associated with reduced gray matter. The specific structures affected first and how deficits impact symptoms and cognition remain...
Early course schizophrenia is associated with reduced gray matter. The specific structures affected first and how deficits impact symptoms and cognition remain unresolved. We used the Human Connectome Project multimodal parcellation (HCP-MMP) to precisely identify cortical areas and investigate thickness abnormalities in discovery and replication samples of first-episode schizophrenia spectrum individuals (FESz). In the discovery sample, T1w scans were acquired from 31 FESz and 31 matched healthy controls (HC). Thickness was calculated for 360 regions in Freesurfer. In the replication sample, high-resolution T1w, T2w, and BOLD-rest scans were acquired from 23 FESz and 32 HC and processed with HCP protocols. Thickness was calculated for regions significant in the discovery sample. After FDR correction (q < .05), left and right parahippocampal area 3 (PHA3) were significantly thinner in FESz. In the replication sample, bilateral PHA3 were again thinner in FESz (q < .05). Exploratory correlation analyses revealed left PHA3 was positively associated with hallucinations and right PHA3 was positively associated with processing speed, working memory, and verbal learning. The novel use of the HCP-MMP in two independent FESz samples revealed thinner bilateral PHA3, suggesting this byway between cortical and limbic processing is a critical site of pathology near the emergence of psychosis.
Topics: Adult; Female; Gray Matter; Humans; Magnetic Resonance Imaging; Male; Neuroimaging; Parahippocampal Gyrus; Psychotic Disorders; Schizophrenia; Young Adult
PubMed: 33219733
DOI: 10.1002/hbm.25256 -
Journal of Diabetes Investigation Oct 2021We aimed to examine the association between diabetes-related parameters and hippocampal and parahippocampal gyrus atrophy (HPGA) in patients with type 2 diabetes...
AIMS/INTRODUCTION
We aimed to examine the association between diabetes-related parameters and hippocampal and parahippocampal gyrus atrophy (HPGA) in patients with type 2 diabetes mellitus to elucidate the risk factors for HPGA, which is often accompanied by Alzheimer's disease.
MATERIALS AND METHODS
A total of 137 patients aged ≥50 years with type 2 diabetes mellitus (mean age 67.8 ± 9.8 years) underwent brain magnetic resonance imaging scans and comprehensive health examinations. We measured the volume of interest - a portion of the inner temporal lobe that includes the hippocampus, amygdala and entorhinal cortex (frontal part of the parahippocampal gyrus) - using the voxel-based specific regional analysis system for Alzheimer's disease in each patient. The diabetes-related parameters included glycated hemoglobin, fasting plasma glucose, C-peptide (CPR) index (serum CPR / fasting plasma glucose × 100) and duration of diabetes.
RESULTS
The mean glycated hemoglobin was 9.3 ± 2.2%, the median CPR index was 1.29 (interquartile range 0.85-1.74) and the median duration of diabetes was 10 years (interquartile range 3-20 years). The severity score of volume of interest atrophy was >1.0 in 36 patients. Using multivariate logistic regression analysis, we found that age (odds ratio 1.09, 95% confidence interval 1.02-1.15) and CPR index (odds ratio 0.451, 95% confidence interval 0.216-0.940) were significantly associated with HPGA.
CONCLUSIONS
Lower insulin secretion was significantly associated with HPGA in patients with type 2 diabetes mellitus. The results of this study support the hypothesis that insulin-signaling abnormalities are involved in the pathophysiology of Alzheimer's disease.
Topics: Aged; Cross-Sectional Studies; Diabetes Mellitus, Type 2; Female; Humans; Insulin Secretion; Male; Middle Aged; Parahippocampal Gyrus
PubMed: 33783982
DOI: 10.1111/jdi.13554 -
NeuroImage Apr 2022Risk-taking differs between humans, and is associated with the personality measures of impulsivity and sensation-seeking. To analyse the brain systems involved,...
Risk-taking differs between humans, and is associated with the personality measures of impulsivity and sensation-seeking. To analyse the brain systems involved, self-report risk-taking, resting state functional connectivity, and related behavioral measures were analyzed in 18,740 participants of both sexes from the UK Biobank. Functional connectivities of the medial orbitofrontal cortex, ventromedial prefrontal cortex (VMPFC), and the parahippocampal areas were significantly higher in the risk-taking group (p < 0.001, FDR corrected). The risk-taking measure was validated in that it was significantly associated with alcohol drinking amount (r = 0.08, p = 5.1×10), cannabis use (r = 0.12, p = 6.0×10), and anxious feelings (r = -0.12, p = 7.6×). The functional connectivity findings were cross-validated in two independent datasets. The higher functional connectivity of the medial orbitofrontal cortex and VMPFC included higher connectivity with the anterior cingulate cortex, which provides a route for these reward-related regions to have a greater influence on action in risk-taking individuals. In conclusion, the medial orbitofrontal cortex, which is involved in reward value and pleasure, was found to be related to risk-taking, which is associated with impulsivity. An implication is that risk-taking is driven by specific orbitofrontal cortex reward systems, and is different for different rewards which are represented differently in the brains of different individuals. This is an advance in understanding the bases and mechanisms of risk-taking in humans, given that the orbitofrontal cortex, VMPFC and anterior cingulate cortex are highly developed in humans, and that risk-taking can be reported in humans.
Topics: Adult; Aged; Connectome; Female; Gyrus Cinguli; Humans; Impulsive Behavior; Magnetic Resonance Imaging; Male; Middle Aged; Parahippocampal Gyrus; Prefrontal Cortex; Reward; Risk-Taking
PubMed: 35007715
DOI: 10.1016/j.neuroimage.2022.118893 -
Hippocampus Jan 2017The advent of high-resolution magnetic resonance imaging (MRI) has enabled in vivo research in a variety of populations and diseases on the structure and function of...
The advent of high-resolution magnetic resonance imaging (MRI) has enabled in vivo research in a variety of populations and diseases on the structure and function of hippocampal subfields and subdivisions of the parahippocampal gyrus. Because of the many extant and highly discrepant segmentation protocols, comparing results across studies is difficult. To overcome this barrier, the Hippocampal Subfields Group was formed as an international collaboration with the aim of developing a harmonized protocol for manual segmentation of hippocampal and parahippocampal subregions on high-resolution MRI. In this commentary we discuss the goals for this protocol and the associated key challenges involved in its development. These include differences among existing anatomical reference materials, striking the right balance between reliability of measurements and anatomical validity, and the development of a versatile protocol that can be adopted for the study of populations varying in age and health. The commentary outlines these key challenges, as well as the proposed solution of each, with concrete examples from our working plan. Finally, with two examples, we illustrate how the harmonized protocol, once completed, is expected to impact the field by producing measurements that are quantitatively comparable across labs and by facilitating the synthesis of findings across different studies. © 2016 Wiley Periodicals, Inc.
Topics: Hippocampus; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Parahippocampal Gyrus; Pattern Recognition, Automated
PubMed: 27862600
DOI: 10.1002/hipo.22671 -
Neuroscience Jun 2008The posterior parahippocampal gyrus (PPHG) of the non-human primate brain has a distinct dual role in cortical neural systems. On the one hand, it is a critical link in...
The posterior parahippocampal gyrus (PPHG) of the non-human primate brain has a distinct dual role in cortical neural systems. On the one hand, it is a critical link in providing the entorhinal cortex and hippocampal formation with cortical input, while on the other hand it receives output from these structures and projects widely by disseminating the medial temporal lobe output to the cortex. Layer III of TF and TH areas largely mediate the former (input) while layer V mediates the latter (output). We have examined areas TF and TH in the normal human brain and in Alzheimer's disease (AD) using pathological stains (Nissl, Thioflavin S) and phenotype specific stains non-phosphorylated neurofilament protein (SMI32) and parvalbumin (PV). Seven clinically and pathologically confirmed AD cases have been studied along with six age-compatible normal cases. Our observations reveal that neurofibrillary tangles (NFTs) heavily invest the area TF and TH neurons that form layers III and V. In both cortical areas, the large pyramids that form layer V contain a greater number of NFTs. These changes, and possibly, pyramidal cell loss, greatly alter the cytoarchitectural picture and diminish SMI32 staining patterns. Layer III of area TH loses the majority of SMI32 immunoreactivity, whereas this change is more conspicuous in layer V of area TF. PV-staining in both areas is largely unaffected. Normal cases contained no evidence of pathology or altered cytoarchitecture. These observations reveal a further disruption of memory-related temporal neural systems in AD where pathology selectively alters both the input to the hippocampal formation and its output to the cortex.
Topics: Aged; Aged, 80 and over; Alzheimer Disease; Benzothiazoles; Cerebral Cortex; Female; Humans; Immunohistochemistry; Male; Neurofibrillary Tangles; Neurofilament Proteins; Parahippocampal Gyrus; Parvalbumins; Thiazoles
PubMed: 18486350
DOI: 10.1016/j.neuroscience.2008.03.077 -
Social Cognitive and Affective... Mar 2018Proactive interference (PI) is the tendency for information learned earlier to interfere with more recently learned information. In the present study, we induced PI by...
Proactive interference (PI) is the tendency for information learned earlier to interfere with more recently learned information. In the present study, we induced PI by presenting items from the same category over several trials. This results in a build-up of PI and reduces the discriminability of the items in each subsequent trial. We introduced emotional (e.g. disgust) and neutral (e.g. furniture) categories and examined how increasing levels of PI affected performance for both stimulus types. Participants were scanned using functional magnetic resonance imaging (fMRI) performing a 5-item probe recognition task. We modeled responses and corresponding response times with a hierarchical diffusion model. Results showed that PI effects on latent processes (i.e. reduced drift rate) were similar for both stimulus types, but the effect of PI on drift rate was less pronounced PI for emotional compared to neutral stimuli. The decline in the drift rate was accompanied by an increase in neural activation in parahippocampal regions and this relationship was more strongly observed for neutral stimuli compared to emotional stimuli.
Topics: Adult; Amygdala; Discrimination, Psychological; Emotions; Female; Humans; Image Processing, Computer-Assisted; Magnetic Resonance Imaging; Male; Memory; Memory, Short-Term; Mental Recall; Models, Psychological; Parahippocampal Gyrus; Photic Stimulation; Prefrontal Cortex; Proactive Inhibition; Recognition, Psychology
PubMed: 29272535
DOI: 10.1093/scan/nsx145 -
Journal of Behavioral Addictions Apr 2020Understanding the neural mechanisms underlying Internet gaming disorder (IGD) is essential for the condition's diagnosis and treatment. Nevertheless, the pathological...
OBJECTIVES
Understanding the neural mechanisms underlying Internet gaming disorder (IGD) is essential for the condition's diagnosis and treatment. Nevertheless, the pathological mechanisms of IGD remain elusive at present. Hence, we employed multi-voxel pattern analysis (MVPA) and spectral dynamic causal modeling (spDCM) to explore this issue.
METHODS
Resting-state fMRI data were collected from 103 IGD subjects (male = 57) and 99 well-matched recreational game users (RGUs, male = 51). Regional homogeneity was calculated as the feature for MVPA based on the support vector machine (SVM) with leave-one- out cross-validation. Mean time series data extracted from the brain regions in accordance with the MVPA results were used for further spDCM analysis.
RESULTS
Results display a high accuracy of 82.67% (sensitivity of 83.50% and specificity of 81.82%) in the classification of the two groups. The most discriminative brain regions that contributed to the classification were the bilateral parahippocampal gyrus (PG), right anterior cingulate cortex (ACC), and middle frontal gyrus (MFG). Significant correlations were found between addiction severity (IAT and DSM scores) and the ReHo values of the brain regions that contributed to the classification. Moreover, the results of spDCM showed that compared with RGU, IGD showed decreased effective connectivity from the left PG to the right MFG and from the right PG to the ACC and decreased self-connection in the right PG.
CONCLUSIONS
These results show that the weakening of the PG and its connection with the prefrontal cortex, including the ACC and MFG, may be an underlying mechanism of IGD.
Topics: Adult; Connectome; Female; Gyrus Cinguli; Humans; Internet Addiction Disorder; Magnetic Resonance Imaging; Male; Parahippocampal Gyrus; Prefrontal Cortex; Sensitivity and Specificity; Support Vector Machine; Video Games; Young Adult
PubMed: 32359234
DOI: 10.1556/2006.2020.00012 -
Brain Structure & Function Jan 2011The main aim of the present study was to compare volume differences in the hippocampus and parahippocampal gyrus as biomarkers of Alzheimer's disease (AD). Based on the...
The main aim of the present study was to compare volume differences in the hippocampus and parahippocampal gyrus as biomarkers of Alzheimer's disease (AD). Based on the previous findings, we hypothesized that there would be significant volume differences between cases of healthy aging, amnestic mild cognitive impairment (aMCI), and mild AD. Furthermore, we hypothesized that there would be larger volume differences in the parahippocampal gyrus than in the hippocampus. In addition, we investigated differences between the anterior, middle, and posterior parts of both structures. We studied three groups of participants: 18 healthy participants without memory decline, 18 patients with aMCI, and 18 patients with mild AD. 3 T T1-weighted MRI scans were acquired and gray matter volumes of the anterior, middle, and posterior parts of both the hippocampus and parahippocampal gyrus were measured using a manual tracing approach. Volumes of both the hippocampus and parahippocampal gyrus were significantly different between the groups in the following order: healthy>aMCI>AD. Volume differences between the groups were relatively larger in the parahippocampal gyrus than in the hippocampus, in particular, when we compared healthy with aMCI. No substantial differences were found between the anterior, middle, and posterior parts of both structures. Our results suggest that parahippocampal volume discriminates better than hippocampal volume between cases of healthy aging, aMCI, and mild AD, in particular, in the early phase of the disease. The present results stress the importance of parahippocampal atrophy as an early biomarker of AD.
Topics: Aged; Alzheimer Disease; Atrophy; Biomarkers; Brain Mapping; Hippocampus; Humans; Magnetic Resonance Imaging; Male; Memory Disorders; Middle Aged; Parahippocampal Gyrus
PubMed: 20957494
DOI: 10.1007/s00429-010-0283-8 -
Cerebral Cortex (New York, N.Y. : 1991) May 2020The neural basis of memory is highly distributed, but the thalamus is known to play a particularly critical role. However, exactly how the different thalamic nuclei...
The neural basis of memory is highly distributed, but the thalamus is known to play a particularly critical role. However, exactly how the different thalamic nuclei contribute to different kinds of memory is unclear. Moreover, whether thalamic connectivity with the medial temporal lobe (MTL), arguably the most fundamental memory structure, is critical for memory remains unknown. We explore these questions using an fMRI recognition memory paradigm that taps familiarity and recollection (i.e., the two types of memory that support recognition) for objects, faces, and scenes. We show that the mediodorsal thalamus (MDt) plays a material-general role in familiarity, while the anterior thalamus plays a material-general role in recollection. Material-specific regions were found for scene familiarity (ventral posteromedial and pulvinar thalamic nuclei) and face familiarity (left ventrolateral thalamus). Critically, increased functional connectivity between the MDt and the parahippocampal (PHC) and perirhinal cortices (PRC) of the MTL underpinned increases in reported familiarity confidence. These findings suggest that familiarity signals are generated through the dynamic interaction of functionally connected MTL-thalamic structures.
Topics: Adult; Anterior Thalamic Nuclei; Female; Functional Neuroimaging; Humans; Magnetic Resonance Imaging; Male; Mediodorsal Thalamic Nucleus; Mental Recall; Neural Pathways; Parahippocampal Gyrus; Perirhinal Cortex; Pulvinar; Recognition, Psychology; Temporal Lobe; Thalamus; Ventral Thalamic Nuclei; Young Adult
PubMed: 31989161
DOI: 10.1093/cercor/bhz345