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Cerebral Cortex (New York, N.Y. : 1991) Dec 2023In trace fear conditioning, the prelimbic cortex exhibits persistent activity during the interval between the conditioned and unconditioned stimuli, which maintains a...
In trace fear conditioning, the prelimbic cortex exhibits persistent activity during the interval between the conditioned and unconditioned stimuli, which maintains a conditioned stimulus representation. Regions cooperating for this function or encoding the conditioned stimulus before the interval could send inputs to the prelimbic cortex, supporting learning. The basolateral amygdala has conditioned stimulus- and unconditioned stimulus-responsive neurons, convergently activated. The prelimbic cortex could directly project to the basolateral amygdala to associate the transient memory of the conditioned stimulus with the unconditioned stimulus. We investigated the neuronal circuit supporting temporal associations using contextual fear conditioning with a 5-s interval, in which 5 s separates the contextual conditioned stimulus from the unconditioned stimulus. Injecting retrobeads, we quantified c-Fos in prelimbic cortex- or basolateral amygdala-projecting neurons from 9 regions after contextual fear conditioning with a 5-s interval or contextual fear conditioning, in which the conditioned and unconditioned stimuli overlap. The contextual fear conditioning with a 5-s interval activated ventral CA1 and perirhinal cortex neurons projecting to the prelimbic cortex and prelimbic cortex neurons projecting to basolateral amygdala. Both fear conditioning activated ventral CA1 and lateral entorhinal cortex neurons projecting to basolateral amygdala and basolateral amygdala neurons projecting to prelimbic cortex. The perirhinal cortex → prelimbic cortex and ventral CA1 → prelimbic cortex connections are the first identified prelimbic cortex afferent projections participating in temporal associations. These results help to understand time-linked memories, a process required in episodic and working memories.
Topics: Basolateral Nuclear Complex; Prefrontal Cortex; Perirhinal Cortex; Learning; Conditioning, Classical
PubMed: 37823340
DOI: 10.1093/cercor/bhad375 -
Journal of the American Geriatrics... Sep 2022Although the prevalence of gait disturbance is increasing with population aging, our understanding of its underlying neural basis is still limited. The precise brain...
BACKGROUND
Although the prevalence of gait disturbance is increasing with population aging, our understanding of its underlying neural basis is still limited. The precise brain regions linked to specific gait domains have not been well defined. In this study, we aim to investigate the associations of cortical thickness and different gait domains, and to explore whether these associations could be explained by cerebral small vessel disease.
METHODS
A total of 707 community-dwelling participants from the Taizhou Imaging Study (mean age: 60.2 ± 3.0 years, 57.4% female) were involved. All participants underwent brain MRI and gait assessment. We obtained quantitative gait parameters using wearable devices and then summarized them into three independent gait domains through factor analysis. Cortical thickness was analyzed and visualized using FreeSurfer and Surfstat.
RESULTS
Three independent domains (pace, rhythm, and variability) were summarized from 12 gait parameters. Among gait domains, poorer pace was associated with the thinner cortical thickness of multiple regions, which included areas related with motor function (e.g., the primary motor cortex, premotor cortex, and supplementary motor area), sensory function (e.g., the postcentral gyrus and paracentral lobule), visuospatial attention (e.g., the lateral occipital cortex and lingual gyrus), and identification and cognition (e.g., the fusiform gyrus and entorhinal cortex). Such a relationship was only slightly attenuated after adjustment for cerebrovascular risk factors and cerebral small vessel disease. No statistically significant association was found between cortical thickness and the rhythm or variability domains.
CONCLUSIONS
Poorer pace is independently associated with thinner cortical thickness in areas important for motor, sensory, cognitive function, and visuospatial attention. Our study emphasizes the importance of cortical thickness in gait control and adds value in investigating neural mechanisms of gait.
Topics: Aged; Cerebral Cortex; Cerebral Small Vessel Diseases; Cognition; Cross-Sectional Studies; Female; Gait; Humans; Magnetic Resonance Imaging; Male
PubMed: 35510857
DOI: 10.1111/jgs.17840 -
European Journal of Orthopaedic Surgery... May 2023A coherent measurement approach for sagittal alignment of the distal femur after fracture reduction or distal femur osteotomies is not available. The present study aims...
BACKGROUND
A coherent measurement approach for sagittal alignment of the distal femur after fracture reduction or distal femur osteotomies is not available. The present study aims to introduce a new method using Blumensaat's line and tangent lines to the femoral cortexes to determine the sagittal alignment of the distal femur.
METHODS
113 patients who had true lateral knee radiographs were included. All of the radiographs were evaluated by one fellowship-trained knee surgeon and one radiologist using the PACS system. The Blumensaat's line was determined on the true lateral knee radiographs. Then, three long lines were drawn on the distal third of the femoral shaft. The first line is tangent to the anterior cortex of the femur, the second line is along with the anatomical axis of the femur, and the third line is tangent to the posterior cortex of the femur. The angles between Blumensaat's line and these lines were measured. Intraclass Correlation Coefficient (ICC) was used to measure the strength of inter-and intra-rater agreement.
RESULTS
The mean angle between the Blumensaat's line and the anatomical axis of the femur was 35.4 ± 3°. The mean angle between the Blumensaat's line and the line tangent to the anterior femoral cortex and the line tangent to the posterior femoral cortex were 34.5 ± 3° and 35.2 ± 3°, respectively. Excellent inter-and intra-rater reliabilities were observed between the measurements (ICC = 0.96 and ICC = 0.98, respectively). The angle between the Blumensaat's line and the line tangent to the posterior femoral cortex was significantly higher in participants aged < 38 years (p = 0.049). No other significant association was found between the angles and demographic characteristics of the patients.
CONCLUSIONS
The expected mean angles between the Blumensaat's line and the distal femur were 34.3 to 35.4 degrees. This finding could be useful to determine the normal sagittal alignment of the distal femur.
LEVEL OF EVIDENCE
II.
Topics: Humans; Femur; Knee Joint; Lower Extremity; Radiography; Osteotomy
PubMed: 35377070
DOI: 10.1007/s00590-022-03212-3 -
Cytoskeleton (Hoboken, N.J.) Mar 2024The cell's ability to change shape is a central feature in many cellular processes, including cytokinesis, motility, migration, and tissue formation. The cell constructs... (Review)
Review
The cell's ability to change shape is a central feature in many cellular processes, including cytokinesis, motility, migration, and tissue formation. The cell constructs a network of contractile proteins underneath the cell membrane to form the cortex, and the reorganization of these components directly contributes to cellular shape changes. The desire to mimic these cell shape changes to aid in the creation of a synthetic cell has been increasing. Therefore, membrane-based reconstitution experiments have flourished, furthering our understanding of the minimal components the cell uses throughout these processes. Although biochemical approaches increased our understanding of actin, myosin II, and actin-associated proteins, using membrane-based reconstituted systems has further expanded our understanding of actin structures and functions because membrane-cortex interactions can be analyzed. In this review, we highlight the recent developments in membrane-based reconstitution techniques. We examine the current findings on the minimal components needed to recapitulate distinct actin structures and functions and how they relate to the cortex's impact on cellular mechanical properties. We also explore how co-processing of computational models with wet-lab experiments enhances our understanding of these properties. Finally, we emphasize the benefits and challenges inherent to membrane-based, reconstitution assays, ranging from the advantage of precise control over the system to the difficulty of integrating these findings into the complex cellular environment.
PubMed: 38520148
DOI: 10.1002/cm.21855 -
JCPP Advances Dec 2021Vascular-brain associations are well established in adults but neglected in youth and psychiatric populations, who are at greater cardiovascular risk. We therefore...
OBJECTIVES
Vascular-brain associations are well established in adults but neglected in youth and psychiatric populations, who are at greater cardiovascular risk. We therefore examined the association of retinal vascular caliber with regional brain structure in adolescents with and without bipolar disorder (BD).
METHODS
One hundred and three adolescents ( = 51 BD, = 52 healthy control [HC]) completed retinal fundus imaging, yielding arteriolar and venular diameters, followed by T1-weighted 3-Tesla MRI. Region of interest (ROI) analyses examined ventrolateral prefrontal cortex (vlPFC) and ventromedial prefrontal cortex (vmPFC), anterior cingulate cortex (ACC), amygdala, and hippocampus, complemented by vertex-wise analyses. Linear regression assessed the association between retinal measures and brain structure, adjusting for covariates including age, sex, BMI, and intracranial volume (ICV).
RESULTS
In the overall sample, arteriolar caliber was negatively associated with ACC volume ( = -0.20, = .046) and surface area ( = -0.19, = .049). There were no other significant ROI findings. Vertex-wise analyses detected several significant positive bilateral associations of arteriovenous ratio (AVR) with volume and surface area in regions including rostral middle frontal gyrus (left = .001; right = .006), isthmus cingulate cortex (left and right < .001), and left precuneus ( < .001). Significant negative associations were also observed for AVR ( = .03) and arteriolar caliber ( = .01), including a cluster encompassing the left rostral middle frontal gyrus and orbitofrontal cortical thickness. In the sole retinal-by-diagnosis interaction, greater AVR was more strongly associated with lower volume in the left middle temporal and fusiform gyri in BD versus HC ( = .004).
CONCLUSION
This study provides evidence that vascular-brain associations are already evident in adolescence, suggesting that optimizing cardiovascular health may benefit the brain. This may be particularly relevant in BD and other brain disorders. Future research focusing on subpopulations where vascular-brain associations may be especially strong, for whom vascular-related interventions may be most indicated, is warranted.
PubMed: 37431401
DOI: 10.1002/jcv2.12029 -
Psychiatry Research. Neuroimaging Dec 2023The structural neural correlates underlying youth nonsuicidal self-injury (NSSI) warrant further exploration. Few studies have explored the association between NSSI and...
The structural neural correlates underlying youth nonsuicidal self-injury (NSSI) warrant further exploration. Few studies have explored the association between NSSI and brain structure in adolescence, and no studies have investigated differences in the relation between age and brain structure in youth with NSSI. This preliminary investigation examined associations between NSSI history, age, and cortical structure using magnetic resonance imaging in adolescent girls (=100, =13.4 years) at increased risk for psychopathology. We conducted whole-brain analyses to investigate the associations between age and cortical structure, NSSI history and cortical structure, and NSSI history as a moderator of the association between age and cortical structure. Results suggested that age was associated with less cortical thickness and surface area in the left and right prefrontal, temporal, and parietal cortex. NSSI history was associated with less left insula and left inferior parietal cortex cortical surface area. Among adolescents with NSSI history, older age predicted greater left inferior parietal cortex surface area and was not associated with left precentral cortex surface area. Among adolescents without NSSI history, older age predicted smaller surface areas as expected with the typical trajectory of neurodevelopment. Overall, our results suggest differences in cortical surface area development in adolescents with NSSI history.
Topics: Female; Humans; Adolescent; Self-Injurious Behavior; Brain; Adolescent Behavior; Cerebral Cortex; Magnetic Resonance Imaging
PubMed: 38456014
DOI: 10.1016/j.pscychresns.2023.111725 -
Frontiers in Neurology 2024Dysregulation of circulating metabolites may affect brain function and cognition, associated with alterations in the cerebral cortex architecture. However, the exact...
BACKGROUND
Dysregulation of circulating metabolites may affect brain function and cognition, associated with alterations in the cerebral cortex architecture. However, the exact cause remains unclear. This study aimed to determine the causal effect of circulating metabolites on the cerebral cortex architecture.
METHODS
This study utilized retrieved data from genome-wide association studies to investigate the relationship between blood metabolites and cortical architecture. A total of 1,091 metabolites and 309 metabolite ratios were used for exposure. The brain cortex surface area and cortex thickness were selected as the primary outcomes in this study. In this study, the inverse variance weighting method was used as the main analytical method, complemented by sensitivity analyses that were more robust to pleiotropy. Furthermore, metabolic pathway analysis was performed via MetaboAnalyst 6.0. Finally, reverse Mendelian randomization (MR) analysis was conducted to assess the potential for reverse causation.
RESULTS
After correcting for the false discovery rate (FDR), we identified 37 metabolites and 9 metabolite ratios that showed significant causal associations with cortical structures. Among these, Oxalate was found to be most strongly associated with cortical surface area (: 2387.532, 95% CI 756.570-4018.495, = 0.037), while Tyrosine was most correlated with cortical thickness (: -0.015, 95% CI -0.005 to -0.025, = 0.025). Furthermore, pathway analysis based on metabolites identified six significant metabolic pathways associated with cortical structures and 13 significant metabolic pathways based on metabolite ratios.
CONCLUSION
The identified metabolites and relevant metabolic pathways reveal potential therapeutic pathways for reducing the risk of neurodegenerative diseases. These findings will help guide health policies and clinical practice in treating neurodegenerative diseases.
PubMed: 38784905
DOI: 10.3389/fneur.2024.1386844 -
Scientific Reports Feb 2023The aim was to investigate the association of parental education at birth with cognitive ability in childhood and young adulthood and determine, whether functional...
The aim was to investigate the association of parental education at birth with cognitive ability in childhood and young adulthood and determine, whether functional connectivity of the salience network underlies this association. We studied participants of the Czech arm of the European Longitudinal Study of Pregnancy and Childhood who underwent assessment of their cognitive ability at age 8 (Wechsler Intelligence Scale for Children) and 28/29 years (Wechsler Adult Intelligence Scale) and measurement with resting state functional MRI at age 23/24. We estimated the associations of parental education with cognitive ability and functional connectivity between the seeds in the salience network and other voxels in the brain. We found that lower education of both mothers and fathers was associated with lower verbal IQ, performance IQ and full-scale IQ of the offspring at age 8. Only mother´s education was associated with performance IQ at age 28/29. Lower mother´s education correlated with greater functional connectivity between the right rostral prefrontal cortex and a cluster of voxels in the occipital cortex, which, in turn, was associated with lower performance IQ at age 28/29. We conclude that the impact of parental education, particularly father´s, on offspring´s cognitive ability weakens during the lifecourse. Functional connectivity between the right rostral prefrontal cortex and occipital cortex may be a biomarker underlying the transmission of mother´s education on performance IQ of their offspring.
Topics: Child; Pregnancy; Infant, Newborn; Adult; Female; Humans; Young Adult; Longitudinal Studies; Intelligence Tests; Educational Status; Cognition; Parents
PubMed: 36797291
DOI: 10.1038/s41598-023-29508-w -
Proceedings of the Japan Academy.... 2022The cerebral cortex performs its computations with many six-layered fundamental units, collectively spreading along the cortical sheet. What is the local network... (Review)
Review
The cerebral cortex performs its computations with many six-layered fundamental units, collectively spreading along the cortical sheet. What is the local network structure and the operating dynamics of such a fundamental unit? Previous investigations of primary sensory areas revealed a classic "canonical" circuit model, leading to an expectation of similar circuit organization and dynamics throughout the cortex. This review clarifies the different circuit dynamics at play in the higher association cortex of primates that implements computation for high-level cognition such as memory and attention. Instead of feedforward processing of response selectivity through Layers 4 to 2/3 that the classic canonical circuit stipulates, memory recall in primates occurs in Layer 5/6 with local backward projection to Layer 2/3, after which the retrieved information is sent back from Layer 6 to lower-level cortical areas for further retrieval of nested associations of target attributes. In this review, a novel "dynamic multimode module (D3M)" in the primate association cortex is proposed, as a new "canonical" circuit model performing this operation.
Topics: Animals; Cerebral Cortex; Memory; Primates
PubMed: 35283409
DOI: 10.2183/pjab.98.007