A data-driven functional mapping of the anterior temporal lobes

Journal of Neuroscience, Journal Year: 2021, Volume and Issue: unknown, P. JN - 21

Published: June 3, 2021

Although the anterior temporal lobe (ATL) comprises several anatomic and functional subdivisions, it is often reduced to a homogeneous theoretical entity, such as domain-general convergence zone, or "hub," for semantic information. Methodological limitations are largely blame imprecise mapping of function structure in ATL. There two major obstacles using fMRI identify precise organization ATL: difficult choice stimuli tasks activate, dissociate, specific regions within ATL; poor signal quality because magnetic field distortions near sinuses. To circumvent these difficulties, we developed data-driven parcellation routine resting-state data (24 females, 64 males) acquired sequence that was optimized enhance Focusing on patterns connectivity between each ATL voxel rest brain, found at least 34 distinct parcels arranged into bands along lateral ventral cortical surfaces, extending from posterior lobes poles. In addition, region fusiform gyrus, most cited location hub, be part domain-specific network associated with face social processing, rather than hub. These findings offer fine-grained map an initial step toward more language describe locations responses this heterogeneous human cortex. SIGNIFICANCE STATEMENT The role aspects contentious issue. While likely different subserve unique cognitive functions, studies revert vaguely referring particular "the ATL," and, thus, anatomy remains unclear. We used brain reveal organized three-level hierarchy. results provide detailed can guide future research how support diverse functions.

Language: Английский

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Women’s Brain Health: Midlife Ovarian Removal Affects Associative Memory

Molecular Neurobiology, Journal Year: 2023, Volume and Issue: 60(11), P. 6145 - 6159

Published: July 10, 2023

Women with early bilateral salpingo-oophorectomy (BSO; removal of ovaries and fallopian tubes) have greater Alzheimer's disease (AD) risk than women in spontaneous/natural menopause (SM), but biomarkers this are not well-characterized. Considering associative memory deficits may presage preclinical AD, we wondered if one the earliest changes might be whether younger BSO had similar to those observed SM. (with without 17β-estradiol replacement therapy (ERT)), their age-matched premenopausal controls (AMC), older SM completed a functional magnetic resonance imaging face-name task shown predict AD. Brain activation during encoding was compared between groups: AMC (n=25), no ERT n=15), BSO+ERT (n=16), hormone (n=16). Region-of-interest analyses revealed did contribute group differences. higher hippocampal This correlated positively urinary metabolite levels 17β-estradiol. Multivariate partial least squares showed different network-level pattern Thus, despite being approximately 10 years younger, brain function SM, suggesting loss lead an altered phenotype which could influence late-life AD risk, making potential biomarker for midlife increased risk. Despite similarities activation, groups opposite within-hippocampus connectivity, type is important consideration when assessing function.

Language: Английский

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Aging and Alzheimer’s disease have dissociable effects on local and regional medial temporal lobe connectivity

Brain Communications, Journal Year: 2023, Volume and Issue: 5(5)

Published: Jan. 1, 2023

Abstract Functional disruption of the medial temporal lobe-dependent networks is thought to underlie episodic memory deficits in aging and Alzheimer’s disease. Previous studies revealed that anterior lobe more vulnerable pathological neurodegenerative processes In contrast, cognitive structural imaging literature indicates posterior, as opposed anterior, vulnerability normal aging. However, extent which aging-related relate functional brain poorly understood. To address this knowledge gap, we examined connectivity alterations its immediate neighbourhood—the Anterior-Temporal Posterior-Medial networks—in agers, individuals with preclinical disease patients Mild Cognitive Impairment or mild dementia due network perirhinal cortex, particular, observed an inverted ‘U-shaped’ relationship between stage. According our results, phase characterized by increased cortex other regions lobe, well one-hop neighbours system. This effect no longer present symptomatic Instead, displayed reduced hippocampal within hypoconnectivity For aging, results led three main conclusions: (i) intra-network both declines age; (ii) posterior segments become increasingly decoupled from each advancing (iii) subregions especially parahippocampal are age-associated loss function than their counterparts. Together, current highlight evolving dysfunction indicate different neurobiological mechanisms versus

Language: Английский

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Cognitive enhancement: Effects of methylphenidate, modafinil, and caffeine on latent memory and resting state functional connectivity in healthy adults

Human Brain Mapping, Journal Year: 2022, Volume and Issue: 43(14), P. 4225 - 4238

Published: June 7, 2022

Abstract Stimulants like methylphenidate, modafinil, and caffeine have repeatedly shown to enhance cognitive processes such as attention memory. However, brain‐functional mechanisms underlying enhancing effects of stimulants are still poorly characterized. Here, we utilized behavioral resting‐state fMRI data from a double‐blind randomized placebocontrolled study in 48 healthy male adults. The results show that performance different memory tasks is enhanced, functional connectivity (FC) specifically between the frontoparietal network (FPN) default mode (DMN) modulated by comparison placebo. Decreased negative right prefrontal medial parietal but also temporal lobe visual brain regions predicted stimulant‐induced latent enhancement. We discuss dopamine's role well its ability modulate FC large‐scale neural networks (e.g., FPN DMN) potential enhancement mechanism.

Language: Английский

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The Human Cerebello-Hippocampal Circuit Across Adulthood

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 18, 2025

Abstract Direct communication between the hippocampus and cerebellum has been shown via coactivation synchronized neuronal oscillations in animal models. Further, this novel cerebello-hippocampal circuit may be impacted by sex steroid hormones. The are dense with estradiol progesterone receptors relative to other brain regions. Females experience up a 90% decrease ovarian production after menopausal transition. Postmenopausal women show lower cerebello-cortical intracerebellar FC compared reproductive aged females. Sex hormones established modulators of both memory function synaptic organization non-human studies. However, investigation (CB-HP) limited studies small homogeneous samples young adults as it relates spatial navigation. Here, we investigate CB-HP 138 adult humans (53% female) from 35-86 years age, define its patterns, associations behavior, hormone levels, differences therein. We robust patterns CB HP sample. predicted found negative relationships age FC. As expected, levels exhibited positive CB-HP. higher progesterone. provide first characterization across middle older adulthood demonstrate that connectivity is sensitive levels. This work provides clear mapping human serves foundation for future neurological psychiatric diseases.

Language: Английский

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Intrinsic functional connectivity of right dorsolateral prefrontal cortex and hippocampus subregions relates to emotional and sensory-perceptual properties of intrusive trauma memories

Biological Psychiatry Cognitive Neuroscience and Neuroimaging, Journal Year: 2025, Volume and Issue: unknown

Published: March 1, 2025

Language: Английский

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Two long-axis dimensions of hippocampal-cortical integration support memory function across the adult lifespan

eLife, Journal Year: 2025, Volume and Issue: 13

Published: March 20, 2025

The hippocampus is a complex structure critically involved in numerous behavior-regulating systems. In young adults, multiple overlapping spatial modes along its longitudinal and transverse axes describe the organization of functional integration with neocortex, extending traditional framework emphasizing differences between sharply segregated hippocampal subregions. Yet, it remains unknown whether these (i.e. gradients) persist across adult human lifespan, relate to memory molecular markers associated brain function cognition. two independent samples, we demonstrate that principal anteroposterior second-order, mid-to-anterior/posterior neocortical connectivity, representing distinct dimensions macroscale cortical organization, manifest lifespan. Specifically, individual topography second-order gradient predicted episodic mirrored dopamine D1 receptor distribution, capturing shared organization. Older age was less transitions gradients increased homogeneity). Importantly, youth-like profile preserved – age-related dedifferentiation as marker cognitive decline. Our results underscore critical role mapping multidimensional understanding neural circuits support

Language: Английский

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Effects of Early Midlife Ovarian Removal on Medial Temporal Lobe Gray Matter Volume and Recognition Memory

Hippocampus, Journal Year: 2025, Volume and Issue: 35(3)

Published: March 29, 2025

Early midlife bilateral salpingo-oophorectomy (BSO) is associated with greater Alzheimer's disease risk compared to spontaneous/natural menopause. Previously, we found that participants BSO had lower volume in the hippocampal dentate gyrus and cornu ammonis 2/3 composite subfield (DG-CA2/3). We sought extend those findings by assessing whether affected volumes along anteroposterior axis, anterolateral entorhinal cortex, perirhinal cortex subregions (Brodmann area (BA) 35 36). also correlated key demographic wellbeing-related factors (age, depressive mood, education), hormone therapy characteristics, recognition memory performance. (with without 17β-estradiol (ET)) age-matched control intact ovaries (AMC) completed high-resolution T2-weighted structural magnetic resonance imaging (MRI). Medial temporal lobe Remember-Know task performance were between groups-BSO (n = 23), + ET 28), AMC 34) using univariate analyses. Multivariate Partial Least Squares (PLS) analyses used examine how related factors, as well characteristics. Relative ET, posterior DG-CA2/3 but BA 36 volumes. Compared age, education, was strongest positive predictor of negative For negatively duration positively concurrent progestogen therapy. AMC, groups ET) relied more on familiarity than recollection for successful memory. may have distinct effects medial volumes, potential implications processes risk.

Language: Английский

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Anterior vs Posterior Hippocampal Subfields in an Extended Psychosis Phenotype of Multidimensional Schizotypy in a Nonclinical Sample

Schizophrenia Bulletin, Journal Year: 2020, Volume and Issue: 47(1), P. 207 - 218

Published: July 2, 2020

Numerous studies have implicated involvement of the hippocampus in etiology and expression schizophrenia-spectrum psychopathology, reduced hippocampal volume is one most robust brain abnormalities reported schizophrenia. Recent indicate that early stages schizophrenia are specifically characterized by reductions anterior volume; however, not examined subclinical schizotypy. The present study was first to examine associations positive, negative, disorganized schizotypy dimensions with subfield volumes a large sample (n = 195) nonclinically ascertained young adults, phenotyped using Multidimensional Schizotypy Scale (MSS). Hippocampal subfields were analyzed from high-resolution 3 Tesla structural magnetic resonance imaging scans testing anatomical models, including vs posterior regions cornu ammonis (CA), dentate gyrus (DG), subiculum separately for left right hemispheres. We demonstrate differential spatial effects across segments different risk phenotype. interaction negative robustly predicted hemisphere volumetric total hippocampus, CA DG, largest seen participants high These findings extend previous psychosis together behavioral hippocampal-related memory impairments provide basis dimensional neurobiological model risk. Subtle may be prevalent prior onset detectable prodromal clinical symptoms play role development such conditions.

Language: Английский

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Age-related differences in encoding-retrieval similarity and their relationship to false memory

Neurobiology of Aging, Journal Year: 2022, Volume and Issue: 113, P. 15 - 27

Published: Feb. 5, 2022

Language: Английский

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