Default Mode Network Segregation Decreases in Healthy Brain Aging DOI
Abhijot S Sidhu,

Talal H. Shahid,

Kauê Tartarotti Nepomuceno Duarte

et al.

Published: Nov. 15, 2023

The default mode network (DMN) constitutes a cluster of interconnected brain regions engaged in internal cognitive processes, such as interoception, memory recall, and self-referential thinking. DMN is task-negative network, displaying increased activity during rest but reduced tasks. Resting-state functional magnetic resonance imaging (rs-MRI) examines this nature by tracking low-frequency fluctuations the blood oxygenation level-dependent signal an indirect marker for changes activity. Many cross-sectional studies have focused on understanding organization healthy aging, however, these fail to account intra-individual variance. To address limitation, we conducted longitudinal, pilot analysis that investigated segregation index ($SI$), simply defined ratio within-network connectivity relative between-network connectivity, across adult lifespan. Specifically, subset Calgary Normative Study data (67 individuals scanned twice over interval 3.1 ± 0.3 years, mean standard deviation) was analyzed. A linear mixed effects model used examine $Age,Age^{2}$, Sex, well Age $\times$ Sex interactions SI. We observed significant decline $SI$ with $\operatorname{Age}^{2}(t_{128}=-2.79,\ p\leq 0.001)$. Males demonstrated compared females $(t_{126}=-2.53,p=0.01$). By identifying $SI$, our study advances age-and sex-associated architecture, laying groundwork future work. In conclusion, confirms significance aging using longitudinal analysis. Using metric strengthened investigation combining within- into more robust reflects complex dynamic changes.

Language: Английский

Relationships between balance performance and connectivity of motor cortex with primary somatosensory cortex and cerebellum in middle aged and older adults DOI Open Access
Ashwini Sansare, Thamires Naela Cardoso Magalhães, Jessica A. Bernard

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: March 31, 2024

Connectivity of somatosensory cortex (S1) and cerebellum with the motor (M1) is critical for balance control. While both S1-M1 cerebellar-M1 connections are affected aging, implications altered connectivity control not known. We investigated relationship between standing in middle-aged older adults. Our secondary objective was to investigate how cognition balance. results show that greater related postural sway during standing. This may be indicative an increase functional recruitment additional brain networks maintain upright despite differences network connectivity. Also, moderated balance, such those lower had a stronger performance. It individuals poor need increased regions (compensation cognitive declines) turn, higher wiring costs, which would associated

Language: Английский

Citations

1
Idiosyncrasy and generalizability of contraceptive- and hormone-related functional connectomes across the menstrual cycle DOI Creative Commons
Katherine L. Bottenhorn, Taylor Salo, Emily G. Jacobs

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 26, 2024

Abstract Neuroendocrinology has received little attention in human neuroscience research, resulting a dearth of knowledge surrounding potent and dynamic modulators cognition behavior, as well brain structure function. This work addresses one such phenomenon by studying functional connectomics related to ovarian hormone fluctuations throughout the adult menstrual cycle. To do so, we used magnetic resonance imaging (fMRI) assessments from two dense, longitudinal datasets assess variations connectivity with respect endogenous exogenous endocrine factors First, replicated prior findings that common, group-level individual specific have similar relative contributions network organization. Second, found widespread hormonal contraceptive (HC) use, addition sparser estradiol- progesterone-related connectivity, differential generalizability these subnetworks suggests progestin-specific impacts on HC users. These results provide novel insight into within-individual changes organization across cycle extent which are shared between individuals, illuminating understudied phenomena reproductive health important information for all neuroimaging studies include participants who menstruate. Author Summary Endocrine modulation function is poorly understood. Human research long relied group- or coarse, stage-differences, overlooking considerable differences organization, cycle, concentrations. Here, take multi-dataset approach identify idiosyncratic contraceptive- hormone-related neuroendocrine dynamics then test this other individuals. In doing identified hormone-responsive somewhat generalizable though complicated potentially reflecting formulations. Thus, illuminates similarities

Language: Английский

Citations

0
Hormone-sleep interactions predict cerebellar connectivity and behavior in aging females DOI Creative Commons
Hannah K. Ballard, T. Bryan Jackson, Tracey H. Hicks

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2022, Volume and Issue: unknown

Published: Aug. 31, 2022

Abstract Sex hormones fluctuate over the course of female lifespan and are associated with brain health cognition. Thus, hormonal changes throughout adulthood, menopause in particular, may contribute to sex differences function behavior. Further, have been correlated sleep patterns, which also exhibit sex-specific impacts on As such, interplay between late-life behavioral outcomes females. Here, a sample healthy middle-aged older females (n = 79, ages 35-86), we evaluated effect hormone-sleep interactions cognitive motor performance as well cerebellar-frontal network connectivity. Salivary samples were used measure 17 β -estradiol, progesterone, testosterone levels while overnight actigraphy was quantify patterns. Cognitive behavior quantified using composite average standardized scores memory, processing speed, attentional tasks, indexed sequence learning, balance, dexterity tasks. We analyzed resting-state connectivity correlations for two specific networks: Crus I dorsolateral prefrontal cortex Lobule V primary network. In sum, results indicate that patterns interact predict aging Together, current findings further highlight potential consequences endocrine suggest link contribute, part, divergent sexes advanced age. Highlights Hormone-sleep influence impacted by relationships

Language: Английский

Citations

2
Cerebello-Hippocampal Interactions in the Human Brain: A New Pathway for Insights Into Aging DOI Open Access
Jessica A. Bernard

Published: Oct. 3, 2023

The cerebellum is recognized as being important for optimal behavioral performance across task domains, including motor function, cognition, and affect. Decades of work have highlighted cerebello-thalamo-cortical circuits, from both structural functional perspectives. However, these circuits interest been primarily (though not exclusively) focused on targets in the cerebral cortex. In addition to cortical connections, circuit linking hippocampus particular interest. Recently, there has an increased this circuit, thanks large part novel findings animal literature demonstrating that neuronal firing impacts hippocampus. Work human brain provided evidence interactions between hippocampus, though context spatial navigation. Given role regions cognition aging, emerging indicating impacted age-related neurodegenerative disease such Alzheimer’s, I propose further attention warranted. Here, provide overview cerebello-hippocampal models imaging outline possible utility investigations improve our understanding aging cognitive decline.

Language: Английский

Citations

0
Default Mode Network Segregation Decreases in Healthy Brain Aging DOI
Abhijot S Sidhu,

Talal H. Shahid,

Kauê Tartarotti Nepomuceno Duarte

et al.

Published: Nov. 15, 2023

The default mode network (DMN) constitutes a cluster of interconnected brain regions engaged in internal cognitive processes, such as interoception, memory recall, and self-referential thinking. DMN is task-negative network, displaying increased activity during rest but reduced tasks. Resting-state functional magnetic resonance imaging (rs-MRI) examines this nature by tracking low-frequency fluctuations the blood oxygenation level-dependent signal an indirect marker for changes activity. Many cross-sectional studies have focused on understanding organization healthy aging, however, these fail to account intra-individual variance. To address limitation, we conducted longitudinal, pilot analysis that investigated segregation index ($SI$), simply defined ratio within-network connectivity relative between-network connectivity, across adult lifespan. Specifically, subset Calgary Normative Study data (67 individuals scanned twice over interval 3.1 ± 0.3 years, mean standard deviation) was analyzed. A linear mixed effects model used examine $Age,Age^{2}$, Sex, well Age $\times$ Sex interactions SI. We observed significant decline $SI$ with $\operatorname{Age}^{2}(t_{128}=-2.79,\ p\leq 0.001)$. Males demonstrated compared females $(t_{126}=-2.53,p=0.01$). By identifying $SI$, our study advances age-and sex-associated architecture, laying groundwork future work. In conclusion, confirms significance aging using longitudinal analysis. Using metric strengthened investigation combining within- into more robust reflects complex dynamic changes.

Language: Английский

Citations

0