49 results on '"Benjamin Zimmerman"'
Search Results
2. Neurovascular mechanisms of cognitive aging: Sex-related differences in the average progression of arteriosclerosis, white matter atrophy, and cognitive decline
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Daniel C. Bowie, Kathy A. Low, Samantha L. Rubenstein, Samia S. Islam, Benjamin Zimmerman, Paul B. Camacho, Bradley P. Sutton, Gabriele Gratton, and Monica Fabiani
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Cognitive aging ,Cerebrovascular health ,Cerebral arterial pulse based on diffused optical tomography (pulse-DOT) ,Arteriosclerosis ,White matter lesions ,Sex differences ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Arterial stiffness (arteriosclerosis) has been linked to heightened risks for cognitive decline, and ultimately for Alzheimer's disease and other forms of dementia. Importantly, neurovascular outcomes generally vary according to one's biological sex. Here, capitalizing on a large sample of participants with neuroimaging and behavioral data (N = 203, age range = 18–87 years), we aimed to provide support for a hierarchical model of neurocognitive aging, which links age-related declines in cerebrovascular health to the rate of cognitive decline via a series of intervening variables, such as white matter integrity. By applying a novel piecewise regression approach to our cross-sectional sample to support Granger-like temporal inferences, we show that, on average, a precipitous decline in cerebral arterial elasticity (measured with diffuse optical imaging of the cerebral arterial pulse; pulse-DOT) precedes an acceleration in the development of white matter lesions by nearly a decade, with women protected from these deleterious effects until approximately age 50, the average onset of menopause. By employing multiple-mediator path analyses while controlling for sex, we show that age may impair cognition via the sequential indirect effects of arteriosclerosis and white matter atrophy on fluid, but not crystallized, abilities. Importantly, we replicate these results using pulse pressure, an independent index of arterial health, thereby providing converging evidence for the central role of arteriosclerosis as an accelerating factor in normal and pathological aging and identifying robust sex-related differences in the progression of cerebral arteriosclerosis and white matter degradation.
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- 2024
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3. Apolipoprotein E levels in the amygdala and prefrontal cortex predict relative regional brain volumes in irradiated Rhesus macaques
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Payel Kundu, Benjamin Zimmerman, Ruby Perez, Christopher T. Whitlow, J. Mark Cline, John D. Olson, Rachel N. Andrews, and Jacob Raber
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Medicine ,Science - Abstract
Abstract In the brain, apolipoprotein E (apoE) plays an important role in lipid transport and response to environmental and age-related challenges, including neuronal repair following injury. While much has been learned from radiation studies in rodents, a gap in our knowledge is how radiation might affect the brain in primates. This is important for assessing risk to the brain following radiotherapy as part of cancer treatment or environmental radiation exposure as part of a nuclear accident, bioterrorism, or a nuclear attack. In this study, we investigated the effects of ionizing radiation on brain volumes and apoE levels in the prefrontal cortex, amygdala, and hippocampus of Rhesus macaques that were part of the Nonhuman Primate Radiation Survivor Cohort at the Wake Forest University. This unique cohort is composed of Rhesus macaques that had previously received single total body doses of 6.5–8.05 Gy of ionizing radiation. Regional apoE levels predicted regional volume in the amygdala and the prefrontal cortex. In addition, apoE levels in the amygdala, but not the hippocampus, strongly predicted relative hippocampal volume. Finally, radiation dose negatively affected relative hippocampal volume when apoE levels in the amygdala were controlled for, suggesting a protective compensatory role of regional apoE levels following radiation exposure. In a supplementary analysis, there also was a robust positive relationship between the neuroprotective protein α-klotho and apoE levels in the amygdala, further supporting the potentially protective role of apoE. Increased understanding of the effects of IR in the primate brain and the role of apoE in the irradiated brain could inform future therapies to mitigate the adverse effects of IR on the CNS.
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- 2021
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4. Amifostine (WR-2721) Mitigates Cognitive Injury Induced by Heavy Ion Radiation in Male Mice and Alters Behavior and Brain Connectivity
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Sydney Weber Boutros, Benjamin Zimmerman, Sydney C. Nagy, Joanne S. Lee, Ruby Perez, and Jacob Raber
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amifostine ,heavy ion radiation ,cognition ,cFos ,sex differences ,Physiology ,QP1-981 - Abstract
The deep space environment contains many risks to astronauts during space missions, such as galactic cosmic rays (GCRs) comprised of naturally occurring heavy ions. Heavy ion radiation is increasingly being used in cancer therapy, including novel regimens involving carbon therapy. Previous investigations involving simulated space radiation have indicated a host of detrimental cognitive and behavioral effects. Therefore, there is an increasing need to counteract these deleterious effects of heavy ion radiation. Here, we assessed the ability of amifostine to mitigate cognitive injury induced by simulated GCRs in C57Bl/6J male and female mice. Six-month-old mice received an intraperitoneal injection of saline, 107 mg/kg, or 214 mg/kg of amifostine 1 h prior to exposure to a simplified five-ion radiation (protons, 28Si, 4He, 16O, and 56Fe) at 500 mGy or sham radiation. Mice were behaviorally tested 2–3 months later. Male mice that received saline and radiation exposure failed to show novel object recognition, which was reversed by both doses of amifostine. Conversely, female mice that received saline and radiation exposure displayed intact object recognition, but those that received amifostine prior to radiation did not. Amifostine and radiation also had distinct effects on males and females in the open field, with amifostine affecting distance moved over time in both sexes, and radiation affecting time spent in the center in females only. Whole-brain analysis of cFos immunoreactivity in male mice indicated that amifostine and radiation altered regional connectivity in areas involved in novel object recognition. These data support that amifostine has potential as a countermeasure against cognitive injury following proton and heavy ion irradiation in males.
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- 2021
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5. Longitudinal Effects of Immediate and Delayed Estradiol on Cognitive Performance in a Spatial Maze and Hippocampal Volume in Menopausal Macaques Under an Obesogenic Diet
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Benjamin Zimmerman, Payel Kundu, Zheng Liu, Henryk F. Urbanski, Christopher D. Kroenke, Steven G. Kohama, Cynthia L. Bethea, and Jacob Raber
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menopause ,hormone replacement therapy ,obesogenic diet ,neurodegeneration ,aging ,Neurology. Diseases of the nervous system ,RC346-429 - Abstract
The consumption of a diet high in fat and refined sugars has several health risks, including the development of cognitive decline and neurodegeneration. For women, menopause carries additional health risks that may interact with a high-fat diet in negative ways. Some symptoms of menopause, including cognitive impairments, can be modulated by hormone replacement therapy (HRT), but the hormonal formulation and the timing of the treatment relative to the onset of menopause are critical factors determining its efficacy. Little is known about how obesogenic, high-fat, high-sugar diets interact with HRT in menopause to affect cognition and neurodegeneration. Given the high prevalence of the consumption of an obesogenic Western-style diet, understanding how the effects of HRT are modulated by an obesogenic diet is critical for developing optimized therapeutic strategies for peri- and post-menopausal women. In this study, we investigated by magnetic resonance imaging (MRI) the effects of either immediate or delayed estradiol hormone therapy on cognition and neuroanatomy following ovo-hysterectomy (OvH) of aged, female rhesus macaques on an obesogenic diet. The macaques were followed for 2.5 years after ovo-hysterectomy, with four time points at which anatomical MRIs were acquired. Analysis of hippocampal volumes revealed an interaction between time point and treatment; hippocampal volumes in the delayed estrogen group, but not the immediate estrogen group, increased over time compared to those in untreated controls. Performance on a hippocampal-dependent spatial maze task showed improved performance in estrogen treated animals compared to OvH macaques given placebo. These results indicate that HRT may contribute to beneficial cognitive outcomes after menopause under an obesogenic diet.
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- 2020
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6. Functional Brain Changes During Mindfulness-Based Cognitive Therapy Associated With Tinnitus Severity
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Benjamin Zimmerman, Megan Finnegan, Subhadeep Paul, Sara Schmidt, Yihsin Tai, Kelly Roth, Yuguo Chen, and Fatima T. Husain
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tinnitus ,mindfulness-based cognitive therapy ,resting state MRI ,functional MRI ,graph connectivity analysis ,Neurosciences. Biological psychiatry. Neuropsychiatry ,RC321-571 - Abstract
Mindfulness-based therapies have been introduced as a treatment option to reduce the psychological severity of tinnitus, a currently incurable chronic condition. This pilot study of twelve subjects with chronic tinnitus investigates the relationship between measures of both task-based and resting state functional magnetic resonance imaging (fMRI) and measures of tinnitus severity, assessed with the Tinnitus Functional Index (TFI). MRI was measured at three time points: before, after, and at follow-up of an 8-week long mindfulness-based cognitive therapy intervention. During the task-based fMRI with affective sounds, no significant changes were observed between sessions, nor was the activation to emotionally salient compared to neutral stimuli significantly predictive of TFI. Significant results were found using resting state fMRI. There were significant decreases in functional connectivity among the default mode network, cingulo-opercular network, and amygdala across the intervention, but no differences were seen in connectivity with seeds in the dorsal attention network (DAN) or fronto-parietal network and the rest of the brain. Further, only resting state connectivity between the brain and the amygdala, DAN, and fronto-parietal network significantly predicted TFI. These results point to a mostly differentiated landscape of functional brain measures related to tinnitus severity on one hand and mindfulness-based therapy on the other. However, overlapping results of decreased amygdala connectivity with parietal areas and the negative correlation between amygdala-parietal connectivity and TFI is suggestive of a brain imaging marker of successful treatment.
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- 2019
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7. The Effect of High Fat Diet on Cerebrovascular Health and Pathology: A Species Comparative Review
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Benjamin Zimmerman, Payel Kundu, William D. Rooney, and Jacob Raber
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high-fat diet ,species differences ,cardiovascular health ,metabolism ,cerebrovasculature ,cognition ,Organic chemistry ,QD241-441 - Abstract
In both humans and animal models, consumption of a high-saturated-fat diet has been linked to vascular dysfunction and cognitive impairments. Laboratory animals provide excellent models for more invasive high-fat-diet-related research. However, the physiological differences between humans and common animal models in terms of how they react metabolically to high-fat diets need to be considered. Here, we review the factors that may affect the translatability of mechanistic research in animal models, paying special attention to the effects of a high-fat diet on vascular outcomes. We draw attention to the dissociation between metabolic syndrome and dyslipidemia in rodents, unlike the state in humans, where the two commonly occur. We also discuss the differential vulnerability between species to the metabolic and vascular effects of macronutrients in the diet. Findings from animal studies are better interpreted as modeling specific aspects of dysfunction. We conclude that the differences between species provide an opportunity to explore why some species are protected from the detrimental aspects of high-fat-diet-induced dysfunction, and to translate these findings into benefits for human health.
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- 2021
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8. The Optical Effective Attenuation Coefficient as an Informative Measure of Brain Health in Aging
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Antonio M. Chiarelli, Kathy A. Low, Edward L. Maclin, Mark A. Fletcher, Tania S. Kong, Benjamin Zimmerman, Chin Hong Tan, Bradley P. Sutton, Monica Fabiani, and Gabriele Gratton
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diffuse optical imaging (DOI) ,effective attenuation coefficient (EAC) ,aging ,cortical thinning ,FreeSurfer ,Applied optics. Photonics ,TA1501-1820 - Abstract
Aging is accompanied by widespread changes in brain tissue. Here, we hypothesized that head tissue opacity to near-infrared light provides information about the health status of the brain’s cortical mantle. In diffusive media such as the head, opacity is quantified through the Effective Attenuation Coefficient (EAC), which is proportional to the geometric mean of the absorption and reduced scattering coefficients. EAC is estimated by the slope of the relationship between source−detector distance and the logarithm of the amount of light reaching the detector (optical density). We obtained EAC maps across the head in 47 adults (age range 18−75 years), using a high-density dual-wavelength optical system. We correlated regional and global EAC measures with demographic, neuropsychological, structural and functional brain data. Results indicated that EAC values averaged across wavelengths were strongly associated with age-related changes in cortical thickness, as well as functional and neuropsychological measures. This is likely because the EAC largely depends on the thickness of the sub-arachnoid cerebrospinal fluid layer, which increases with cortical atrophy. In addition, differences in EAC values between wavelengths were correlated with tissue oxygenation and cardiorespiratory fitness, indicating that information about cortical health can be derived non-invasively by quantifying the EAC.
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- 2019
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9. Mapping cerebral pulse pressure and arterial compliance over the adult lifespan with optical imaging.
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Chin Hong Tan, Kathy A Low, Tania Kong, Mark A Fletcher, Benjamin Zimmerman, Edward L Maclin, Antonio M Chiarelli, Gabriele Gratton, and Monica Fabiani
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Medicine ,Science - Abstract
Cerebrovascular health is important for maintaining a high level of cognitive performance, not only in old age, but also throughout the lifespan. Recently, it was first demonstrated that diffuse optical imaging measures of pulse amplitude and arterial compliance can provide estimates of cerebral arterial health throughout the cortex, and were associated with age, estimated cardiorespiratory fitness (eCRF), neuroanatomy and cognitive function in older adults (aged 55-87). The current study replicates and extends the original findings using a broader age range (a new adult sample aged 18-75), longer recording periods (360 s), and a more extensive optical montage (1536 channels). These methodological improvements represent a 5-fold increase in recording time and a 4-fold increase in coverage compared to the initial study. Results show that reliability for both pulse amplitude and compliance measures across recording blocks was very high (r(45) = .99 and .75, respectively). Pulse amplitude and pulse pressure were shown to correlate with age across the broader age range. We also found correlations between arterial health and both cortical and subcortical gray matter volumes. Additionally, we replicated the correlations between arterial compliance and age, eCRF, global brain atrophy, and cognitive flexibility. New regional analyses revealed that higher performance on the operation span (OSPAN) working memory task was associated with greater localized arterial compliance in frontoparietal cortex, but not with global arterial compliance. Further, greater arterial compliance in frontoparietal regions was associated with younger age and higher eCRF. These associations were not present in the visual cortex. The current study not only replicates the initial one in a sample including a much wider age range, but also provides new evidence showing that frontoparietal regions may be especially vulnerable to vascular degeneration during brain aging, with potential functional consequences in cognition.
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- 2017
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10. Synthetic Cancer - Augmenting Worms with LLMs.
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Benjamin Zimmerman and David Zollikofer
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- 2024
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11. Robust and Scalable Entity Alignment in Big Data.
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James Flamino, Christopher Abriola, Benjamin Zimmerman, Zhongheng Li, and Joel Douglas
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- 2020
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12. Alexa, Are You Listening?: Privacy Perceptions, Concerns and Privacy-seeking Behaviors with Smart Speakers.
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Josephine Lau, Benjamin Zimmerman, and Florian Schaub
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- 2018
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13. Serum Levels of α-Klotho Are Correlated with Cerebrospinal Fluid Levels and Predict Measures of Cognitive Function
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Payel Kundu, Benjamin Zimmerman, Joseph F. Quinn, Jeffrey Kaye, Nora Mattek, Shawn K. Westaway, and Jacob Raber
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Aged, 80 and over ,General Neuroscience ,Apolipoprotein E4 ,General Medicine ,Mental Status and Dementia Tests ,urologic and male genital diseases ,female genital diseases and pregnancy complications ,Psychiatry and Mental health ,Clinical Psychology ,Cognition ,Alzheimer Disease ,mental disorders ,Humans ,Cognitive Dysfunction ,Geriatrics and Gerontology ,Klotho Proteins ,Biomarkers ,Aged - Abstract
Background: α-klotho might play a role in neurodegenerative diseases. Objective: To determine levels of α-klotho and apoE in serum and cerebrospinal fluid (CSF) samples and their relationship with the Mini-Mental State Examination (MMSE) and Clinical Dementia Rating (CDR). Methods: All subjects were between age 39 to 83+ (n = 94). CDR and MMSE were administered to all participants. CSF was collected in the early afternoon by lumbar puncture. Results: Serum and CSF levels of α-klotho are positively correlated and both predict scores on the MMSE and CDR, regardless of sex or apoE4 status. Conclusion: Our results demonstrate that α-klotho may be an important biomarker of cognitive health and neurodegeneration, and that relatively non-invasive sampling of α-klotho from serum is likely highly reflective of CSF levels.
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- 2022
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14. Age, sex, and apolipoprotein E isoform alter contextual fear learning, neuronal activation, and baseline DNA damage in the hippocampus
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Sydney Weber Boutros, Benjamin Zimmerman, Sydney C. Nagy, Vivek K. Unni, and Jacob Raber
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Cellular and Molecular Neuroscience ,Psychiatry and Mental health ,Molecular Biology - Abstract
Age, female sex, and apolipoprotein E4 (E4) are risk factors to develop Alzheimer’s disease (AD). There are three major human apoE isoforms: E2, E3, and E4. Compared to E3, E4 increases while E2 decreases AD risk. However, E2 is associated with increased risk and severity of post-traumatic stress disorder (PTSD). In cognitively healthy adults, E4 carriers have greater brain activation during learning and memory tasks in the absence of behavioral differences. Human apoE targeted replacement (TR) mice display differences in fear extinction that parallel human data: E2 mice show impaired extinction, mirroring heightened PTSD symptoms in E2 combat veterans. Recently, an adaptive role of DNA double strand breaks (DSBs) in immediate early gene expression (IEG) has been described. Age and disease synergistically increase DNA damage and decrease DNA repair. As the mechanisms underlying the relative risks of apoE, sex, and their interactions in aging are unclear, we used young (3 months) and middle-aged (12 months) male and female TR mice to investigate the influence of these factors on DSBs and IEGs at baseline and following contextual fear conditioning. We assessed brain-wide changes in neural activation following fear conditioning using whole-brain cFos imaging in young female TR mice. E4 mice froze more during fear conditioning and had lower cFos immunoreactivity across regions important for somatosensation and contextual encoding compared to E2 mice. E4 mice also showed altered co-activation compared to E3 mice, corresponding to human MRI and cognitive data, and indicating that there are differences in brain activity and connectivity at young ages independent of fear learning. There were increased DSB markers in middle-aged animals and alterations to cFos levels dependent on sex and isoform, as well. The increase in hippocampal DSB markers in middle-aged animals and female E4 mice may play a role in the risk for developing AD.
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- 2023
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15. Collaborative navigation systems for collision avoidance.
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Hassan A. Karimi, Benjamin Zimmerman, D. Nawn, and Peter Sutovsky
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- 2010
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16. SoNavNet: a framework for social navigation networks.
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Hassan A. Karimi, Benjamin Zimmerman, Alper Ozcelik, and Duangduen Roongpiboonsopit
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- 2009
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17. Grid-Based Geoprocessing for Integrated Global Navigation Satellite System Simulation.
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Hassan A. Karimi, Benjamin Zimmerman, Duangduen Roongpiboonsopit, and Abdelmounaam Rezgui
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- 2012
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18. Optical measures of cerebral arterial stiffness are associated with white matter signal abnormalities and cognitive performance in normal aging
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Chin Hong Tan, Tania S. Kong, Riccardo Navarra, Edward L. Maclin, Kathy A. Low, Antonio Maria Chiarelli, Benjamin Zimmerman, Monica Fabiani, Agnieszka Z. Burzynska, Gabriele Gratton, Mark A. Fletcher, Bradley P. Sutton, and School of Social Sciences
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0301 basic medicine ,Aging ,medicine.medical_specialty ,Fluid Abilities ,Article ,Healthy Aging ,White matter ,03 medical and health sciences ,Cognition ,Vascular Stiffness ,0302 clinical medicine ,Psychology [Social sciences] ,medicine.artery ,Internal medicine ,Humans ,Medicine ,Effects of sleep deprivation on cognitive performance ,Cognitive decline ,Relaxation (psychology) ,business.industry ,General Neuroscience ,Cerebral Arteries ,medicine.disease ,White Matter ,Hyperintensity ,030104 developmental biology ,medicine.anatomical_structure ,Middle cerebral artery ,Cardiology ,Arterial stiffness ,Neurology (clinical) ,Geriatrics and Gerontology ,business ,030217 neurology & neurosurgery ,Developmental Biology - Abstract
Decline in fluid abilities in normal aging is associated with increased white matter lesions, measured on T1-weighted images as white matter signal abnormalities (WMSAs). WMSAs are particularly evident in hypertensive older adults, suggesting vascular involvement. However, because hypertension is assessed systemically, the specific role of cerebral arterial stiffening in WMSAs has yet to be demonstrated. In 93 cognitively normal adults (aged 18-87 years), we used a novel method to measure cerebral arterial elasticity (pulse relaxation function [PReFx]) with diffuse optical tomography (pulse-DOT) and investigated its association with WMSAs, age, and cognition. PReFx was associated with WMSAs, with older adults with low PReFx showing the greatest WMSA burden. PReFx in brain regions perfused by the middle cerebral artery showed the largest associations with WMSAs and partially mediated the relationship between age and WMSAs. Finally, WMSAs partially mediated the relationship between PReFx and fluid but not crystallized abilities scores. Taken together, these findings suggest that loss of cerebral arterial elasticity is associated with cerebral white matter lesions and age-related cognitive decline. Accepted version
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- 2019
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19. Slow Cortical Waves through Cyclicity Analysis
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Somayeh Shahsavarani, Fatima T. Husain, Baryshnikov Y, Benjamin Zimmerman, and Ivan Thomas Abraham
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Physics ,Human Connectome Project ,Series (mathematics) ,Aperiodic graph ,Trajectory ,Base frequency ,Invariant (mathematics) ,Neuroscience ,Brain function - Abstract
Fine-grained understanding of dynamics in cortical networks is crucial in unpacking brain function. Here, we introduce a novel analytical method to characterize the dynamic interaction between distant brain regions, and apply it to data from the Human Connectome Project.Resting-state fMRI results in time series recordings of the activity of different brain regions, which are aperiodic and lacking a base frequency. Cyclicity Analysis, a novel technique robust with respect to time-reparametrizations, is effective in recovering temporal ordering of such time series along a circular trajectory without assuming any time-scale. Our analysis detected slow cortical waves of activity propagating across the brain with consistent lead-lag relationships between specific brain regions. We also observed short bursts of task-modulated strong temporal ordering that dominate overall lead-lag relationships between pairs of regions in the brain. Our results suggest the possible role played by slow waves of information transmission between brain regions that underlie emergent cognitive function.
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- 2021
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20. Apolipoprotein E levels in the amygdala and prefrontal cortex predict relative regional brain volumes in irradiated Rhesus macaques
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Jacob Raber, J. Mark Cline, Rachel N. Andrews, Payel Kundu, Benjamin Zimmerman, John Olson, Christopher T. Whitlow, and Ruby Perez
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Apolipoprotein E ,Male ,medicine.medical_treatment ,Science ,Hippocampus ,Prefrontal Cortex ,Neuroprotection ,Amygdala ,Article ,Ionizing radiation ,Apolipoproteins E ,biology.animal ,medicine ,Animals ,Primate ,Prefrontal cortex ,Klotho Proteins ,Neurons ,Multidisciplinary ,biology ,business.industry ,Brain ,Macaca mulatta ,Radiation therapy ,medicine.anatomical_structure ,Medicine ,Female ,business ,Neuroscience ,Biomarkers - Abstract
In the brain, apolipoprotein E (apoE) plays an important role in lipid transport and response to environmental and age-related challenges, including neuronal repair following injury. While much has been learned from radiation studies in rodents, a gap in our knowledge is how radiation might affect the brain in primates. This is important for assessing risk to the brain following radiotherapy as part of cancer treatment or environmental radiation exposure as part of a nuclear accident, bioterrorism, or a nuclear attack. In this study, we investigated the effects of ionizing radiation on brain volumes and apoE levels in the prefrontal cortex, amygdala, and hippocampus of Rhesus macaques that were part of the Nonhuman Primate Radiation Survivor Cohort at the Wake Forest University. This unique cohort is composed of Rhesus macaques that had previously received single total body doses of 6.5–8.05 Gy of ionizing radiation. Regional apoE levels predicted regional volume in the amygdala and the prefrontal cortex. In addition, apoE levels in the amygdala, but not the hippocampus, strongly predicted relative hippocampal volume. Finally, radiation dose negatively affected relative hippocampal volume when apoE levels in the amygdala were controlled for, suggesting a protective compensatory role of regional apoE levels following radiation exposure. In a supplementary analysis, there also was a robust positive relationship between the neuroprotective protein α-klotho and apoE levels in the amygdala, further supporting the potentially protective role of apoE. Increased understanding of the effects of IR in the primate brain and the role of apoE in the irradiated brain could inform future therapies to mitigate the adverse effects of IR on the CNS.
- Published
- 2021
21. Age‐related changes in cerebrovascular health and their effects on neural function and cognition: A comprehensive review
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Bart Rypma, Monica Fabiani, Gabriele Gratton, and Benjamin Zimmerman
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Aging ,Cognitive Neuroscience ,neurovascular coupling ,Psychological intervention ,Experimental and Cognitive Psychology ,Cognitive neuroscience ,Affect (psychology) ,050105 experimental psychology ,Introductory Review ,cerebrovascular reactivity ,03 medical and health sciences ,0302 clinical medicine ,Cognition ,Developmental Neuroscience ,Age related ,medicine ,Dementia ,Humans ,0501 psychology and cognitive sciences ,Biological Psychiatry ,cerebrovascular health ,Endocrine and Autonomic Systems ,cognitive aging ,General Neuroscience ,05 social sciences ,Neurosciences ,Brain ,Cardiorespiratory fitness ,medicine.disease ,Special Issue Title: Aging and Cerebrovascular Health: Structural, Functional, Cognitive, and Methodological Implications ,Neuropsychology and Physiological Psychology ,Neurology ,Cerebrovascular Circulation ,Neural function ,sense organs ,Psychology ,Neuroscience ,030217 neurology & neurosurgery ,dementia - Abstract
The process of aging includes changes in cellular biology that affect local interactions between cells and their environments and eventually propagate to systemic levels. In the brain, where neurons critically depend on an efficient and dynamic supply of oxygen and glucose, age‐related changes in the complex interaction between the brain parenchyma and the cerebrovasculature have effects on health and functioning that negatively impact cognition and play a role in pathology. Thus, cerebrovascular health is considered one of the main mechanisms by which a healthy lifestyle, such as habitual cardiorespiratory exercise and a healthful diet, could lead to improved cognitive outcomes with aging. This review aims at detailing how the physiology of the cerebral vascular system changes with age and how these changes lead to differential trajectories of cognitive maintenance or decline. This provides a framework for generating specific mechanistic hypotheses about the efficacy of proposed interventions and lifestyle covariates that contribute to enhanced cognitive well‐being. Finally, we discuss the methodological implications of age‐related changes in the cerebral vasculature for human cognitive neuroscience research and propose directions for future experiments aimed at investigating age‐related changes in the relationship between physiology and cognitive mechanisms., Impact Statement In this comprehensive review, we discuss, in detail, the physiology of how the cerebrovasculature can change with age and how these changes lead to differences in cognitive outcomes. The review provides a framework for generating mechanistic hypotheses about the efficacy of proposed interventions and lifestyle covariates that contribute to enhanced cognitive well‐being in aging and discusses methodological issues in human cognitive aging research related to cerebrovascular physiology.
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- 2021
22. Decreased resting perfusion in precuneus and posterior cingulate cortex predicts tinnitus severity
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Somayeh Shahsavarani, Benjamin Zimmerman, Rafay A. Khan, Sara A. Schmidt, Fatima T. Husain, and Yihsin Tai
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medicine.medical_specialty ,Arterial spin labeling ,Precuneus ,Neurosciences. Biological psychiatry. Neuropsychiatry ,Audiology ,Tinnitus ,Magnetic resonance imaging ,Cortex (anatomy) ,otorhinolaryngologic diseases ,Medicine ,Cerebral perfusion pressure ,medicine.diagnostic_test ,business.industry ,General Engineering ,Hearing loss ,Perfusion ,medicine.anatomical_structure ,Cerebral blood flow ,Posterior cingulate ,Default mode network ,medicine.symptom ,business ,Functional magnetic resonance imaging ,RC321-571 - Abstract
Functional magnetic resonance imaging has been increasingly used to understand the mechanisms involved in subjective tinnitus; however, researchers have struggled to reach a consensus about a primary mechanistic model to explain tinnitus. While many studies have used functional connectivity of the BOLD signal to understand how patterns of activity change with tinnitus severity, there is much less research on whether there are differences in more fundamental physiology, including cerebral blood flow, which may help inform the BOLD measures. Here, arterial spin labeling was used to measure perfusion in four regions-of-interest, guided by current models of tinnitus, in a sample of 60 tinnitus patients and 31 control subjects. We found global reductions in cerebral perfusion in tinnitus compared with controls. Additionally, we observed a significant negative correlation between tinnitus severity and perfusion. These results demonstrate that examining perfusion from the whole brain may present a complementary tool for studying tinnitus. More research will help better understand the physiology underlying these differences in perfusion.
- Published
- 2021
23. High-resolution magnetic resonance imaging-based atlases for the young and adolescent domesticated pig (Sus scrofa)
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Sangyun Joung, Bradley P. Sutton, Ryan N. Dilger, Joanne E. Fil, and Benjamin Zimmerman
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0301 basic medicine ,Male ,Swine ,Sus scrofa ,High resolution ,Neuroimaging ,Biology ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Image Processing, Computer-Assisted ,Image acquisition ,Animals ,Domestication ,medicine.diagnostic_test ,General Neuroscience ,Brain atlas ,Brain ,Magnetic resonance imaging ,Human brain ,Magnetic Resonance Imaging ,030104 developmental biology ,Cerebral blood volume ,medicine.anatomical_structure ,Female ,Cartography ,030217 neurology & neurosurgery ,Software - Abstract
Background Neurodevelopmental studies utilize the pig as a translational animal model due to anatomical and morphological similarities between the pig and human brain. However, neuroimaging resources are not as well developed for the pig as they are for humans and other animal models. We established a magnetic resonance imaging-based brain atlas at two different ages for biomedical studies utilizing the pig as a preclinical model. New Method Twenty artificially-reared domesticated male pigs (Sus scrofa) and thirteen sow-reared adolescent domesticated male pigs (Sus scrofa) underwent a series of scans measuring brain macrostructure, microstructure, and arterial cerebral blood volume. Results An atlas for the 4-week-old and 12-week-old pig were created along with twenty-six regions of interest. Normative data for brain measures were obtained and detailed descriptions of the data processing pipelines were provided. Comparison with Existing Method Atlases at the two different ages were created for the pig utilizing newer imaging technology and software. This facilitates the performance of longitudinal studies and enables more precise volume measurements in pigs of various ages by appropriately representing the neuroanatomical features of younger and older pigs and accommodating the proportion differences of the brain over time. Conclusion Two high-resolution MRI brain atlases specific to the domesticated young and adolescent pig were created using defined image acquisition and data processing methods to facilitate the generation of high-quality normative data for neurodevelopmental research.
- Published
- 2020
24. Large-area MRI-compatible epidermal electronic interfaces for prosthetic control and cognitive monitoring
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Levi J. Hargrove, Jue Zhang, Aadeel Akhtar, Paul V. Braun, Zhaoqian Xie, Jesse Cornman, Matthew Moore, Limei Tian, Jinghua Li, John A. Rogers, Benjamin Zimmerman, Ryan J. Larsen, Yuhao Liu, Gabriele Gratton, Yonggang Huang, Xiaogang Guo, Jian Wu, Michael Fatina, Monica Fabiani, Jung Woo Lee, Ki Jun Yu, Brian Metzger, Jonathan A. Fan, Florin Dolcos, Yinji Ma, Yihui Zhang, Kyle E. Mathewson, Timothy Bretl, and Subing Qu
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Adult ,Male ,0301 basic medicine ,Computer science ,Biomedical Engineering ,Medicine (miscellaneous) ,Wearable computer ,Bioengineering ,Electroencephalography ,law.invention ,Electrocardiography ,Wearable Electronic Devices ,03 medical and health sciences ,Cognition ,0302 clinical medicine ,law ,Eddy current ,medicine ,Humans ,Transhumeral prosthesis ,Electrodes ,integumentary system ,medicine.diagnostic_test ,Electromyography ,business.industry ,Mri compatible ,Magnetic resonance imaging ,Robotics ,Prostheses and Implants ,Magnetic Resonance Imaging ,Computer Science Applications ,030104 developmental biology ,Artificial intelligence ,Epidermis ,business ,Square centimetres ,030217 neurology & neurosurgery ,Biotechnology ,Biomedical engineering - Abstract
Skin-interfaced medical devices are critically important for diagnosing disease, monitoring physiological health and establishing control interfaces with prosthetics, computer systems and wearable robotic devices. Skin-like epidermal electronic technologies can support these use cases in soft and ultrathin materials that conformally interface with the skin in a manner that is mechanically and thermally imperceptible. Nevertheless, schemes so far have limited the overall sizes of these devices to less than a few square centimetres. Here, we present materials, device structures, handling and mounting methods, and manufacturing approaches that enable epidermal electronic interfaces that are orders of magnitude larger than previously realized. As a proof-of-concept, we demonstrate devices for electrophysiological recordings that enable coverage of the full scalp and the full circumference of the forearm. Filamentary conductive architectures in open-network designs minimize radio frequency-induced eddy currents, forming the basis for structural and functional compatibility with magnetic resonance imaging. We demonstrate the use of the large-area interfaces for the multifunctional control of a transhumeral prosthesis by patients who have undergone targeted muscle-reinnervation surgery, in long-term electroencephalography, and in simultaneous electroencephalography and structural and functional magnetic resonance imaging.
- Published
- 2019
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- View/download PDF
25. Changes in gray and white matter in subgroups within the tinnitus population
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Sara A. Schmidt, Jake R. Carpenter-Thompson, Richard O. Bido Medina, Fatima T. Husain, and Benjamin Zimmerman
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Adult ,Male ,0301 basic medicine ,medicine.medical_specialty ,Population ,Anxiety ,Audiology ,computer.software_genre ,White matter ,Tinnitus ,03 medical and health sciences ,0302 clinical medicine ,Region of interest ,Voxel ,Fractional anisotropy ,Image Processing, Computer-Assisted ,otorhinolaryngologic diseases ,Humans ,Medicine ,Gray Matter ,education ,Molecular Biology ,Aged ,Analysis of Variance ,education.field_of_study ,Depression ,business.industry ,General Neuroscience ,Middle Aged ,White Matter ,Diffusion Tensor Imaging ,030104 developmental biology ,medicine.anatomical_structure ,Anisotropy ,Regression Analysis ,Female ,Neurology (clinical) ,medicine.symptom ,business ,Gray (horse) ,computer ,030217 neurology & neurosurgery ,Developmental Biology ,Diffusion MRI - Abstract
In this study, we investigated gray and white matter changes in subgroups within the larger tinnitus population related to differences in severity or duration of tinnitus symptoms. Tinnitus is the illusory perception of sound in the absence of an external source, most often experienced as a chronic condition. The psychological reaction to the sound constitutes the severity, or degree of discomfort experienced, and the duration refers to the time since onset of chronic tinnitus. We used voxel- and surface-based morphometry to investigate gray matter changes and diffusion tensor imaging (using fractional anisotropy, or FA, metrics) to assess changes in orientation of white matter tracts, using both whole brain and region of interest analyses. Whole brain analyses revealed decreased cortical thickness in the left parahippocampal gyrus in those with more severe tinnitus compared to a group with a milder reaction, and reduced gray matter volume in left anterior cingulate in those with mild tinnitus compared to a normal hearing control group without tinnitus. In the analysis based on FA, no significant differences were revealed between the subgroups or with respect to control groups in either whole brain or region of interest analyses. Our results suggest that these subgroups within the tinnitus population likely exhibit different anatomical alterations related to the disorder, which may explain the variable findings in the literature, particularly in terms of gray matter.
- Published
- 2018
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26. Individual differences in regional cortical volumes across the life span are associated with regional optical measures of arterial elasticity
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Chin Hong Tan, Benjamin Zimmerman, Tania S. Kong, Antonio Maria Chiarelli, Edward L. Maclin, Kathy A. Low, Mark A. Fletcher, Monica Fabiani, Alexander Gorsuch, and Gabriele Gratton
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Adult ,Male ,Aging ,medicine.medical_specialty ,Adolescent ,Cognitive Neuroscience ,Cerebral arteries ,Cortical volume ,Article ,050105 experimental psychology ,Correlation ,Young Adult ,03 medical and health sciences ,Brain anatomy ,Vascular Stiffness ,0302 clinical medicine ,Atrophy ,Internal medicine ,Image Processing, Computer-Assisted ,medicine ,Humans ,Tomography, Optical ,0501 psychology and cognitive sciences ,Elasticity (economics) ,Aged ,Life span ,business.industry ,05 social sciences ,Brain ,Arterial elasticity ,Cerebral Arteries ,Middle Aged ,medicine.disease ,Elasticity ,Neurology ,Cardiology ,Female ,business ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Aging is often accompanied by changes in brain anatomy and cerebrovascular health. However, the specific relationship between declines in regional cortical volumes and loss of cerebral arterial elasticity is less clear, as only global or very localized estimates of cerebrovascular health have been available. Here we employed a novel tomographic optical method (pulse-DOT) to derive local estimates of cerebral arterial elasticity and compared regional volumetric estimates (obtained with FreeSurfer) with optical arterial elasticity estimates from the same regions in 47 healthy adults (aged 18–75). Between-subject analyses revealed a global correlation between cortical volume and cortical arterial elasticity, which was a significant mediator of the association between age and cortical volume. Crucially, a novel within-subject analysis highlighted the spatial association between regional variability in cortical volumes and arterial elasticity in the same regions. This association strengthened with age. Gains in the predictability of cortical volumes from arterial elasticity data were obtained by sharpening the resolution up to individual cortical regions. These results indicate that some of the variance of sub-clinical age-related brain atrophy is associated with differences in the status of cerebral arteries, and can help to explain the unique patterns of brain atrophy found within each individual.
- Published
- 2017
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27. Assessing mindfulness-based cognitive therapy intervention for tinnitus using behavioural measures and structural MRI: a pilot study
- Author
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Yihsin Tai, Robyn L. Gobin, Faaiza Khan, Christopher Menard, Megan K. Finnegan, Benjamin Zimmerman, Fatima T. Husain, and Emily Kay
- Subjects
Adult ,Male ,Linguistics and Language ,medicine.medical_specialty ,Mindfulness ,medicine.medical_treatment ,Pilot Projects ,Grey matter ,Audiology ,Language and Linguistics ,03 medical and health sciences ,Speech and Hearing ,Tinnitus ,0302 clinical medicine ,Hearing ,medicine ,Humans ,Gray Matter ,030223 otorhinolaryngology ,Mindfulness-based cognitive therapy ,Aged ,business.industry ,Voxel-based morphometry ,Middle Aged ,Magnetic Resonance Imaging ,Distress ,medicine.anatomical_structure ,Superior frontal gyrus ,Cognitive therapy ,Female ,medicine.symptom ,business ,030217 neurology & neurosurgery - Abstract
Objective: We used a minimally-modified version of Mindfulness-Based Cognitive Therapy (MBCT) to treat symptoms of distress associated with tinnitus.Design: Audiological screening (establishing a baseline) was conducted prior to treatment and at three time-points: pre-intervention, post-intervention and follow-up, 8 weeks after completion of training. MRI tests were also conducted at these three time-points.Study sample: Twenty-one participants were enrolled in the study, of whom 15 completed training and audiological testing and eight completed the MRI portion of the study.Results: Scores on tinnitus-related questionnaires showed a significant decline either from pre- to post-intervention or from pre-intervention to follow-up, despite no significant change during baseline. Voxel-based morphometric analysis of the structural MRI scans revealed clusters in bilateral superior frontal gyrus that exhibited significant increases in grey matter volume over the period of intervention and follow-up. Further, grey matter changes in occipital and cingulate regions correlated with declines in tinnitus handicap.Conclusions: This pilot study supports MBCT as an adequate approach for treating distressing tinnitus and suggests that neuroanatomical changes may reflect reductions in tinnitus-related severity. Although our small sample size precludes drawing strong conclusions, there is potential for assessing neuroanatomical changes due to mindfulness-based interventions in tinnitus.
- Published
- 2019
28. The optical effective attenuation coefficient as an informative measure of brain health in aging
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Chin Hong Tan, Monica Fabiani, Antonio Maria Chiarelli, Bradley P. Sutton, Gabriele Gratton, Mark A. Fletcher, Tania S. Kong, Edward L. Maclin, Benjamin Zimmerman, Kathy A. Low, and School of Social Sciences
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lcsh:Applied optics. Photonics ,Effective Attenuation Coefficient (EAC) ,Opacity ,cortical thinning ,FreeSurfer ,Brain tissue ,Optical density ,01 natural sciences ,Article ,010309 optics ,03 medical and health sciences ,Functional brain ,0302 clinical medicine ,Nuclear magnetic resonance ,Diffuse Optical Imaging (DOI) ,Psychology [Social sciences] ,0103 physical sciences ,Radiology, Nuclear Medicine and imaging ,Instrumentation ,Cortical atrophy ,Chemistry ,aging ,lcsh:TA1501-1820 ,Atomic and Molecular Physics, and Optics ,Tissue oxygenation ,Attenuation coefficient ,diffuse optical imaging (DOI) ,sense organs ,effective attenuation coefficient (EAC) ,Geometric mean ,030217 neurology & neurosurgery - Abstract
Aging is accompanied by widespread changes in brain tissue. Here, we hypothesized that head tissue opacity to near-infrared light provides information about the health status of the brain&rsquo, s cortical mantle. In diffusive media such as the head, opacity is quantified through the Effective Attenuation Coefficient (EAC), which is proportional to the geometric mean of the absorption and reduced scattering coefficients. EAC is estimated by the slope of the relationship between source&ndash, detector distance and the logarithm of the amount of light reaching the detector (optical density). We obtained EAC maps across the head in 47 adults (age range 18&ndash, 75 years), using a high-density dual-wavelength optical system. We correlated regional and global EAC measures with demographic, neuropsychological, structural and functional brain data. Results indicated that EAC values averaged across wavelengths were strongly associated with age-related changes in cortical thickness, as well as functional and neuropsychological measures. This is likely because the EAC largely depends on the thickness of the sub-arachnoid cerebrospinal fluid layer, which increases with cortical atrophy. In addition, differences in EAC values between wavelengths were correlated with tissue oxygenation and cardiorespiratory fitness, indicating that information about cortical health can be derived non-invasively by quantifying the EAC.
- Published
- 2019
29. Taking the pulse of aging: Mapping pulse pressure and elasticity in cerebral arteries with optical methods
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Mark A. Fletcher, Kathy A. Low, Gabriele Gratton, Chin Hong Tan, Nils Schneider-Garces, Antonio Maria Chiarelli, Monica Fabiani, Bradley P. Sutton, Edward L. Maclin, and Benjamin Zimmerman
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medicine.medical_specialty ,Endocrine and Autonomic Systems ,Cognitive Neuroscience ,General Neuroscience ,Cerebral arteries ,Neuropsychology ,Experimental and Cognitive Psychology ,Cardiorespiratory fitness ,Disease ,Pulse pressure ,White matter ,Neuropsychology and Physiological Psychology ,medicine.anatomical_structure ,Developmental Neuroscience ,Neurology ,Cerebral blood flow ,Internal medicine ,medicine ,Cardiology ,Cognitive decline ,Psychology ,Biological Psychiatry - Abstract
Cerebrovascular support is crucial for healthy cognitive and brain aging. Arterial stiffening is a cause of reduced brain blood flow, a predictor of cognitive decline, and a risk factor for cerebrovascular accidents and Alzheimer's disease. Arterial health is influenced by lifestyle factors, such as cardiorespiratory fitness (CRF). We investigated new noninvasive optical measures of cerebrovascular health, which provide estimates of arterial pulse parameters (pulse pressure, transit time, and compliance/elasticity) within specific cerebral arteries and cortical regions, and low-resolution maps of large superficial cerebral arteries. We studied naturally occurring variability in these parameters in adults (aged 55-87), and found that these indices of cerebrovascular health are negatively correlated with age and positively with CRF and gray and white matter volumes. Further, regional pulse transit time predicts specific neuropsychological performance.
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- 2014
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30. Publisher Correction: Large-area MRI-compatible epidermal electronic interfaces for prosthetic control and cognitive monitoring
- Author
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Brian Metzger, Ki Jun Yu, Yihui Zhang, Jue Zhang, Aadeel Akhtar, Levi J. Hargrove, Florin Dolcos, Jung Woo Lee, Zhaoqian Xie, Jian Wu, Jinghua Li, Jonathan A. Fan, Yinji Ma, Limei Tian, Michael Fatina, Kyle E. Mathewson, Subing Qu, Paul V. Braun, Xiaogang Guo, Timothy Bretl, Ryan J. Larsen, John A. Rogers, Matthew Moore, Yonggang Huang, Monica Fabiani, Gabriele Gratton, Benjamin Zimmerman, Yuhao Liu, and Jesse Cornman
- Subjects
0301 basic medicine ,business.industry ,Bar (music) ,Computer science ,Biomedical Engineering ,Mri compatible ,Medicine (miscellaneous) ,Bioengineering ,Cognition ,Computer Science Applications ,03 medical and health sciences ,030104 developmental biology ,0302 clinical medicine ,business ,030217 neurology & neurosurgery ,Computer hardware ,Biotechnology ,Biomedical engineering - Abstract
In Fig. 4c of this Article, the scale bar units were incorrectly stated as ‘μV’; the correct units are ‘mV’. The figure has now been amended accordingly.
- Published
- 2019
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31. Mapping cerebral pulse pressure and arterial compliance over the adult lifespan with optical imaging
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Tania Kong, Mark A. Fletcher, Chin Hong Tan, Kathy A. Low, Antonio Maria Chiarelli, Edward L. Maclin, Monica Fabiani, Gabriele Gratton, and Benjamin Zimmerman
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Central Nervous System ,Male ,Aging ,Intracranial Pressure ,Blood Pressure ,030204 cardiovascular system & hematology ,Audiology ,Brain mapping ,Nervous System ,Vascular Medicine ,Diagnostic Radiology ,0302 clinical medicine ,Cognition ,Learning and Memory ,Elderly ,Medicine and Health Sciences ,Aged, 80 and over ,Cognitive Impairment ,Multidisciplinary ,Cognitive Neurology ,Radiology and Imaging ,Cognitive flexibility ,Middle Aged ,Magnetic Resonance Imaging ,Pulse pressure ,medicine.anatomical_structure ,Memory, Short-Term ,Neurology ,Anesthesia ,Cerebrovascular Circulation ,Medicine ,Female ,Anatomy ,Research Article ,Adult ,medicine.medical_specialty ,Adolescent ,Imaging Techniques ,Cognitive Neuroscience ,Science ,Research and Analysis Methods ,03 medical and health sciences ,Vascular Stiffness ,Diagnostic Medicine ,Memory ,medicine ,Humans ,Cognitive Dysfunction ,Effects of sleep deprivation on cognitive performance ,Working Memory ,Aged ,Working memory ,business.industry ,Biology and Life Sciences ,Compliance (physiology) ,Blood pressure ,Visual cortex ,Age Groups ,People and Places ,Cognitive Science ,Population Groupings ,business ,030217 neurology & neurosurgery ,Neuroscience - Abstract
Cerebrovascular health is important for maintaining a high level of cognitive performance, not only in old age, but also throughout the lifespan. Recently, it was first demonstrated that diffuse optical imaging measures of pulse amplitude and arterial compliance can provide estimates of cerebral arterial health throughout the cortex, and were associated with age, estimated cardiorespiratory fitness (eCRF), neuroanatomy and cognitive function in older adults (aged 55-87). The current study replicates and extends the original findings using a broader age range (a new adult sample aged 18-75), longer recording periods (360 s), and a more extensive optical montage (1536 channels). These methodological improvements represent a 5-fold increase in recording time and a 4-fold increase in coverage compared to the initial study. Results show that reliability for both pulse amplitude and compliance measures across recording blocks was very high (r(45) = .99 and .75, respectively). Pulse amplitude and pulse pressure were shown to correlate with age across the broader age range. We also found correlations between arterial health and both cortical and subcortical gray matter volumes. Additionally, we replicated the correlations between arterial compliance and age, eCRF, global brain atrophy, and cognitive flexibility. New regional analyses revealed that higher performance on the operation span (OSPAN) working memory task was associated with greater localized arterial compliance in frontoparietal cortex, but not with global arterial compliance. Further, greater arterial compliance in frontoparietal regions was associated with younger age and higher eCRF. These associations were not present in the visual cortex. The current study not only replicates the initial one in a sample including a much wider age range, but also provides new evidence showing that frontoparietal regions may be especially vulnerable to vascular degeneration during brain aging, with potential functional consequences in cognition.
- Published
- 2017
32. Battery-free, stretchable optoelectronic systems for wireless optical characterization of the skin
- Author
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Kyoungyeon Cho, Yonggang Huang, Hitoshi Araki, Kyung In Jang, Zhaoqian Xie, Jeonghyun Kim, Xue Feng, Hongying Luo, Monica Fabiani, Ungyu Paik, Benjamin Zimmerman, Yuhao Liu, Seung Yun Heo, John A. Rogers, Antonio Maria Chiarelli, Jung Woo Lee, Anthony Banks, Joonhee Kim, Lingqing Yan, Giovanni A. Salvatore, Xing Sheng, Sheng Xu, and Gabriele Gratton
- Subjects
Battery (electricity) ,skin ,Computer science ,Battery-free ,NFC ,bio-integrated ,healthcare ,near-field communication ,optical ,optoelectronics ,stretchable ,wireless ,Blood Pressure ,Epidermis ,Heart Rate ,Oximetry ,Radiation Dosimeters ,Regional Blood Flow ,Biosensing Techniques ,Electronics ,Skin ,Skin Physiological Phenomena ,Wireless Technology ,Interface (computing) ,education ,Digital data ,Wearable computer ,Photodetector ,Bioengineering ,02 engineering and technology ,010402 general chemistry ,01 natural sciences ,Settore ING-INF/01 - Elettronica ,Near field communication ,health services administration ,Wireless ,Research Articles ,Multidisciplinary ,integumentary system ,business.industry ,SciAdv r-articles ,equipment and supplies ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,Characterization (materials science) ,Optoelectronics ,0210 nano-technology ,business ,Research Article - Abstract
Recent advances in materials, mechanics, and electronic device design are rapidly establishing the foundationsfor health monitoring technologies that have“skin-like”properties, with options in chronic (weeks) integrationwith the epidermis. The resulting capabilities in physiological sensing greatly exceed those possible withconventional hard electronic systems, such as those found in wrist-mounted wearables, because of the intimateskin interface. However, most examples of such emergingclasses of devices require batteries and/or hard-wiredconnections to enable operation. The work reported here introduces active optoelectronic systems that functionwithout batteries and in an entirely wireless mode, with examples in thin, stretchable platforms designed formultiwavelength optical characterization of the skin. Magnetic inductive coupling and near-field communication(NFC) schemes deliver power to multicolored light-emitting diodes and extract digital data from integratedphotodetectors in ways that are compatible with standard NFC-enabled platforms, such as smartphones andtablet computers. Examples in the monitoring of heart rate and temporal dynamics of arterial blood flow, inquantifying tissue oxygenation and ultraviolet dosimetry, and in performing four-color spectroscopic evaluation ofthe skin demonstrate the versatility of these concepts. The results have potential relevance in both hospitalcare and at-home diagnostics., Science Advances, 2 (8), ISSN:2375-2548
- Published
- 2016
33. Comparing Aging and Fitness Effects on Brain Anatomy
- Author
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Benjamin Zimmerman, Rachel Boyd, Brian A. Gordon, Gabriele Gratton, Nils Schneider-Garces, Monica Fabiani, Bradley P. Sutton, Kathy A. Low, Mark A. Fletcher, and Chin Hong Tan
- Subjects
medicine.medical_specialty ,FreeSurfer ,Poison control ,050105 experimental psychology ,03 medical and health sciences ,Behavioral Neuroscience ,Brain anatomy ,0302 clinical medicine ,Atrophy ,Physical medicine and rehabilitation ,Medicine ,0501 psychology and cognitive sciences ,10. No inequality ,Beneficial effects ,Biological Psychiatry ,Original Research ,cardiorespiratory fitness ,exercise ,biology ,business.industry ,aging ,05 social sciences ,Neurogenesis ,Cardiorespiratory fitness ,medicine.disease ,Psychiatry and Mental health ,Neuropsychology and Physiological Psychology ,Neurology ,biology.protein ,Fitness effects ,business ,brain anatomy ,Neuroscience ,030217 neurology & neurosurgery ,Neurotrophin - Abstract
Recent studies suggest that cardiorespiratory fitness (CRF) mitigates the brain’s atrophy typically associated with aging, via a variety of beneficial mechanisms. One could argue that if CRF is generally counteracting the negative effects of aging, the same regions that display the greatest age-related volumetric loss should also show the largest beneficial effects of fitness. To test this hypothesis we examined structural MRI data from 54 healthy older adults (ages 55–87), to determine the overlap, across brain regions, of the profiles of age and fitness effects. Results showed that lower fitness and older age are associated with atrophy in several brain regions, replicating past studies. However, when the profiles of age and fitness effects were compared using a number of statistical approaches, the effects were not entirely overlapping. Interestingly, some of the regions that were most influenced by age were among those not influenced by fitness. Presumably, the age-related atrophy occurring in these regions is due to factors that are more impervious to the beneficial effects of fitness. Possible mechanisms supporting regional heterogeneity may include differential involvement in motor function, the presence of adult neurogenesis, and differential sensitivity to cerebrovascular, neurotrophic and metabolic factors.
- Published
- 2016
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34. Printed Carbon Nanotubes on Polymer Films for Active Origami
- Author
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Eric Kincaid, Qazi Aied Iqbal, Brett Yost, Emily D. Sutton, Sivan Markowitz, Candace K. Chan, Takayuki Nosaka, Pai Liu, Katelyn Keberle, Michael J. O'Connell, Terry Alford, Chengwei Wang, Rodrigo Mendez, Kwai S. Chan, and Benjamin Zimmerman
- Subjects
chemistry.chemical_classification ,Materials science ,Fabrication ,Carbon nanotube actuators ,Carbon nanotube ,Polymer ,engineering.material ,law.invention ,chemistry ,Coating ,law ,Printed electronics ,engineering ,General Materials Science ,Composite material ,Actuator ,Layer (electronics) - Abstract
We describe a facile fabrication of solid-state actuators by coating common polymer films with a layer of carbon nanotubes. The composite material actuators are multifunctional energy transducers and were powered by heat, light, or electricity. The maximum observed force produced by an actuator was 60 times its own weight. Actuators were also demonstrated to bend more than 90°. The actuators were repeatedly activated for nearly 50,000 cycles without significant loss of performance for a sub-hertz actuator and 1,000,000 cycles in the case of a 30 Hz actuator. The utility of these devices was demonstrated by creating a walking robot.
- Published
- 2012
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- View/download PDF
35. Knowledge Network for Authoring, Reviewing, Editing, Searching, and Using Scientific or Other Credible Information
- Author
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David Nawn, Douglas Kondziolka, Benjamin Zimmerman, and Kenneth Sochats
- Subjects
World Wide Web ,Multimedia ,Process (engineering) ,Computer science ,Report types ,Ask price ,Continuous feedback ,computer.software_genre ,Structuring ,World science ,computer - Abstract
Video The existing paradigm of the scientific literature—individual authoring and editing, parallel review, a format that allows only reading—has not changed in over a century. The barriers to authorship, use, and the creation of scientific works are significant. We developed a new literature format based on an interactive network to address the needs of all parties, from author to user. We began by structuring the writing of text and data for a discipline's needs. Five report types were created, with menus for specific terms and data to allow online, simultaneous, multiauthor writing and editing. A new measurable peer-review process was created. Users can ask questions of reports, and data from multiple reports can be combined. A topic search is associated with automated research tools. We built a prototype that was built and refined based on continuous feedback from surveys, expert panels, presentations, and other feedback mechanisms. In continuous development, the free network World Science (w...
- Published
- 2012
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36. Optical measures of changes in cerebral vascular tone during voluntary breath holding and a Sternberg memory task
- Author
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Chin Hong Tan, Benjamin Zimmerman, Gabriele Gratton, Nils Schneider-Garces, Monica Fabiani, Edward L. Maclin, Mark A. Fletcher, Kathy A. Low, and Antonio Maria Chiarelli
- Subjects
Male ,medicine.medical_specialty ,Vasodilation ,Brain mapping ,Cerebral autoregulation ,050105 experimental psychology ,Article ,Breath Holding ,03 medical and health sciences ,Cerebral circulation ,0302 clinical medicine ,Memory ,Internal medicine ,medicine ,Humans ,0501 psychology and cognitive sciences ,Aged ,Aged, 80 and over ,Brain Mapping ,Psychological Tests ,Pulse (signal processing) ,General Neuroscience ,05 social sciences ,Optical Imaging ,Brain ,Blood flow ,Middle Aged ,Magnetic Resonance Imaging ,Neuropsychology and Physiological Psychology ,Blood pressure ,Vasoconstriction ,Cerebrovascular Circulation ,Cardiology ,Female ,medicine.symptom ,Psychology ,030217 neurology & neurosurgery - Abstract
The human cerebral vasculature responds to changes in blood pressure and demands for oxygenation via cerebral autoregulation. Changes in cerebrovascular tone (vasoconstriction and vasodilation) also mediate the changes in blood flow measured by the BOLD fMRI signal. This cerebrovascular reactivity is known to vary with age. In two experiments, we demonstrate that cerebral pulse parameters measured using optical imaging can quantify changes in cerebral vascular tone, both globally and locally. In experiment 1, 51 older adults (age range = 55–87) performed a voluntary breath-holding task while cerebral pulse amplitude measures were taken. We found significant pulse amplitude variations across breath-holding periods, indicating vasodilation during, and vasoconstriction after breath holding. The breath-holding index (BHI), a measure of cerebrovascular reactivity (CVR) was derived and found to correlate with age. BHI was also correlated with performance in the Modified Mini-Mental Status Examination, even after controlling for age and education. In experiment 2, the same participants performed a Sternberg task, and changes in regional pulse amplitude between high (set-size 6) and low (set-size 2) task loads were compared. Only task-related areas in the fronto-parietal network (FPN) showed significant reduction in pulse amplitude, indicating vasodilation. Non-task-related areas such as the somatosensory and auditory cortices did not show such reductions. Taken together, these experiments suggest that optical pulse parameters can index changes in brain vascular tone both globally and locally, using both physiological and cognitive load manipulations.
- Published
- 2015
37. Responsiveness vs. basal activity of plasma ANG II as a determinant of arterial pressure salt sensitivity
- Author
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Stephen A. Katz, Sandra L. Soucheray, John P. Collister, Pilar Ariza-Nieto, John W. Osborn, and Benjamin Zimmerman
- Subjects
Male ,medicine.medical_specialty ,Sympathetic Nervous System ,Physiology ,Sodium ,Hemodynamics ,chemistry.chemical_element ,Blood Pressure ,Rats, Sprague-Dawley ,Renin-Angiotensin System ,Heart Rate ,Physiology (medical) ,Internal medicine ,Renin–angiotensin system ,medicine ,Animals ,Vasoconstrictor Agents ,Enalapril ,Sodium Chloride, Dietary ,Salt intake ,biology ,Chemistry ,Angiotensin II ,Rats ,Blood pressure ,Endocrinology ,Enzyme inhibitor ,cardiovascular system ,biology.protein ,Cardiology and Cardiovascular Medicine ,hormones, hormone substitutes, and hormone antagonists ,medicine.drug - Abstract
Infusion of angiotensin II (ANG II) causes salt-sensitive hypertension. It is unclear whether this is due to the body's inability to suppress ANG II during increased salt intake or, rather, an elevated basal level of plasma ANG II itself. To distinguish between these mechanisms, Sprague-Dawley rats were instrumented with arterial and venous catheters for measurement of arterial pressure and infusion of drugs, respectively. The sensitivity of arterial pressure to salt was measured in four groups with the following treatments: 1) saline control (Con, n = 12); 2) administration of the angiotensin-converting enzyme inhibitor enalapril to block endogenous ANG II (ANG-Lo, n = 10); 3) administration of enalapril and 5 ng · kg–1 · min–1 ANG II to clamp plasma ANG II at normal levels (ANG-Norm, n = 10); and 4) administration of enalapril and 20 ng · kg–1 · min–1 ANG II to clamp ANG II at high levels (ANG-Hi, n = 10). Rats ingested a 0.4% NaCl diet for 3 days and then a 4.0% NaCl diet for 11 days. Arterial pressure of rats fed the 0.4% NaCl diet was lower in ANG-Lo (84 ± 2 mmHg) compared with Con (101 ± 3 mmHg) and ANG-Norm (98 ± 4 mmHg) groups, whereas ANG-Hi rats were hypertensive (145 ± 4 mmHg). Salt sensitivity was expressed as the change in arterial pressure divided by the change in sodium intake on the last day of the 4.0% NaCl diet. Salt sensitivity (in mmHg/meq Na) was lowest in Con rats (0.0 ± 0.1) and progressed from ANG-Lo (0.8 ± 0.2) to ANG-Norm (1.5 ± 0.5) to ANG-Hi (3.5 ± 0.5) rats. We conclude that the major determinant of salt sensitivity of arterial pressure is the basal level of plasma ANG II rather than the responsiveness of the renin-angiotensin system.
- Published
- 2003
- Full Text
- View/download PDF
38. Contributors
- Author
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Claude Alain, Pedro B. Albuquerque, Søren K. Andersen, David E. Anderson, Stephen R. Arnott, Edward Awh, James A. Brissenden, Douglas Cheyne, Christos Constantinidis, Nelson Cowan, Rhodri Cusack, Martin Eimer, Stephen M. Emrich, Monica Fabiani, Alexandra M. Fernandes, Ulysse Fortier-Gauthier, Keisuke Fukuda, Susan Gillingham, Gabriele Gratton, Su Keun Jeong, Pierre Jolicoeur, Tobias Katus, Simon Lacey, Rebecca Lawson, Christine Lefebvre, Ada W.S. Leung, Annika C. Linke, René Marois, Julio Martinez-Trujillo, Diego Mendoza-Halliday, Sophie Nolden, Tatiana Pasternak, Amy Poremba, Bradley R. Postle, Xue-Lian Qi, Eunsam Shin, Santiago Torres, Edward K. Vogel, Jeffrey Wong, Geoffrey F. Woodman, Yaoda Xu, Xin Zhou, and Benjamin Zimmerman
- Published
- 2015
- Full Text
- View/download PDF
39. Working Memory and Aging
- Author
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Monica Fabiani, Benjamin Zimmerman, and Gabriele Gratton
- Subjects
Behavioral data ,Neuroimaging ,Working memory ,Short-term memory ,Sensory system ,sense organs ,Childhood memory ,Normal aging ,skin and connective tissue diseases ,Psychology ,Cognitive psychology - Abstract
In this chapter, we review research on the sensory and working memory changes that typically accompany normal aging, with the view that an examination of individual differences over the lifespan can illuminate some of the mechanisms underlying working memory processes. We also discuss the theoretical frameworks used to interpret these age-related changes and provide an integrated view encompassing both behavioral and brain imaging data. Behavioral data show age-related changes in both the maintenance and attention-control aspects of working memory, suggesting a balance change between the top-down and bottom-up processing streams. Brain imaging studies provide evidence for anatomical and functional changes in the brain networks associated with working memory and the top-down control of attention.
- Published
- 2015
- Full Text
- View/download PDF
40. Cardiorespiratory fitness mediates the effects of aging on cerebral blood flow
- Author
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Edward L. Maclin, Yanfen Li, Kathy A. Low, Bradley P. Sutton, Benjamin Zimmerman, Chin Hong Tan, Nils Schneider-Garces, Monica Fabiani, Cheng Ouyang, Gabriele Gratton, and Mark A. Fletcher
- Subjects
medicine.medical_specialty ,Cognitive Neuroscience ,cerebral blood flow ,perfusion ,lcsh:RC321-571 ,White matter ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,Aerobic exercise ,Original Research Article ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,030304 developmental biology ,0303 health sciences ,cardiorespiratory fitness ,business.industry ,aging ,Cardiorespiratory fitness ,Blood flow ,arterial spin labeling ,vascular health ,medicine.anatomical_structure ,Cerebral blood flow ,Brain size ,Arterial spin labeling ,Cardiology ,business ,Perfusion ,Neuroscience ,030217 neurology & neurosurgery - Abstract
The brain’s vasculature is likely to be subjected to the same age-related physiological and anatomical changes affecting the rest of the cardiovascular system. Since aerobic fitness is known to alleviate both cognitive and volumetric losses in the brain, it is important to investigate some of the possible mechanisms underlying these beneficial changes. Here we investigated the role that estimated cardiorespiratory fitness (eCRF) plays in determining the relationship between aging and cerebral blood flow (CBF) in a group of older adults (ages 55-85). Using arterial spin labeling to quantify CBF, we found that blood flow in the gray matter was positively correlated with eCRF and negatively correlated with age. Subsequent analyses revealed that eCRF fully mediated the effects of age on CBF in the gray matter, but not in the white matter. Additionally, regional measures of CBF were related to regional measures of brain volume. These findings provide evidence that age-related effects on cerebrovascular health and perfusion in older adults are largely influenced by their eCRF levels.
- Published
- 2014
41. Taking the pulse of aging: mapping pulse pressure and elasticity in cerebral arteries with optical methods
- Author
-
Monica, Fabiani, Kathy A, Low, Chin-Hong, Tan, Benjamin, Zimmerman, Mark A, Fletcher, Nils, Schneider-Garces, Edward L, Maclin, Antonio M, Chiarelli, Bradley P, Sutton, and Gabriele, Gratton
- Subjects
Aged, 80 and over ,Male ,Aging ,Cerebrovascular Disorders ,Optical Imaging ,Humans ,Blood Pressure ,Female ,Cerebral Arteries ,Middle Aged ,Elasticity ,Article ,Aged - Abstract
Cerebrovascular support is crucial for healthy cognitive and brain aging. Arterial stiffening is a cause of reduced brain blood flow, a predictor of cognitive decline, and a risk factor for cerebrovascular accidents and Alzheimer’s disease. Arterial health is influenced by lifestyle factors, such as cardiorespiratory fitness (CRF). We investigated new noninvasive optical measures of cerebrovascular health, which provide estimates of arterial pulse parameters (pulse pressure, transit time, and compliance/elasticity) within specific cerebral arteries and cortical regions, and low-resolution maps of large superficial cerebral arteries. We studied naturally occurring variability in these parameters in adults (aged 55–87), and found that these indices of cerebrovascular health are negatively correlated with age and positively with CRF and gray and white matter volumes. Further, regional pulse transit time predicts specific neuropsychological performance.
- Published
- 2014
42. White matter matters for grey(ing) areas: a functional and structural view of task switching dynamics in middle-to-old age
- Author
-
Pauline, Baniqued, primary, Kathy, Low, additional, Mark, Fletcher, additional, Nils, Schneider-Garces, additional, Chin Hong, Tan, additional, Benjamin, Zimmerman, additional, Gabriele, Gratton, additional, and Monica, Fabiani, additional
- Published
- 2015
- Full Text
- View/download PDF
43. A Functional and Structural Network View of Task-Switching Dynamics in Ageing
- Author
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Pauline, Baniqued, primary, Kathy, Low, additional, Mark, Fletcher, additional, Nils, Schneider-Garces, additional, Chin Hong, Tan, additional, Benjamin, Zimmerman, additional, Gabriele, Gratton, additional, and Monica, Fabiani, additional
- Published
- 2015
- Full Text
- View/download PDF
44. Tracking Brain Plasticity in Cochlear Implant Patients Using the Event-Related Optical Signal (EROS)
- Author
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Chun-Yu, Tse, primary, Michael, Novak, additional, Chin-Hong, Tan, additional, Jennifer, Black, additional, Brian, Gordon, additional, Ed, Maclin, additional, Benjamin, Zimmerman, additional, Gabriele, Gratton, additional, and Monica, Fabiani, additional
- Published
- 2015
- Full Text
- View/download PDF
45. Retinotopic visual mapping of brain oxygenation and neuronal activity using simultaneous fast and slow near-infrared optical brain imaging in humans
- Author
-
Tania Kong, Mark A. Fletcher, Gabriele Gratton, Nils Schneider-Garces, Monica Fabiani, Antonio Maria Chiarelli, Courtney R. Burton, Chin Hong Tan, Kathy A. Low, Edward L. Maclin, Benjamin Zimmerman, Kyle E. Mathewson, and Brad Sutton
- Subjects
Ophthalmology ,Neuroimaging ,Chemistry ,Near-infrared spectroscopy ,Premovement neuronal activity ,Oxygenation ,Neuroscience ,Sensory Systems - Published
- 2014
- Full Text
- View/download PDF
46. Rosemary Catherine Keenan, violin
- Author
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Keenan, Rosemary Catherine; Marconi, Amanda; Yoder, Benjamin; Zimmerman, Lori; Fang, Emily, Ball State University. School of Music, Keenan, Rosemary Catherine; Marconi, Amanda; Yoder, Benjamin; Zimmerman, Lori; Fang, Emily, and Ball State University. School of Music
- Abstract
With Amanda Marconi, piano, Benjamin Yoder, violin, Lori Zimmerman, viola, and Emily Fang, cello., Series LVIII, Number 162., This archival material has been provided for educational purposes. Ball State University Libraries recognizes that some historic items may include offensive content. Our statement regarding objectionable content is available at: https://dmr.bsu.edu/digital/about
- Published
- 2004
47. Centella Asiatica in Older Adults
- Author
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Benjamin Zimmerman, Post-Doctoral Research Investigator
- Published
- 2024
48. THE DIFFERENCES BETWEEN MEAN BLOOD FLOW AND VASCULAR REACTIVITY AND THEIR RELATIONSHIPS WITH AGE, FITNESS, AND COGNITION IN OLDER ADULTS
- Author
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Benjamin Zimmerman, Sutton, Bradley P., Low, Kathy A., Tan, Chin Hong, Fletcher, Mark A., Schneider-Garces, Nils, Maclin, Edward L., Gratton, Gabriele, and Fabiani, Monica
49. CEREBRAL BLOOD FLOW IN THE AGING BRAIN IS MEDIATED BY CARDIORESPIRATORY FITNESS AND IS ASSOCIATED WITH COGNITIVE PERFORMANCE
- Author
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Benjamin Zimmerman, Sutton, Bradley P., Low, Kathy A., Schneider-Garces, Nils, Fletcher, Mark A., Tan, Chin-Hong, Li, Yanfen, Cheng, Ouyang, Maclin, Edward L., Gratton, Gabriele, and Fabiani, Monica
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