Biology subjects

Mather, M.

Publications and source records attributed to Mather, M..

At least 19 recordsLinked to original sources

bioRxiv2026

In-vivo MRI of noradrenergic and dopaminergic nuclei predicts future cognition and Alzheimers disease progression

Noradrenergic and dopaminergic nuclei modulate cognition, and post-mortem data indicate they are affected early in the neurodegenerative cascade of Alzheimers disease. We derived in-vivo locus coeruleus (LC) and substantia nigra-ventral tegmental area (SN-VTA) MRI integrity measures from 739 ADNI participants, examined MRI-histology correspondence in individuals with both in-vivo imaging and post-mortem data, and tested whether these measures reflect early MRI-indexed degeneration predicting later cognitive decline. LC and SN-VTA contrast predicted cognitive and behavioral function 10 years later, despite only weak associations with current function. LC- and SN-VTA-associated brain-wide atrophy patterns aligned with PET-derived norepinephrine-transporter and dopamine-receptor maps, respectively. A one-standard-deviation decrease in baseline LC contrast was associated with 84% higher five-year odds of MCI-to-AD progression, and predictive effects of the catecholaminergic nuclei were mediated by their corresponding atrophy patterns. The SN-VTA pattern was associated with less amyloid PET-related memory decline. Together, these findings establish LC and SN-VTA MRI contrast as markers of early neurodegeneration that forecast cognitive decline years before clinical onset.

neuroscience↗

bioRxiv2026

Distinct spatial organization of human hippocampal perfusion and microvascular pulsatility across age

Arterial pulsation can modulate neuronal activity through mechanosensitive pathways in mice, but whether vascular pulsatility is similarly related to neural organization in humans remains unclear. Here, using 7T MRI in 35 young and older adults, we mapped cerebral perfusion and microvascular volumetric pulsatility index (mvPI) across the unfolded hippocampus and integrated these measures with histological, electrophysiological, and transcriptomic reference maps. Perfusion and mvPI exhibited distinct spatial organization and age-related differences. In young adults, perfusion preferentially corresponded to parvalbumin-interneuron density and beta/gamma distribution, whereas mvPI was associated with theta-band distribution. A number of associations detected in young adults were not detected in the older adults maps. Spectral simulations showed qualitative similarity to heartbeat-related phase resetting as one possible explanation for the mvPI-theta relationship, while spatial transcriptomics revealed perivascular enrichment of PIEZO2, a candidate mediator of vascular mechanotransduction. Together, these findings establish perfusion and tissue-level pulsatility as distinct dimensions of human hippocampal vascular organization and provide a framework for investigating their relationships with neural dynamics across aging.

neuroscience↗

bioRxiv2026

Distinct Neural Systems Supporting Afferent and Efferent Autonomic Activity

Numerous studies have reported brain correlates of autonomic activity. However, ambiguity exists regarding whether those correlates reflect receiving or sending out autonomic signals. Additionally, little is known about how emotion and aging interact with brain-autonomic coordination. Based on time-varying heart rate variability (HRV) and blood oxygenation level dependent (BOLD) data (N = 104 younger; N = 51 older adults), we found insular and cingulate activity was negatively correlated with HRV during emotion regulation. We further examined the afferent and efferent nature of HRV-BOLD correlations during rest (N = 102 younger; N = 51 older adults). Functionally afferent regions where decreases in HRV were associated with subsequently increased BOLD activity included the posterior insula, postcentral gyrus and frontal pole. Functionally efferent regions where increased activity was associated with subsequently increased HRV included the anterior insula and cingulate. Information appeared to flow in one direction as the afferent regions activity Granger-predicted the efferent regions activity. Together, our findings suggest a feedback loop where decreased HRV increases the afferent regions activity, which activates the efferent regions, leading to increased HRV. Aging seems to affect this system; the efferent and afferent regions scarcely overlapped for younger adults, but did overlap for older adults.

neuroscience↗

bioRxiv2025

Effects of different slow paced breathing regimes on cerebrospinal fluid (CSF) oscillations

Cerebrospinal fluid (CSF) transport is crucial for clearing waste from the brain and is largely driven by blood vessel oscillatory dynamics. During non-REM sleep, large oscillations occur in the infraslow range around 0.02-0.03 Hz, where noradrenergically driven vasomotion, blood volume and CSF flow are tightly coupled. Whether an infraslow oscillation induced by respiration can engage comparable dynamics during wakefulness is unknown. Utilizing a fast neuroimaging technique, we investigated the effects of four different slow paced respiratory conditions on CSF oscillations in 35 healthy adults (aged 18-30): paced breathing at 0.09-0.11 Hz and 0.05-0.07 Hz, and paced sighing at 0.05-0.07 Hz and 0.02-0.03 Hz. All four conditions increased respiratory volume, low-frequency respiratory power, CSF oscillatory power and BOLD global signal amplitude relative to rest, and CSF power did not differ among them. However, the infraslow slow sighing produced significantly higher CSF-BOLD coupling than all the other conditions, together with the largest global signal amplitude, an index associated with reduced arousal. This effect of infraslow sighing was not linked with respiratory power, as paced breathing at 0.05-0.07 Hz had the greatest respiratory power yet the weakest CSF-BOLD coupling, falling below rest. Cardiac spectral power was also lower during infraslow sighing than during any other breathing manipulation. Stimulating oscillatory dynamics via respiration during wakefulness therefore may recruit neurovascular-CSF coupling due to the same infraslow-specific dynamics that are believed to drive sleep-dependent waste clearance. Our study provides evidence that slow paced breathing increases CSF oscillations during wakefulness. Furthermore, we found that sighing at the frequency of the infraslow band linked to glymphatic clearance increases the coupling between blood and CSF dynamics.

neuroscience↗

bioRxiv2025

Distributed fMRI patterns coupled to low-frequency cardiorespiratory dynamics provide markers of aging

How aging affects brain-body connections can be investigated through changes in the coupling between functional magnetic resonance imaging (fMRI) signals and bodily autonomic processes across the adult lifespan. Recent studies using univariate approaches have identified age-related changes in the association between fMRI signals from multiple individual brain regions and low-frequency respiratory and cardiac activity. Here, we investigate if whole-brain spatial fMRI patterns associated with low-frequency physiological processes (heart rate and respiratory volume fluctuations) present generalizable changes with age. Data from human participants of both sexes are included in the analysis. We find that chronological age can be predicted statistically beyond chance from patterns of low-frequency fMRI-physiology coupling, even after accounting for individual differences in physiological signal characteristics and brain anatomy. Notably, brain areas implicated in central autonomic regulation, including nodes within salience and ventral attention networks (e.g., insula and middle cingulate cortex), are amongst the strongest contributors to age prediction. Further, we observe that after removing physiological effects from fMRI data, the residual blood oxygen level-dependent (BOLD) signal variability is still a reliable indicator of age. Together, these findings underscore the close integration between brain and body physiology, and highlight this interaction as a potential biomarker of the aging process. Significance StatementThe association between brain activity and respiratory or cardiac activity is often dismissed as "noise" in functional magnetic resonance imaging (fMRI) studies. However, emerging evidence suggests that coupling between fMRI and peripheral physiological signals can provide valuable insight into the brain-body connection. In this study, we show that whole brain patterns of coupling between fMRI signals and low-frequency respiratory and cardiac processes can reliably predict age across the adult lifespan. Brain regions involved in autonomic regulation, such as insula and cingulate cortex, were among the most informative predictors of age. These findings suggest that fMRI-physiology coupling may capture aging-related changes in brain vascular health and autonomic function and may have broader relevance for tracking disease-related disruptions in brain-body interaction.

neuroscience↗

bioRxiv2025

Detecting Mitochondrial Free Radicals with Quantum Sensors: From Organelles to a D. melanogaster Model of Neurodegeneration

This study identifies a distinct free radical signature in a D. melanogaster model of Parkinsons Disease, successfully differentiating Pink1-deficient flies from wild-type controls. This insight was achieved using a robust quantum sensing methodology for the selective detection of free radicals in biological systems. Our approach utilizes optically detected magnetic resonance (ODMR) and magnetic modulation (MM) protocols with nanodiamond nitrogen-vacancy (NV) centres. Selective identification is achieved using the spin probe TEMPOL, a cell-permeable superoxide dismutase 2 (SOD2) mimic that initially quenches the photoluminescence signal. Upon scavenging free radicals like hydroxyl and superoxide, TEMPOL is converted to a diamagnetic adduct, restoring the contrast and thus enabling quantitative detection. The approach was first validated in a chemical system with radical generation confirmed by electron paramagnetic resonance (EPR) spectroscopy. It was then demonstrated across biological scales, from isolated mitochondria and whole glioblastoma cells to the Drosophila model. In these studies, high-resolution respirometry revealed distinct free radical signatures, and findings were compared with NV T1 relaxometry. This work provides new biophysical insight into mitochondrial dysfunction, demonstrating a distinct free radical signature in a neurodegeneration model and connecting it to specific metabolic states.

cell biology↗

bioRxiv2025

Assessing molecular, cellular and transcriptomic bases of laminar perfusion and cytoarchitecture coupling in the human cortex

Understanding how cellular architecture organizes cortical function requires mesoscopic approaches that resolve structure-function coupling in vivo. Here we introduce cerebral blood flow (CBF) and cell-body staining intensity (CSI) similarity index (CCSI), a localized similarity index between the CBF estimates from ultra-high-field 7T arterial spin labeling images and CSI from the BigBrain histology images to serve as a quantitative marker of laminar perfusion-cytoarchitecture coupling. CCSI revealed a reproducible, region- specific alignment between laminar vascular and cellular profiles across the cortex. Going beyond CBF, CCSI selectively tracked mitochondrial respiratory capacity and colocalized with capillary endothelial and mature non-myelination oligodendrocyte populations forming neurovascular interfaces. Transcriptomic enrichment highlighted pathways related to vascular remodeling, oxidative metabolism, and lipid-myelin homeostasis, indicating that CCSI reflects integrated metabolic-structural specialization. At the systems level, CCSI strengthened structure-function gradient correspondence in transmodal cortices, such as the default mode network. Together, these findings establish CCSI as a physiologically grounded, non-invasive marker of perfusion-cytoarchitecture alignment, providing a cross-scale framework linking cortical microstructure, metabolism, and functional organization.

neuroscience↗

bioRxiv2025

Arousal increases locus coeruleus blood flow, salience-related brain responses, and modulates negative-valence attentional biases

The amygdala helps prioritize emotional over neutral information. However, it responds similarly to positive and negative stimuli, and so is unlikely to be the source of valence-specific effects within affective networks. We hypothesized that the locus coeruleus (LC) is a key contributor to negative biases in attention. Using ultra-high field 7T magnetic resonance imaging, we tested how arousal modulates processing of emotional faces during an oddball task in twenty-two young adults during two separate sessions. Arousal induced by isometric handgrip increased LC cerebral blood flow and amplified brain responses to target and angry faces, but not to happy faces. The amygdala exhibited valence-general responses that were not modulated by arousal. LC connectivity with the default mode network decreased during processing target and angry faces, and arousal further modulated responses in the salience network and visual cortex. Behaviorally, arousal enhanced recognition of angry faces only when allocating attentional resources and memory performance was linked to left LC brain activity. These findings highlight the LC as a key structure through which arousal shapes valence processing, biases attention, and informs mechanisms related to affective disorders.

neuroscience↗

bioRxiv2025

Electroencephalography, pupillometry, and behavioral evidence for locus coeruleus-noradrenaline system related tonic hyperactivity in older adults

Neuroimaging studies have shown that age-related dysregulation of the locus coeruleus-noradrenaline (LC-NA) system is associated with cognitive decline. However, due to limitations in directly measuring LC function in vivo, it remains unclear whether age-related alterations in humans reflect tonic LC-NA system hyper- or hypoactivity, constraining our understanding of underlying mechanisms and hampers the development of targeted preventative interventions. In this study, we tested the hypothesis that cognitively healthy older adults sustain tonic LC hyperactivity, by acquiring electrophysiological, pupillometric, and behavioral measures during a passive and active auditory oddball paradigm. We capitalized on the LC-NA systems role in arousal regulation and manipulated state arousal using the unpredictable threat of electric shock. We hypothesized that if older adults maintain elevated LC activity compared with young adults, task-evoked noradrenergic responses would be less responsive to arousal in older adults. Consistent with this hypothesis, arousal elicited weaker behavioral responses, pupil dilation responses, and P300 event-related potentials in older adults compared with young adults. Linear mixed models revealed an arousal by modality interaction, showing that arousal differentially modulated attentional control to salient but task-irrelevant distractors between both age groups. Collectively, these findings support the hypothesis that aging is associated with tonic LC-NA system hyperactivity in humans, with neuromodulatory consequences for mechanisms of attentional control. Furthermore, the multimodal approach underscores the potential of non-invasive physiological markers to assess LC-NA system function throughout aging and identify individuals at elevated risk for neurodegenerative progression prior to the emergence of clinical biomarkers. Highlights- Behavioral, pupil and EEG data indicate LC-NA tonic hyperactivity in older adults. - Arousal modulates attentional control differently in young vs. older adults. - Older adults show increased distractibility from reduced habituation. - Arousal differentially modulates alpha power and aperiodic activity across age groups. - Phasic noradrenergic responses are modulated by state, arousal, and attention.

neuroscience↗

bioRxiv2025

Locus coeruleus-related insula activation supports implicit learning

The noradrenergic locus coeruleus and its neuromodulatory cortical projections are critical for adaptive behavior, however how they contribute to human implicit learning in novel environments is not yet well understood, due to the challenges of assessing this system non-invasively. Here, we combined multimodal neuroimaging--including locus-coeruleus-sensitive structural MRI, concurrent pupillometry-EEG, pupillometry-fMRI, and PET-derived noradrenergic transporter maps--with repeated behavioral assessments to investigate noradrenergic contributions to implicit learning across younger and older adults (n = 77). Salient expectation-violating stimuli elicited pupil dilation, indicating enhanced neuromodulation, activated the action-mode network and deactivated the default-mode network. Pupil-linked BOLD responses suggested a functional coupling between the locus coeruleus and action-mode network, further supported by spatial overlap of activation patterns with PET-derived noradrenergic transporter maps. Locus coeruleus MRI-guided functional connectivity analyses demonstrated coupled locus coeruleus and anterior insula activity, suggesting a noradrenergic role in shifting cortical dynamics toward action-oriented processing. Behaviorally, participants implicitly learned the statistical task structure over time, shifting their response times based on stimulus probabilities. Critically, stronger locus coeruleus integrity, greater task-related anterior insula activation, and more pronounced pupil dilation were associated with enhanced implicit learning, highlighting the behavioral relevance of noradrenergic neuromodulation. Notably, noradrenergic responses and their link to learning were preserved across age groups, suggesting a robust noradrenergic role in supporting adaptive behavior throughout adulthood. Complementary electrophysiological analyses revealed pupil-linked increases in cortical excitability that were coupled with shifts from default-mode to action-mode network activation. Together, these findings provide novel insights into the neuromodulatory mechanisms underlying learning and cognitive flexibility, emphasizing the pivotal role of locus coeruleus-action-mode network interactions in behavioral adaptation.

neuroscience↗

bioRxiv2025

The Physiological Component of the BOLD Signal: Impact of Age and Heart Rate Variability Biofeedback Training

Aging is associated with declines in autonomic nervous system (ANS) function, including reduced heart rate variability (HRV), impaired neurovascular coupling, and diminished cerebrovascular responsiveness--factors that may contribute to cognitive decline and neurodegenerative diseases. Understanding how aging alters physiological signal integration in the brain is crucial for identifying potential interventions to promote brain health. This study examines age-related differences in how cardiac and respiratory fluctuations influence the blood oxygenation level-dependent (BOLD) signal, using two independent resting-state fMRI datasets with concurrent physiological recordings from younger and older adults. Our findings reveal significant age-related reductions in the percent variance of the BOLD signal explained by heart rate (HR), respiratory variation (RV), and end-tidal CO2, particularly in regions involved in autonomic regulation, including the orbitofrontal cortex, anterior cingulate cortex, insula, basal ganglia, and white matter. Cross-correlation analysis also revealed that younger adults exhibited stronger HR-BOLD coupling in white matter, as well as a more rapid BOLD response to RV and CO2 in gray matter. Additionally, we investigated the effects of heart rate variability biofeedback (HRV-BF) training, a non-invasive intervention designed to modulate heart rate oscillations. The intervention altered physiological-BOLD coupling in an age- and training-dependent manner: older adults who underwent HRV-BF to enhance HR oscillations exhibited a shift toward younger-like HR-BOLD coupling patterns, while younger adults who trained to suppress HR oscillations showed increased CO2-BOLD coupling. These findings suggest that HRV-BF may help mitigate age-related declines in autonomic or cerebrovascular function. Overall, this study underscores the role of physiological dynamics in brain aging and highlights the importance of considering autonomic function when interpreting BOLD signals. By demonstrating that HRV-BF can modulate physiological-BOLD interactions, our findings suggest a potential pathway for enhancing cerebrovascular function and preserving brain health across the lifespan.

neuroscience↗

bioRxiv2024

Eye movements reveal age differences in how arousal modulates saliency priority but not attention processing speed

The arousal-biased competition theory posits that inducing arousal increases attentional priority of salient stimuli while reducing priority of non-pertinent stimuli. However, unlike in young adults, older adults rarely exhibit shifts in priority under increased arousal, and prior studies have proposed different neural mechanisms to explain how arousal differentially modulates selective attention in older adults. Therefore, we investigated how the threat of unpredictable shock differentially modulates attentional control mechanisms in young and older adults by observing eye movements. Participants completed two oculomotor search tasks in which the salient distractor was typically captured by attention (singleton search) or proactively suppressed (feature search). We found that arousal did not modulate attentional priority for any stimulus among older adults nor affect the speed of attention processing in either age group. Furthermore, we observed that arousal modulated pupil sizes and found a correlation between evoked pupil responses and oculomotor function. Our findings suggest age differences in how the locus coeruleus-noradrenaline system interacts with neural networks of attention and oculomotor function. Highlights- Increased arousal modulates attention saliency priority but not processing speed - Older adults do not exhibit shifts in stimulus priority under elevated arousal - Proactive suppression of salient stimuli persists even during increased arousal - Threat of unpredictable shock increases pupil sizes and decreases evoked responses - Eye movements may be able to help assess locus coeruleus function

neuroscience↗

bioRxiv2022

The integrity of dopaminergic and noradrenergic brain regions is associated with different aspects of late-life memory performance

Researchers have identified changes in dopaminergic neuromodulation as playing a key role in adult memory decline. Facilitated by technical advancements, recent research has also implicated noradrenergic neuromodulation in shaping late-life memory performance. However, it is not yet clear whether these two neuromodulators have distinct roles in age-related cognitive changes. Combining longitudinal high-resolution magnetic resonance imaging of the dopaminergic substantia nigra-ventral tegmental area (SN-VTA) and the noradrenergic locus coeruleus (LC) in younger (n = 69) and older adults (n = 251), we found that dopaminergic and noradrenergic integrity are differentially associated with individual differences in memory performance. While LC integrity was related to better episodic memory across several memory tasks, SN-VTA integrity was linked to working memory. Moreover, consistent with their dense interconnection and a largely shared biosynthesis, dopaminergic and noradrenergic brain regions integrity were positively related, and correlated with medial temporal lobe volumes. Longitudinally, we found that older age was associated with more-negative change in SN- VTA and LC integrity (time point 1-time point 2; mean delay [~]1.9 years). Importantly, changes in LC integrity reliably predicted future episodic memory performance (at time point 3). These findings support the feasibility of in-vivo indices for catecholaminergic integrity with potential clinical utility, given the degeneration of both neuromodulatory systems in several age-associated diseases. Moreover, they highlight differential roles of dopaminergic and noradrenergic neuromodulatory nuclei in late-life cognitive decline.

neuroscience↗

bioRxiv2022

Multi-organ functions of yolk sac during human early development

The yolk sac (YS) represents an evolutionarily-conserved extraembryonic structure that ensures timely delivery of nutritional support and oxygen to the developing embryo. However, the YS remains ill-defined in humans. We therefore assemble a complete single cell 3D map of human YS from 3-8 post conception weeks by integrating multiomic protein and gene expression data. We reveal the YS as a site of primitive and definitive haematopoiesis including a YS-specific accelerated route to macrophage production, a source of nutritional/metabolic support and a regulator of oxygen-carrying capacity. We reconstruct the emergence of primitive haematopoietic stem and progenitor cells from YS hemogenic endothelium and their decline upon stromal support modulation as intraembryonic organs specialise to assume these functions. The YS therefore functions as three organs in one revealing a multifaceted relay of vital organismal functions as pregnancy proceeds. One Sentence SummaryHuman yolk sac is a key staging post in a relay of vital organismal functions during human pregnancy.

developmental biology↗

bioRxiv2022

Associations between locus coeruleus MRI contrast and physiological responses to acute stress in younger and older adults

Acute stress activates the brains locus coeruleus (LC)-noradrenaline system. Recent studies indicate that a magnetic resonance imaging (MRI)-based measure of LC structure is associated with better cognitive outcomes in later life. Yet despite the LCs documented role in promoting physiological arousal during acute stress, no studies have examined whether MRI-assessed LC structure is related to arousal responses to acute stress. In this study, 102 younger and 51 older adults completed an acute stress induction task while we assessed multiple measures of physiological arousal (heart rate, breathing rate, systolic and diastolic blood pressure, sympathetic tone, and heart rate variability, HRV). We used turbo spin echo MRI scans to quantify LC MRI contrast as a measure of LC structure. We applied univariate and multivariate approaches to assess how LC MRI contrast was associated with arousal at rest and during acute stress reactivity and recovery. In older participants, having higher caudal LC MRI contrast was associated with greater stress-related increases in systolic blood pressure and decreases in HRV, as well as lower HRV during recovery from acute stress. These results suggest that having higher caudal LC MRI contrast in older adulthood is associated with more pronounced physiological responses to acute stress. Further work is needed to confirm these patterns in larger samples of older adults.

neuroscience↗

bioRxiv2021

Age Differences in Diffusivity in the Locus Coeruleus and its Ascending Noradrenergic Tract

The noradrenergic locus coeruleus (LC) is a small brainstem nucleus that promotes arousal and attention. Recent studies have examined the microstructural properties of the LC using diffusion-weighted magnetic resonance imaging and found unexpected age-related differences in fractional anisotropy - a measure of white matter integrity. Here, we used three datasets (Berlin Aging Study-II, N = 301, the Leipzig Study for Mind-Body-Emotion Interactions, N = 220, and Stockholm Sleepy Brain, N = 49), to replicate published findings and expand them by investigating diffusivity in the LCs ascending noradrenergic bundle. In younger adults, LC fractional anisotropy was significantly lower, compared to older adults. However, in the LCs ascending noradrenergic bundle, we observed significantly higher fractional anisotropy in younger adults, relative to older adults. These findings indicate that diffusivity in the LC versus the ascending noradrenergic bundle are both susceptible to microstructural changes in aging that have opposing effects on fractional anisotropy. HighlightsO_LIFractional anisotropy in the locus coeruleus was lower in younger adults C_LIO_LIFractional anisotropy in the noradrenergic bundle was higher in younger adults C_LIO_LISleep deprivation may affect diffusivity in younger adults more than older adults C_LI

neuroscience↗

bioRxiv2021

Emotion Down- and Up-Regulation Act on Spatially Distinct Brain Areas:Interoceptive Regions to Calm Down and Other Affective Regions to Amp Up

Prior studies on emotion regulation identified a set of brain regions specialized for generating and controlling affect. Researchers generally agree that when up- and down-regulating emotion, control regions in the prefrontal cortex turn up or down activity in affect-generating areas. However, the assumption that turning up and down emotions produces opposite effects in the same affect-generating regions is untested. We call this assumption the affective dial hypothesis. Our study tested this hypothesis by examining the overlap between the sets of regions activated during up-regulation and those deactivated during down-regulation in a large number of participants (N=105). We found that up- and down-regulation both recruit regulatory regions such as the inferior frontal gyrus and dorsal anterior cingulate gyrus but act on distinct affect-generating regions. While up-regulation increases BOLD signal in regions associated with emotion such as the amygdala, anterior insula, striatum and anterior cingulate gyrus as well as in regions associated with sympathetic vascular activity such as periventricular white matter, down-regulation decreases signal in regions receiving interoceptive input such as the posterior insula and postcentral gyrus. These findings indicate that up- and down-regulation do not generally exert opposing effects on the same affect-generating regions. Instead, they target different brain circuits. Significance StatementMany contexts require modulating ones own emotions. Identifying the brain areas implementing these regulatory processes should advance understanding emotional disorders and designing potential interventions. The emotion regulation field has an implicit assumption we call the affective dial hypothesis: that both emotion up- and down-regulation modulate the same emotion-generating brain areas. Countering the hypothesis, our findings indicate that up- and down-modulating emotions target different brain areas. Thus, the mechanisms underlying emotion regulation differ more than previously appreciated for up- versus down-regulation. In addition to their theoretical importance, these findings are critical for researchers attempting to target activity in particular brain regions during an emotion regulation intervention.

neuroscience↗

bioRxiv2021

Behavioral and fMRI evidence that arousal enhances bottom-up attention and memory selectivity in young but not older adults

During a challenge or emotional experience, increases in arousal help us focus on the most salient or relevant details and ignore distracting stimuli. The noradrenergic system integrates signals about arousal states throughout the brain and helps coordinate this adaptive attentional selectivity. However, age-related changes in the noradrenergic system and attention networks in the brain may reduce the efficiency of arousal to modulate selective processing in older adults. In the current neuroimaging study, we examined age differences in how arousal affects bottom-up attention to category-selective stimuli differing in perceptual salience. We found a dissociation in how arousal modulates selective processing in the young and older brain. In young adults, emotionally arousing sounds enhanced selective incidental memory and brain activity in the extrastriate body area for salient versus non-salient images of bodies. Older adults showed no such advantage in selective processing under arousal. These age differences could not be attributed to changes in the arousal response or less neural distinctiveness in old age. Rather, our results suggest that, relative to young adults, older adults become less effective at focusing on salient over non-salient details during increases in emotional arousal.

neuroscience↗