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  1. Article ; Online: Vascular neuro-otology: vestibular transient ischemic attacks and chronic dizziness in the elderly.

    Bronstein, Adolfo M / Kattah, Jorge

    Current opinion in neurology

    2023  Volume 37, Issue 1, Page(s) 59–65

    Abstract: Purpose of review: To explore the differential diagnosis of posterior fossa transient ischemic attacks (TIA) associated with vertigo and/or imbalance.To review the contribution of cerebral small vessel (SVD) disease to balance dysfunction and dizziness ... ...

    Abstract Purpose of review: To explore the differential diagnosis of posterior fossa transient ischemic attacks (TIA) associated with vertigo and/or imbalance.To review the contribution of cerebral small vessel (SVD) disease to balance dysfunction and dizziness in the elderly.
    Main findings: TIAs involving vestibular structures that mediate the vestibulo-ocular and vestibulospinal reflexes remain a diagnostic challenge because they overlap with causes of benign episodic vertigo. Here, we summarize the results of multidisciplinary specialty efforts to improve timely recognition and intervention of peripheral and central vestibular ischemia. More papers confirm that SVD is a major cause of gait disability, falls and cognitive disorder in the elderly. Recent work shows that early stages of SVD may also be responsible for dizziness in the elderly. The predominant location of the white matter changes, in the frontal deep white matter and genu of the corpus callosum, explains the association between cognitive and balance dysfunction in SVD related symptoms.
    Summary: The evaluation of patients with intermittent vascular vertigo represent a major diagnostic challenge, recent reviews explore the ideal design approach for a multidisciplinary study to increase early recognition and intervention. Hemispheric white matter microvascular ischemia has been the subject of research progress - advanced stages are known to cause gait disorder and dementia but early stages are associated with "idiopathic" dizziness in the elderly.
    MeSH term(s) Humans ; Aged ; Dizziness/diagnosis ; Dizziness/etiology ; Ischemic Attack, Transient/complications ; Ischemic Attack, Transient/diagnosis ; Neurotology ; Vertigo/diagnosis ; Vertigo/etiology ; Ischemia/complications
    Language English
    Publishing date 2023-11-30
    Publishing country England
    Document type Review ; Journal Article
    ZDB-ID 1182686-1
    ISSN 1473-6551 ; 1350-7540
    ISSN (online) 1473-6551
    ISSN 1350-7540
    DOI 10.1097/WCO.0000000000001229
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Book ; Online: Setting the Record Straight on Transformer Oversmoothing

    Dovonon, Gbètondji J-S / Bronstein, Michael M. / Kusner, Matt J.

    2024  

    Abstract: Transformer-based models have recently become wildly successful across a diverse set of domains. At the same time, recent work has shown that Transformers are inherently low-pass filters that gradually oversmooth the inputs, reducing the expressivity of ... ...

    Abstract Transformer-based models have recently become wildly successful across a diverse set of domains. At the same time, recent work has shown that Transformers are inherently low-pass filters that gradually oversmooth the inputs, reducing the expressivity of their representations. A natural question is: How can Transformers achieve these successes given this shortcoming? In this work we show that in fact Transformers are not inherently low-pass filters. Instead, whether Transformers oversmooth or not depends on the eigenspectrum of their update equations. Our analysis extends prior work in oversmoothing and in the closely-related phenomenon of rank collapse. We show that many successful Transformer models have attention and weights which satisfy conditions that avoid oversmoothing. Based on this analysis, we derive a simple way to parameterize the weights of the Transformer update equations that allows for control over its spectrum, ensuring that oversmoothing does not occur. Compared to a recent solution for oversmoothing, our approach improves generalization, even when training with more layers, fewer datapoints, and data that is corrupted.
    Keywords Computer Science - Machine Learning
    Publishing date 2024-01-08
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: The influence of postural threat-induced anxiety on locomotor learning and updating.

    Ellmers, Toby J / Durkin, Morgan / Sriranganathan, Karthigan / Harris, David J / Bronstein, Adolfo M

    Journal of neurophysiology

    2024  Volume 131, Issue 3, Page(s) 562–575

    Abstract: The ability to adapt our locomotion in a feedforward (i.e., "predictive") manner is crucial for safe and efficient walking behavior. Equally important is the ability to quickly deadapt and update behavior that is no longer appropriate for the given ... ...

    Abstract The ability to adapt our locomotion in a feedforward (i.e., "predictive") manner is crucial for safe and efficient walking behavior. Equally important is the ability to quickly deadapt and update behavior that is no longer appropriate for the given context. It has been suggested that anxiety induced via postural threat may play a fundamental role in disrupting such deadaptation. We tested this hypothesis, using the "broken escalator" phenomenon: Fifty-six healthy young adults walked onto a stationary walkway ("BEFORE" condition, 5 trials), then onto a moving walkway akin to an airport travelator ("MOVING" condition, 10 trials), and then again onto the stationary walkway ("AFTER" condition, 5 trials). Participants completed all trials while wearing a virtual reality headset, which was used to induce postural threat-related anxiety (raised clifflike drop at the end of the walkway) during different phases of the paradigm. We found that performing the locomotor adaptation phase in a state of increased threat disrupted subsequent deadaptation during AFTER trials: These participants displayed anticipatory muscular activity as if expecting the platform to move and exhibited inappropriate anticipatory forward trunk movement that persisted during multiple AFTER trials. In contrast, postural threat induced during AFTER trials did not affect behavioral or neurophysiological outcomes. These findings highlight that actions learned in the presence of postural threat-induced anxiety are strengthened, leading to difficulties in deadapting these behaviors when no longer appropriate. Given the associations between anxiety and persistent maladaptive gait behaviors (e.g., "overly cautious" gait, functional gait disorders), the findings have implications for the understanding of such conditions.
    MeSH term(s) Young Adult ; Humans ; Walking/physiology ; Learning/physiology ; Gait/physiology ; Locomotion/physiology ; Anxiety ; Postural Balance/physiology
    Language English
    Publishing date 2024-02-07
    Publishing country United States
    Document type Journal Article
    ZDB-ID 80161-6
    ISSN 1522-1598 ; 0022-3077
    ISSN (online) 1522-1598
    ISSN 0022-3077
    DOI 10.1152/jn.00364.2023
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Dissociated cerebellar contributions to feedforward gait adaptation.

    Bunday, Karen L / Ellmers, Toby J / Wimalaratna, M Rashmi / Nadarajah, Luxme / Bronstein, Adolfo M

    Experimental brain research

    2024  

    Abstract: The cerebellum is important for motor adaptation. Lesions to the vestibulo-cerebellum selectively cause gait ataxia. Here we investigate how such damage affects locomotor adaptation when performing the 'broken escalator' paradigm. Following an auditory ... ...

    Abstract The cerebellum is important for motor adaptation. Lesions to the vestibulo-cerebellum selectively cause gait ataxia. Here we investigate how such damage affects locomotor adaptation when performing the 'broken escalator' paradigm. Following an auditory cue, participants were required to step from the fixed surface onto a moving platform (akin to an airport travellator). The experiment included three conditions: 10 stationary (BEFORE), 15 moving (MOVING) and 10 stationary (AFTER) trials. We assessed both behavioural (gait approach velocity and trunk sway after stepping onto the moving platform) and neuromuscular outcomes (lower leg muscle activity, EMG). Unlike controls, cerebellar patients showed reduced after-effects (AFTER trials) with respect to gait approach velocity and leg EMG activity. However, patients with cerebellar damage maintain the ability to learn the trunk movement required to maximise stability after stepping onto the moving platform (i.e., reactive postural behaviours). Importantly, our findings reveal that these patients could even initiate these behaviours in a feedforward manner, leading to an after-effect. These findings reveal that the cerebellum is crucial for feedforward locomotor control, but that adaptive locomotor behaviours learned via feedback (i.e., reactive) mechanisms may be preserved following cerebellum damage.
    Language English
    Publishing date 2024-05-17
    Publishing country Germany
    Document type Journal Article
    ZDB-ID 1201-4
    ISSN 1432-1106 ; 0014-4819
    ISSN (online) 1432-1106
    ISSN 0014-4819
    DOI 10.1007/s00221-024-06840-9
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article ; Online: Factors influencing clinical outcome in vestibular neuritis - A focussed review and reanalysis of prospective data.

    Arshad, Q / Cousins, S / Golding, J F / Bronstein, A M

    Journal of the neurological sciences

    2023  Volume 446, Page(s) 120579

    Abstract: Following vestibular neuritis (VN), long term prognosis is not dependent on the magnitude of the residual peripheral function as measured with either caloric or the video head-impulse test. Rather, recovery is determined by a combination of visuo- ... ...

    Abstract Following vestibular neuritis (VN), long term prognosis is not dependent on the magnitude of the residual peripheral function as measured with either caloric or the video head-impulse test. Rather, recovery is determined by a combination of visuo-vestibular (visual dependence), psychological (anxiety) and vestibular perceptual factors. Our recent research in healthy individuals has also revealed a strong association between the degree of lateralisation of vestibulo-cortical processing and gating of vestibular signals, anxiety and visual dependence. In the context of several functional brain changes occurring in the interaction between visual, vestibular and emotional cortices, which underpin the aforementioned psycho-physiological features in patients with VN, we re-examined our previously published findings focusing on additional factors impacting long term clinical outcome and function. These included: (i) the role of concomitant neuro-otological dysfunction (i.e. migraine and benign paroxysmal positional vertigo (BPPV)) and (ii) the degree to which brain lateralisation of vestibulo-cortical processing influences gating of vestibular function in the acute stage. We found that migraine and BPPV interfere with symptomatic recovery following VN. That is, dizziness handicap at short-term recovery stage was significantly predicted by migraine (r = 0.523, n = 28, p = .002), BPPV (r = 0.658, n = 31, p < .001) and acute visual dependency (r = 0.504, n = 28, p = .003). Moreover, dizziness handicap in the long-term recovery stage continued to be predicted by migraine (r = 0.640, n = 22, p = .001), BPPV (r = 0.626, n = 24, p = .001) and acute visual dependency (r = 0.667, n = 22, p < .001). Furthermore, surrogate measures of vestibulo-cortical lateralisation were predictive of the amount of cortical suppression exerted over vestibular thresholds. That is, in right-sided VN patients, we observed a positive correlation between visual dependence and acute ipsilesional oculomotor thresholds (R
    MeSH term(s) Humans ; Vestibular Neuronitis ; Dizziness/complications ; Prospective Studies ; Vertigo/complications ; Migraine Disorders/complications
    Language English
    Publishing date 2023-02-03
    Publishing country Netherlands
    Document type Journal Article
    ZDB-ID 80160-4
    ISSN 1878-5883 ; 0022-510X ; 0374-8642
    ISSN (online) 1878-5883
    ISSN 0022-510X ; 0374-8642
    DOI 10.1016/j.jns.2023.120579
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article: A pooled-sample draft genome assembly provides insights into host plant-specific transcriptional responses of a Solanaceae-specializing pest,

    Goldberg, Jay K / Allan, Carson W / Copetti, Dario / Matzkin, Luciano M / Bronstein, Judith

    Ecology and evolution

    2024  Volume 14, Issue 3, Page(s) e10979

    Abstract: The assembly of genomes from pooled samples of genetically heterogenous samples of conspecifics remains challenging. In this study, we show that high-quality genome assemblies can be produced from samples of multiple wild-caught individuals. We sequenced ...

    Abstract The assembly of genomes from pooled samples of genetically heterogenous samples of conspecifics remains challenging. In this study, we show that high-quality genome assemblies can be produced from samples of multiple wild-caught individuals. We sequenced DNA extracted from a pooled sample of conspecific herbivorous insects (Hemiptera: Miridae:
    Language English
    Publishing date 2024-03-11
    Publishing country England
    Document type Journal Article
    ZDB-ID 2635675-2
    ISSN 2045-7758
    ISSN 2045-7758
    DOI 10.1002/ece3.10979
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  7. Article ; Online: Agricultural paraquat dichloride use and Parkinson's disease in California's Central Valley.

    Paul, Kimberly C / Cockburn, Myles / Gong, Yufan / Bronstein, Jeff / Ritz, Beate

    International journal of epidemiology

    2024  Volume 53, Issue 1

    Abstract: Background: Paraquat dichloride is currently among the most widely used commercial herbicides in the USA. In the present study, we provide epidemiological assessment of ambient paraquat exposure and Parkinson's disease (PD) risk in a population-based ... ...

    Abstract Background: Paraquat dichloride is currently among the most widely used commercial herbicides in the USA. In the present study, we provide epidemiological assessment of ambient paraquat exposure and Parkinson's disease (PD) risk in a population-based study of PD in agricultural regions of Central California.
    Methods: Based on 829 PD patients and 824 community controls, we assessed associations between ambient paraquat dichloride exposure and PD. We estimated residential and workplace proximity to commercial agricultural applications in three California counties since 1974 using the CA pesticide use reporting (PUR) data and land use maps. We evaluated any, duration and average intensity [pounds (0.45 kilograms) per acre per year] of exposure for paraquat in four time windows.
    Results: Ambient paraquat exposure assessed at both residence and workplace was associated with PD, based on several different exposure measures. The PD patients both lived and worked near agricultural facilities applying greater amounts of the herbicide than community controls. For workplace proximity to commercial applications since 1974, working near paraquat applications every year in the window [odds ratio (OR) = 2.15, 95% confidence interval (CI) = 1.46, 3.19] and a higher average intensity of exposure [per 10 pounds (4.54 kilograms), OR = 2.08, 95% CI = 1.31, 3.38] were both associated with an increased odds of PD. Similar associations were observed for residential proximity (duration: OR = 1.91, 95% CI = 1.30, 2.83; average intensity: OR = 1.72, 95% CI = 0.99, 3.04). Risk estimates were comparable for men and women, and the strongest odds were observed for those diagnosed at ≤60 years of age.
    Conclusion: This study provides further indication that paraquat dichloride exposure increases the risk of Parkinson's disease.
    MeSH term(s) Male ; Humans ; Female ; Parkinson Disease/epidemiology ; Paraquat ; Pesticides ; Agriculture ; Disease Susceptibility ; California/epidemiology
    Chemical Substances Paraquat (PLG39H7695) ; Pesticides
    Language English
    Publishing date 2024-02-01
    Publishing country England
    Document type Journal Article
    ZDB-ID 187909-1
    ISSN 1464-3685 ; 0300-5771
    ISSN (online) 1464-3685
    ISSN 0300-5771
    DOI 10.1093/ije/dyae004
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article ; Online: Gene regulation by gonadal hormone receptors underlies brain sex differences.

    Gegenhuber, B / Wu, M V / Bronstein, R / Tollkuhn, J

    Nature

    2022  Volume 606, Issue 7912, Page(s) 153–159

    Abstract: Oestradiol establishes neural sex differences in many ... ...

    Abstract Oestradiol establishes neural sex differences in many vertebrates
    MeSH term(s) Animals ; Brain/metabolism ; Estradiol/metabolism ; Estrogen Receptor alpha/metabolism ; Female ; Gene Expression Regulation ; Male ; Mice ; Sex Characteristics
    Chemical Substances Estrogen Receptor alpha ; Estradiol (4TI98Z838E)
    Language English
    Publishing date 2022-05-04
    Publishing country England
    Document type Journal Article
    ZDB-ID 120714-3
    ISSN 1476-4687 ; 0028-0836
    ISSN (online) 1476-4687
    ISSN 0028-0836
    DOI 10.1038/s41586-022-04686-1
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article: Lysosomal genes contribute to Parkinson's disease near agriculture with high intensity pesticide use.

    Ngo, Kathie J / Paul, Kimberly C / Wong, Darice / Kusters, Cynthia D J / Bronstein, Jeff M / Ritz, Beate / Fogel, Brent L

    NPJ Parkinson's disease

    2024  Volume 10, Issue 1, Page(s) 87

    Abstract: Parkinson's disease (PD), the second most common neurodegenerative disorder, develops sporadically, likely through a combination of polygenic and environmental factors. Previous studies associate pesticide exposure and genes involved in lysosomal ... ...

    Abstract Parkinson's disease (PD), the second most common neurodegenerative disorder, develops sporadically, likely through a combination of polygenic and environmental factors. Previous studies associate pesticide exposure and genes involved in lysosomal function with PD risk. We evaluated the frequency of variants in lysosomal function genes among patients from the Parkinson's, Environment, and Genes (PEG) study with ambient pesticide exposure from agricultural sources. 757 PD patients, primarily of White European/non-Hispanic ancestry (75%), were screened for variants in 85 genes using a custom amplicon panel. Variant enrichment was calculated against the Genome Aggregation Database (gnomAD). Enriched exonic variants were prioritized by exposure to a cluster of pesticides used on cotton and severity of disease progression in a subset of 386 patients subdivided by race/ethnicity. Gene enrichment analysis identified 36 variants in 26 genes in PEG PD patients. Twelve of the identified genes (12/26, 46%) had multiple enriched variants and/or a single enriched variant present in multiple individuals, representing 61% (22/36) of the observed variation in the cohort. The majority of enriched variants (26/36, 72%) were found in genes contributing to lysosomal function, particularly autophagy, and were bioinformatically deemed functionally deleterious (31/36, 86%). We conclude that, in this study, variants in genes associated with lysosomal function, notably autophagy, were enriched in PD patients exposed to agricultural pesticides suggesting that altered lysosomal function may generate an underlying susceptibility for developing PD with pesticide exposure. Further study of gene-environment interactions targeting lysosomal function may improve understanding of PD risk in individuals exposed to pesticides.
    Language English
    Publishing date 2024-04-25
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2819218-7
    ISSN 2373-8057
    ISSN 2373-8057
    DOI 10.1038/s41531-024-00703-4
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Book ; Online: Curvature Filtrations for Graph Generative Model Evaluation

    Southern, Joshua / Wayland, Jeremy / Bronstein, Michael / Rieck, Bastian

    2023  

    Abstract: Graph generative model evaluation necessitates understanding differences between graphs on the distributional level. This entails being able to harness salient attributes of graphs in an efficient manner. Curvature constitutes one such property of graphs, ...

    Abstract Graph generative model evaluation necessitates understanding differences between graphs on the distributional level. This entails being able to harness salient attributes of graphs in an efficient manner. Curvature constitutes one such property of graphs, and has recently started to prove useful in characterising graphs. Its expressive properties, stability, and practical utility in model evaluation remain largely unexplored, however. We combine graph curvature descriptors with emerging methods from topological data analysis to obtain robust, expressive descriptors for evaluating graph generative models.
    Keywords Computer Science - Machine Learning ; Mathematics - Algebraic Topology ; Statistics - Machine Learning
    Publishing date 2023-01-30
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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