Darius Häusler, Sebastian Torke, E. Peelen, T. Bertsch, M. Djukic, R. Nau, C. Larochelle, S. Zamvil, W. Brück, Martin S. Weber
1 Institute of Neuropathology, University Medical Center, Göttingen, Germany 2 Department of Neurosciences, Centre de recherche de l’Université de Montréal (CRCHUM), Montréal, Québec, Canada 3 Institute of Clinical Chemistry, Laboratory Medicine and Transfusion Medicine, General Hospital Nuremberg, Paracelsus Medical University, Nuremberg, Germany 4 Department of Geriatrics, Evangelisches Krankenhaus Göttingen-Weende, Göttingen, Germany 5 Department of Neurology, University of California, San Francisco, CA, USA 6 Department of Neurology, University Medical Center, Göttingen, Germany
{"title":"Reply: Hypercalcaemia rather than high dose vitamin D3 supplements could exacerbate multiple sclerosis.","authors":"Darius Häusler, Sebastian Torke, E. Peelen, T. Bertsch, M. Djukic, R. Nau, C. Larochelle, S. Zamvil, W. Brück, Martin S. Weber","doi":"10.1093/brain/awz341","DOIUrl":"https://doi.org/10.1093/brain/awz341","url":null,"abstract":"1 Institute of Neuropathology, University Medical Center, Göttingen, Germany 2 Department of Neurosciences, Centre de recherche de l’Université de Montréal (CRCHUM), Montréal, Québec, Canada 3 Institute of Clinical Chemistry, Laboratory Medicine and Transfusion Medicine, General Hospital Nuremberg, Paracelsus Medical University, Nuremberg, Germany 4 Department of Geriatrics, Evangelisches Krankenhaus Göttingen-Weende, Göttingen, Germany 5 Department of Neurology, University of California, San Francisco, CA, USA 6 Department of Neurology, University Medical Center, Göttingen, Germany","PeriodicalId":121505,"journal":{"name":"Brain : a journal of neurology","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127886355","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. Herting, Zhihong Chen, V. Maximov, Alyssa Duffy, Frank Szulzewsky, D. Shayakhmetov, D. Hambardzumyan
Glioblastoma is the most common and uncompromising primary brain tumour and is characterized by a dismal prognosis despite aggressive treatment regimens. At the cellular level, these tumours are composed of a mixture of neoplastic cells and non-neoplastic cells, including tumour-associated macrophages and endothelial cells. Cerebral oedema is a near-universal occurrence in patients afflicted with glioblastoma and it is almost exclusively managed with the corticosteroid dexamethasone despite significant drawbacks associated with its use. Here, we demonstrate that dexamethasone blocks interleukin-1 production in both bone marrow-derived and brain resident macrophage populations following stimulation with lipopolysaccharide and interferon gamma. Additionally, dexamethasone is shown to inhibit downstream effectors of interleukin-1 signalling in both macrophage populations. Co-culture of bone marrow-derived macrophages with organotypic tumour slices results in an upregulation of interleukin-1 cytokines, an effect that is absent in co-cultured microglia. Genetic ablation of interleukin-1 ligands or receptor in mice bearing RCAS/tv-a-induced platelet-derived growth factor B-overexpressing glioblastoma results in reduced oedema and partial restoration of the integrity of the blood-brain barrier, respectively; similar to results obtained with vascular endothelial growth factor neutralization. We establish that tumours from dexamethasone-treated mice exhibit reduced infiltration of cells of the myeloid and lymphoid compartments, an effect that should be considered during clinical trials for immunotherapy in glioblastoma patients. Additionally, we emphasize that caution should be used when immune profiling and single-cell RNA sequencing data are interpreted from fresh glioblastoma patient samples, as nearly all patients receive dexamethasone after diagnosis. Collectively, this evidence suggests that interleukin-1 signalling inhibition and dexamethasone treatment share therapeutic efficacies and establishes interleukin-1 signalling as an attractive and specific therapeutic target for the management of glioblastoma-associated cerebral oedema.
{"title":"Tumour-associated macrophage-derived interleukin-1 mediates glioblastoma-associated cerebral oedema.","authors":"C. Herting, Zhihong Chen, V. Maximov, Alyssa Duffy, Frank Szulzewsky, D. Shayakhmetov, D. Hambardzumyan","doi":"10.1093/brain/awz331","DOIUrl":"https://doi.org/10.1093/brain/awz331","url":null,"abstract":"Glioblastoma is the most common and uncompromising primary brain tumour and is characterized by a dismal prognosis despite aggressive treatment regimens. At the cellular level, these tumours are composed of a mixture of neoplastic cells and non-neoplastic cells, including tumour-associated macrophages and endothelial cells. Cerebral oedema is a near-universal occurrence in patients afflicted with glioblastoma and it is almost exclusively managed with the corticosteroid dexamethasone despite significant drawbacks associated with its use. Here, we demonstrate that dexamethasone blocks interleukin-1 production in both bone marrow-derived and brain resident macrophage populations following stimulation with lipopolysaccharide and interferon gamma. Additionally, dexamethasone is shown to inhibit downstream effectors of interleukin-1 signalling in both macrophage populations. Co-culture of bone marrow-derived macrophages with organotypic tumour slices results in an upregulation of interleukin-1 cytokines, an effect that is absent in co-cultured microglia. Genetic ablation of interleukin-1 ligands or receptor in mice bearing RCAS/tv-a-induced platelet-derived growth factor B-overexpressing glioblastoma results in reduced oedema and partial restoration of the integrity of the blood-brain barrier, respectively; similar to results obtained with vascular endothelial growth factor neutralization. We establish that tumours from dexamethasone-treated mice exhibit reduced infiltration of cells of the myeloid and lymphoid compartments, an effect that should be considered during clinical trials for immunotherapy in glioblastoma patients. Additionally, we emphasize that caution should be used when immune profiling and single-cell RNA sequencing data are interpreted from fresh glioblastoma patient samples, as nearly all patients receive dexamethasone after diagnosis. Collectively, this evidence suggests that interleukin-1 signalling inhibition and dexamethasone treatment share therapeutic efficacies and establishes interleukin-1 signalling as an attractive and specific therapeutic target for the management of glioblastoma-associated cerebral oedema.","PeriodicalId":121505,"journal":{"name":"Brain : a journal of neurology","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131102253","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This scientific commentary refers to ‘Exacerbation of C1q dysregulation, synaptic loss and memory deficits in tau pathology linked to neuronal adenosine A2A receptors’, by Carvalho et al. (doi:10.1093/brain/awz288).
{"title":"Overactivity of neuronal adenosine A2A receptors accelerates neurodegeneration.","authors":"R. Cunha","doi":"10.1093/brain/awz335","DOIUrl":"https://doi.org/10.1093/brain/awz335","url":null,"abstract":"This scientific commentary refers to ‘Exacerbation of C1q dysregulation, synaptic loss and memory deficits in tau pathology linked to neuronal adenosine A2A receptors’, by Carvalho et al. (doi:10.1093/brain/awz288).","PeriodicalId":121505,"journal":{"name":"Brain : a journal of neurology","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123795941","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Editorial.","authors":"D. Kullmann","doi":"10.1093/brain/awz334","DOIUrl":"https://doi.org/10.1093/brain/awz334","url":null,"abstract":"","PeriodicalId":121505,"journal":{"name":"Brain : a journal of neurology","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134398753","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Mosley, Saee Paliwal, Katherine Robinson, T. Coyne, P. Silburn, M. Tittgemeyer, K. Stephan, M. Breakspear, Alistair Perry
Impulsivity in Parkinson's disease may be mediated by faulty evaluation of rewards or the failure to inhibit inappropriate choices. Despite prior work suggesting that distinct neural networks underlie these cognitive operations, there has been little study of these networks in Parkinson's disease, and their relationship to inter-individual differences in impulsivity. High-resolution diffusion MRI data were acquired from 57 individuals with Parkinson's disease (19 females, mean age 62, mean Hoehn and Yahr stage 2.6) prior to surgery for deep brain stimulation. Reward evaluation and response inhibition networks were reconstructed with seed-based probabilistic tractography. Impulsivity was evaluated using two approaches: (i) neuropsychiatric instruments were used to assess latent constructs of impulsivity, including trait impulsiveness and compulsivity, disinhibition, and also impatience; and (ii) participants gambled in an ecologically-valid virtual casino to obtain a behavioural read-out of explorative, risk-taking, impulsive behaviour. Multivariate analyses revealed that different components of impulsivity were associated with distinct variations in structural connectivity, implicating both reward evaluation and response inhibition networks. Larger bet sizes in the virtual casino were associated with greater connectivity of the reward evaluation network, particularly bilateral fibre tracts between the ventral striatum and ventromedial prefrontal cortex. In contrast, weaker connectivity of the response inhibition network was associated with increased exploration of alternative slot machines in the virtual casino, with right-hemispheric tracts between the subthalamic nucleus and the pre-supplementary motor area contributing most strongly. Further, reduced connectivity of the reward evaluation network was associated with more 'double or nothing' gambles, weighted by connections between the subthalamic nucleus and ventromedial prefrontal cortex. Notably, the variance explained by structural connectivity was higher for behavioural indices of impulsivity, derived from clinician-administered tasks and the gambling paradigm, as compared to questionnaire data. Lastly, a clinically-meaningful distinction could be made amongst participants with a history of impulse control behaviours based on the interaction of their network connectivity with medication dosage and gambling behaviour. In summary, we report structural brain-behaviour covariation in Parkinson's disease with distinct reward evaluation and response inhibition networks that underlie dissociable aspects of impulsivity (cf. choosing and stopping). More broadly, our findings demonstrate the potential of using naturalistic paradigms and neuroimaging techniques in clinical settings to assist in the identification of those susceptible to harmful behaviours.
{"title":"The structural connectivity of discrete networks underlies impulsivity and gambling in Parkinson's disease.","authors":"P. Mosley, Saee Paliwal, Katherine Robinson, T. Coyne, P. Silburn, M. Tittgemeyer, K. Stephan, M. Breakspear, Alistair Perry","doi":"10.1093/brain/awz327","DOIUrl":"https://doi.org/10.1093/brain/awz327","url":null,"abstract":"Impulsivity in Parkinson's disease may be mediated by faulty evaluation of rewards or the failure to inhibit inappropriate choices. Despite prior work suggesting that distinct neural networks underlie these cognitive operations, there has been little study of these networks in Parkinson's disease, and their relationship to inter-individual differences in impulsivity. High-resolution diffusion MRI data were acquired from 57 individuals with Parkinson's disease (19 females, mean age 62, mean Hoehn and Yahr stage 2.6) prior to surgery for deep brain stimulation. Reward evaluation and response inhibition networks were reconstructed with seed-based probabilistic tractography. Impulsivity was evaluated using two approaches: (i) neuropsychiatric instruments were used to assess latent constructs of impulsivity, including trait impulsiveness and compulsivity, disinhibition, and also impatience; and (ii) participants gambled in an ecologically-valid virtual casino to obtain a behavioural read-out of explorative, risk-taking, impulsive behaviour. Multivariate analyses revealed that different components of impulsivity were associated with distinct variations in structural connectivity, implicating both reward evaluation and response inhibition networks. Larger bet sizes in the virtual casino were associated with greater connectivity of the reward evaluation network, particularly bilateral fibre tracts between the ventral striatum and ventromedial prefrontal cortex. In contrast, weaker connectivity of the response inhibition network was associated with increased exploration of alternative slot machines in the virtual casino, with right-hemispheric tracts between the subthalamic nucleus and the pre-supplementary motor area contributing most strongly. Further, reduced connectivity of the reward evaluation network was associated with more 'double or nothing' gambles, weighted by connections between the subthalamic nucleus and ventromedial prefrontal cortex. Notably, the variance explained by structural connectivity was higher for behavioural indices of impulsivity, derived from clinician-administered tasks and the gambling paradigm, as compared to questionnaire data. Lastly, a clinically-meaningful distinction could be made amongst participants with a history of impulse control behaviours based on the interaction of their network connectivity with medication dosage and gambling behaviour. In summary, we report structural brain-behaviour covariation in Parkinson's disease with distinct reward evaluation and response inhibition networks that underlie dissociable aspects of impulsivity (cf. choosing and stopping). More broadly, our findings demonstrate the potential of using naturalistic paradigms and neuroimaging techniques in clinical settings to assist in the identification of those susceptible to harmful behaviours.","PeriodicalId":121505,"journal":{"name":"Brain : a journal of neurology","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129189184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
D. Weiss, Anna Schoellmann, M. Fox, N. Bohnen, S. Factor, A. Nieuwboer, M. Hallett, S. Lewis
Diverse but complementary methodologies are required to uncover the complex determinants and pathophysiology of freezing of gait. To develop future therapeutic avenues, we need a deeper understanding of the disseminated functional-anatomic network and its temporally associated dynamic processes. In this targeted review, we will summarize the latest advances across multiple methodological domains including clinical phenomenology, neurogenetics, multimodal neuroimaging, neurophysiology, and neuromodulation. We found that (i) locomotor network vulnerability is established by structural damage, e.g. from neurodegeneration possibly as result from genetic variability, or to variable degree from brain lesions. This leads to an enhanced network susceptibility, where (ii) modulators can both increase or decrease the threshold to express freezing of gait. Consequent to a threshold decrease, (iii) neuronal integration failure of a multilevel brain network will occur and affect one or numerous nodes and projections of the multilevel network. Finally, (iv) an ultimate pathway might encounter failure of effective motor output and give rise to freezing of gait as clinical endpoint. In conclusion, we derive key questions from this review that challenge this pathophysiological view. We suggest that future research on these questions should lead to improved pathophysiological insight and enhanced therapeutic strategies.
{"title":"Freezing of gait: understanding the complexity of an enigmatic phenomenon.","authors":"D. Weiss, Anna Schoellmann, M. Fox, N. Bohnen, S. Factor, A. Nieuwboer, M. Hallett, S. Lewis","doi":"10.1093/brain/awz314","DOIUrl":"https://doi.org/10.1093/brain/awz314","url":null,"abstract":"Diverse but complementary methodologies are required to uncover the complex determinants and pathophysiology of freezing of gait. To develop future therapeutic avenues, we need a deeper understanding of the disseminated functional-anatomic network and its temporally associated dynamic processes. In this targeted review, we will summarize the latest advances across multiple methodological domains including clinical phenomenology, neurogenetics, multimodal neuroimaging, neurophysiology, and neuromodulation. We found that (i) locomotor network vulnerability is established by structural damage, e.g. from neurodegeneration possibly as result from genetic variability, or to variable degree from brain lesions. This leads to an enhanced network susceptibility, where (ii) modulators can both increase or decrease the threshold to express freezing of gait. Consequent to a threshold decrease, (iii) neuronal integration failure of a multilevel brain network will occur and affect one or numerous nodes and projections of the multilevel network. Finally, (iv) an ultimate pathway might encounter failure of effective motor output and give rise to freezing of gait as clinical endpoint. In conclusion, we derive key questions from this review that challenge this pathophysiological view. We suggest that future research on these questions should lead to improved pathophysiological insight and enhanced therapeutic strategies.","PeriodicalId":121505,"journal":{"name":"Brain : a journal of neurology","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128778546","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Sandra Pusil, M. E. López, P. Cuesta, R. Bruña, E. Pereda, F. Maestú
Hypersynchronization has been proposed as a synaptic dysfunction biomarker in the Alzheimer's disease continuum, reflecting the alteration of the excitation/inhibition balance. While animal models have verified this idea extensively, there is still no clear evidence in humans. Here we test this hypothesis, evaluating the risk of conversion from mild cognitive impairment (MCI) to Alzheimer's disease in a longitudinal study. We compared the functional resting state eyes-closed magnetoencephalographic networks of 54 patients with MCI who were followed-up every 6 months. According to their clinical outcome, they were split into: (i) the 'progressive' MCI (n = 27) group; and (ii) the 'stable' MCI group (n = 27). They did not differ in gender or educational level. For all participants, two magnetoencephalographic recordings were acquired. Functional connectivity was evaluated using the phase locking value. To extract the functional connectivity network with significant changes between both magnetoencephalographic recordings, we evaluated the functional connectivity ratio, defined as functional connectivity post-/pre-condition, in a network-based statistical model with an ANCOVA test with age as covariate. Two significant networks were found in the theta and beta bands, involving fronto-temporal and fronto-occipital connections, and showing a diminished functional connectivity ratio in the progressive MCI group. These topologies were then evaluated at each condition showing that at baseline, patients with progressive MCI showed higher synchronization than patients with stable MCI, while in the post-condition this pattern was reversed. These results may be influenced by two main factors in the post-condition: the increased synchrony in the stable MCI patients and the network failure in the progressive MCI patients. These findings may be explained as an 'X' form model where the hypersynchrony predicts conversion, leading subsequently to a network breakdown in progressive MCI. Patients with stable MCI showed an opposite phenomenon, which could indicate that they were a step beyond in the Alzheimer's disease continuum. This model would be able to predict the risk for the conversion to dementia in MCI patients.
{"title":"Hypersynchronization in mild cognitive impairment: the 'X' model.","authors":"Sandra Pusil, M. E. López, P. Cuesta, R. Bruña, E. Pereda, F. Maestú","doi":"10.1093/brain/awz320","DOIUrl":"https://doi.org/10.1093/brain/awz320","url":null,"abstract":"Hypersynchronization has been proposed as a synaptic dysfunction biomarker in the Alzheimer's disease continuum, reflecting the alteration of the excitation/inhibition balance. While animal models have verified this idea extensively, there is still no clear evidence in humans. Here we test this hypothesis, evaluating the risk of conversion from mild cognitive impairment (MCI) to Alzheimer's disease in a longitudinal study. We compared the functional resting state eyes-closed magnetoencephalographic networks of 54 patients with MCI who were followed-up every 6 months. According to their clinical outcome, they were split into: (i) the 'progressive' MCI (n = 27) group; and (ii) the 'stable' MCI group (n = 27). They did not differ in gender or educational level. For all participants, two magnetoencephalographic recordings were acquired. Functional connectivity was evaluated using the phase locking value. To extract the functional connectivity network with significant changes between both magnetoencephalographic recordings, we evaluated the functional connectivity ratio, defined as functional connectivity post-/pre-condition, in a network-based statistical model with an ANCOVA test with age as covariate. Two significant networks were found in the theta and beta bands, involving fronto-temporal and fronto-occipital connections, and showing a diminished functional connectivity ratio in the progressive MCI group. These topologies were then evaluated at each condition showing that at baseline, patients with progressive MCI showed higher synchronization than patients with stable MCI, while in the post-condition this pattern was reversed. These results may be influenced by two main factors in the post-condition: the increased synchrony in the stable MCI patients and the network failure in the progressive MCI patients. These findings may be explained as an 'X' form model where the hypersynchrony predicts conversion, leading subsequently to a network breakdown in progressive MCI. Patients with stable MCI showed an opposite phenomenon, which could indicate that they were a step beyond in the Alzheimer's disease continuum. This model would be able to predict the risk for the conversion to dementia in MCI patients.","PeriodicalId":121505,"journal":{"name":"Brain : a journal of neurology","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114829354","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Quartarone, A. Cacciola, D. Milardi, M. Ghilardi, A. Calamuneri, G. Chillemi, G. Anastasi, J. Rothwell
The current model of the basal ganglia system based on the 'direct', 'indirect' and 'hyperdirect' pathways provides striking predictions about basal ganglia function that have been used to develop deep brain stimulation approaches for Parkinson's disease and dystonia. The aim of this review is to challenge this scheme in light of new tract tracing information that has recently become available from the human brain using MRI-based tractography, thus providing a novel perspective on the basal ganglia system. We also explore the implications of additional direct pathways running from cortex to basal ganglia and between basal ganglia and cerebellum in the pathophysiology of movement disorders.
{"title":"New insights into cortico-basal-cerebellar connectome: clinical and physiological considerations.","authors":"A. Quartarone, A. Cacciola, D. Milardi, M. Ghilardi, A. Calamuneri, G. Chillemi, G. Anastasi, J. Rothwell","doi":"10.1093/brain/awz310","DOIUrl":"https://doi.org/10.1093/brain/awz310","url":null,"abstract":"The current model of the basal ganglia system based on the 'direct', 'indirect' and 'hyperdirect' pathways provides striking predictions about basal ganglia function that have been used to develop deep brain stimulation approaches for Parkinson's disease and dystonia. The aim of this review is to challenge this scheme in light of new tract tracing information that has recently become available from the human brain using MRI-based tractography, thus providing a novel perspective on the basal ganglia system. We also explore the implications of additional direct pathways running from cortex to basal ganglia and between basal ganglia and cerebellum in the pathophysiology of movement disorders.","PeriodicalId":121505,"journal":{"name":"Brain : a journal of neurology","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121996723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
C. P. de Fuenmayor-Fernández de la Hoz, A. Hernández-Laín, M. Olivé, M. T. Sánchez-Calvín, J. F. Gonzalo-Martínez, C. Domínguez-González
{"title":"Adult-onset distal spinal muscular atrophy: a new phenotype associated with KIF5A mutations.","authors":"C. P. de Fuenmayor-Fernández de la Hoz, A. Hernández-Laín, M. Olivé, M. T. Sánchez-Calvín, J. F. Gonzalo-Martínez, C. Domínguez-González","doi":"10.1093/brain/awz317","DOIUrl":"https://doi.org/10.1093/brain/awz317","url":null,"abstract":"","PeriodicalId":121505,"journal":{"name":"Brain : a journal of neurology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123105153","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Fluctuating cognition is a complex and disabling symptom that is seen most frequently in the context of Lewy body dementias encompassing dementia with Lewy bodies and Parkinson's disease dementia. In fact, since their description over three decades ago, cognitive fluctuations have remained a core diagnostic feature of dementia with Lewy bodies, the second most common dementia in the elderly. In the absence of reliable biomarkers for Lewy body pathology, the inclusion of such patients in therapeutic trials depends on the accurate identification of such core clinical features. Yet despite their diagnostic relevance, cognitive fluctuations remain poorly understood, in part due to the lack of a cohesive clinical and scientific explanation of the phenomenon itself. Motivated by this challenge, the present review examines the history, clinical phenomenology and assessment of cognitive fluctuations in the Lewy body dementias. Based on these data, the key neuropsychological, neurophysiological and neuroimaging correlates of cognitive fluctuations are described and integrated into a novel testable heuristic framework from which new insights may be gained.
{"title":"Cognitive fluctuations in Lewy body dementia: towards a pathophysiological framework.","authors":"E. Matar, J. Shine, G. Halliday, S. Lewis","doi":"10.1093/brain/awz311","DOIUrl":"https://doi.org/10.1093/brain/awz311","url":null,"abstract":"Fluctuating cognition is a complex and disabling symptom that is seen most frequently in the context of Lewy body dementias encompassing dementia with Lewy bodies and Parkinson's disease dementia. In fact, since their description over three decades ago, cognitive fluctuations have remained a core diagnostic feature of dementia with Lewy bodies, the second most common dementia in the elderly. In the absence of reliable biomarkers for Lewy body pathology, the inclusion of such patients in therapeutic trials depends on the accurate identification of such core clinical features. Yet despite their diagnostic relevance, cognitive fluctuations remain poorly understood, in part due to the lack of a cohesive clinical and scientific explanation of the phenomenon itself. Motivated by this challenge, the present review examines the history, clinical phenomenology and assessment of cognitive fluctuations in the Lewy body dementias. Based on these data, the key neuropsychological, neurophysiological and neuroimaging correlates of cognitive fluctuations are described and integrated into a novel testable heuristic framework from which new insights may be gained.","PeriodicalId":121505,"journal":{"name":"Brain : a journal of neurology","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132677664","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}