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Leclaire KN, Blujus JK, Korthauer LE, Driscoll I. APOE4-related differences in cortical thickness are modulated by sex in middle age. Brain Imaging Behav 2024:10.1007/s11682-024-00911-9. [PMID: 39196521 DOI: 10.1007/s11682-024-00911-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 08/12/2024] [Indexed: 08/29/2024]
Abstract
Apolipoprotein E (APOE) ε4, the strongest genetic risk for late-onset Alzheimer's disease (AD), confers greater risk in females than males. While APOE4-related modulation of structural brain integrity in AD is well documented, extant literature on sex-APOE interactions has focused on older adults. The understanding of the healthy brain as a part of the normal aging process and as distinct from explicit disease or pathology is essential before comparison can be made with pathological states. Hence, it is crucial to characterize and better understand these relationships in middle-age prior to the onset of overt clinical symptoms and advanced neurodegeneration. The present study examined the relationships between sex, APOE status, and cortical thickness in 128 healthy, cognitively unimpaired, middle-aged adults (ages 40-60, M(SD) = 49.97(6.04); 77 females). All participants underwent structural magnetic resonance imaging and were genotyped for APOE (APOE4 + = 38; APOE4- = 90). Compared to males, females had thicker superior frontal cortices bilaterally, left middle temporal cortex, and left pars triangularis. APOE4 + had thinner left rostral middle frontal gyrus compared to APOE4-. Female compared to male APOE4- had thicker left banks of the superior temporal sulcus, left caudal anterior cingulate, left superior frontal, left superior parietal, and right precentral cortices. Female compared to male APOE4 + had thicker superior frontal cortices bilaterally. Female APOE4 + had thinner left rostral anterior cingulate cortex compared to female APOE4-. Overall, APOE-related differences in cortical thickness are more pronounced in females and detectable in middle age, well before the onset of overt clinical symptoms of AD.
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Affiliation(s)
- Kaitlynne N Leclaire
- Department of Psychology, University of Wisconsin-Milwaukee, 2441 E. Hartford Ave, Milwaukee, WI, 53211, USA
| | - Jenna K Blujus
- Department of Psychology, University of Wisconsin-Milwaukee, 2441 E. Hartford Ave, Milwaukee, WI, 53211, USA
| | - Laura E Korthauer
- Psychiatry and Human Behavior, Alpert Medical School of Brown University, Providence, RI, 02903, USA
| | - Ira Driscoll
- Department of Psychology, University of Wisconsin-Milwaukee, 2441 E. Hartford Ave, Milwaukee, WI, 53211, USA.
- Geriatrics and Gerontology, School of Medicine and Public Health, University of WI - Madison, Madison, WI, 53792, USA.
- Alzheimer's Disease Research Center, University of WI - Madison, J5/M192 Clinical Science Center, 00 Highland Avenue, Madison, WI, 53792, USA.
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2
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Rouse MA, Binney RJ, Patterson K, Rowe JB, Lambon Ralph MA. A neuroanatomical and cognitive model of impaired social behaviour in frontotemporal dementia. Brain 2024; 147:1953-1966. [PMID: 38334506 PMCID: PMC11146431 DOI: 10.1093/brain/awae040] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2023] [Revised: 12/21/2023] [Accepted: 01/21/2024] [Indexed: 02/10/2024] Open
Abstract
Impaired social cognition is a core deficit in frontotemporal dementia (FTD). It is most commonly associated with the behavioural-variant of FTD, with atrophy of the orbitofrontal and ventromedial prefrontal cortex. Social cognitive changes are also common in semantic dementia, with atrophy centred on the anterior temporal lobes. The impairment of social behaviour in FTD has typically been attributed to damage to the orbitofrontal cortex and/or temporal poles and/or the uncinate fasciculus that connects them. However, the relative contributions of each region are unresolved. In this review, we present a unified neurocognitive model of controlled social behaviour that not only explains the observed impairment of social behaviours in FTD, but also assimilates both consistent and potentially contradictory findings from other patient groups, comparative neurology and normative cognitive neuroscience. We propose that impaired social behaviour results from damage to two cognitively- and anatomically-distinct components. The first component is social-semantic knowledge, a part of the general semantic-conceptual system supported by the anterior temporal lobes bilaterally. The second component is social control, supported by the orbitofrontal cortex, medial frontal cortex and ventrolateral frontal cortex, which interacts with social-semantic knowledge to guide and shape social behaviour.
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Affiliation(s)
- Matthew A Rouse
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
| | - Richard J Binney
- Cognitive Neuroscience Institute, Department of Psychology, School of Human and Behavioural Sciences, Bangor University, Bangor LL57 2AS, UK
| | - Karalyn Patterson
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
- Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0SZ, UK
| | - James B Rowe
- MRC Cognition and Brain Sciences Unit, University of Cambridge, Cambridge CB2 7EF, UK
- Department of Clinical Neurosciences, University of Cambridge, Cambridge CB2 0SZ, UK
- Department of Neurology, Cambridge University Hospitals NHS Foundation Trust, Cambridge CB2 0SZ, UK
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3
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Feldner AC, Turner AK, Simpson JF, Estus S. Skipping of FCER1G Exon 2 Is Common in Human Brain But Not Associated with the Alzheimer's Disease Genetic Risk Factor rs2070902. J Alzheimers Dis Rep 2023; 7:1313-1322. [PMID: 38143775 PMCID: PMC10741965 DOI: 10.3233/adr-230076] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 10/30/2023] [Indexed: 12/26/2023] Open
Abstract
Background Understanding the mechanisms whereby genetic variants influence the risk of Alzheimer's disease (AD) may provide insights into treatments that could reduce AD risk. Objective Here, we sought to test the hypothesis that a single nucleotide polymorphism (SNP) associated with AD risk, rs2070902, influences splicing of FCER1G exon 2. Methods AD and non-AD brain samples were analyzed for FCER1G expression by genotyping, immunohistochemistry, immunofluorescence, and qPCR. Results The protein encoded by FCER1G, FcRγ, is robustly expressed in microglia in both AD and non-AD brain. The FCER1G isoform lacking exon 2 (D2-FCER1G) was readily detectable. Moreover, the proportion of FCER1G expressed as this isoform was increased in brains with high AD neuropathology. However, the proportion of FCER1G expressed as the D2-FCER1G isoform was not associated with rs2070902 genotype. Conclusions In summary, the proportion of FCER1G expressed as the D2-FCER1G isoform is increased with AD neuropathology but is not associated with rs2070902.
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Affiliation(s)
- Alyssa C. Feldner
- Department of Physiology and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Andrew K. Turner
- Department of Physiology and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - James F. Simpson
- Department of Physiology and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
| | - Steven Estus
- Department of Physiology and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY, USA
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4
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Zajac DJ, Simpson J, Zhang E, Parikh I, Estus S. Expression of INPP5D Isoforms in Human Brain: Impact of Alzheimer's Disease Neuropathology and Genetics. Genes (Basel) 2023; 14:763. [PMID: 36981033 PMCID: PMC10048252 DOI: 10.3390/genes14030763] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/10/2023] [Accepted: 03/15/2023] [Indexed: 03/30/2023] Open
Abstract
The single nucleotide polymorphisms rs35349669 and rs10933431 within Inositol Polyphosphate-5-Phosphatase D (INPP5D) are strongly associated with Alzheimer's Disease risk. To better understand INPP5D expression in the brain, we investigated INPP5D isoform expression as a function of rs35349669 and rs10933431, as well as Alzheimer's disease neuropathology, by qPCR and isoform-specific primers. In addition, INPP5D allelic expression imbalance was evaluated relative to rs1141328 within exon 1. Expression of INPP5D isoforms associated with transcription start sites in exon 1 and intron 14 was increased in individuals with high Alzheimer's disease neuropathology. In addition, a novel variant with 47bp lacking from exon 12 increased expression in Alzheimer's Disease brains, accounting for 13% of total INPP5D expression, and was found to undergo nonsense-mediated decay. Although inter-individual variation obscured a possible polymorphism effect on INPP5D isoform expression as measured by qPCR, rs35349669 was associated with rs1141328 allelic expression imbalance, suggesting that rs35349669 is significantly associated with full-length INPP5D isoform expression. In summary, expression of INPP5D isoforms with start sites in exon 1 and intron 14 are increased in brains with high Alzheimer's Disease neuropathology, a novel isoform lacking the phosphatase domain was significantly increased with the disease, and the polymorphism rs35349669 correlates with allele-specific full-length INPP5D expression.
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Affiliation(s)
| | | | | | | | - Steven Estus
- Department of Physiology and Sanders-Brown Center on Aging, University of Kentucky, Lexington, KY 40508, USA
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Zhang F, Rakhimbekova A, Lashley T, Madl T. Brain regions show different metabolic and protein arginine methylation phenotypes in frontotemporal dementias and Alzheimer's disease. Prog Neurobiol 2023; 221:102400. [PMID: 36581185 DOI: 10.1016/j.pneurobio.2022.102400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2022] [Revised: 11/05/2022] [Accepted: 12/19/2022] [Indexed: 12/27/2022]
Abstract
Frontotemporal dementia (FTD) is a heterogeneous neurodegenerative disease with multiple histopathological subtypes. FTD patients share similar symptoms with Alzheimer's disease (AD). Hence, FTD patients are commonly misdiagnosed as AD, despite the consensus clinical diagnostic criteria. It is therefore of great clinical need to identify a biomarker that can distinguish FTD from AD and control individuals, and potentially further differentiate between FTD pathological subtypes. We conducted a metabolomic analysis on post-mortem human brain tissue from three regions: cerebellum, frontal cortex and occipital cortex from control, FTLD-TDP type A, type A-C9, type C and AD. Our results indicate that the brain subdivisions responsible for different functions show different metabolic patterns. We further explored the region-specific metabolic characteristics of different FTD subtypes and AD patients. Different FTD subtypes and AD share similar metabolic phenotypes in the cerebellum, but AD exhibited distinct metabolic patterns in the frontal and occipital regions compared to FTD. The identified brain region-specific metabolite biomarkers could provide a tool for distinguishing different FTD subtypes and AD and provide the first insights into the metabolic changes of FTLD-TDP type A, type A-C9, type C and AD in different regions of the brain. The importance of protein arginine methylation in neurodegenerative disease has come to light, so we investigated whether the arginine methylation level contributes to disease pathogenesis. Our findings provide new insights into the relationship between arginine methylation and metabolic changes in FTD subtypes and AD that could be further explored, to study the molecular mechanism of pathogenesis.
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Affiliation(s)
- Fangrong Zhang
- Key Laboratory of Gastrointestinal Cancer (Fujian Medical University), Ministry of Education, Fuzhou, China; Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Research Unit Integrative Structural Biology, Medical University of Graz, 8010 Graz, Austria.
| | - Anastasia Rakhimbekova
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Research Unit Integrative Structural Biology, Medical University of Graz, 8010 Graz, Austria.
| | - Tammaryn Lashley
- Department of Neurodegenerative Disease, UCL Queen Square Institute of Neurology, London, UK; Queen Square Brain Bank for Neurological Diseases, UCL Queen Square Institute of Neurology, London, UK.
| | - Tobias Madl
- Gottfried Schatz Research Center for Cell Signaling, Metabolism and Aging, Molecular Biology and Biochemistry, Research Unit Integrative Structural Biology, Medical University of Graz, 8010 Graz, Austria; BioTechMed-Graz, 8010 Graz, Austria.
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6
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Zhang G, Liu T, Wei W, Zhang R, Wang H, Wang M. Evaluation of altered brain activity in type 2 diabetes using various indices of brain function: A resting-state functional magnetic resonance imaging study. Front Hum Neurosci 2023; 16:1032264. [PMID: 36699964 PMCID: PMC9870028 DOI: 10.3389/fnhum.2022.1032264] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 12/05/2022] [Indexed: 01/11/2023] Open
Abstract
Background Type 2 diabetes mellitus (T2DM) has been identified as a risk factor that increases the rate of cognitive decline. Previous studies showed that patients with T2DM had brain function alterations based on a single index of resting-state functional magnetic resonance imaging (rs-fMRI). The present study aimed to explore spontaneous brain activity in patients with T2DM by comparing various rs-fMRI indices, and to determine the relationship between these changes and cognitive dysfunction. Methods A total of 52 patients with T2DM and age- and sex-matched control participants were included in this study. The amplitude of low-frequency fluctuation (ALFF), regional homogeneity (ReHo), and voxel-mirrored homotopic connectivity (VMHC) values were calculated to represent the status of spontaneous neural activity. The Montreal Cognitive Assessment (MoCA) was used for the rapid evaluation of cognition in all subjects. Pearson correlation and mediation analyses were conducted to investigate the relationship between rs-fMRI indices and clinical parameters such as fasting glucose, disease duration, and MoCA. Results Patients with T2DM had alterations of concordant spontaneous brain activity in brain areas including the bilateral cerebellum posterior lobe, the left inferior temporal gyrus (ITG.L), the parahippocampal gyrus, and the left supplementary motor area (SMA.L). The indices were significantly correlated to each other in most of the detected brain areas. Positive correlations were observed between fasting glucose and neural activity in the surrounding areas of the left insula and the inferior frontal gyrus. MoCA scores were negatively correlated with the ReHo values extracted from the left anterior occipital lobe and the superior cerebellar cortex and were positively correlated with VMHC values extracted from the left caudate and the precentral gyrus (PreCG). No significant mediation effect of abnormal brain activity was found in the relationship between clinical parameters and MoCA scores. Conclusion The current study demonstrated the functional concordance of abnormal brain activities in patients with T2DM by comparing ALFF, ReHo, and VMHC measurements. Widespread abnormalities mainly involved in motor and sensory processing functions may provide insight into examining T2DM-related neurological pathophysiology.
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Affiliation(s)
- Ge Zhang
- Department of Radiology, Henan Provincial People's Hospital, Zhengzhou, China,Department of Radiology, Bethune International Peace Hospital, Shijiazhuang, China
| | - Taiyuan Liu
- Department of Radiology, Henan Provincial People's Hospital, Zhengzhou, China
| | - Wei Wei
- Department of Radiology, Henan Provincial People's Hospital, Zhengzhou, China
| | - Rui Zhang
- Department of Radiology, Henan Provincial People's Hospital, Zhengzhou, China
| | - Huilin Wang
- Department of Radiology, Bethune International Peace Hospital, Shijiazhuang, China,*Correspondence: Huilin Wang ✉
| | - Meiyun Wang
- Department of Radiology, Henan Provincial People's Hospital, Zhengzhou, China,Laboratory of Brian Science and Brain-Like Intelligence Technology, Institute for Integrated Medical Science and Engineering, Henan Academy of Sciences, Zhengzhou, China,Meiyun Wang ✉
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7
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Karimi F, Anari H, Yousefi Nejad A, Karbalay-Doust S, Naseh M. Post-weaning exposure to Sunset Yellow FCF induces behavioral impairment and structural changes in the adult rat medial prefrontal cortex: protective effects of Coenzyme Q10. Int J Dev Neurosci 2022; 82:303-313. [PMID: 35293019 DOI: 10.1002/jdn.10178] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Revised: 03/08/2022] [Accepted: 03/11/2022] [Indexed: 11/07/2022] Open
Abstract
Sunset Yellow FCF (E110) is a water soluble synthetic dye that has adverse neurobehavioral effects. Coenzyme Q10 (CoQ10) is known as a neuroprotective agent. The present study aimed to evaluate the effects of post-weaning exposure to Sunset Yellow FCF on behavioral and structural changes in the adult rat medial prefrontal cortex and the protective effects of CoQ10. The weanling rats were randomly divided into six groups: distilled water, CoQ10 (10 mg/kg/day), and low (2.5 mg/kg/day), and high (70 mg/kg/day) doses of Sunset Yellow FCF with or without CoQ10 consumption for six weeks. A battery of behavioral tests including open field and Morris water maze tests were done at the end of the 6th week, and then the animals' brains were removed for stereological methods. Our finding indicated that the high dose of Sunset Yellow FCF led to a reduced total volume of mPFC (15.16%), especially in the anterior cingulate cortex (ACC) region (21.96%), along with loss of neurons (32%) and glial cells (37%), which was associated with higher anxiety behavior and loss in spatial memory. However, CoQ10 prevented the neural loss and glial cells, improved anxiety like behaviors and memory impairment. On the other hand, the acceptable daily dose (low dose of Sunset Yellow FCF) did not show a discernible effect on the same parameters. This study showed that the CoQ10 can protect the alteration in mPFC structure and behavioral changes of the rats exposed to high dose of Sunset Yellow FCF.
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Affiliation(s)
- Fatemeh Karimi
- Histomorphometry and Stereology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.,Department of Anatomy, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Hamideh Anari
- Histomorphometry and Stereology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.,Department of Anatomy, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Amirhossein Yousefi Nejad
- Histomorphometry and Stereology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Saied Karbalay-Doust
- Histomorphometry and Stereology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.,Department of Anatomy, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Maryam Naseh
- Histomorphometry and Stereology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
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8
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Schwarck S, Busse N, Ziegler G, Glanz W, Becke A, Düzel E. Heart Rate Variability During Physical Exercise Is Associated With Improved Cognitive Performance in Alzheimer's Dementia Patients-A Longitudinal Feasibility Study. Front Sports Act Living 2021; 3:684089. [PMID: 34337405 PMCID: PMC8319237 DOI: 10.3389/fspor.2021.684089] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Accepted: 06/09/2021] [Indexed: 11/13/2022] Open
Abstract
Heart rate variability (HRV) rapidly gains attention as an important marker of cardiovascular autonomic modulation. Moreover, there is evidence for a link between the autonomic deficit measurable by reduced HRV and the hypoactivity of the cholinergic system, which is prominently affected in Alzheimer's disease (AD). Despite the positive influence of physical exercise on cognition and its promising association with HRV, previous studies did not explore the effect of long-term physical exercise in older adults with AD. Taking advantage of a longitudinal study we analyzed the effect of a 20-week dual task training regime (3 × 15-min per week) on the vagal mediated HRV index RMSSD (root mean square of successive RR interval differences) during physical exercise and the short-term memory performance in a AD cohort (N = 14). Each training contained physical exercise on a bicycle ergometer while memorizing 30 successively presented pictures as well as the associated post-exercise picture recognition memory test. Linear-mixed modeling revealed that HRV-RMSSD significantly increased over the intervention time. Moreover, the reaction time in the picture recognition task decreased while the accuracy remained stable. Furthermore, a significantly negative relationship between increased fitness measured by HRV-RMSSD and decreased reaction time was observed. This feasibility study points to the positive effects of a dual task regime on physical and cognitive fitness in a sample with impaired cognitive performance. Beyond this, the results show that the responsiveness of parasympathetic system as measured with HRV can be improved in patients with dementia.
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Affiliation(s)
- Svenja Schwarck
- Institute of Cognitive Neurology and Dementia Research, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.,German Center of Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Nancy Busse
- Institute of Cognitive Neurology and Dementia Research, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.,German Center of Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Gabriel Ziegler
- Institute of Cognitive Neurology and Dementia Research, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.,German Center of Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Wenzel Glanz
- Institute of Cognitive Neurology and Dementia Research, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.,German Center of Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Andreas Becke
- Institute of Cognitive Neurology and Dementia Research, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.,German Center of Neurodegenerative Diseases (DZNE), Magdeburg, Germany
| | - Emrah Düzel
- Institute of Cognitive Neurology and Dementia Research, Otto-von-Guericke-University Magdeburg, Magdeburg, Germany.,German Center of Neurodegenerative Diseases (DZNE), Magdeburg, Germany
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9
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Tan RH, Yang Y, McCann H, Shepherd C, Halliday GM. Von Economo Neurons in Behavioral Variant Frontotemporal Dementia with Underlying Alzheimer's Disease. J Alzheimers Dis 2020; 69:963-967. [PMID: 31104018 DOI: 10.3233/jad-180900] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The selective loss of von Economo neurons has been linked to the behavioral deficits in behavioral variant frontotemporal dementia (bvFTD) but whether these neurons are affected in bvFTD patients with underlying Alzheimer's disease (AD) has yet to be established. The present study assesses the von Economo neurons in pathological AD cases clinically diagnosed with either AD or bvFTD. Our results demonstrate no significant loss of von Economo neurons in all pathological AD cases, irrespective of clinical diagnosis or co-existing Lewy body pathology. These results suggest that the behavioral deficits in patients with clinical bvFTD and underlying pathological AD are not driven by the loss of von Economo neurons.
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Affiliation(s)
- Rachel H Tan
- The University of Sydney, Brain and Mind Centre and Central Clinical School, Faculty of Medicine and Health, Australia.,School of Medical Sciences, University of New South Wales, and Neuroscience Research Australia, Sydney, Australia
| | - Yue Yang
- The University of Sydney, Brain and Mind Centre and Central Clinical School, Faculty of Medicine and Health, Australia
| | - Heather McCann
- School of Medical Sciences, University of New South Wales, and Neuroscience Research Australia, Sydney, Australia
| | - Claire Shepherd
- School of Medical Sciences, University of New South Wales, and Neuroscience Research Australia, Sydney, Australia
| | - Glenda M Halliday
- The University of Sydney, Brain and Mind Centre and Central Clinical School, Faculty of Medicine and Health, Australia.,School of Medical Sciences, University of New South Wales, and Neuroscience Research Australia, Sydney, Australia
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Delvecchio G, Mandolini GM, Arighi A, Prunas C, Mauri CM, Pietroboni AM, Marotta G, Cinnante CM, Triulzi FM, Galimberti D, Scarpini E, Altamura AC, Brambilla P. Structural and metabolic cerebral alterations between elderly bipolar disorder and behavioural variant frontotemporal dementia: A combined MRI-PET study. Aust N Z J Psychiatry 2019; 53:413-423. [PMID: 30545239 DOI: 10.1177/0004867418815976] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
BACKGROUND Elderly bipolar disorder (BD) and behavioural variant of frontotemporal dementia (bvFTD) may exhibit similar symptoms and both disorders are characterized by selective abnormalities in cortical and subcortical regions that are associated with cognitive and emotional impairments. We aimed to investigate common and distinct neural substrates of BD and bvFTD by coupling, for the first time, magnetic resonance imaging (MRI) and positron emission tomography (PET) techniques. METHODS 3-Tesla MRI and 18 fluorodeoxyglucose-PET scans were acquired for 16 elderly BD patients, 23 bvFTD patients with mild cognitive impairments and 68 healthy controls (48 for PET and 20 for MRI analyses). RESULTS BD and bvFTD patients exhibit a different localization of grey matter reductions in the lateral prefrontal cortex, with the first group showing grey matter decrease in the ventrolateral prefrontal cortex and the latter group showing grey matter reductions in the dorsolateral prefrontal cortex as well as unique grey matter and metabolic alterations within the orbitofrontal cortex. The bvFTD group also displayed unique volumetric shrinkage in regions within the temporo-parietal network together with greater metabolic impairments within the temporal cortex and more extensive volumetric and metabolic abnormalities within the limbic lobe. Finally, while the BD group showed greater grey matter volumes in caudate nucleus, bvFTD subjects displayed lower metabolism. CONCLUSION This MRI-PET study explored, for the first time to the best of our knowledge, structural and functional abnormalities in bvFTD and elderly BD patients, with the final aim of identifying the specific biological signature of these disorders, which might have important implications not only in prevention but also in differential diagnosis and treatment.
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Affiliation(s)
- Giuseppe Delvecchio
- 1 Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy
| | - Gian Mario Mandolini
- 1 Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.,2 Department of Neurosciences and Mental Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Andrea Arighi
- 1 Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.,2 Department of Neurosciences and Mental Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,3 'Dino Ferrari' Center, Milan, Italy
| | - Cecilia Prunas
- 1 Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.,2 Department of Neurosciences and Mental Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Carlo Massimo Mauri
- 2 Department of Neurosciences and Mental Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Anna M Pietroboni
- 1 Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.,2 Department of Neurosciences and Mental Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,3 'Dino Ferrari' Center, Milan, Italy
| | - Giorgio Marotta
- 2 Department of Neurosciences and Mental Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Claudia Maria Cinnante
- 2 Department of Neurosciences and Mental Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Fabio Maria Triulzi
- 1 Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.,2 Department of Neurosciences and Mental Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Daniela Galimberti
- 1 Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.,2 Department of Neurosciences and Mental Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,3 'Dino Ferrari' Center, Milan, Italy
| | - Elio Scarpini
- 1 Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.,2 Department of Neurosciences and Mental Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy.,3 'Dino Ferrari' Center, Milan, Italy
| | - Alfredo Carlo Altamura
- 1 Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.,2 Department of Neurosciences and Mental Health, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Milan, Italy
| | - Paolo Brambilla
- 1 Department of Pathophysiology and Transplantation, University of Milan, Milan, Italy.,4 Department of Psychiatry and Behavioural Sciences, UT Houston Medical School, Houston, TX, USA
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11
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Touroutoglou A, Dickerson BC. Cingulate-centered large-scale networks: Normal functions, aging, and neurodegenerative disease. HANDBOOK OF CLINICAL NEUROLOGY 2019; 166:113-127. [PMID: 31731908 DOI: 10.1016/b978-0-444-64196-0.00008-x] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
In this chapter, we review evidence from structural and functional neuroimaging in humans to consider the role of the cingulate cortex subregions (i.e., subgenual anterior cingulate cortex, pregenual anterior cingulate cortex, anterior midcingulate cortex, and dorsal posterior cingulate cortex) as major hubs anchoring multiple large-scale brain networks. We begin with a review of evidence from intrinsic functional connectivity and diffusion tensor imaging studies to show how connections within and between cingulate-centered networks contribute to processing and integrating signals related to autonomic, affective, executive, and memory functions. We then consider how variability in cingulate-centered networks could contribute to a range of aging outcomes, including typical aging and unusually successful aging (dubbed "superaging"), as well as early neurodegenerative dementias, including frontotemporal dementia and Alzheimer's disease.
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Affiliation(s)
- Alexandra Touroutoglou
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States
| | - Bradford C Dickerson
- Department of Neurology, Massachusetts General Hospital and Harvard Medical School, Charlestown, MA, United States.
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12
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Ferraro PM, Jester C, Olm CA, Placek K, Agosta F, Elman L, McCluskey L, Irwin DJ, Detre JA, Filippi M, Grossman M, McMillan CT. Perfusion alterations converge with patterns of pathological spread in transactive response DNA-binding protein 43 proteinopathies. Neurobiol Aging 2018; 68:85-92. [PMID: 29751289 DOI: 10.1016/j.neurobiolaging.2018.04.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2018] [Revised: 03/22/2018] [Accepted: 04/11/2018] [Indexed: 11/18/2022]
Abstract
Amyotrophic lateral sclerosis (ALS) and the behavioral variant of frontotemporal dementia (bvFTD) commonly share the presence of transactive response DNA-binding protein 43 (TDP-43) inclusions. Structural magnetic resonance imaging studies demonstrated evidence for TDP-43 pathology spread, but while structural imaging usually reveals overt neuronal loss, perfusion imaging may detect more subtle neural activity alterations. We evaluated perfusion as an early marker for incipient pathology-associated brain alterations in TDP-43 proteinopathies. Cortical thickness (CT) and perfusion measurements were obtained in ALS (N = 18), pathologically and/or genetically confirmed bvFTD-TDP (N = 12), and healthy controls (N = 33). bvFTD showed reduced frontotemporal CT, hypoperfusion encompassing orbitofrontal and temporal cortices, and hyperperfusion in motor and occipital regions. ALS did not show reduced CT, but exhibited hypoperfusion in motor and temporal regions, and hyperperfusion in frontal and occipital cortices. Frontotemporal hypoperfusion and reduced CT correlated with cognitive and behavioral impairments as investigated using Mini-Mental State Examination and Philadelphia Brief Assessment of Cognition in bvFTD, and hypoperfusion in motor regions correlated with motor disability as measured by the ALS Functional Rating Scale-Revised in ALS. Hypoperfusion marked early pathologically involved regions, while hyperperfusion characterized regions of late pathological involvement. Distinct perfusion patterns may provide early markers of pathology distribution in TDP-43 proteinopathies.
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Affiliation(s)
- Pilar M Ferraro
- Department of Neurology, Penn Frontotemporal Degeneration Center, Philadelphia, PA, USA; Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Charles Jester
- Department of Neurology, Penn Frontotemporal Degeneration Center, Philadelphia, PA, USA
| | - Christopher A Olm
- Department of Neurology, Penn Frontotemporal Degeneration Center, Philadelphia, PA, USA; Department of Radiology, Penn Image Computing and Science Laboratory, Philadelphia, PA, USA
| | - Katerina Placek
- Department of Neurology, Penn Frontotemporal Degeneration Center, Philadelphia, PA, USA
| | - Federica Agosta
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Lauren Elman
- Penn Comprehensive ALS Center, University of Pennsylvania, Philadelphia, PA, USA
| | - Leo McCluskey
- Penn Comprehensive ALS Center, University of Pennsylvania, Philadelphia, PA, USA
| | - David J Irwin
- Department of Neurology, Penn Frontotemporal Degeneration Center, Philadelphia, PA, USA
| | - John A Detre
- Department of Neurology, Penn Frontotemporal Degeneration Center, Philadelphia, PA, USA; Department of Radiology, Penn Image Computing and Science Laboratory, Philadelphia, PA, USA
| | - Massimo Filippi
- Neuroimaging Research Unit, Institute of Experimental Neurology, Division of Neuroscience, San Raffaele Scientific Institute, Vita-Salute San Raffaele University, Milan, Italy
| | - Murray Grossman
- Department of Neurology, Penn Frontotemporal Degeneration Center, Philadelphia, PA, USA
| | - Corey T McMillan
- Department of Neurology, Penn Frontotemporal Degeneration Center, Philadelphia, PA, USA.
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Gefen T, Papastefan ST, Rezvanian A, Bigio EH, Weintraub S, Rogalski E, Mesulam MM, Geula C. Von Economo neurons of the anterior cingulate across the lifespan and in Alzheimer's disease. Cortex 2018; 99:69-77. [PMID: 29175073 PMCID: PMC5801202 DOI: 10.1016/j.cortex.2017.10.015] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2017] [Revised: 08/01/2017] [Accepted: 10/18/2017] [Indexed: 11/22/2022]
Abstract
BACKGROUND Throughout the human aging lifespan, neurons acquire an unusually high burden of wear and tear; this is likely why age is considered the strongest risk factor for the development of Alzheimer's Disease (AD). Von Economo neurons (VENs) are rare, spindle-shaped cells mostly populated in anterior cingulate cortex. In a prior study, "SuperAgers" (individuals older than 80 years of age with outstanding memory ability) showed higher VEN densities compared to elderly controls with average memory, and those with amnestic Mild Cognitive Impairment (aMCI). The intrinsic vulnerabilities of these neurons are unclear, and their contribution to neurodegeneration is unknown. The current study investigated the influence of age and the severity of Alzheimer's disease (AD) on VEN density. METHODS VEN and total neuronal densities were quantitated using unbiased stereological methods in the anterior cingulate cortex of postmortem samples from the following subject groups: younger controls (age 20-60), SuperAgers, cognitively average elderly controls (age 65+), individuals diagnosed antemortem with aMCI, and individuals diagnosed antemortem with dementia of AD (N = 5, per group). RESULTS The AD group showed significantly lower VEN density compared to younger and older controls (p < .05), but not compared to the aMCI group, and VENs bearing neurofibrillary tangles were discovered in AD cases. The aMCI group showed lower VEN density than elderly controls, but this was not significant. There was a significant negative correlation between VEN density and Braak stages of AD (p < .001). Consistent with prior findings, SuperAgers showed highest mean VEN density, even when compared to younger cases. CONCLUSIONS VENs in human anterior cingulate cortex are vulnerable to AD pathology, particularly in later stages of pathogenesis. Their densities do not change throughout aging in individuals with average cognition, and they are more numerous in SuperAgers.
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Affiliation(s)
- Tamar Gefen
- Cognitive Neurology and Alzheimer's Disease Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
| | - Steven T Papastefan
- Cognitive Neurology and Alzheimer's Disease Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
| | - Aras Rezvanian
- Cognitive Neurology and Alzheimer's Disease Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
| | - Eileen H Bigio
- Cognitive Neurology and Alzheimer's Disease Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; Department of Pathology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
| | - Sandra Weintraub
- Cognitive Neurology and Alzheimer's Disease Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; Department of Psychiatry and Behavioral Sciences, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
| | - Emily Rogalski
- Cognitive Neurology and Alzheimer's Disease Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
| | - M-Marsel Mesulam
- Cognitive Neurology and Alzheimer's Disease Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; Department of Neurology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
| | - Changiz Geula
- Cognitive Neurology and Alzheimer's Disease Center, Northwestern University Feinberg School of Medicine, Chicago, IL, USA; Department of Cellular and Molecular Biology, Northwestern University Feinberg School of Medicine, Chicago, IL, USA.
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Tan RH, Yang Y, Halliday GM. Multiple neuronal pathologies are common in young patients with pathologically proven Frontotemporal lobar degeneration. Neuropathol Appl Neurobiol 2018; 44:522-532. [DOI: 10.1111/nan.12455] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Revised: 11/20/2017] [Accepted: 12/07/2017] [Indexed: 12/12/2022]
Affiliation(s)
- R H Tan
- Brain and Mind Centre, Sydney Medical School, The University of Sydney, Sydney, Australia.,School of Medical Sciences, University of New South Wales, Sydney, Australia.,Neuroscience Research Australia, Sydney, Australia
| | | | - G M Halliday
- Brain and Mind Centre, Sydney Medical School, The University of Sydney, Sydney, Australia.,School of Medical Sciences, University of New South Wales, Sydney, Australia.,Neuroscience Research Australia, Sydney, Australia
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Tan RH, Yang Y, Kim WS, Dobson-Stone C, Kwok JB, Kiernan MC, Halliday GM. Distinct TDP-43 inclusion morphologies in frontotemporal lobar degeneration with and without amyotrophic lateral sclerosis. Acta Neuropathol Commun 2017; 5:76. [PMID: 29078806 PMCID: PMC5658959 DOI: 10.1186/s40478-017-0480-2] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2017] [Accepted: 10/09/2017] [Indexed: 01/08/2023] Open
Abstract
The identification of the TAR DNA-binding protein 43 (TDP-43) as the ubiquitinated cytoplasmic inclusions in frontotemporal lobar degeneration (FTLD) and amyotrophic lateral sclerosis (ALS) confirmed that these two diseases share similar mechanisms, likely to be linked to the abnormal hyperphosphorylation, ubiquitination and cleavage of pathological TDP-43. Importantly however, a quantitative analysis of TDP-43 inclusions in predilection cortical regions of FTLD, FTLD-ALS and ALS cases has not been undertaken. The present study set out to assess this and demonstrates that distinct TDP-43 inclusion morphologies exist in the anterior cingulate cortex, but not the motor cortex of FTLD and FTLD-ALS. Specifically, in the anterior cingulate cortex of FTLD cases, significant rounded TDP-43 inclusions and rare circumferential TDP-43 inclusions were identified. In contrast, FTLD-ALS cases revealed significant circumferential TDP-43 inclusions and rare rounded TDP-43 inclusions in the anterior cingulate cortex. Distinct TDP-43 inclusion morphologies in the anterior cingulate cortex of FTLD and FTLD-ALS may be linked to heterogeneity in the ubiquitination of pathological TDP-43 inclusions, with the present study providing evidence to suggest the involvement of distinct pathomechanisms in these two overlapping clinical syndromes.
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Early-stage differentiation between presenile Alzheimer's disease and frontotemporal dementia using arterial spin labeling MRI. Eur Radiol 2015; 26:244-53. [PMID: 26024845 PMCID: PMC4666273 DOI: 10.1007/s00330-015-3789-x] [Citation(s) in RCA: 45] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2014] [Revised: 04/01/2015] [Accepted: 04/09/2015] [Indexed: 11/16/2022]
Abstract
Objective To investigate arterial spin labeling (ASL)-MRI for the early diagnosis of and differentiation between the two most common types of presenile dementia: Alzheimer’s disease (AD) and frontotemporal dementia (FTD), and for distinguishing age-related from pathological perfusion changes. Methods Thirteen AD and 19 FTD patients, and 25 age-matched older and 22 younger controls underwent 3D pseudo-continuous ASL-MRI at 3 T. Gray matter (GM) volume and cerebral blood flow (CBF), corrected for partial volume effects, were quantified in the entire supratentorial cortex and in 10 GM regions. Sensitivity, specificity and diagnostic performance were evaluated in regions showing significant CBF differences between patient groups or between patients and older controls. Results AD compared with FTD patients had hypoperfusion in the posterior cingulate cortex, differentiating these with a diagnostic performance of 74 %. Compared to older controls, FTD patients showed hypoperfusion in the anterior cingulate cortex, whereas AD patients showed a more widespread regional hypoperfusion as well as atrophy. Regional atrophy was not different between AD and FTD. Diagnostic performance of ASL to differentiate AD or FTD from controls was good (78-85 %). Older controls showed global hypoperfusion compared to young controls. Conclusion ASL-MRI contributes to early diagnosis of and differentiation between presenile AD and FTD. Key Points • ASL-MRI facilitates differentiation of early Alzheimer’s disease and frontotemporal dementia. • Posterior cingulate perfusion is lower in Alzheimer’s disease than frontotemporal dementia. • Compared to controls, Alzheimer’s disease patients show hypoperfusion in multiple regions. • Compared to controls, frontotemporal dementia patients show focal anterior cingulate hypoperfusion. • Global decreased perfusion in older adults differs from hypoperfusion in dementia.
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Tan RH, Wong S, Kril JJ, Piguet O, Hornberger M, Hodges JR, Halliday GM. Beyond the temporal pole: limbic memory circuit in the semantic variant of primary progressive aphasia. ACTA ACUST UNITED AC 2014; 137:2065-76. [PMID: 24844729 DOI: 10.1093/brain/awu118] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Despite accruing evidence for relative preservation of episodic memory in the semantic variant of primary progressive aphasia (previously semantic dementia), the neural basis for this remains unclear, particularly in light of their well-established hippocampal involvement. We recently investigated the Papez network of memory structures across pathological subtypes of behavioural variant frontotemporal dementia and demonstrated severe degeneration of all relay nodes, with the anterior thalamus in particular emerging as crucial for intact episodic memory. The present study investigated the status of key components of Papez circuit (hippocampus, mammillary bodies, anterior thalamus, cingulate cortex) and anterior temporal cortex using volumetric and quantitative cell counting methods in pathologically-confirmed cases with semantic variant of primary progressive aphasia (n = 8; 61-83 years; three males), behavioural variant frontotemporal dementia with TDP pathology (n = 9; 53-82 years; six males) and healthy controls (n = 8, 50-86 years; four males). Behavioural variant frontotemporal dementia cases with TDP pathology were selected because of the association between the semantic variant of primary progressive aphasia and TDP pathology. Our findings revealed that the semantic variant of primary progressive aphasia and behavioural variant frontotemporal dementia show similar degrees of anterior thalamic atrophy. The mammillary bodies and hippocampal body and tail were preserved in the semantic variant of primary progressive aphasia but were significantly atrophic in behavioural variant frontotemporal dementia. Importantly, atrophy in the anterior thalamus and mild progressive atrophy in the body of the hippocampus emerged as the main memory circuit regions correlated with increasing dementia severity in the semantic variant of primary progressive aphasia. Quantitation of neuronal populations in the cingulate cortices confirmed the selective loss of anterior cingulate von Economo neurons in behavioural variant frontotemporal dementia. We also show that by end-stage these neurons selectively degenerate in the semantic variant of primary progressive aphasia with preservation of neurons in the posterior cingulate cortex. Overall, our findings demonstrate for the first time, severe atrophy, although not necessarily neuronal loss, across all relay nodes of Papez circuit with the exception of the mammillary bodies and hippocampal body and tail in the semantic variant of primary progressive aphasia. Despite the longer disease course in the semantic variant of primary progressive aphasia compared with behavioural variant frontotemporal dementia, we suggest here that the neural preservation of crucial memory relays (hippocampal→mammillary bodies and posterior cingulate→hippocampus) likely reflects the conservation of specific episodic memory components observed in most patients with semantic variant of primary progressive aphasia.
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Affiliation(s)
- Rachel H Tan
- 1 Neuroscience Research Australia, Barker Street, Randwick, Sydney, 2031, Australia2 School of Medical Sciences, University of New South Wales, Sydney, 2031, Australia
| | - Stephanie Wong
- 1 Neuroscience Research Australia, Barker Street, Randwick, Sydney, 2031, Australia
| | - Jillian J Kril
- 3 Disciplines of Pathology and Medicine, Sydney Medical School, The University of Sydney, Sydney, 2006, Australia
| | - Olivier Piguet
- 1 Neuroscience Research Australia, Barker Street, Randwick, Sydney, 2031, Australia2 School of Medical Sciences, University of New South Wales, Sydney, 2031, Australia4 ARC Centre of Excellence in Cognition and its Disorders, Sydney, 2109, Australia
| | - Michael Hornberger
- 1 Neuroscience Research Australia, Barker Street, Randwick, Sydney, 2031, Australia2 School of Medical Sciences, University of New South Wales, Sydney, 2031, Australia4 ARC Centre of Excellence in Cognition and its Disorders, Sydney, 2109, Australia
| | - John R Hodges
- 1 Neuroscience Research Australia, Barker Street, Randwick, Sydney, 2031, Australia2 School of Medical Sciences, University of New South Wales, Sydney, 2031, Australia4 ARC Centre of Excellence in Cognition and its Disorders, Sydney, 2109, Australia
| | - Glenda M Halliday
- 1 Neuroscience Research Australia, Barker Street, Randwick, Sydney, 2031, Australia2 School of Medical Sciences, University of New South Wales, Sydney, 2031, Australia
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