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Ohm DT, Rhodes E, Bahena A, Capp N, Lowe M, Sabatini P, Trotman W, Olm CA, Phillips J, Prabhakaran K, Rascovsky K, Massimo L, McMillan C, Gee J, Tisdall MD, Yushkevich PA, Lee EB, Grossman M, Irwin DJ. Neuroanatomical and cellular degeneration associated with a social disorder characterized by new ritualistic belief systems in a TDP-C patient vs. a Pick patient. Front Neurol 2023; 14:1245886. [PMID: 37900607 PMCID: PMC10600461 DOI: 10.3389/fneur.2023.1245886] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2023] [Accepted: 08/15/2023] [Indexed: 10/31/2023] Open
Abstract
Frontotemporal dementia (FTD) is a spectrum of clinically and pathologically heterogenous neurodegenerative dementias. Clinical and anatomical variants of FTD have been described and associated with underlying frontotemporal lobar degeneration (FTLD) pathology, including tauopathies (FTLD-tau) or TDP-43 proteinopathies (FTLD-TDP). FTD patients with predominant degeneration of anterior temporal cortices often develop a language disorder of semantic knowledge loss and/or a social disorder often characterized by compulsive rituals and belief systems corresponding to predominant left or right hemisphere involvement, respectively. The neural substrates of these complex social disorders remain unclear. Here, we present a comparative imaging and postmortem study of two patients, one with FTLD-TDP (subtype C) and one with FTLD-tau (subtype Pick disease), who both developed new rigid belief systems. The FTLD-TDP patient developed a complex set of values centered on positivity and associated with specific physical and behavioral features of pigs, while the FTLD-tau patient developed compulsive, goal-directed behaviors related to general themes of positivity and spirituality. Neuroimaging showed left-predominant temporal atrophy in the FTLD-TDP patient and right-predominant frontotemporal atrophy in the FTLD-tau patient. Consistent with antemortem cortical atrophy, histopathologic examinations revealed severe loss of neurons and myelin predominantly in the anterior temporal lobes of both patients, but the FTLD-tau patient showed more bilateral, dorsolateral involvement featuring greater pathology and loss of projection neurons and deep white matter. These findings highlight that the regions within and connected to anterior temporal lobes may have differential vulnerability to distinct FTLD proteinopathies and serve important roles in human belief systems.
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Affiliation(s)
- Daniel T. Ohm
- Penn Digital Neuropathology Laboratory, Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - Emma Rhodes
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - Alejandra Bahena
- Penn Digital Neuropathology Laboratory, Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - Noah Capp
- Penn Digital Neuropathology Laboratory, Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - MaKayla Lowe
- Penn Digital Neuropathology Laboratory, Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - Philip Sabatini
- Penn Digital Neuropathology Laboratory, Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - Winifred Trotman
- Penn Digital Neuropathology Laboratory, Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - Christopher A. Olm
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - Jeffrey Phillips
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - Karthik Prabhakaran
- Penn Image Computing and Science Lab, Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States
| | - Katya Rascovsky
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - Lauren Massimo
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - Corey McMillan
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - James Gee
- Penn Image Computing and Science Lab, Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States
| | - M. Dylan Tisdall
- Center for Advanced Magnetic Resonance Imaging and Spectroscopy, Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States
| | - Paul A. Yushkevich
- Penn Image Computing and Science Lab, Department of Radiology, University of Pennsylvania, Philadelphia, PA, United States
| | - Edward B. Lee
- Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA, United States
| | - Murray Grossman
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
| | - David J. Irwin
- Penn Digital Neuropathology Laboratory, Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA, United States
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Coppen EM, Jacobs M, van der Zwaan KF, Middelkoop HAM, Roos RAC. Visual Object Perception in Premanifest and Early Manifest Huntington's Disease. Arch Clin Neuropsychol 2020; 34:1320-1328. [PMID: 30796801 PMCID: PMC7227804 DOI: 10.1093/arclin/acz002] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 12/31/2018] [Accepted: 01/11/2019] [Indexed: 01/06/2023] Open
Abstract
OBJECTIVE In Huntington's disease (HD), a hereditary neurodegenerative disorder, cognitive impairment in early disease stages mainly involves executive dysfunction. However, visual cognitive deficits have additionally been reported and are of clinical relevance given their influence on daily life and overall cognitive performance. This study aimed to assess visual perceptual skills in HD gene carriers. METHODS Subtasks of the Visual Object and Space Perception battery and Groningen Intelligence Test were administered in 62 participants (18 healthy controls, 22 participants with a genetic confirmation of HD without symptoms, i.e., premanifest HD, and 22 participants with a genetic confirmation of HD with symptoms, i.e., manifest HD). Group differences in task performance were measured using analysis of covariance with and without correction for age. Receiver Operating Characteristics (ROC) analysis was performed to examine which task best discriminated between groups and cut-off scores were provided. RESULTS Manifest HD performed significantly worse compared to both controls and premanifest HD on all visual perceptional tasks. Premanifest HD did not differ in task performance from controls. Besides the Shape Detection, all tasks were robust in discriminating between groups. The Animal Silhouettes test was most accurate in discriminating manifest HD from premanifest HD (AUC = 0.90, SE = 0.048, p < .001). CONCLUSION Visual perceptual deficits are present in early manifest HD, especially an impaired recognition of animals and objects from sketched silhouettes, and not in premanifest HD. This suggests that decline in visual processing only occurs in clinical disease stages. The visual cognitive battery, especially the Silhouettes tasks used in this study is sensitive in discriminating manifest HD from premanifest HD and controls.
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Affiliation(s)
- Emma M Coppen
- Department of Neurology, Leiden University Medical Center, 2333 ZA, Leiden, the Netherlands
| | - Milou Jacobs
- Department of Neurology, Leiden University Medical Center, 2333 ZA, Leiden, the Netherlands
| | - Kasper F van der Zwaan
- Department of Neurology, Leiden University Medical Center, 2333 ZA, Leiden, the Netherlands
| | - Huub A M Middelkoop
- Department of Clinical Neuropsychology, Leiden University Medical Center, 2333 ZA, Leiden, the Netherlands.,Department of Psychology, Leiden University, 2300 RB, Leiden, the Netherlands
| | - Raymund A C Roos
- Department of Neurology, Leiden University Medical Center, 2333 ZA, Leiden, the Netherlands
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Abstract
PURPOSE OF REVIEW This article summarizes the clinical and anatomic features of the three named variants of primary progressive aphasia (PPA): semantic variant PPA, nonfluent/agrammatic variant PPA, and logopenic variant PPA. Three stroke aphasia syndromes that resemble the PPA variants (Broca aphasia, Wernicke aphasia, and conduction aphasia) are also presented. RECENT FINDINGS Semantic variant PPA and Wernicke aphasia are characterized by fluent speech with naming and comprehension difficulty; these syndromes are associated with disease in different portions of the left temporal lobe. Patients with nonfluent/agrammatic variant PPA or Broca aphasia have nonfluent speech with grammatical difficulty; these syndromes are associated with disease centered in the left inferior frontal lobe. Patients with logopenic variant PPA or conduction aphasia have difficulty with repetition and word finding in conversational speech; these syndromes are associated with disease in the left inferior parietal lobe. While PPA and stroke aphasias resemble one another, this article also presents their distinguishing features. SUMMARY Primary progressive and stroke aphasia syndromes interrupt the left perisylvian language network, resulting in identifiable aphasic syndromes.
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Borghi AM, Barca L, Binkofski F, Castelfranchi C, Pezzulo G, Tummolini L. Words as social tools: Language, sociality and inner grounding in abstract concepts. Phys Life Rev 2019; 29:120-153. [DOI: 10.1016/j.plrev.2018.12.001] [Citation(s) in RCA: 73] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2018] [Revised: 12/05/2018] [Accepted: 12/05/2018] [Indexed: 11/24/2022]
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Abstract
Primary progressive aphasia (PPA) refers to a disorder of declining language associated with neurodegenerative diseases such as frontotemporal degeneration and Alzheimer disease. Variants of PPA are important to recognize from a medical perspective because these syndromes are clinical markers suggesting specific underlying pathology. In this review, I discuss linguistic aspects of PPA syndromes that may prove informative for parsing our language mechanism and identifying the neural representation of fundamental elements of language. I focus on the representation of word meaning in a discussion of semantic variant PPA, grammatical comprehension and expression in a discussion of nonfluent/agrammatic variant PPA, the supporting role of short-term memory in a discussion of logopenic variant PPA, and components of language associated with discourse in a discussion of behavioral variant frontotemporal dementia. PPA provides a novel perspective that uniquely addresses facets of language and its disorders while complementing traditional aphasia syndromes that follow stroke.
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Affiliation(s)
- Murray Grossman
- Penn Frontotemporal Degeneration Center and Department of Neurology, University of Pennsylvania, Philadelphia, Pennsylvania 19104
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Task-Related Dynamic Division of Labor Between Anterior Temporal and Lateral Occipital Cortices in Representing Object Size. J Neurosci 2017; 36:4662-8. [PMID: 27122025 DOI: 10.1523/jneurosci.2829-15.2016] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Accepted: 01/25/2016] [Indexed: 11/21/2022] Open
Abstract
UNLABELLED Object size is represented by functionally distinct sectors along the ventral visual pathway. The early visual cortex encodes objects' sensory-retinal size. Subsequently, the occipitotemporal cortex computes objects' canonical size based on statistical regularities of visual features. Although the neurocomputation of size has been studied in a "bottom-up" sensory-driven framework, little is known about how perceptual size information is transformed into conceptual knowledge and how this computation is modulated by "top-down" goal-driven signals. Using continuous theta burst stimulation, we demonstrated that behavioral goal shapes the neurocognitive network underpinning object size. We manipulated the congruency of perceptual versus conceptual object size, which provides a robust behavioral probe reflecting implicit size knowledge. Neurostimulation was targeted at the lateral occipital cortex (LOC), a key region for object perception, or the anterior temporal lobe (ATL), a "hub" of supramodal conceptual processing. We observed striking contextual modulation of the neurocognitive architecture: when human participants judged perceptual size, the congruency effect was significantly attenuated by LOC stimulation but stayed resilient to ATL stimulation. By contrast, when they judged conceptual size, both LOC and ATL stimulation eradicated the otherwise robust effect. Our findings demonstrate disparate functional profiles of the LOC and ATL, providing the first evidence of a malleable network adaptively altering its division of labor with top-down states. The LOC, regardless of task demand, automatically represents "bottom-up" statistical regularities of visual conformation (reflecting typical object size), whereas the ATL contributes to this computation when the context requires semantically based linkage of visual attributes to object recognition. SIGNIFICANCE STATEMENT In the present study, we provide compelling evidence that the "top-down" cognitive state of an observer changes the dynamic interaction between different subregions of the ventral temporal cortex. Using inhibitory neurostimulation combined with a novel paradigm, we demonstrate a flexible division of labor in the neurocognitive architecture that underpins size knowledge: the lateral occipital cortex codes perceptually based aspects (statistical visual configuration of small/large objects), whereas the anterior temporal lobe represents semantically based aspects (object identity), with their involvement interactively weighted by task demand. The interactive nature of the ventral temporal cortex highlights how top-down modulation constrains and shapes neural representations in the visual system.
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McMillan CT, Boyd C, Gross RG, Weinstein J, Firn K, Toledo JB, Rascovsky K, Shaw L, Wolk DA, Irwin DJ, Lee EB, Trojanowski JQ, Grossman M. Multimodal imaging evidence of pathology-mediated disease distribution in corticobasal syndrome. Neurology 2016; 87:1227-34. [PMID: 27543644 DOI: 10.1212/wnl.0000000000003119] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2015] [Accepted: 06/07/2016] [Indexed: 01/26/2023] Open
Abstract
OBJECTIVE To use multimodal neuroimaging to evaluate the influence of heterogeneous underlying pathology in corticobasal syndrome (CBS) on the neuroanatomical distribution of disease. METHODS We performed a retrospective evaluation of 35 patients with CBS with T1-weighted MRI, diffusion tensor imaging, and neuropathologic, genetic, or CSF evidence of underlying pathology. Patients were assigned to 2 groups: those with evidence of Alzheimer pathology (CBS-AD) and those without Alzheimer pathology (CBS-non-AD). Group comparisons of CBS-AD and CBS-non-AD assessed clinical features, gray matter (GM) cortical thickness, and white matter (WM) fractional anisotropy. RESULTS CBS-AD was found in 34% (n = 12) and CBS-non-AD in 66% (n = 23) of CBS patients. Clinical evaluations revealed that CBS-non-AD had a higher frequency of asymmetric rigidity compared to CBS-AD, but groups otherwise did not differ in dementia severity, impairments in cognition, or rates of extrapyramidal symptoms. We found frontoparietal GM and WM disease in each group compared to healthy, demographically comparable controls, as well as multimodal neuroimaging evidence of a double dissociation: CBS-non-AD had WM disease in the corpus callosum, corticospinal tract, and superior longitudinal fasciculus relative to CBS-AD, and CBS-AD had reduced temporoparietal GM relative to CBS-non-AD, including the precuneus and posterior cingulate. CONCLUSIONS Patients with CBS have a pathology-mediated dissociation of GM and WM disease. Multimodality neuroimaging may be useful for improving in vivo pathologic diagnosis of CBS.
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Affiliation(s)
- Corey T McMillan
- From the Department of Neurology (C.T.M., C.B., R.G.G., J.W., K.F., K.R., D.A.W., D.J.I., M.G.) and Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine (J.B.T., L.S., D.J.I., E.B.L., J.Q.T.), Perelman School of Medicine, University of Pennsylvania, Philadelphia.
| | - Clara Boyd
- From the Department of Neurology (C.T.M., C.B., R.G.G., J.W., K.F., K.R., D.A.W., D.J.I., M.G.) and Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine (J.B.T., L.S., D.J.I., E.B.L., J.Q.T.), Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Rachel G Gross
- From the Department of Neurology (C.T.M., C.B., R.G.G., J.W., K.F., K.R., D.A.W., D.J.I., M.G.) and Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine (J.B.T., L.S., D.J.I., E.B.L., J.Q.T.), Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Jessica Weinstein
- From the Department of Neurology (C.T.M., C.B., R.G.G., J.W., K.F., K.R., D.A.W., D.J.I., M.G.) and Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine (J.B.T., L.S., D.J.I., E.B.L., J.Q.T.), Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Kim Firn
- From the Department of Neurology (C.T.M., C.B., R.G.G., J.W., K.F., K.R., D.A.W., D.J.I., M.G.) and Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine (J.B.T., L.S., D.J.I., E.B.L., J.Q.T.), Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Jon B Toledo
- From the Department of Neurology (C.T.M., C.B., R.G.G., J.W., K.F., K.R., D.A.W., D.J.I., M.G.) and Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine (J.B.T., L.S., D.J.I., E.B.L., J.Q.T.), Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Katya Rascovsky
- From the Department of Neurology (C.T.M., C.B., R.G.G., J.W., K.F., K.R., D.A.W., D.J.I., M.G.) and Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine (J.B.T., L.S., D.J.I., E.B.L., J.Q.T.), Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Leslie Shaw
- From the Department of Neurology (C.T.M., C.B., R.G.G., J.W., K.F., K.R., D.A.W., D.J.I., M.G.) and Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine (J.B.T., L.S., D.J.I., E.B.L., J.Q.T.), Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - David A Wolk
- From the Department of Neurology (C.T.M., C.B., R.G.G., J.W., K.F., K.R., D.A.W., D.J.I., M.G.) and Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine (J.B.T., L.S., D.J.I., E.B.L., J.Q.T.), Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - David J Irwin
- From the Department of Neurology (C.T.M., C.B., R.G.G., J.W., K.F., K.R., D.A.W., D.J.I., M.G.) and Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine (J.B.T., L.S., D.J.I., E.B.L., J.Q.T.), Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Edward B Lee
- From the Department of Neurology (C.T.M., C.B., R.G.G., J.W., K.F., K.R., D.A.W., D.J.I., M.G.) and Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine (J.B.T., L.S., D.J.I., E.B.L., J.Q.T.), Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - John Q Trojanowski
- From the Department of Neurology (C.T.M., C.B., R.G.G., J.W., K.F., K.R., D.A.W., D.J.I., M.G.) and Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine (J.B.T., L.S., D.J.I., E.B.L., J.Q.T.), Perelman School of Medicine, University of Pennsylvania, Philadelphia
| | - Murray Grossman
- From the Department of Neurology (C.T.M., C.B., R.G.G., J.W., K.F., K.R., D.A.W., D.J.I., M.G.) and Center for Neurodegenerative Disease Research, Department of Pathology and Laboratory Medicine (J.B.T., L.S., D.J.I., E.B.L., J.Q.T.), Perelman School of Medicine, University of Pennsylvania, Philadelphia
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Olm CA, Kandel BM, Avants BB, Detre JA, Gee JC, Grossman M, McMillan CT. Arterial spin labeling perfusion predicts longitudinal decline in semantic variant primary progressive aphasia. J Neurol 2016; 263:1927-38. [PMID: 27379517 DOI: 10.1007/s00415-016-8221-1] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2015] [Revised: 04/22/2016] [Accepted: 06/26/2016] [Indexed: 01/04/2023]
Abstract
The objective of the study was to evaluate the prognostic value of regional cerebral blood flow (CBF) measured by arterial spin labeled (ASL) perfusion MRI in patients with semantic variant primary progressive aphasia (svPPA). We acquired pseudo-continuous ASL (pCASL) MRI and whole-brain T1-weighted structural MRI in svPPA patients (N = 13) with cerebrospinal fluid biomarkers consistent with frontotemporal lobar degeneration pathology. Follow-up T1-weighted MRI was available in a subset of patients (N = 8). We performed whole-brain comparisons of partial volume-corrected CBF and cortical thickness between svPPA and controls, and compared baseline and follow-up cortical thickness in regions of significant hypoperfusion and hyperperfusion. Patients with svPPA showed partial volume-corrected hypoperfusion relative to controls in left temporal lobe and insula. svPPA patients also had typical cortical thinning in anterior temporal, insula, and inferior frontal regions at baseline. Volume-corrected hypoperfusion was seen in areas of significant cortical thinning such as the left temporal lobe and insula. Additional regions of hypoperfusion corresponded to areas without cortical thinning. We also observed regions of hyperperfusion, some associated with cortical thinning and others without cortical thinning, including right superior temporal, inferior parietal, and orbitofrontal cortices. Regions of hypoperfusion and hyperperfusion near cortical thinning at baseline had significant longitudinal thinning between baseline and follow-up scans, but perfusion changes in distant areas did not show progressive thinning. Our findings suggest ASL MRI may be sensitive to functional changes not readily apparent in structural MRI, and specific changes in perfusion may be prognostic markers of disease progression in a manner consistent with cell-to-cell spreading pathology.
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Affiliation(s)
- Christopher A Olm
- Department of Neurology, Penn Frontotemporal Degeneration Center, University of Pennsylvania Perelman School of Medicine, 3 West Gates, Philadelphia, PA, 19104, USA
| | - Benjamin M Kandel
- Department of Radiology, Penn Image Computing and Science Lab, Philadelphia, PA, 19104, USA
| | - Brian B Avants
- Department of Radiology, Penn Image Computing and Science Lab, Philadelphia, PA, 19104, USA
| | - John A Detre
- Departments of Neurology and Radiology, University of Pennsylvania, Philadelphia, PA, 19104, USA
| | - James C Gee
- Department of Radiology, Penn Image Computing and Science Lab, Philadelphia, PA, 19104, USA
| | - Murray Grossman
- Department of Neurology, Penn Frontotemporal Degeneration Center, University of Pennsylvania Perelman School of Medicine, 3 West Gates, Philadelphia, PA, 19104, USA
| | - Corey T McMillan
- Department of Neurology, Penn Frontotemporal Degeneration Center, University of Pennsylvania Perelman School of Medicine, 3 West Gates, Philadelphia, PA, 19104, USA.
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Ash S, Ternes K, Bisbing T, Min NE, Moran E, York C, McMillan CT, Irwin DJ, Grossman M. Dissociation of quantifiers and object nouns in speech in focal neurodegenerative disease. Neuropsychologia 2016; 89:141-152. [PMID: 27301638 DOI: 10.1016/j.neuropsychologia.2016.06.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2015] [Revised: 06/10/2016] [Accepted: 06/10/2016] [Indexed: 10/21/2022]
Abstract
Quantifiers such as many and some are thought to depend in part on the conceptual representation of number knowledge, while object nouns such as cookie and boy appear to depend in part on visual feature knowledge associated with object concepts. Further, number knowledge is associated with a frontal-parietal network while object knowledge is related in part to anterior and ventral portions of the temporal lobe. We examined the cognitive and anatomic basis for the spontaneous speech production of quantifiers and object nouns in non-aphasic patients with focal neurodegenerative disease associated with corticobasal syndrome (CBS, n=33), behavioral variant frontotemporal degeneration (bvFTD, n=54), and semantic variant primary progressive aphasia (svPPA, n=19). We recorded a semi-structured speech sample elicited from patients and healthy seniors (n=27) during description of the Cookie Theft scene. We observed a dissociation: CBS and bvFTD were significantly impaired in the production of quantifiers but not object nouns, while svPPA were significantly impaired in the production of object nouns but not quantifiers. MRI analysis revealed that quantifier production deficits in CBS and bvFTD were associated with disease in a frontal-parietal network important for number knowledge, while impaired production of object nouns in all patient groups was related to disease in inferior temporal regions important for representations of visual feature knowledge of objects. These findings imply that partially dissociable representations in semantic memory may underlie different segments of the lexicon.
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Affiliation(s)
- Sharon Ash
- Department of Neurology and the Penn Frontotemporal Degeneration Center, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA, United States.
| | - Kylie Ternes
- Department of Neurology and the Penn Frontotemporal Degeneration Center, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA, United States.
| | - Teagan Bisbing
- Department of Neurology and the Penn Frontotemporal Degeneration Center, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA, United States.
| | - Nam Eun Min
- Department of Neurology and the Penn Frontotemporal Degeneration Center, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA, United States.
| | - Eileen Moran
- Department of Neurology and the Penn Frontotemporal Degeneration Center, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA, United States.
| | - Collin York
- Department of Neurology and the Penn Frontotemporal Degeneration Center, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA, United States.
| | - Corey T McMillan
- Department of Neurology and the Penn Frontotemporal Degeneration Center, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA, United States.
| | - David J Irwin
- Department of Neurology and the Penn Frontotemporal Degeneration Center, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA, United States; Center for Neurodegenerative Disease Research, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA, United States.
| | - Murray Grossman
- Department of Neurology and the Penn Frontotemporal Degeneration Center, Perelman School of Medicine of the University of Pennsylvania, Philadelphia, PA, United States.
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Bisbing TA, Olm CA, McMillan CT, Rascovsky K, Baehr L, Ternes K, Irwin DJ, Clark R, Grossman M. Estimating frontal and parietal involvement in cognitive estimation: a study of focal neurodegenerative diseases. Front Hum Neurosci 2015; 9:317. [PMID: 26089786 PMCID: PMC4454843 DOI: 10.3389/fnhum.2015.00317] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 05/18/2015] [Indexed: 12/14/2022] Open
Abstract
We often estimate an unknown value based on available relevant information, a process known as cognitive estimation. In this study, we assess the cognitive and neuroanatomic basis for quantitative estimation by examining deficits in patients with focal neurodegenerative disease in frontal and parietal cortex. Executive function and number knowledge are key components in cognitive estimation. Prefrontal cortex has been implicated in multilevel reasoning and planning processes, and parietal cortex has been associated with number knowledge required for such estimations. We administered the Biber cognitive estimation test (BCET) to assess cognitive estimation in 22 patients with prefrontal disease due to behavioral variant frontotemporal dementia (bvFTD), to 17 patients with parietal disease due to corticobasal syndrome (CBS) or posterior cortical atrophy (PCA) and 11 patients with mild cognitive impairment (MCI). Both bvFTD and CBS/PCA patients had significantly more difficulty with cognitive estimation than controls. MCI were not impaired on BCET relative to controls. Regression analyses related BCET performance to gray matter atrophy in right lateral prefrontal and orbital frontal cortices in bvFTD, and to atrophy in right inferior parietal cortex, right insula, and fusiform cortices in CBS/PCA. These results are consistent with the hypothesis that a frontal-parietal network plays a crucial role in cognitive estimation.
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Affiliation(s)
- Teagan A Bisbing
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA USA
| | - Christopher A Olm
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA USA
| | - Corey T McMillan
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA USA
| | - Katya Rascovsky
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA USA
| | - Laura Baehr
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA USA
| | - Kylie Ternes
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA USA
| | - David J Irwin
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA USA
| | - Robin Clark
- Department of Linguistics, University of Pennsylvania, Philadelphia, PA USA
| | - Murray Grossman
- Penn Frontotemporal Degeneration Center, Department of Neurology, University of Pennsylvania, Philadelphia, PA USA
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11
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Spotorno N, McMillan CT, Powers JP, Clark R, Grossman M. Counting or chunking? Mathematical and heuristic abilities in patients with corticobasal syndrome and posterior cortical atrophy. Neuropsychologia 2014; 64:176-83. [PMID: 25278132 DOI: 10.1016/j.neuropsychologia.2014.09.030] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2014] [Revised: 09/15/2014] [Accepted: 09/17/2014] [Indexed: 01/29/2023]
Abstract
A growing amount of empirical data is showing that the ability to manipulate quantities in a precise and efficient fashion is rooted in cognitive mechanisms devoted to specific aspects of numbers processing. The analog number system (ANS) has a reasonable representation of quantities up to about 4, and represents larger quantities on the basis of a numerical ratio between quantities. In order to represent the precise cardinality of a number, the ANS may be supported by external algorithms such as language, leading to a "precise number system". In the setting of limited language, other number-related systems can appear. For example the parallel individuation system (PIS) supports a "chunking mechanism" that clusters units of larger numerosities into smaller subsets. In the present study we investigated number processing in non-aphasic patients with corticobasal syndrome (CBS) and posterior cortical atrophy (PCA), two neurodegenerative conditions that are associated with progressive parietal atrophy. The present study investigated these number systems in CBS and PCA by assessing the property of the ANS associated with smaller and larger numerosities, and the chunking property of the PIS. The results revealed that CBS/PCA patients are impaired in simple calculations (e.g., addition and subtraction) and that their performance strongly correlates with the size of the numbers involved in these calculations, revealing a clear magnitude effect. This magnitude effect was correlated with gray matter atrophy in parietal regions. Moreover, a numeral-dots transcoding task showed that CBS/PCA patients were able to take advantage of clustering in the spatial distribution of the dots of the array. The relative advantage associated with chunking compared to a random spatial distribution correlated with both parietal and prefrontal regions. These results shed light on the properties of systems for representing number knowledge in non-aphasic patients with CBS and PCA.
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Affiliation(s)
- Nicola Spotorno
- University of Pennsylvania, Perelman School of Medicine, Penn Frontotemporal Degeneration Center, Philadelphia, PA 19104, USA.
| | - Corey T McMillan
- University of Pennsylvania, Perelman School of Medicine, Penn Frontotemporal Degeneration Center, Philadelphia, PA 19104, USA
| | - John P Powers
- University of Pennsylvania, Perelman School of Medicine, Penn Frontotemporal Degeneration Center, Philadelphia, PA 19104, USA
| | - Robin Clark
- University of Pennsylvania, Department of Linguistics, Philadelphia, PA 19104, USA
| | - Murray Grossman
- University of Pennsylvania, Perelman School of Medicine, Penn Frontotemporal Degeneration Center, Philadelphia, PA 19104, USA
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12
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Olm CA, McMillan CT, Spotorno N, Clark R, Grossman M. The relative contributions of frontal and parietal cortex for generalized quantifier comprehension. Front Hum Neurosci 2014; 8:610. [PMID: 25147520 PMCID: PMC4124462 DOI: 10.3389/fnhum.2014.00610] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 07/21/2014] [Indexed: 12/13/2022] Open
Abstract
Quantifiers, like “some” or “few,” are frequent in daily language. Linguists posit at least three distinct classes of quantifiers: cardinal quantifiers that rely on numerosity, majority quantifiers that additionally depend on executive resources, and logical quantifiers that rely on perceptual attention. We used BOLD fMRI to investigate the roles of frontal and parietal regions in quantifier comprehension. Participants performed a sentence-picture verification task to determine whether a sentence containing a quantifier accurately describes a picture. A whole-brain analysis identified a network involved in quantifier comprehension: This implicated bilateral inferior parietal, superior parietal and dorsolateral prefrontal cortices, and right inferior frontal cortex. We then performed region-of-interest analyses to assess the relative contribution of each region for each quantifier class. Inferior parietal cortex was equally activated across all quantifier classes, consistent with prior studies implicating the region for quantifier comprehension due in part to its role in the representation of number knowledge. Right superior parietal cortex was up-regulated in comparison to frontal regions for cardinal and logical quantifiers, but parietal and frontal regions were equally activated for majority quantifiers and each frontal region is most highly activated for majority quantifiers. This finding is consistent with the hypothesis that majority quantifiers rely on numerosity mechanisms in parietal cortex and executive mechanisms in frontal cortex. Also, right inferior frontal cortex was up-regulated for logical compared to cardinal quantifiers, which may be related to selection demands associated with logical quantifier comprehension. We conclude that distinct components of a large-scale fronto-parietal network contribute to specific aspects of quantifier comprehension, and that this biologically defined network is consistent with cognitive theories of quantifier meaning.
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Affiliation(s)
- Christopher A Olm
- Penn Frontotemporal Degeneration Center, Department of Neurology, Perelman School of Medicine, University of Pennsylvania Philadelphia, PA, USA
| | - Corey T McMillan
- Penn Frontotemporal Degeneration Center, Department of Neurology, Perelman School of Medicine, University of Pennsylvania Philadelphia, PA, USA
| | - Nicola Spotorno
- Penn Frontotemporal Degeneration Center, Department of Neurology, Perelman School of Medicine, University of Pennsylvania Philadelphia, PA, USA
| | - Robin Clark
- Department of Linguistics, University of Pennsylvania Philadelphia, PA, USA
| | - Murray Grossman
- Penn Frontotemporal Degeneration Center, Department of Neurology, Perelman School of Medicine, University of Pennsylvania Philadelphia, PA, USA
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13
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Kertesz A, Harciarek M. Primary progressive aphasia. Scand J Psychol 2014; 55:191-201. [DOI: 10.1111/sjop.12105] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2013] [Accepted: 01/05/2014] [Indexed: 12/12/2022]
Affiliation(s)
- Andrew Kertesz
- Department of Clinical Neurological Sciences; Western University; London Ontario Canada
| | - Michał Harciarek
- Division of Clinical Psychology and Neuropsychology; Institute of Psychology; University of Gdańsk; Gdańsk Poland
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14
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Rascovsky K, Grossman M. Clinical diagnostic criteria and classification controversies in frontotemporal lobar degeneration. Int Rev Psychiatry 2013; 25:145-58. [PMID: 23611345 PMCID: PMC3906583 DOI: 10.3109/09540261.2013.763341] [Citation(s) in RCA: 59] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Frontotemporal lobar degeneration (FTLD) can manifest as a spectrum of clinical syndromes, ranging from behavioural impairment to language or motor dysfunction. Recently, revised diagnostic criteria have been proposed for the behavioural and progressive aphasia syndromes associated with frontotemporal degeneration. The present review will summarize these diagnostic guidelines and highlight some lingering controversies in the classification of FTLD clinical syndromes. We will discuss common tools and methods used to identify the insidious changes of behavioural variant frontotemporal dementia (bvFTD), the value of new, patient-based tasks of orbitofrontal function, and the issue of a benign or 'phenocopy' variant of bvFTD. With regard to primary progressive aphasia (PPA), we will discuss the scope of the semantic disorder in semantic-variant PPA, the nature of the speech disorder in non-fluent, agrammatic PPA, and the preliminary utility of a logopenic PPA classification.
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Affiliation(s)
- Katya Rascovsky
- Department of Neurology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA.
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15
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Pariyadath V, Plitt MH, Churchill SJ, Eagleman DM. Why overlearned sequences are special: distinct neural networks for ordinal sequences. Front Hum Neurosci 2012; 6:328. [PMID: 23267320 PMCID: PMC3526771 DOI: 10.3389/fnhum.2012.00328] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2012] [Accepted: 11/25/2012] [Indexed: 11/13/2022] Open
Abstract
Several observations suggest that overlearned ordinal categories (e.g., letters, numbers, weekdays, months) are processed differently than non-ordinal categories in the brain. In synesthesia, for example, anomalous perceptual experiences are most often triggered by members of ordinal categories (Rich et al., 2005; Eagleman, 2009). In semantic dementia (SD), the processing of ordinal stimuli appears to be preserved relative to non-ordinal ones (Cappelletti et al., 2001). Moreover, ordinal stimuli often map onto unconscious spatial representations, as observed in the SNARC effect (Dehaene et al., 1993; Fias, 1996). At present, little is known about the neural representation of ordinal categories. Using functional neuroimaging, we show that words in ordinal categories are processed in a fronto-temporo-parietal network biased toward the right hemisphere. This differs from words in non-ordinal categories (such as names of furniture, animals, cars, and fruit), which show an expected bias toward the left hemisphere. Further, we find that increased predictability of stimulus order correlates with smaller regions of BOLD activation, a phenomenon we term prediction suppression. Our results provide new insights into the processing of ordinal stimuli, and suggest a new anatomical framework for understanding the patterns seen in synesthesia, unconscious spatial representation, and SD.
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Affiliation(s)
- Vani Pariyadath
- Department of Neuroscience, Baylor College of Medicine Houston, TX, USA
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16
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Koenig P, Smith EE, Grossman M. Semantic categorisation of novel objects in frontotemporal dementia. Cogn Neuropsychol 2012; 23:541-62. [PMID: 21049343 DOI: 10.1080/02643290542000094] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
Impaired semantic memory is ubiquitous in frontotemporal dementia (FTD), including patients with semantic dementia (SD), progressive nonfluent aphasia (PNFA) and nonaphasic FTD patients with a deficit in executive and social functioning (EXEC/SOC). One hypothesis attributes this to the degradation of specific categories of knowledge in semantic memory. This study explores the alternate hypothesis that impaired semantic memory in FTD can also reflect limitations in the categorisation processes that determine object meaning. Patients were taught a novel semantic category under two conditions: rule-based categorisation, where executive resources support the evaluation of specific features to determine category membership; and similarity-based categorisation, where category membership is determined by the overall resemblance of an item to a prototype or recalled exemplars. In the first experiment, patients learned a novel category composed of highly salient features. For SD patients, we found category membership judgment profiles following rule-based and similarity-based training that resembled the performance of control subjects. Categorisation was impaired following rule-based training in PNFA and EXEC/SOC patients. In the second experiment, we modified the category so that membership was determined by less salient features, thus increasing the burden on executive resources. Under these circumstances, SD patients' categorisation profiles continued to resemble those of control subjects, PNFA patients' category judgments were governed by feature salience, and EXEC/SOC patients' judgments were limited by impaired executive resources. These observations suggest that the semantic memory deficit in SD largely reflects degraded feature knowledge for familiar objects, while impaired semantic memory in PNFA and in EXEC/SOC patients largely reflects a deficit in the processes associated with semantic categorisation.
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17
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Wei W, Chen C, Yang T, Zhang H, Zhou X. Dissociated neural correlates of quantity processing of quantifiers, numbers, and numerosities. Hum Brain Mapp 2012; 35:444-54. [PMID: 23019128 DOI: 10.1002/hbm.22190] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2012] [Revised: 08/07/2012] [Accepted: 08/14/2012] [Indexed: 01/29/2023] Open
Abstract
Quantities can be represented using either mathematical language (i.e., numbers) or natural language (i.e., quantifiers). Previous studies have shown that numerical processing elicits greater activation in the brain regions around the intraparietal sulcus (IPS) relative to other semantic processes. However, little research has been conducted to investigate whether the IPS is also critical for the semantic processing of quantifiers in natural language. In this study, 20 adults were scanned with functional magnetic resonance imaging while they performed semantic distance judgment involving six types of materials (i.e., frequency adverbs, quantity pronouns and nouns, animal names, Arabic digits, number words, and dot arrays). Conjunction analyses of brain activation showed that numbers and dot arrays elicited greater activation in the right IPS than did words (i.e., animal names) or quantifiers (i.e., frequency adverbs and quantity pronouns and nouns). Quantifiers elicited more activation in left middle temporal gyrus and inferior frontal gyrus than did numbers and dot arrays. No differences were found between quantifiers and animal names. These findings suggest that, although quantity processing for numbers and dot arrays typically relies on the right IPS region, quantity processing for quantifiers typically relies on brain regions for general semantic processing. Thus, the IPS does not appear to be the only brain region for quantity processing.
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Affiliation(s)
- Wei Wei
- State Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing 100875, People's Republic of China
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18
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Cappelletti M, Butterworth B, Kopelman M. Numeracy skills in patients with degenerative disorders and focal brain lesions: a neuropsychological investigation. Neuropsychology 2011; 26:1-19. [PMID: 22122516 PMCID: PMC3248328 DOI: 10.1037/a0026328] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
Objective: To characterize the numerical profile of patients with acquired brain disorders. Method: We investigated numeracy skills in 76 participants—40 healthy controls and 36 patients with neurodegenerative disorders (Alzheimer dementia, frontotemporal dementia, semantic dementia, progressive aphasia) and with focal brain lesions affecting parietal, frontal, and temporal areas as in herpes simplex encephalitis (HSE). All patients were tested with the same comprehensive battery of paper-and-pencil and computerized tasks assessing numerical abilities and calculation. Degenerative and HSE patients also performed nonnumerical semantic tasks. Results: Our results, based on nonparametric group statistics as well as on the analysis of individual patients, and all highly significant, show that: (a) all patients, including those with parietal lesions—a key brain area for numeracy processing—had intact processing of number quantity; (b) patients with impaired semantic knowledge had much better preserved numerical knowledge; and (c) most patients showed impaired calculation skills, with the exception of most semantic dementia and HSE patients. Conclusion: Our results allow us, for the first time, to characterize the numeracy skills in patients with a variety of neurological conditions and to suggest that the pattern of numerical performance can vary considerably across different neurological populations. Moreover, the selective sparing of calculation skills in most semantic dementia and HSE suggest that numerical abilities are an independent component of the semantic system. Finally, our data suggest that, besides the parietal areas, other brain regions might be critical to the understanding and processing of numerical concepts.
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Morgan B, Gross RG, Clark R, Dreyfuss M, Boller A, Camp E, Liang TW, Avants B, McMillan CT, Grossman M. Some is not enough: quantifier comprehension in corticobasal syndrome and behavioral variant frontotemporal dementia. Neuropsychologia 2011; 49:3532-41. [PMID: 21930136 DOI: 10.1016/j.neuropsychologia.2011.09.005] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2010] [Revised: 07/19/2011] [Accepted: 09/05/2011] [Indexed: 12/12/2022]
Abstract
Quantifiers are very common in everyday speech, but we know little about their cognitive basis or neural representation. The present study examined comprehension of three classes of quantifiers that depend on different cognitive components in patients with focal neurodegenerative diseases. Patients evaluated the truth-value of a sentence containing a quantifier relative to a picture illustrating a small number of familiar objects, and performance was related to MRI grey matter atrophy using voxel-based morphometry. We found that patients with corticobasal syndrome (CBS) and posterior cortical atrophy (PCA) are significantly impaired in their comprehension of cardinal quantifiers (e.g. "At least three birds are on the branch"), due in part to their deficit in quantity knowledge. MRI analyses related this deficit to temporal-parietal atrophy found in CBS/PCA. We also found that patients with behavioral variant frontotemporal dementia (bvFTD) are significantly impaired in their comprehension of logical quantifiers (e.g. "Some of the birds are on the branch"), associated with a simple form of perceptual logic, and this correlated with their deficit on executive measures. This deficit was related to disease in rostral prefrontal cortex in bvFTD. These patients were also impaired in their comprehension of majority quantifiers (e.g. "At least half of the birds are on the branch"), and this too was correlated with their deficit on executive measures. This was related to disease in the basal ganglia interrupting a frontal-striatal loop critical for executive functioning. These findings suggest that a large-scale frontal-parietal neural network plays a crucial role in quantifier comprehension, and that comprehension of specific classes of quantifiers may be selectively impaired in patients with focal neurodegenerative conditions in these areas.
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Affiliation(s)
- Brianna Morgan
- Department of Neurology, University of Pennsylvania, Philadelphia, PA 19104-4283, United States
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20
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Harciarek M, Kertesz A. Primary progressive aphasias and their contribution to the contemporary knowledge about the brain-language relationship. Neuropsychol Rev 2011; 21:271-87. [PMID: 21809067 PMCID: PMC3158975 DOI: 10.1007/s11065-011-9175-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2011] [Accepted: 07/25/2011] [Indexed: 12/12/2022]
Abstract
Primary progressive aphasia (PPA), typically resulting from a neurodegenerative disease such as frontotemporal dementia/Pick Complex or Alzheimer's disease, is a heterogeneous clinical condition characterized by a progressive loss of specific language functions with initial sparing of other cognitive domains. Based on the constellation of symptoms, PPA has been classified into a nonfluent, semantic, or logopenic variant. This review of the literature aims to characterize the speech and language impairment, cognition, neuroimaging, pathology, genetics, and epidemiology associated with each of these variants. Some therapeutic recommendations, theoretical implications, and directions for future research have been also provided.
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Affiliation(s)
- Michał Harciarek
- Department of Social Sciences, Division of Clinical Psychology and Neuropsychology, Institute of Psychology, University of Gdańsk, Bażyńskiego 4, 80-952 Gdańsk, Poland.
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21
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Troiani V, Clark R, Grossman M. Impaired verbal comprehension of quantifiers in corticobasal syndrome. Neuropsychology 2011; 25:159-65. [PMID: 21381823 DOI: 10.1037/a0021448] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
OBJECTIVE Patients with Corticobasal Syndrome (CBS) have atrophy in posterior parietal cortex. This region of atrophy has been previously linked with quantifier comprehension difficulty, but previous studies employed visual stimuli, making it difficult to account for potentially confounding visuospatial deficits in CBS patients. The current study evaluated comprehension of generalized quantifiers using strictly verbal materials. METHOD Non-aphasic CBS patients, a brain-damaged control group (consisting of patients with Alzheimer's disease and frontotemporal dementia), and age-matched healthy controls participated in this study. We assessed familiar temporal, spatial, and monetary domains of verbal knowledge comparatively. Judgment accuracy was only evaluated in statements for which patients demonstrated accurate factual knowledge about the target domain. RESULTS We found that patients with CBS are significantly impaired in their ability to evaluate quantifiers when compared to healthy seniors and a brain-damaged control group, even in this strictly verbal task. This impairment was seen in the vast majority of individual CBS patients. CONCLUSIONS These findings offer additional evidence of quantifier impairment in CBS patients and emphasize that this impairment cannot be attributed to potential visuo spatial processing impairments in patients with parietal disease.
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Affiliation(s)
- Vanessa Troiani
- Department of Neurology, 2 Gibson, Hospital of the University of Pennsylvania, 3400 Spruce St., Philadelphia, PA 19104-4283, USA
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22
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Weinstein J, Koenig P, Gunawardena D, McMillan C, Bonner M, Grossman M. Preserved musical semantic memory in semantic dementia. ACTA ACUST UNITED AC 2011; 68:248-50. [PMID: 21320991 DOI: 10.1001/archneurol.2010.364] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Abstract
OBJECTIVE To understand the scope of semantic impairment in semantic dementia. DESIGN Case study. SETTING Academic medical center. PATIENT A man with semantic dementia, as demonstrated by clinical, neuropsychological, and imaging studies. MAIN OUTCOME MEASURES Music performance and magnetic resonance imaging results. RESULTS Despite profoundly impaired semantic memory for words and objects due to left temporal lobe atrophy, this semiprofessional musician was creative and expressive in demonstrating preserved musical knowledge. CONCLUSION Long-term representations of words and objects in semantic memory may be dissociated from meaningful knowledge in other domains, such as music.
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Affiliation(s)
- Jessica Weinstein
- Department of Neurology, University of Pennsylvania School of Medicine, 3400 Spruce St, Philadelphia, PA 19104-4283, USA
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23
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Bonner MF, Ash S, Grossman M. The new classification of primary progressive aphasia into semantic, logopenic, or nonfluent/agrammatic variants. Curr Neurol Neurosci Rep 2011; 10:484-90. [PMID: 20809401 DOI: 10.1007/s11910-010-0140-4] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
Primary progressive aphasia (PPA), typically resulting from a neurodegenerative disease such as frontotemporal lobar degeneration or Alzheimer's disease, is characterized by a progressive loss of specific language functions with relative sparing of other cognitive domains. Three variants of PPA are now recognized: semantic variant, logopenic variant, and nonfluent/agrammatic variant. We discuss recent work characterizing the neurolinguistic, neuropsychological, imaging and pathologic profiles associated with these variants. Improved reliability of diagnoses will be increasingly important as trials for etiology-specific treatments become available. We also discuss the implications of these syndromes for theories of language function.
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Affiliation(s)
- Michael F Bonner
- Department of Neurology, 2 Gibson, Hospital of the University of Pennsylvania, Philadelphia, PA 19104, USA.
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24
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Koss S, Clark R, Vesely L, Weinstein J, Powers C, Richmond L, Farag C, Gross R, Liang TW, Grossman M. Numerosity impairment in corticobasal syndrome. Neuropsychology 2010; 24:476-92. [PMID: 20604622 DOI: 10.1037/a0018755] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
OBJECTIVE We assessed the representation of numerosity in corticobasal syndrome (CBS), a neurodegenerative condition affecting the parietal lobe. METHOD Patients judged whether a target numerosity (e.g., "3") falls between two bounding numerosities (e.g., "1" and "5"). We manipulated the format for representing numerosity (Arabic numerals or dot arrays), the size of the gap between the two bounding numerosities, the absolute magnitude of the numerosities, and the order for presenting the bounding numerosities. In a subset of patients with available imaging, we related performance to cortical atrophy using voxel-based morphometry. RESULTS CBS patients were significantly impaired overall (65.7% +/- 16.2 correct) compared to healthy seniors (96.6% +/- 2.4 correct), and required three times longer than controls to judge correct stimuli. This deficit was equally evident for Arabic numeral and dot array formats. Controls were significantly slower with smaller gaps than larger gaps, consistent with the greater challenge distinguishing between numerosities that are more similar to each other than very different numerosities. However, CBS patients were equally slow and inaccurate for all gap sizes. Controls also were significantly slower with larger numerosities than smaller numerosities, but CBS patients were equally slow and inaccurate with all numerosity magnitudes. Voxel-based morphometry revealed significant cortical atrophy in parietal and frontal regions in CBS compared to controls, including the intraparietal sulcus. CONCLUSIONS These observations are consistent with the claim that the representation of numerosity is degraded in CBS.
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Affiliation(s)
- Shira Koss
- Department of Neurology, University of Pennsylvania, PA, USA
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25
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Abstract
Primary progressive aphasia (PPA) is a disorder of declining language that is a frequent presentation of neurodegenerative diseases such as frontotemporal lobar degeneration. Three variants of PPA are recognized: progressive nonfluent aphasia, semantic dementia, and logopenic progressive aphasia. In an era of etiology-specific treatments for neurodegenerative conditions, determining the histopathological basis of PPA is crucial. Clinicopathological correlations in PPA emphasize the contributory role of dementia with Pick bodies and other tauopathies, TDP-43 proteinopathies, and Alzheimer disease. These data suggest an association between a specific PPA variant and an underlying pathology, although many cases of PPA are associated with an unexpected pathology. Neuroimaging and biofluid biomarkers are now emerging as important adjuncts to clinical diagnosis. There is great hope that the addition of biomarker assessments to careful clinical examination will enable accurate diagnosis of the pathology associated with PPA during a patient's life, and that such findings will serve as the basis for clinical trials in this spectrum of disease.
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Affiliation(s)
- Murray Grossman
- Department of Neurology, 2 Gibson, Hospital of the University of Pennsylvania, Philadelphia, PA 19104-4283, USA.
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26
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From numbers to letters: Feedback regularization in visual word recognition. Neuropsychologia 2010; 48:1343-55. [DOI: 10.1016/j.neuropsychologia.2009.12.037] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Revised: 12/04/2009] [Accepted: 12/22/2009] [Indexed: 11/17/2022]
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27
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Kertesz A, McMonagle P. Behavior and cognition in corticobasal degeneration and progressive supranuclear palsy. J Neurol Sci 2010; 289:138-43. [DOI: 10.1016/j.jns.2009.08.036] [Citation(s) in RCA: 92] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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28
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Carreiras M, Carr L, Barber HA, Hernandez A. Where syntax meets math: right intraparietal sulcus activation in response to grammatical number agreement violations. Neuroimage 2009; 49:1741-9. [PMID: 19800410 DOI: 10.1016/j.neuroimage.2009.09.058] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2008] [Revised: 09/22/2009] [Accepted: 09/24/2009] [Indexed: 10/20/2022] Open
Abstract
Previous research has shown that the processing of words referring to actions activated motor areas. Here, we show activation of the right intraparietal sulcus, an area that has been associated with quantity processing, when participants are asked to read pairs of words with number agreement violations as opposed to phrases with gender agreement violations or with no violation. In addition, we show activation in the left premotor and left inferior frontal areas when either gender or number agreement is violated. We argue that number violation automatically activates processes linked to quantity processing which are not directly related to language mechanisms.
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Affiliation(s)
- Manuel Carreiras
- Basque Center on Cognition Brain and Language, Donostia-San Sebastián, Spain.
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29
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Whitwell JL, Josephs KA. Voxel-based morphometry and its application to movement disorders. Parkinsonism Relat Disord 2009; 13 Suppl 3:S406-16. [PMID: 18267273 DOI: 10.1016/s1353-8020(08)70039-7] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Voxel-based morphometry (VBM) is an automated technique that assesses patterns of regional grey and white matter atrophy on MRI between two groups of subjects. VBM has been used to assess patterns of regional atrophy in subjects with movement disorders. These studies have demonstrated specific patterns of regional loss in each disorder, compared different movement disorders to look for differences that could be diagnostically useful, and have correlated regions of loss to cognitive and motor deficits in these subjects. This article will review the findings of these studies and discuss the role of VBM in movement disorders.
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30
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Piras F, Marangolo P. Word and number reading in the brain: evidence from a voxel-based lesion-symptom Mapping study. Neuropsychologia 2009; 47:1944-53. [PMID: 19428427 DOI: 10.1016/j.neuropsychologia.2009.03.006] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2008] [Revised: 02/07/2009] [Accepted: 03/04/2009] [Indexed: 10/21/2022]
Abstract
The high incidence of number transcoding deficits in aphasic subjects suggests there is a strong similarity between language and number domains. However, recent single case studies of subjects who showed a dissociation between word and number word transcoding led us to hypothesize that the two types of stimuli are represented independently in the cognitive system. Moreover, it is still unclear whether word and number word reading rely on different brain areas. The present study was designed to investigate this issue in a group of 20 left hemispheric stroke patients who were all tested on Arabic number, number word and word reading (all stimuli were matched for frequency and length). To identify which brain lesions affected performance on the three tasks, we analyzed patients' lesions and behavioural performances using Voxel-based Lesion-symptom Mapping. With this technique, several t-tests can be performed at each voxel to compare behavioural performances of patients with and without a lesion affecting that voxel. Results showed that Arabic number and number word reading involve the same damaged structures, primarily located in the temporo-parietal regions, whereas word reading relies on a frontal network that includes the superior part of Broca's area and the premotor cortex. These data complement the existing neuropsychological literature by suggesting that the already reported dissociations between word and number word reading are supported by distinct cortical networks.
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Affiliation(s)
- Fabrizio Piras
- Laboratorio di Neuroimmagini, Fondazione IRCCS Santa Lucia, Rome, Italy
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31
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Jiang X, Tan Y, Zhou X. Processing the universal quantifier during sentence comprehension: ERP evidence. Neuropsychologia 2009; 47:1799-815. [PMID: 19428412 DOI: 10.1016/j.neuropsychologia.2009.02.020] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2008] [Revised: 01/27/2009] [Accepted: 02/09/2009] [Indexed: 11/19/2022]
Abstract
This study investigates the temporal neural dynamics of processing the Chinese universal quantifier dou during Chinese sentence comprehension using the event-related potential (ERP) technique. Universal quantifier violations were created when the universal quantifier dou (all, every) was misplaced either after a singular object noun phrase (NP) in a Subject-Object-Verb (SOV) sentence (Experiments 1 and 3) or after a singular subject NP in a SVO sentence (Experiment 2). Participants were asked to make semantic plausibility judgment (Experiments 1 and 2) or to comprehend sentences real time followed by a sentence recognition test at the end of the experiment (Experiment 3). Experiment 1 found that quantifier violations elicited a sustained positivity from 400 to 1100ms post-onset of the quantifier and a sustained negativity from 300 to 800ms post-onset of the following verb. Experiment 2 varied the distance between dou and the following verb by the presence or absence of an adverb between them. Again, the sustained positivity was observed on the mismatching quantifier; in addition, a sustained negativity was observed on the word immediately following the quantifier, regardless of whether this word was a verb or adverb. Experiment 3 used the same stimuli as Experiment 1 but with a different task. The quantifier violation elicited anteriorly distributed negativities over different time intervals post-onset of the quantifier. The sustained positivity is interpreted as being associated with an integration process that links the universal quantifier with the preceding entity. The sustained negativity is attributed to a second-pass process to reinterpret the sentence. Other functional interpretations of the ERP components were discussed and ruled out.
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Affiliation(s)
- Xiaoming Jiang
- Department of Psychology, Center for Brain and Cognitive Sciences, Peking University, Beijing, China
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32
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The evolution of numerical cognition: from number neurons to linguistic quantifiers. J Neurosci 2009; 28:11819-24. [PMID: 19005046 DOI: 10.1523/jneurosci.3808-08.2008] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Troiani V, Peelle JE, Clark R, Grossman M. Is it logical to count on quantifiers? Dissociable neural networks underlying numerical and logical quantifiers. Neuropsychologia 2008; 47:104-11. [PMID: 18789346 DOI: 10.1016/j.neuropsychologia.2008.08.015] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2008] [Revised: 08/04/2008] [Accepted: 08/11/2008] [Indexed: 11/25/2022]
Abstract
The present study examined the neural substrate of two classes of quantifiers: numerical quantifiers like "at least three" which require magnitude processing, and logical quantifiers like "some" which can be understood using a simple form of perceptual logic. We assessed these distinct classes of quantifiers with converging observations from two sources: functional imaging data from healthy adults, and behavioral and structural data from patients with corticobasal degeneration who have acalculia. Our findings are consistent with the claim that numerical quantifier comprehension depends on a lateral parietal-dorsolateral prefrontal network, but logical quantifier comprehension depends instead on a rostral medial prefrontal-posterior cingulate network. These observations emphasize the important contribution of abstract number knowledge to the meaning of numerical quantifiers in semantic memory and the potential role of a logic-based evaluation in the service of non-numerical quantifiers.
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Affiliation(s)
- Vanessa Troiani
- Department of Neurology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, United States
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35
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Kempler D, Goral M. Language and Dementia: Neuropsychological Aspects. ANNUAL REVIEW OF APPLIED LINGUISTICS 2008; 28:73-90. [PMID: 21072322 PMCID: PMC2976058 DOI: 10.1017/s0267190508080045] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
This article reviews recent evidence for the relationship between extralinguistic cognitive and language abilities in dementia. A survey of data from investigations of three dementia syndromes (Alzheimer's disease, semantic dementia and progressive nonfluent aphasia) reveals that, more often than not, deterioration of conceptual organization appears associated with lexical impairments, whereas impairments in executive function are associated with sentence- and discourse-level deficits. These connections between extralinguistic functions and language ability also emerge from the literature on cognitive reserve and bilingualism that investigates factors that delay the onset and possibly the progression of neuropsychological manifestation of dementia.
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Halpern C, Clark R, Moore P, Cross K, Grossman M. Too much to count on: impaired very small numbers in corticobasal degeneration. Brain Cogn 2007; 64:144-9. [PMID: 17397978 PMCID: PMC1986671 DOI: 10.1016/j.bandc.2007.01.006] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2006] [Revised: 01/23/2007] [Accepted: 01/29/2007] [Indexed: 12/12/2022]
Abstract
Patients with corticobasal degeneration (CBD) have calculation impairments. This study examined whether impaired number knowledge depends on verbal mediation. We focused particularly on knowledge of very small numbers, where there is a precise relationship between a cardinality and its number concept, but little hypothesized role for verbal mediation. We evaluated accuracy and reaction time (RT) for matching dot arrays and Arabic numerals involving smaller (2-4) and larger (5-9) cardinalities in non-aphasic patients with CBD (n=16), frontotemporal dementia (FTD; n=23), and healthy controls (n=15). CBD were less accurate and slowed at judging smaller Arabic numeral-dot array stimuli compared to FTD patients and controls. Moreover, only CBD showed longer RTs judging successively larger number-dot array pairs among the smaller cardinalities. Difficulty judging very small numbers is impaired in CBD, suggesting degraded representation of precise number knowledge that does not depend on language functioning.
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Affiliation(s)
- Casey Halpern
- Department of Neurology, University of Pennsylvania Medical Center
| | - Robin Clark
- Department of Linguistics, University of Pennsylvania Medical Center
| | - Peachie Moore
- Department of Neurology, University of Pennsylvania Medical Center
| | - Katy Cross
- Department of Neurology, University of Pennsylvania Medical Center
| | - Murray Grossman
- Department of Neurology, University of Pennsylvania Medical Center
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Schroeter ML, Raczka K, Neumann J, Yves von Cramon D. Towards a nosology for frontotemporal lobar degenerations—A meta-analysis involving 267 subjects. Neuroimage 2007; 36:497-510. [PMID: 17478101 DOI: 10.1016/j.neuroimage.2007.03.024] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2007] [Revised: 02/20/2007] [Accepted: 03/14/2007] [Indexed: 12/12/2022] Open
Abstract
Frontotemporal lobar degeneration is the second most common diagnosis of dementia in individuals younger than 65 years. We conducted a systematic and quantitative meta-analysis to examine neural correlates of frontotemporal lobar degeneration and its subtypes and to place the disease in a framework of cognitive neuropsychiatry. MedLine and Current Contents search engines were used to identify functional and anatomical imaging studies investigating frontotemporal lobar degeneration between 1980 and 2005. Studies were included, if they were peer-reviewed, applied internationally recognized diagnostic criteria, were original studies, and had results normalized to a stereotactic space. 19 studies were identified reporting either atrophy or decreases in glucose utilization. Finally, the analysis involved 267 subjects suffering from frontotemporal lobar degeneration and 351 control subjects. A quantitative meta-analysis was performed. Maxima of the studies resulted in activation likelihood estimates. The meta-analysis revealed specific neural networks for each of the three clinically defined subtypes of frontotemporal lobar degeneration, namely frontotemporal dementia, semantic dementia, and progressive non-fluent aphasia. Networks did not overlap as shown by a conjunction analysis, and they corresponded to clinical characteristics. The study relates the clinical features of each subtype of frontotemporal lobar degeneration specifically to its neural substrate. By 'triple dissociating' frontotemporal lobar degenerations into three clinicoanatomical prototypes, the study contributes to placing these disorders in cognitive neuropsychiatry and suggests a respective nosology.
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Affiliation(s)
- Matthias L Schroeter
- Max-Planck-Institute for Human Cognitive and Brain Sciences, Stephanstr. 1A, 04103 Leipzig, Germany.
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Piazza M, Pinel P, Le Bihan D, Dehaene S. A Magnitude Code Common to Numerosities and Number Symbols in Human Intraparietal Cortex. Neuron 2007; 53:293-305. [PMID: 17224409 DOI: 10.1016/j.neuron.2006.11.022] [Citation(s) in RCA: 517] [Impact Index Per Article: 30.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2006] [Revised: 10/19/2006] [Accepted: 11/21/2006] [Indexed: 01/29/2023]
Abstract
Activation of the horizontal segment of the intraparietal sulcus (hIPS) has been observed in various number-processing tasks, whether numbers were conveyed by symbolic numerals (digits, number words) or by nonsymbolic displays (dot patterns). This suggests an abstract coding of numerical magnitude. Here, we critically tested this hypothesis using fMRI adaptation to demonstrate notation-independent coding of numerical quantity in the hIPS. Once subjects were adapted either to dot patterns or to Arabic digits, activation in the hIPS and in frontal regions recovered in a distance-dependent fashion whenever a new number was presented, irrespective of notation changes. This remained unchanged when analyzing the hIPS peaks from an independent localizer scan of mental calculation. These results suggest an abstract coding of approximate number common to dots, digits, and number words. They support the idea that symbols acquire meaning by linking neural populations coding symbol shapes to those holding nonsymbolic representations of quantities.
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Affiliation(s)
- Manuela Piazza
- Institut National de la Santé et de la Recherche Médicale (INSERM), Cognitive Neuroimaging Unit, Service Hospitalier Frédéric Joliot, F-91401 Orsay, France.
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McMillan CT, Clark R, Moore P, Grossman M. Quantifier comprehension in corticobasal degeneration. Brain Cogn 2006; 62:250-60. [PMID: 16949714 DOI: 10.1016/j.bandc.2006.06.005] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2006] [Revised: 06/16/2006] [Accepted: 06/23/2006] [Indexed: 12/12/2022]
Abstract
In this study, we investigated patients with focal neurodegenerative diseases to examine a formal linguistic distinction between classes of generalized quantifiers, like "some X" and "less than half of X." Our model of quantifier comprehension proposes that number knowledge is required to understand both first-order and higher-order quantifiers. The present results demonstrate that corticobasal degeneration (CBD) patients, who have number knowledge impairments but little evidence for a deficit understanding other aspects of language, are impaired in their comprehension of quantifiers relative to healthy seniors, Alzheimer's disease (AD) and frontotemporal dementia (FTD) patients [F(3,77)=4.98; p<.005]. Moreover, our model attempts to honor a distinction in complexity between classes of quantifiers such that working memory is required to comprehend higher-order quantifiers. Our results support this distinction by demonstrating that FTD and AD patients, who have working memory limitations, have greater difficulty understanding higher-order quantifiers relative to first-order quantifiers [F(1,77)=124.29; p<.001]. An important implication of these findings is that the meaning of generalized quantifiers appears to involve two dissociable components, number knowledge and working memory, which are supported by distinct brain regions.
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Affiliation(s)
- Corey T McMillan
- Department of Neurology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA
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Abstract
OBJECTIVES Visuospatial deficits have been occasionally reported but never systematically studied in atypical parkinsonian syndromes. The interpretation of existing studies is complicated by the possible influence of motor and frontal executive deficits. Moreover, no attempt has been made to distinguish visuoperceptual from visuospatial tasks. The aim of the present study was to assess visuoperceptual and visuospatial abilities in three atypical parkinsonian syndromes while minimising the influence of confounding variables. METHODS Twenty patients with multiple system atrophy (MSA), 43 with progressive supranuclear palsy (PSP), and 25 with corticobasal degeneration (CBD) as well as 30 healthy age matched controls were examined with the Visual Object and Space Perception Battery (VOSP). RESULTS Visuospatial functions were intact in MSA patients. PSP patients showed mild deficits related to general cognitive decline and the severity of oculomotor symptoms. The CBD group showed the most pronounced deficits, with spatial tasks more impaired than object based tasks. Performance on object based, but not spatial, tasks was related to general cognitive status. The extent of the visuospatial impairment could not be predicted from disease duration or severity. CONCLUSION Visuospatial functions are not consistently impaired in atypical parkinsonian syndromes. The degree and pattern of impairment varies across the diseases, suggesting that the observed deficits could have a different neural basis in each condition. The distinction between the object based ("ventral stream") and the space oriented ("dorsal stream") processing might be useful in the interpretation of visuospatial deficits in parkinsonian syndromes, especially in CBD.
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Affiliation(s)
- T H Bak
- MRC Cognition and Brain Sciences Unit, Cambridge CB2 2EF, UK
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Whitwell JL, Jack CR. Comparisons between Alzheimer disease, frontotemporal lobar degeneration, and normal aging with brain mapping. Top Magn Reson Imaging 2005; 16:409-25. [PMID: 17088691 DOI: 10.1097/01.rmr.0000245457.98029.e1] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Alzheimer disease (AD) and frontotemporal lobar degeneration (FTLD) are both common degenerative dementias in the under 65 age group. Although clinical criteria have been defined for both diseases, there is considerable overlap in clinical features, and hence, diagnosis still can be very difficult particularly in the early stages of the disease. As a result, there has been increasing interest in using magnetic resonance imaging to better characterize these diseases and to aid in diagnosis. Voxel-based morphometry (VBM) is an automated technique that assesses patterns of regional gray matter atrophy on magnetic resonance imaging between 2 groups of subjects. It is unbiased in that it looks throughout the whole brain and does not require any a priori assumptions concerning which structures to assess, giving it a significant advantage over traditional region of interest-based methods. Voxel-based morphometry has been widely used to assess patterns of regional atrophy in subjects with AD and FTLD. These studies have demonstrated specific patterns of regional loss in both diseases, compared the 2 diseases to look for differences that could be diagnostically useful, and have correlated regions of gray matter loss to cognitive and behavioral deficits in these subjects. This article will review the findings of these studies and discuss the role of VBM in these neurodegenerative diseases.
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Grossman M, Farmer J, Leight S, Work M, Moore P, Van Deerlin V, Pratico D, Clark CM, Coslett HB, Chatterjee A, Gee J, Trojanowski JQ, Lee VMY. Cerebrospinal fluid profile in frontotemporal dementia and Alzheimer's disease. Ann Neurol 2005; 57:721-9. [PMID: 15852395 DOI: 10.1002/ana.20477] [Citation(s) in RCA: 176] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
We assessed cerebrospinal fluid (CSF) levels of tau and other biomarkers of neurodegenerative disease. CSF tau levels vary widely in reports of frontotemporal dementia (FTD). CSF samples were assayed for tau, amyloid beta1-42 (A1-42), and the isoprostane 8,12-iso-iPF2a-VI (iP) prospectively in 64 patients with FTD, retrospectively in 26 autopsied cases with FTD or Alzheimer's disease (AD), and in 13 healthy seniors. To validate our observations in vivo, we correlated CSF tau levels with cortical atrophy in 17 FTD patients using voxel-based morphometry analyses of high-resolution magnetic resonance imaging. CSF levels of tau, Abeta1-42, and iP differed significantly in FTD compared with AD. Individual patient analyses showed that 34% of FD patients had significantly low levels of CSF tau, although this was never seen in AD. A discriminant analysis based on CSF levels of tau, Abeta1-42, and iP was able to classify 88.5% of these patients in a manner that corresponds to their clinical or autopsy diagnosis. Magnetic resonance imaging studies showed that CSF tau levels correlate significantly with right frontal and left temporal cortical atrophy, brain regions known to be atrophic in patients with autopsy-proved FTD. We conclude that CSF tau levels are significantly reduced in many patients with FTD.
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Affiliation(s)
- Murray Grossman
- Department of Neurology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104-4283, USA.
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McMillan CT, Clark R, Moore P, Devita C, Grossman M. Neural basis for generalized quantifier comprehension. Neuropsychologia 2005; 43:1729-37. [PMID: 16154448 DOI: 10.1016/j.neuropsychologia.2005.02.012] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2004] [Revised: 02/03/2005] [Accepted: 02/15/2005] [Indexed: 10/25/2022]
Abstract
Generalized quantifiers like "all cars" are semantically well understood, yet we know little about their neural representation. Our model of quantifier processing includes a numerosity device, operations that combine number elements and working memory. Semantic theory posits two types of quantifiers: first-order quantifiers identify a number state (e.g. "at least 3") and higher-order quantifiers additionally require maintaining a number state actively in working memory for comparison with another state (e.g. "less than half"). We used BOLD fMRI to test the hypothesis that all quantifiers recruit inferior parietal cortex associated with numerosity, while only higher-order quantifiers recruit prefrontal cortex associated with executive resources like working memory. Our findings showed that first-order and higher-order quantifiers both recruit right inferior parietal cortex, suggesting that a numerosity component contributes to quantifier comprehension. Moreover, only probes of higher-order quantifiers recruited right dorsolateral prefrontal cortex, suggesting involvement of executive resources like working memory. We also observed activation of thalamus and anterior cingulate that may be associated with selective attention. Our findings are consistent with a large-scale neural network centered in frontal and parietal cortex that supports comprehension of generalized quantifiers.
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Affiliation(s)
- Corey T McMillan
- Department of Neurology, University of Pennsylvania Medical Center, Philadelphia, PA 19104-4283, USA
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Halpern C, Clark R, Moore P, Antani S, Colcher A, Grossman M. Verbal mediation of number knowledge: Evidence from semantic dementia and corticobasal degeneration. Brain Cogn 2004; 56:107-15. [PMID: 15380881 DOI: 10.1016/j.bandc.2004.07.001] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/16/2004] [Indexed: 10/26/2022]
Abstract
Patients with corticobasal degeneration (CBD) appear to have impaired number knowledge. We examined the nature of their number deficit while we tested the hypothesis that comprehension of larger numbers depends in part on verbal mediation. We evaluated magnitude judgments and performance on number conservation measures rooted in Piagetian theory in nonaphasic patients with CBD (n=13) and patients with a fluent form of progressive aphasia known as semantic dementia (SD; n=15). We manipulated the numbers of the arrays and the visual-spatial properties of the stimuli being compared during magnitude judgments and Piagetian conservation measures. CBD patients were consistently impaired judging the magnitudes of larger numbers (4-9), while they had minimal difficulty with smaller numbers (magnitudes < or = 3). By comparison, SD patients performed all measures of number knowledge at a ceiling level regardless of number magnitude. Neither patient group was significantly impacted by manipulations of the spatial properties of the stimuli. CBD patients' impairment with larger numbers despite minimal aphasia, and SD patients' intact performance despite an aphasia, challenge the proposal that understanding larger numbers depends on verbal mediation.
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Affiliation(s)
- Casey Halpern
- Department of Neurology, University of Pennsylvania, USA
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