Murray Grossman

University of Pennsylvania, Filadelfia, Pennsylvania, United States

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Publications (317)1670.78 Total impact

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    ABSTRACT: To examine the influence of occupational attainment and education on survival in autopsy-confirmed cases of frontotemporal lobar degeneration (FTLD) and Alzheimer disease (AD). We performed a retrospective chart review of 83 demographically matched, autopsy-confirmed FTLD (n = 34) and AD (n = 49) cases. Each patient's primary occupation was classified and ranked. Level of education was recorded in years. Survival was defined as time from symptom onset until death. Linear regression was used to test for associations among occupational attainment, education, and patient survival. Median survival was 81 months for FTLD and 95 months for AD. Years of education and occupational attainment were similar for both groups. We found that higher occupational attainment was associated with longer survival in FTLD but not AD. Our findings suggest that higher occupational attainment is associated with longer survival in autopsy-confirmed FTLD. The identification of protective factors associated with FTLD survival has important implications for estimates of prognosis and longitudinal studies such as treatment trials. © 2015 American Academy of Neurology.
    Neurology 04/2015; DOI:10.1212/WNL.0000000000001595 · 8.30 Impact Factor
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    ABSTRACT: To use in vivo neuroimaging and postmortem neuropathologic analysis in C9orf72 repeat expansion patients to investigate the hypothesis that C9orf72 promoter hypermethylation is neuroprotective and regionally selective. Twenty patients with a C9orf72 repeat expansion participating in a high-resolution MRI scan and a clinical examination and a subset of patients (n = 11) were followed longitudinally with these measures. Gray matter (GM) density was related to C9orf72 promoter hypermethylation using permutation-based testing. Regional neuronal loss was measured in an independent autopsy series (n = 35) of C9orf72 repeat expansion patients. GM analysis revealed that hippocampus, frontal cortex, and thalamus are associated with hypermethylation and thus appear to be relatively protected from mutant C9orf72. Neuropathologic analysis demonstrated an association between reduced neuronal loss and hypermethylation in hippocampus and frontal cortex. Longitudinal neuroimaging revealed that hypermethylation is associated with reduced longitudinal decline in GM regions protected by hypermethylation and longitudinal neuropsychological assessment demonstrated that longitudinal decline in verbal recall is protected by hypermethylation. These cross-sectional and longitudinal neuroimaging studies, along with neuropathologic validation studies, provide converging evidence for neuroprotective properties of C9orf72 promoter hypermethylation. These findings converge with prior postmortem studies suggesting that C9orf72 promoter hypermethylation may be a neuroprotective target for drug discovery. © 2015 American Academy of Neurology.
    Neurology 03/2015; 84(16). DOI:10.1212/WNL.0000000000001495 · 8.30 Impact Factor
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    ABSTRACT: Up to half of patients with amyotrophic lateral sclerosis (ALS) may have cognitive difficulty, but most cognitive measures are confounded by a motor component. Studies relating impaired cognition in ALS to disease in gray matter and white matter are rare. Our objective was to assess executive function in patients with ALS using a simple, untimed measure with minimal motor demands, and to relate performance to structural disease. We gave the Visual-Verbal Test to 56 patients with ALS and 29 matched healthy controls. This brief, untimed measure of cognitive flexibility first assesses participants' ability to identify a feature shared by 3 of 4 simple geometric designs. The participants' cognitive flexibility is challenged when they are next asked to identify a different feature shared by another combination of 3 of the same 4 geometric designs. In a subset of 17 patients who underwent magnetic resonance imaging, regression analyses related test performance to gray matter atrophy and reduced white matter fractional anisotropy. The patients with ALS showed significant impairment in cognitive flexibility (P<0.01), with 48.2% making an error on the test. Regression analyses related impaired cognitive flexibility to gray matter atrophy in inferior frontal and insular regions, and to reduced fractional anisotropy in white matter projections in the inferior fronto-occipital and uncinate fasciculi and corpus callosum. Our patients with ALS had impaired cognitive flexibility on an untimed measure with minimal motor demands, a finding related in part to a large-scale frontal network that is degraded in ALS.
    Cognitive and behavioral neurology: official journal of the Society for Behavioral and Cognitive Neurology 03/2015; 28(1):17-26. DOI:10.1097/WNN.0000000000000049 · 1.14 Impact Factor
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    ABSTRACT: Amyotrophic lateral sclerosis (ALS) is a devastating neurological disease with no effective treatment. Here we report the results of a moderate-scale sequencing study aimed at identifying new genes contributing to predisposition for ALS. We performed whole exome sequencing of 2,874 ALS patients and compared them to 6,405 controls. Several known ALS genes were found to be associated, and the non-canonical IκB kinase family TANK-Binding Kinase 1 (TBK1) was identified as an ALS gene. TBK1 is known to bind to and phosphorylate a number of proteins involved in innate immunity and autophagy, including optineurin (OPTN) and p62 (SQSTM1/sequestosome), both of which have also been implicated in ALS. These observations reveal a key role of the autophagic pathway in ALS and suggest specific targets for therapeutic intervention. Copyright © 2015, American Association for the Advancement of Science.
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    ABSTRACT: Human thought and language rely on the brain's ability to combine conceptual information. This fundamental process supports the construction of complex concepts from basic constituents. For example, both "jacket" and "plaid" can be represented as individual concepts, but they can also be integrated to form the more complex representation "plaid jacket." Although this process is central to the expression and comprehension of language, little is known about its neural basis. Here we present evidence for a neuroanatomic model of conceptual combination from three experiments. We predicted that the highly integrative region of heteromodal association cortex in the angular gyrus would be critical for conceptual combination, given its anatomic connectivity and its strong association with semantic memory in functional neuroimaging studies. Consistent with this hypothesis, we found that the process of combining concepts to form meaningful representations specifically modulates neural activity in the angular gyrus of healthy adults, independent of the modality of the semantic content integrated. We also found that individual differences in the structure of the angular gyrus in healthy adults are related to variability in behavioral performance on the conceptual combination task. Finally, in a group of patients with neurodegenerative disease, we found that the degree of atrophy in the angular gyrus is specifically related to impaired performance on combinatorial processing. These converging anatomic findings are consistent with a critical role for the angular gyrus in conceptual combination. Copyright © 2015 the authors 0270-6474/15/353276-09$15.00/0.
    The Journal of Neuroscience : The Official Journal of the Society for Neuroscience 02/2015; 35(7):3276-84. DOI:10.1523/JNEUROSCI.3446-14.2015 · 6.75 Impact Factor
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    ABSTRACT: For social interactions to be successful, individuals must establish shared mental representations that allow them to reach a common understanding and "get on the same page". We refer to this process as social coordination. While examples of social coordination are ubiquitous in daily life, relatively little is known about the neuroanatomic basis of this complex behavior. This is particularly true in a language context, as previous studies have used overly complex paradigms to study this. Although traditional views of language processing and the recent interactive-alignment account of conversation focus on peri-Sylvian regions, our model of social coordination predicts prefrontal involvement. To test this hypothesis, we examine the neural basis of social coordination during conversational exchanges in non-aphasic patients with behavioral variant frontotemporal degeneration (bvFTD). bvFTD patients show impairments in executive function and social comportment due to disease in frontal and anterior temporal regions. To investigate social coordination in bvFTD, we developed a novel language-based task that assesses patients' ability to convey an object's description to a conversational partner. Experimental conditions manipulated the amount of information shared by the participant and the conversational partner, and the associated working memory demands. Our results indicate that, although patients did not have difficulty identifying the features of the objects, they did produce descriptions that included insufficient or inappropriate adjectives and thus struggled to communicate effectively. Impaired performance was related to gray matter atrophy particularly in medial prefrontal and orbitofrontal cortices. Our findings suggest an important role for non-language brain areas that belong to a large-scale neurocognitive network for social coordination. Copyright © 2015. Published by Elsevier Ltd.
    Neuropsychologia 01/2015; 69. DOI:10.1016/j.neuropsychologia.2015.01.028 · 3.45 Impact Factor
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    ABSTRACT: The scope of reference of a word's meaning can be highly variable. We present a novel paradigm to investigate the flexible interpretation of word meaning. We focus on quantifiers such as "many" or "few," a class of words that depends on number knowledge but can be interpreted in a flexible manner. Healthy young adults performed a truth value judgment task on pictorial arrays of varying amounts of blue and yellow circles, deciding whether the sentence "Many/few of the circles are yellow" was an adequate description of the stimulus. The study consisted of two experiments, one focusing on "many," one on "few." Each experiment had three blocks. In a first "baseline" block, each individual's criterion for "many" and "few" was assessed. In a second "adaptation" block, subjects received feedback about their decisions that was different from their initial judgments in an effort to evaluate the flexibility of a subject's interpretation. A third "test" block assessed whether adaptation of quantifier meaning induced in block 2 then was generalized to alter a subject's baseline meaning for "many" and "few." In Experiment 1, a proportion of yellow circles as small as 40% was reinforced as "many"; in Experiment 2, a proportion of yellow circles as large as 60% was reinforced as "few." Subjects learned the new criterion for "many" in Experiment 1, which also affected their criterion for "few" although it had never been mentioned. Likewise, in Experiment 2, subjects changed their criterion for "few," with a comparable effect on the criterion for "many" which was not mentioned. Thus, the meaning of relational quantifiers like "many" and "few" is flexible and can be adapted. Most importantly, adapting the criterion for one quantifier (e.g., "many") also appeared to affect the reciprocal quantifier (in this case, "few"). Implications of this result for psychological interventions and for investigations of the neurobiology of the language-number interface are discussed.
    Frontiers in Psychology 01/2015; 6:441. DOI:10.3389/fpsyg.2015.00441 · 2.80 Impact Factor
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    ABSTRACT: Frontotemporal lobar degeneration (FTLD) comprises two main classes of neurodegenerative diseases characterized by neuronal/glial proteinaceous inclusions (i.e., proteinopathies) including tauopathies (i.e., FTLD-Tau) and TDP-43 proteinopathies (i.e., FTLD-TDP) while other very rare forms of FTLD are known such as FTLD with FUS pathology (FTLD-FUS). This review focuses mainly on FTLD-Tau and FLTD-TDP, which may present as several clinical syndromes: a behavioral/dysexecutive syndrome (behavioral variant frontotemporal dementia); language disorders (primary progressive aphasia variants); and motor disorders (amyotrophic lateral sclerosis, corticobasal syndrome, progressive supranuclear palsy syndrome). There is considerable heterogeneity in clinical presentations of underlying neuropathology and current clinical criteria do not reliably predict underlying proteinopathies ante-mortem. In contrast, molecular etiologies of hereditary FTLD are consistently associated with specific proteinopathies. These include MAPT mutations with FTLD-Tau and GRN, C9orf72, VCP and TARDBP with FTLD-TDP. The last decade has seen a rapid expansion in our knowledge of the molecular pathologies associated with this clinically and neuropathologically heterogeneous group of FTLD diseases. Moreover, in view of current limitations to reliably diagnose specific FTLD neuropathologies prior to autopsy, we summarize the current state of the science in FTLD biomarker research including neuroimaging, biofluid and genetic analyses. We propose that combining several of these biomarker modalities will improve diagnostic specificity in FTLD through a personalized medicine approach. The goals of these efforts are to enhance power for clinical trials focused on slowing or preventing progression of spread of tau, TDP-43 and other FTLD-associated pathologies and work toward the goal of defining clinical endophenotypes of FTD.
    Acta Neuropathologica 12/2014; 129(4). DOI:10.1007/s00401-014-1380-1 · 9.78 Impact Factor
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    ABSTRACT: Quantitative examinations of speech production in amyotrophic lateral sclerosis (ALS) are rare. To identify language features minimally confounded by a motor disorder, we investigated linguistic and motor sources of impaired sentence expression in ALS, and we related deficits to gray matter (GM) and white matter (WM) MRI abnormalities. We analyzed a semi-structured speech sample in 26 ALS patients and 19 healthy seniors for motor- and language-related deficits. Regression analyses related grammaticality to GM atrophy and reduced WM fractional anisotropy (FA). Results demonstrated that ALS patients were impaired relative to controls on quantity of speech, speech rate, speech articulation errors, and grammaticality. Speech rate and articulation errors were related to the patients' motor impairment, while grammatical difficulty was independent of motor difficulty. This was confirmed in subgroups without dysarthria and without executive deficits. Regressions related grammatical expression to GM atrophy in left inferior frontal and anterior temporal regions and to reduced FA in superior longitudinal and inferior frontal-occipital fasciculi. In conclusion, patients with ALS exhibit multifactorial deficits in sentence expression. They demonstrate a deficit in grammatical expression that is independent of their motor disorder. Impaired grammatical expression is related to disease in a network of brain regions associated with syntactic processing.
    Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration 12/2014; DOI:10.3109/21678421.2014.974617 · 2.59 Impact Factor
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    ABSTRACT: To relate changes in fractional anisotropy associated with behavioral variant frontotemporal dementia to measures of apathy and disinhibition. Apathy and disinhibition are the 2 most common behavioral features of behavioral variant frontotemporal dementia, and these symptoms are associated with accelerated patient decline and caregiver stress. However, little is known about how white matter disease contributes to these symptoms. We collected neuropsychiatric data, volumetric magnetic resonance imaging, and diffusion-weighted imaging in 11 patients who met published criteria for behavioral variant frontotemporal dementia and had an autopsy-validated cerebrospinal fluid profile consistent with frontotemporal lobar degeneration. We also collected imaging data on 34 healthy seniors for analyses defining regions of disease in the patients. We calculated and analyzed fractional anisotropy with a white matter tract-specific method. This approach uses anatomically guided data reduction to increase sensitivity, and localizes results within canonically defined tracts. We used nonparametric, cluster-based statistical analysis to relate fractional anisotropy to neuropsychiatric measures of apathy and disinhibition. The patients with behavioral variant frontotemporal dementia had widespread reductions in fractional anisotropy in anterior portions of frontal and temporal white matter, compared to the controls. Fractional anisotropy correlated with apathy in the left uncinate fasciculus and with disinhibition in the right corona radiata. In patients with behavioral variant frontotemporal dementia, apathy and disinhibition are associated with distinct regions of white matter disease. The implicated fiber tracts likely support frontotemporal networks that are involved in goal-directed behavior.
    Cognitive and behavioral neurology: official journal of the Society for Behavioral and Cognitive Neurology 12/2014; 27(4):206-14. DOI:10.1097/WNN.0000000000000044 · 1.14 Impact Factor
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    ABSTRACT: Segmenting and quantifying gliomas from MRI is an important task for diagnosis, planning intervention, and for tracking tumor changes over time. However, this task is complicated by the lack of prior knowledge concerning tumor location, spatial extent, shape, possible displacement of normal tissue, and intensity signature. To accommodate such complications, we introduce a framework for supervised segmentation based on multiple modality intensity, geometry, and asymmetry feature sets. These features drive a supervised whole-brain and tumor segmentation approach based on random forest-derived probabilities. The asymmetry-related features (based on optimal symmetric multimodal templates) demonstrate excellent discriminative properties within this framework. We also gain performance by generating probability maps from random forest models and using these maps for a refining Markov random field regularized probabilistic segmentation. This strategy allows us to interface the supervised learning capabilities of the random forest model with regularized probabilistic segmentation using the recently developed ANTsR package-a comprehensive statistical and visualization interface between the popular Advanced Normalization Tools (ANTs) and the R statistical project. The reported algorithmic framework was the top-performing entry in the MICCAI 2013 Multimodal Brain Tumor Segmentation challenge. The challenge data were widely varying consisting of both high-grade and low-grade glioma tumor four-modality MRI from five different institutions. Average Dice overlap measures for the final algorithmic assessment were 0.87, 0.78, and 0.74 for "complete", "core", and "enhanced" tumor components, respectively.
    Neuroinformatics 11/2014; DOI:10.1007/s12021-014-9245-2 · 3.10 Impact Factor
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    ABSTRACT: C9orf72 promoter hypermethylation inhibits the accumulation of pathologies which have been postulated to be neurotoxic. We tested here whether C9orf72 hypermethylation is associated with prolonged disease in C9orf72 mutation carriers. C9orf72 methylation was quantified from brain or blood using methylation-sensitive restriction enzyme digest-qPCR in a cross-sectional cohort of 118 C9orf72 repeat expansion carriers and 19 non-carrier family members. Multivariate regression models were used to determine whether C9orf72 hypermethylation was associated with age at onset, disease duration, age at death, or hexanucleotide repeat expansion size. Permutation analysis was performed to determine whether C9orf72 methylation is heritable. We observed a high correlation between C9orf72 methylation across tissues including cerebellum, frontal cortex, spinal cord and peripheral blood. While C9orf72 methylation was not significantly different between ALS and FTD and did not predict age at onset, brain and blood C9orf72 hypermethylation was associated with later age at death in FTD (brain: β = 0.18, p = 0.006; blood: β = 0.15, p < 0.001), and blood C9orf72 hypermethylation was associated with longer disease duration in FTD (β = 0.03, p = 0.007). Furthermore, C9orf72 hypermethylation was associated with smaller hexanucleotide repeat length (β = -16.69, p = 0.033). Finally, analysis of pedigrees with multiple mutation carriers demonstrated a significant association between C9orf72 methylation and family relatedness (p < 0.0001). C9orf72 hypermethylation is associated with prolonged disease in C9orf72 repeat expansion carriers with FTD. The attenuated clinical phenotype associated with C9orf72 hypermethylation suggests that slower clinical progression in FTD is associated with reduced expression of mutant C9orf72. These results support the hypothesis that expression of the hexanucleotide repeat expansion is associated with a toxic gain of function.
    Acta Neuropathologica 11/2014; DOI:10.1007/s00401-014-1365-0 · 9.78 Impact Factor
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    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 correlated with gray matter atrophy in parietal regions. Moreover, a numeral-dots transcoding task showed that CBS/PCA patients are 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.
    Neuropsychologia 09/2014; 64. DOI:10.1016/j.neuropsychologia.2014.09.030 · 3.45 Impact Factor
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    Lauren Massimo, Lois K Evans, Murray Grossman
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    ABSTRACT: Apathy, a reduction in goal-directed behavior (GDB), affects 90% of individuals with behavioral variant frontotemporal degeneration, which is a common cause of early onset neurodegenerative disease. The cognitive and neural impairments associated with apathy make it difficult to initiate, plan, and self-motivate activities toward a specific goal, such as dressing or bathing. These impairments are associated with significant decline in functional ability, caregiver burden, and increased cost of care due to early institutionalization. The current article reviews the evidence suggesting that apathy arises from the interruption of one or any combination of three GDB processes: initiation, planning, and motivation. From this perspective, three subtypes of apathy related to dysfunction at the level of GDB and the corresponding neuroanatomy are explored. Further research is required to confirm and measure these subtypes of apathy for use in clinical and research settings. A more precise classification of apathy by subtype will allow implementation of the most appropriate person-centered, individualized therapy. [Journal of Gerontological Nursing, xx(x), xx-xx.].
    Journal of Gerontological Nursing 09/2014; 40(10):1-8. DOI:10.3928/00989134-20140827-01 · 0.62 Impact Factor
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    ABSTRACT: Frontotemporal dementia (FTD) is a clinically and pathologically heterogeneous neurodegenerative disease that can result from either frontotemporal lobar degeneration (FTLD) or Alzheimer's disease (AD) pathology. It is critical to establish statistically powerful biomarkers that can achieve substantial cost-savings and increase the feasibility of clinical trials. We assessed three broad categories of neuroimaging methods to screen underlying FTLD and AD pathology in a clinical FTD series: global measures (e.g., ventricular volume), anatomical volumes of interest (VOIs) (e.g., hippocampus) using a standard atlas, and data-driven VOIs using Eigenanatomy. We evaluated clinical FTD patients (N = 93) with cerebrospinal fluid, gray matter (GM) magnetic resonance imaging (MRI), and diffusion tensor imaging (DTI) to assess whether they had underlying FTLD or AD pathology. Linear regression was performed to identify the optimal VOIs for each method in a training dataset and then we evaluated classification sensitivity and specificity in an independent test cohort. Power was evaluated by calculating minimum sample sizes required in the test classification analyses for each model. The data-driven VOI analysis using a multimodal combination of GM MRI and DTI achieved the greatest classification accuracy (89% sensitive and 89% specific) and required a lower minimum sample size (N = 26) relative to anatomical VOI and global measures. We conclude that a data-driven VOI approach using Eigenanatomy provides more accurate classification, benefits from increased statistical power in unseen datasets, and therefore provides a robust method for screening underlying pathology in FTD patients for entry into clinical trials. Hum Brain Mapp, 2014. © 2014 Wiley Periodicals, Inc.
    Human Brain Mapping 09/2014; 35(9). DOI:10.1002/hbm.22515 · 6.92 Impact Factor
  • Murray Grossman
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    ABSTRACT: Primary progressive aphasia (PPA) is a progressive disorder of language that is increasingly recognised as an important presentation of a specific spectrum of neurodegenerative conditions. In an era of etiologically specific treatments for neurodegenerative conditions, it is crucial to establish the histopathologic basis for PPA. In this review, I discuss biomarkers for identifying the pathology underlying PPA. Clinical syndromes suggest a probabilistic association between a specific PPA variant and an underlying pathology, but there are also many exceptions. A considerable body of work with biomarkers is now emerging as an important addition to clinical diagnosis. I review genetic, neuroimaging and biofluid studies that can help determine the pathologic basis for PPA. Together with careful clinical examination, there is great promise that supplemental biomarker assessments will lead to accurate diagnosis of the pathology associated with PPA during life and serve as the basis for clinical trials in this spectrum of disease.
    Aphasiology 09/2014; 28(8-9):922-940. DOI:10.1080/02687038.2014.929631 · 1.73 Impact Factor
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    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.
    Frontiers in Human Neuroscience 08/2014; 8. DOI:10.3389/fnhum.2014.00610 · 2.90 Impact Factor
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    ABSTRACT: Corticobasal syndrome (CBS) is characterized by asymmetric involuntary movements including rigidity, tremor, dystonia, and myoclonus, and often associated with apraxia, cortical sensory deficits, and alien limb phenomena. Additionally, there are various nonmotor (cognitive and language) deficits. CBS is associated with several distinct histopathologies, including corticobasal degeneration, other forms of tau-related frontotemporal lobar degeneration such as progressive supranuclear palsy, and Alzheimer disease. Accurate antemortem diagnosis of underlying pathology in CBS is challenging, though certain clinical and imaging findings may be helpful. Five recent advances in the understanding of CBS are reviewed, including clinical and pathologic features, imaging and CSF biomarkers, the role of specific genes, and the concept of a spectrum of tauopathies.
    Nature Clinical Practice Neurology 08/2014; 4(4):304-312. DOI:10.1212/CPJ.0000000000000026 · 7.64 Impact Factor
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    ABSTRACT: Objective: Autopsy studies show widespread pathology in amyotrophic lateral sclerosis (ALS), but clinical surveys of multisystem disease in ALS are rare. We investigated ALS-Plus syndrome, an understudied group of patients with clinical features extending beyond pyramidal and neuromuscular systems with or without cognitive/behavioral deficits. Methods: In a large, consecutively-ascertained cohort of 550 patients with ALS, we documented atypical clinical manifestations. Genetic screening for C9orf72 hexanucleotide expansions was performed in 343 patients, and SOD1, TARDBP, and VCP were tested in the subgroup of patients with a family history of ALS. Gray matter and white matter imaging was available in a subgroup of 30 patients. Results: Seventy-five (13.6%) patients were identified with ALS-Plus syndrome. We found disorders of ocular motility, cerebellar, extrapyramidal and autonomic functioning. Relative to those without ALS-Plus, cognitive impairment (8.0% vs 2.9%, p = 0.029), bulbar-onset (49.3% vs 23.2%, p < 0.001), and pathogenic mutations (20.0% vs 8.4%, p = 0.015) were more than twice as common in ALS-Plus. Survival was significantly shorter in ALS-Plus (29.66 months vs 42.50 months, p = 0.02), regardless of bulbar-onset or mutation status. Imaging revealed significantly greater cerebellar and cerebral disease in ALS-Plus compared to those without ALS-Plus. Conclusions: ALS-Plus syndrome is not uncommon, and the presence of these atypical features is consistent with neuropathological observations that ALS is a multisystem disorder. ALS-Plus syndrome is associated with increased risk for poor survival and the presence of a pathogenic mutation. (C) 2014 Elsevier B.V. All tights reserved.
    Journal of the Neurological Sciences 07/2014; 345(1-2). DOI:10.1016/j.jns.2014.07.022 · 2.26 Impact Factor
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    ABSTRACT: To determine the prognostic utility of tauopathy-associated single nucleotide polymorphisms (SNPs) in sporadic behavioral-variant frontotemporal dementia (bvFTD).METHODS: Eighty-one patients with sporadic bvFTD were genotyped for tauopathy-associated SNPs at rs8070723 (microtubule-associated protein tau [MAPT]) and rs1768208 (myelin-associated oligodendrocyte basic protein [MOBP]). We performed a retrospective case-control study comparing age at onset and disease duration between carriers of ≥1 polymorphism allele and noncarriers for these SNPs. Subanalyses were performed for autopsied subgroups with tauopathy (n = 20) and TDP-43 proteinopathy (n = 12). To identify a potential biological basis for disease duration, neuroimaging measures of white matter integrity were evaluated (n = 37).RESULTS: Carriers of risk allele (T) in rs1768208 (i.e., MOBP RA+) had a shorter median disease duration (TC/TT = 5.5 years, CC = 9.5 years; p = 0.02). This was also found in the subset of cases with autopsy-confirmed tauopathies (p = 0.04) but not with TDP-43 proteinopathies (p > 0.1). By comparison, polymorphisms at rs8070723 (MAPT) had no effect on disease duration (p > 0.1), although carriers of protective allele (G) in rs8070723 had a younger median age at onset (AG/GG = 54.5 years, AA = 58 years; p < 0.01). MOBP RA+ patients had increased radial diffusivity in the superior corona radiata and midbrain, and reduced fractional anisotropy in the superior corona radiata as well as superior and inferior longitudinal fasciculi compared with noncarriers (p < 0.01).CONCLUSIONS: The rs1768208 risk polymorphism in MOBP may have prognostic value in bvFTD. MOBP RA+ patients have more severe white matter degeneration in bvFTD that may contribute to shorter disease duration. Future studies are needed to help confirm these findings.
    Neurology 07/2014; 83(6). DOI:10.1212/WNL.0000000000000668 · 8.30 Impact Factor

Publication Stats

11k Citations
1,670.78 Total Impact Points


  • 1992–2015
    • University of Pennsylvania
      • • Department of Neurology
      • • Center for Neurodegenerative Disease Research
      Filadelfia, Pennsylvania, United States
  • 1995–2014
    • William Penn University
      Filadelfia, Pennsylvania, United States
  • 2013
    • Drexel University
      • Department of Neurology
      Philadelphia, PA, United States
  • 2011
    • Pennsylvania State University
      • Department of Neurology
      University Park, Maryland, United States
  • 1995–2011
    • Hospital of the University of Pennsylvania
      • Department of Neurology
      Philadelphia, Pennsylvania, United States
  • 2010
    • Drexel University College of Medicine
      • Department of Neurology
      Philadelphia, Pennsylvania, United States
    • University of Washington Seattle
      • Department of Medicine
      Seattle, Washington, United States
  • 2005–2008
    • Columbia University
      • • Department of Neurology
      • • Department of Psychology
      • • Department of Neuroscience
      New York City, New York, United States
  • 2007
    • Brandeis University
      • Volen Center for Complex Systems
      Waltham, Massachusetts, United States
    • Ludwig-Maximilians-University of Munich
      • Reference Center for Neurodegenerative Diseases
      München, Bavaria, Germany
    • Keimyung University
      Sŏul, Seoul, South Korea
  • 2006
    • Stratford University
      Stratford, Connecticut, United States
  • 2004
    • University of Michigan
      Ann Arbor, Michigan, United States
    • University of Cambridge
      Cambridge, England, United Kingdom
    • University of California, San Francisco
      • Department of Neurology
      San Francisco, CA, United States
  • 1998
    • Clark University
      • School of Psychology
      Worcester, Massachusetts, United States
  • 1987
    • Massachusetts Institute of Technology
      Cambridge, Massachusetts, United States