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1.  Seizures and Epileptiform Activity in the Early Stages of Alzheimer Disease 
JAMA neurology  2013;70(9):1158-1166.
IMPORTANCE
Epileptic activity associated with Alzheimer disease (AD) deserves increased attention because it has a harmful impact on these patients, can easily go unrecognized and untreated, and may reflect pathogenic processes that also contribute to other aspects of the illness. We report key features of AD-related seizures and epileptiform activity that are instructive for clinical practice and highlight similarities between AD and transgenic animal models of the disease.
OBJECTIVE
To describe common clinical characteristics and treatment outcomes of patients with amnestic mild cognitive impairment (aMCI) or early AD who also have epilepsy or subclinical epileptiform activity.
DESIGN
Retrospective observational study from 2007 to 2012.
SETTING
Memory and Aging Center, University of California, San Francisco.
PATIENTS
We studied 54 patients with a diagnosis of aMCI plus epilepsy (n = 12), AD plus epilepsy (n = 35), and AD plus subclinical epileptiform activity (n = 7).
MAIN OUTCOMES AND MEASURES
Clinical and demographic data, electroencephalogram (EEG) readings, and treatment responses to antiepileptic medications.
RESULTS
Patients with aMCI who had epilepsy presented with symptoms of cognitive decline 6.8 years earlier than patients with aMCI who did not have epilepsy (64.3 vs 71.1 years; P = .02). Patients with AD who had epilepsy presented with cognitive decline 5.5 years earlier than patients with AD who did not have epilepsy (64.8 vs 70.3 years; P = .001). Patients with AD who had subclinical epileptiform activity also had an early onset of cognitive decline (58.9 years). The timing of seizure onset in patients with aMCI and AD was nonuniform (P < .001), clustering near the onset of cognitive decline. Epilepsies were most often complex partial seizures (47%) and more than half were nonconvulsive (55%). Serial or extended EEG monitoring appeared to be more effective than routine EEG at detecting interictal and subclinical epileptiform activity. Epileptic foci were predominantly unilateral and temporal. Of the most commonly prescribed antiepileptics, treatment outcomes appeared to be better for lamotrigine and levetiracetam than for phenytoin.
CONCLUSIONS AND RELEVANCE
Common clinical features of patients with aMCI- or AD-associated epilepsy at our center included early age at onset of cognitive decline, early incidence of seizures in the disease course, unilateral temporal epileptic foci detected by serial/extended EEG, transient cognitive dysfunction, and good seizure control and tolerability with lamotrigine and levetiracetam. Careful identification and treatment of epilepsy in such patients may improve their clinical course.
doi:10.1001/jamaneurol.2013.136
PMCID: PMC4013391  PMID: 23835471
2.  Treatment for lexical retrieval in progressive aphasia 
Aphasiology  2008;22(7-8):826-838.
Background
Treatment for lexical retrieval impairment has been shown to yield positive outcomes in individuals with aphasia due to focal lesions, but there has been little research regarding the treatment of such impairments in individuals with progressive aphasia.
Aims
The purpose of this study was to examine the therapeutic effects of a semantic treatment for anomia in progressive aphasia relative to the outcome in an individual with stroke-induced aphasia.
Methods & Procedures
Two individuals with progressive aphasia and one with aphasia resulting from stroke participated in the study. Each participant presented with fluent, anomic aphasia; however, one of the patients with progressive aphasia demonstrated characteristics indicating a likely progression towards non-fluency. Each participant received a brief, intensive treatment intended to improve lexical retrieval in the context of generative naming for selected semantic categories. Treatment tasks included guided lexical retrieval prompted by the identification and elaboration of items within semantic subcategories, as well as other semantic tasks. Treatment outcomes were quantified using standard effects sizes as well as nonparametric tests comparing pre- versus post-treatment performance.
Outcomes & Results
One of the individuals with progressive aphasia showed large treatment effects for lexical retrieval of items from targeted semantic categories. The other progressive aphasia patient showed very small effects overall for treated categories. The individual with the focal lesion due to stroke showed medium-sized effects for trained categories as well as significant improvement on a standardised measure of naming.
Conclusions
Findings indicate that intensive, semantically based treatment for lexical retrieval can result in positive outcomes in individuals with progressive as well as stroke-induced aphasia. Examination of individual differences suggests that the status of semantic and episodic memory may provide predictive information regarding responsiveness to treatment.
doi:10.1080/02687030701820055
PMCID: PMC2942781  PMID: 20862210
Progressive aphasia; Treatment; Rehabilitation; Anomia; Lexical retrieval
3.  Treatment for Anomia in Semantic Dementia 
Anomia is a striking and consistent clinical feature of semantic dementia (SD), a progressive aphasia syndrome associated with focal cortical atrophy of the anterior temporal lobes. Word retrieval deficits in patients with SD have been attributed to the loss of conceptual knowledge, resulting in an impairment referred to as semantic anomia. Whereas an abundance of research has been dedicated to treatment for anomia in individuals with focal brain damage due to stroke, considerably less work has been done regarding treatment for patients with progressive language decline. The purpose of this article is to review the available literature concerning the nature and treatment of anomia in individuals with SD. Several studies have shown that new lexical learning remains possible in these patients. However, newly learned information is likely to be constrained by the learning context, and increased reliance on perceptual and autobiographical contextual information may be necessary to provide critical support for new vocabulary acquisition. There is also evidence suggesting that treatment may slow the progression of anomia over time, even affording some protective benefit to lexical items that are not yet lost. However, treatment efforts are likely to be most beneficial at early stages of the disease, when residual semantic knowledge as. well as relatively spared episodic memory may support new learning.
doi:10.1055/s-2008-1061625
PMCID: PMC2699352  PMID: 18348092
Naming; rehabilitation; lexical retrieval; memory; primary progressive aphasia
4.  Elicitation of specific syntactic structures in primary progressive aphasia 
Brain and language  2012;123(3):183-190.
Many patients with primary progressive aphasia (PPA) are impaired in syntactic production. Because most previous studies of expressive syntax in PPA have relied on quantitative analysis of connected speech samples, which is a relatively unconstrained task, it is not well understood which specific syntactic structures are most challenging for these patients. We used an elicited syntactic production task to identify which syntactic structures pose difficulties for 31 patients with three variants of PPA: non-fluent/agrammatic, semantic and logopenic. Neurodegenerative and healthy age-matched participants were included as controls. As expected, non-fluent/agrammatic patients made the most syntactic errors. The structures that resulted in the most errors were constructions involving third person singular present agreement, and constructions involving embedded clauses. Deficits on this elicited production task were associated with atrophy of the left posterior inferior frontal gyrus.
doi:10.1016/j.bandl.2012.09.004
PMCID: PMC3502680  PMID: 23046707
syntax; production; primary progressive aphasia; voxel-based morphometry
5.  Syntactic processing depends on dorsal language tracts 
Neuron  2011;72(2):397-403.
Frontal and temporal language areas involved in syntactic processing are connected by several dorsal and ventral tracts, but the functional roles of the different tracts are not well understood. To identify which white matter tract(s) are important for syntactic processing, we examined the relationship between white matter damage and syntactic deficits in patients with primary progressive aphasia, using multimodal neuroimaging and neurolinguistic assessment. Diffusion tensor imaging showed that microstructural damage to left hemisphere dorsal tracts—the superior longitudinal fasciculus including its arcuate component—was strongly associated with deficits in comprehension and production of syntax. Damage to these dorsal tracts predicted syntactic deficits after gray matter atrophy was taken into account, and fMRI confirmed that these tracts connect regions modulated by syntactic processing. In contrast, damage to ventral tracts—the extreme capsule fiber system or the uncinate fasciculus—was not associated with syntactic deficits. Our findings show that syntactic processing depends primarily on dorsal language tracts.
doi:10.1016/j.neuron.2011.09.014
PMCID: PMC3201770  PMID: 22017996
6.  White matter damage in primary progressive aphasias: a diffusion tensor tractography study 
Brain  2011;134(10):3011-3029.
Primary progressive aphasia is a clinical syndrome that encompasses three major phenotypes: non-fluent/agrammatic, semantic and logopenic. These clinical entities have been associated with characteristic patterns of focal grey matter atrophy in left posterior frontoinsular, anterior temporal and left temporoparietal regions, respectively. Recently, network-level dysfunction has been hypothesized but research to date has focused largely on studying grey matter damage. The aim of this study was to assess the integrity of white matter tracts in the different primary progressive aphasia subtypes. We used diffusion tensor imaging in 48 individuals: nine non-fluent, nine semantic, nine logopenic and 21 age-matched controls. Probabilistic tractography was used to identify bilateral inferior longitudinal (anterior, middle, posterior) and uncinate fasciculi (referred to as the ventral pathway); and the superior longitudinal fasciculus segmented into its frontosupramarginal, frontoangular, frontotemporal and temporoparietal components, (referred to as the dorsal pathway). We compared the tracts’ mean fractional anisotropy, axial, radial and mean diffusivities for each tract in the different diagnostic categories. The most prominent white matter changes were found in the dorsal pathways in non-fluent patients, in the two ventral pathways and the temporal components of the dorsal pathways in semantic variant, and in the temporoparietal component of the dorsal bundles in logopenic patients. Each of the primary progressive aphasia variants showed different patterns of diffusion tensor metrics alterations: non-fluent patients showed the greatest changes in fractional anisotropy and radial and mean diffusivities; semantic variant patients had severe changes in all metrics; and logopenic patients had the least white matter damage, mainly involving diffusivity, with fractional anisotropy altered only in the temporoparietal component of the dorsal pathway. This study demonstrates that both careful dissection of the main language tracts and consideration of all diffusion tensor metrics are necessary to characterize the white matter changes that occur in the variants of primary progressive aphasia. These results highlight the potential value of diffusion tensor imaging as a new tool in the multimodal diagnostic evaluation of primary progressive aphasia.
doi:10.1093/brain/awr099
PMCID: PMC3187537  PMID: 21666264
primary progressive aphasia; progressive non-fluent aphasia; semantic dementia; logopenic progressive aphasia; diffusion tensor imaging
7.  Written language impairments in primary progressive aphasia: A reflection of damage to central semantic and phonological processes 
Journal of Cognitive Neuroscience  2011;24(2):261-275.
Connectionist theories of language propose that written language deficits arise as a result of damage to semantic and phonological systems that also support spoken language production and comprehension, a view referred to as the “primary systems” hypothesis. The objective of the current study was to evaluate the primary systems account in a mixed group of individuals with primary progressive aphasia (PPA) by investigating the relation between measures of non-orthographic semantic and phonological processing and written language performance, and by examining whether common patterns of cortical atrophy underlie impairments in spoken versus written language domains. Individuals with PPA and healthy controls were administered a language battery including assessments of semantics, phonology, reading, and spelling. Voxel-based morphometry was used to examine the relation between gray matter volumes and language measures within brain regions previously implicated in semantic and phonological processing. In accordance with the primary systems account, our findings indicate that spoken language performance is strongly predictive of reading/spelling profile in individuals with PPA and suggest that common networks of critical left hemisphere regions support central semantic and phonological processes recruited for spoken and written language.
doi:10.1162/jocn_a_00153
PMCID: PMC3307525  PMID: 22004048
8.  Connected speech production in three variants of primary progressive aphasia 
Brain  2010;133(7):2069-2088.
Primary progressive aphasia is a clinical syndrome defined by progressive deficits isolated to speech and/or language, and can be classified into non-fluent, semantic and logopenic variants based on motor speech, linguistic and cognitive features. The connected speech of patients with primary progressive aphasia has often been dichotomized simply as ‘fluent’ or ‘non-fluent’, however fluency is a multidimensional construct that encompasses features such as speech rate, phrase length, articulatory agility and syntactic structure, which are not always impacted in parallel. In this study, our first objective was to improve the characterization of connected speech production in each variant of primary progressive aphasia, by quantifying speech output along a number of motor speech and linguistic dimensions simultaneously. Secondly, we aimed to determine the neuroanatomical correlates of changes along these different dimensions. We recorded, transcribed and analysed speech samples for 50 patients with primary progressive aphasia, along with neurodegenerative and normal control groups. Patients were scanned with magnetic resonance imaging, and voxel-based morphometry was used to identify regions where atrophy correlated significantly with motor speech and linguistic features. Speech samples in patients with the non-fluent variant were characterized by slow rate, distortions, syntactic errors and reduced complexity. In contrast, patients with the semantic variant exhibited normal rate and very few speech or syntactic errors, but showed increased proportions of closed class words, pronouns and verbs, and higher frequency nouns, reflecting lexical retrieval deficits. In patients with the logopenic variant, speech rate (a common proxy for fluency) was intermediate between the other two variants, but distortions and syntactic errors were less common than in the non-fluent variant, while lexical access was less impaired than in the semantic variant. Reduced speech rate was linked with atrophy to a wide range of both anterior and posterior language regions, but specific deficits had more circumscribed anatomical correlates. Frontal regions were associated with motor speech and syntactic processes, anterior and inferior temporal regions with lexical retrieval, and posterior temporal regions with phonological errors and several other types of disruptions to fluency. These findings demonstrate that a multidimensional quantification of connected speech production is necessary to characterize the differences between the speech patterns of each primary progressive aphasic variant adequately, and to reveal associations between particular aspects of connected speech and specific components of the neural network for speech production.
doi:10.1093/brain/awq129
PMCID: PMC2892940  PMID: 20542982
primary progressive aphasia; progressive non-fluent aphasia; semantic dementia; logopenic progressive aphasia; speech production
9.  Neural correlates of syntactic processing in the non-fluent variant of primary progressive aphasia 
The left posterior inferior frontal cortex (IFC) is important for syntactic processing, and has been shown in many functional imaging studies to be differentially recruited for the processing of syntactically complex sentences relative to simpler ones. In the non-fluent variant of primary progressive aphasia (PPA), degeneration of the posterior IFC is associated with expressive and receptive agrammatism, however the functional status of this region in non-fluent PPA is not well understood. Our objective was to determine whether the atrophic posterior IFC is differentially recruited for the processing of syntactically complex sentences in non-fluent PPA. Using structural and functional magnetic resonance imaging, we quantified tissue volumes and functional responses to a syntactic comprehension task in eight patients with non-fluent PPA, compared to healthy age-matched controls. In controls, the posterior IFC showed more activity for syntactically complex sentences than simpler ones, as expected. In non-fluent PPA patients, the posterior IFC was atrophic and, unlike controls, showed an equivalent level of functional activity for syntactically complex and simpler sentences. This abnormal pattern of functional activity was specific to the posterior IFC: the mid superior temporal sulcus, another region modulated by syntactic complexity in controls, showed normal modulation by complexity in patients. A more anterior inferior frontal region was recruited by patients, but did not support successful syntactic processing. We conclude that in non-fluent PPA, the posterior IFC is not only structurally damaged, but is also functionally abnormal, suggesting a critical role for this region in the breakdown of syntactic processing in this syndrome.
doi:10.1523/JNEUROSCI.2547-10.2010
PMCID: PMC3024013  PMID: 21159955
syntactic processing; primary progressive aphasia; progressive non-fluent aphasia; inferior frontal gyrus; superior temporal sulcus; functional magnetic resonance imaging
10.  Phonological Dyslexia and Dysgraphia: Cognitive Mechanisms and Neural Substrates 
To examine the validity of different theoretical assumptions about the neuropsychological mechanisms and lesion correlates of phonological dyslexia and dysgraphia, we studied written and spoken language performance in a large cohort of patients with focal damage to perisylvian cortical regions implicated in phonological processing. Despite considerable variation in accuracy for both words and non-words, the majority of participants demonstrated the increased lexicality effects in reading and spelling that are considered the hallmark features of phonological dyslexia and dysgraphia. Increased lexicality effects were also documented in spoken language tasks such as oral repetition, and patients performed poorly on a battery of phonological tests that did not involve an orthographic component. Furthermore, a composite measure of general phonological ability was strongly predictive of both reading and spelling accuracy, and we obtained evidence that the continuum of severity that characterized the written language disorder of our patients was attributable to an underlying continuum of phonological impairment. Although patients demonstrated qualitatively similar deficits across measures of written and spoken language processing, there were quantitative differences in levels of performance reflecting task difficulty effects. Spelling was more severely affected than reading by the reduction in phonological capacity and this differential vulnerability accounted for occasional disparities between patterns of impairment on the two written language tasks. Our findings suggest that phonological dyslexia and dysgraphia in patients with perisylvian lesions are manifestations of a central or modality-independent phonological deficit rather than the result of damage to cognitive components dedicated to reading or spelling. Our results also provide empirical support for shared-components models of written language processing, according to which the same central cognitive systems support both reading and spelling. Lesion-deficit correlations indicated that phonological dyslexia and dysgraphia may be produced by damage to a variety of perisylvian cortical regions, consistent with distributed network models of phonological processing.
doi:10.1016/j.cortex.2008.04.006
PMCID: PMC2689874  PMID: 18625494
phonological dyslexia/dysgraphia; perisylvian cortex; phonological deficit
11.  Do Dual-Route Models Accurately Predict Reading and Spelling Performance in Individuals with Acquired Alexia and Agraphia? 
Neuropsychologia  2007;45(11):2519-2524.
Coltheart and colleagues (Coltheart, Rastle, Perry, Langdon, & Ziegler, 2001; Castles, Bates, & Coltheart, 2006) have demonstrated that an equation derived from dual-route theory accurately predicts reading performance in young normal readers and in children with reading impairment due to developmental dyslexia or stroke. In this paper we present evidence that the dual-route equation and a related multiple regression model also accurately predict both reading and spelling performance in adult neurological patients with acquired alexia and agraphia. These findings provide empirical support for dual-route theories of written language processing.
doi:10.1016/j.neuropsychologia.2007.03.019
PMCID: PMC1988783  PMID: 17482218
dual-route theory; reading; spelling; alexia; agraphia
12.  The role of left perisylvian cortical regions in spelling ☆ 
Brain and language  2006;100(1):44-52.
In order to examine the role of left perisylvian cortex in spelling, 13 individuals with lesions in this area were administered a comprehensive spelling battery. Their spelling of regular words, irregular words, and nonwords was compared with that of individuals with extrasylvian damage involving left inferior temporo–occipital cortex and normal controls. Perisylvian patients demonstrated a lexicality effect, with nonwords spelled worse than real words. This pattern contrasts with the deficit in irregular word spelling, or regularity effect, observed in extrasylvian patients. These findings confirm that damage to left perisylvian cortex results in impaired phonological processing required for sublexical spelling. Further, degraded phonological input to orthographic selection typically results in additional deficits in real word spelling.
doi:10.1016/j.bandl.2006.06.011
PMCID: PMC2362101  PMID: 16890279
Phonological agraphia; Aphasia; Perisylvian cortex; Lexical agraphia; Spelling; Writing; Phonological processing
13.  Positive Effects of Language Treatment for the Logopenic Variant of Primary Progressive Aphasia 
Despite considerable recent progress in understanding the underlying neurobiology of primary progressive aphasia (PPA) syndromes, relatively little attention has been directed toward the examination of behavioral interventions that may lessen the pervasive communication problems associated with PPA. In this study, we report on an individual with a behavioral profile and cortical atrophy pattern consistent with the logopenic variant of PPA. At roughly two-and-a-half years post onset, his marked lexical retrieval impairment prompted administration of a semantically based intervention to improve word retrieval. The treatment was designed to improve self-directed efforts to engage the participant’s relatively preserved semantic system in order to facilitate word retrieval. His positive response to an intensive (2-week) dose of behavioral treatment was associated with improved lexical retrieval of items within trained categories, and generalized improvement for naming of untrained items that lasted over a 6-month follow-up interval. These findings support the potential value of intensive training to achieve self-directed strategic compensation for lexical retrieval difficulties in logopenic PPA. Additional insight was gained regarding the neural regions that supported improved performance by the administration of a functional magnetic resonance imaging protocol before and after treatment. In the context of a picture-naming task, post-treatment fMRI showed increased activation of left dorsolateral prefrontal regions that have been implicated in functional imaging studies of generative naming in healthy individuals. The increased activation in these frontal regions that were not significantly atrophic in our patient (as determined by voxel-based morphometry) is consistent with the notion that neural plasticity can support compensation for specific language loss, even in the context of progressive neuronal degeneration.
doi:10.1007/s12031-011-9579-2
PMCID: PMC3208072  PMID: 21710364
PPA; Rehabilitation; Anomia; Lexical retrieval; fMRI; Voxel-based morphometry

Results 1-13 (13)