A case of semantic variant primary progressive aphasia with Pick’s pathology

Neurodegenerative diseases are caused by aggregation of specific proteins that catalyze a cascade of changes that ultimately lead to neurodegeneration. This concept guides current diagnostic approaches, as well as clinical trials, that focus on detecting or removing amyloid or tau from the brain. The semantic variant of primary progressive aphasia (svPPA), a clinical syndrome associated with frontotemporal lobar degeneration (FTLD) pathology, is usually associated with the molecular pathology TDP-C, but there are cases with TDP-B and Pick’s disease. The existing literature on the clinical differentiation of these pathologies is limited. Here, we present a case study, in conjunction with a cross-sectional voxel-based morphometry (VBM), to elucidate the clinical and imaging features of a patient with svPPA due to Pick’s disease.     

Semantic dementia and primary progressive aphasia: a problem of categorization?

The relationship between semantic dementia (SD) and primary progressive aphasia (PPA) has been the subject of debate ever since the syndromes were first described, in converging streams of research from the neuropsychological and neurologic communities. The most salient clinical features of SD are anomia with circumlocution and semantic paraphasia, single-word comprehension deficit, and reduced category fluency. Of critical importance is the fact that patients also show deficits on non-verbal tasks using visual, auditory, and other modalities, suggesting that the key impairment in SD is a breakdown in conceptual knowledge rather than a specific problem with language. The finding of item consistency between the various tests supports this view. The order in which the features appear can be explained by the variable degree of redundancy in access to semantic knowledge from the different perceptual modalities. Atrophy is seen in the anterior and inferior temporal lobe rather than in classic language areas, further distancing SD from aphasic syndromes. Semantic dementia and progressive non-fluent aphasia (PNFA) share some clinical and pathologic characteristics with frontal variant frontotemporal dementia, but there are also clear differences between the three syndromes. We believe that many patients described as having fluent primary progressive aphasia in fact have early SD. Semantic dementia is a well-defined syndrome, distinct from PNFA but related to it within the spectrum of frontotemporal lobar degeneration syndromes.     

Single‐word semantic judgements in semantic dementia: Do phonology and grammatical class count?

Background: Listeners make active use of phonological regularities such as word length to facilitate higher‐level syntactic and semantic processing. For example, nouns are longer than verbs, and abstract words are longer than concrete words. Patients with semantic dementia (SD) experience conceptual loss with preserved syntax and phonology. The extent to which patients with SD exploit phonological regularities to support language processing remains unclear.

Aims: We examined the ability of patients with SD (1) to perceive subtle acoustic–phonetic distinctions in English, and (2) to bootstrap their accuracy of lexical‐semantic and syntactic judgements from regularities in the phonological forms of English nouns and verbs.

Methods and Procedures: Four patients with SD made minimal pair judgements (same/different) for auditorily presented stimuli selectively varied by voice, place, or manner of the initial consonant (e.g., pa –ba). In Experiment 2 patients made forced‐choice semantic judgements (abstract or concrete) for single words varied by (1) concreteness (abstract or concrete); (2) grammatical class (noun or verb); and (3) word length (one‐ or three‐syllable words).

Outcomes and Results: The most semantically impaired patients paradoxically showed the highest accuracy of minimal pair phonologic discrimination. Judgements of word concreteness were less accurate for verbs than nouns. Among verbs, accuracy was worse for concrete than abstract items (e.g., eat was worse than think). Patients were more likely to misclassify longer concrete words (e.g., professor) as abstract, demonstrating sensitivity to an underlying phonologically mediated semantic property in English.

Conclusions: Single‐word semantic judgements were sensitive to both grammatical class and phonological properties of the words being evaluated. Theoretical and clinical implications are addressed in the context of an anatomically constrained model of SD that assumes increasing reliance on phonology as lexical‐semantic knowledge degrades.     

Therapy of short‐term memory disorders in fluent aphasia: A single case study

Background: Repetition conduction aphasia is defined as a phonological short‐term memory (STM) deficit. The interactive activation model of verbal STM proposed by N. Martin and Saffran (1992 Martin, N. and Saffran, E. M. 1992. A computational account of deep dysphasia.. Brain and Language, 43: 240–274. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) accounts for this deficit by an increased activation decay rate. Recently Majerus and van der Linden (2001 Majerus, S. and Van der Linden, M. 2001. “Les relations entre compréhension verbale et mémoire de travail.”. In Actualités en pathologie du langage et de la communication, Edited by: Aubin, G, Belin, C and David, D. 189–214. Marseille, France: Solal.  [Google Scholar]) suggested that these short‐term memory impairments could be improved by therapy.

Aims: The purpose of our single case study was to investigate whether the temporary storage of verbal information could be improved by therapy in a patient with repetition conduction aphasia.

Methods & Procedures: A patient suffering from a fluent aphasia was trained over 31 therapy sessions. In the therapy task he had to repeat sentences of four to seven words with an increasing delay between stimulus and response. The control task consisted of repeating sentences of four to six words without delay.

Outcomes & Results: The treatment improved sentence repetition significantly. In addition, sentence length in oral production and spans for digits and bisyllabic words, i.e., measures for phonological STM, improved.

Conclusions: Verbal STM performances were improved through therapy. It is argued that in the light of N. Martin and Saffran's theory, these improvements reflect a partially normalised activation decay, although the role of a probably very mild reduction of connection strength remains unclear.     

Vascular dementia and Alzheimer's disease: is there a difference? A comparison of symptoms by disease duration

This study examined differences between vascular dementia (VaD) by the NINDS/AIRENS criteria and Alzheimer's disease (AD) on clinical grounds. A consecutive series of 517 patients with probable and possible VaD or AD were evaluated for cognitive, functional, and behavioral symptoms and separated into three subgroups by duration of dementia. These AD and VaD subgroups were then compared on a series of standardized clinical measures. The only consistent trends were for VaD patients to be more depressed, more functionally impaired, and less cognitively impaired within each disease duration subgroup. The authors conclude that there are few differences between clinically diagnosed VaD and AD. Subclassification of VaD into subgroups will improve the clinical utility of this nosologic entity.     

A review of lexical retrieval intervention in primary progressive aphasia and Alzheimer’s disease: mechanisms of change,generalisation, and cognition

Background: While significant benefits of lexical retrieval intervention are evident within the primary progressive aphasia (PPA) and Alzheimer’s disease (AD) literature, an understanding of the mechanisms that underlie change is limited. Change mechanisms have been explored in the post-stroke aphasia literature and offer insight into how change occurs through interventions with progressive language disorders. Exploration of change mechanisms may progress our understanding as to how and why generalisation is likely, or not, to occur, as well as gain insight into the non-linguistic cognitive functions that may play a role.

Aims: This review of the literature aimed to (1) map the mechanisms of change that have been proposed or hypothesised within the PPA and AD lexical retrieval intervention literature to a theoretical framework based on a framework of motor recovery following stroke and accounts of change mechanisms within the post-stroke aphasia literature and explore whether particular mechanisms of change were associated with more effective outcomes; (2) determine whether particular mechanisms of change were associated with within- and across-level linguistic generalisation, and (3) investigate the role of non-linguistic cognitive functions in the lexical retrieval intervention studies reviewed here.

Main Contribution: A search of Medline, PsycINFO, and CINAHL identified 37 papers published between 1982 and April 2016 that reported lexical retrieval intervention in people with PPA or AD, categorised here according to whether the proposed change mechanism was stimulation (12 studies), relearning (21 studies), reorganisation (three studies), or cognitive-relay (two studies). Significant treatment gains, predominantly based on linguistic performance measures, were reported for both diagnostic groups in association with the proposed mechanisms of stimulation and relearning. Significant treatment gains were also reported for people with PPA in association with reorganisation and cognitive-relay mechanisms; these mechanisms were only employed in PPA studies. Varying outcomes for linguistic generalisation were reported in 26 PPA and six AD studies. Nineteen studies incorporated non-linguistic cognitive functions in intervention; these were limited to autobiographical memory (17 studies), episodic memory (three studies), or both (one study).

Conclusion: This review highlights that individuals with PPA and AD benefit from lexical retrieval intervention, irrespective of the mechanism of change, and that linguistic generalisation was reported in studies proposing different change mechanisms. Insufficient exploration of the role of non-linguistic cognitive functions was highlighted with respect to assessment, planning intervention, and interpreting intervention outcomes. Recommendations are made, with a view to heightening our ability to interpret intervention outcomes.     

Argyrophilic thorny astrocyte clusters in association with Alzheimer’s disease pathology in possible primary progressive aphasia

Although most cases of primary progressive aphasia (PPA) have one of the varieties of frontotemporal lobar degeneration (FTLD) as their pathological substrate, a subset shows Alzheimer’s disease (AD) pathology. We report that all eight cases in our clinic diagnosed as possible PPA, on account of the presence of episodic memory difficulties in addition to severe language impairment at the onset of disease, showed AD pathology. Neither focal accentuation of AD pathology nor vascular lesions in language-related areas was observed. Seven of these eight patients showed large argyrophilic thorny astrocyte clusters (ATAC) in the fronto-temporo-parietal cortex and subcortical white matter. The intensely tau immunoreactive astrocytes in ATAC were morphologically similar to the perivascular, subpial, and subependymal astrocytes in elderly brains, but ATAC differ from the latter by the cortical and subcortical location, widespread distribution outside the medial temporal lobe, and intense argyrophilia. The location of ATAC was related to neither local variations in the load of AD pathology, nor the myelin density of white matter. ATAC were not seen in a comparison group of six cases of AD without a prominent aphasia syndrome. Because of the similarity of astrocytes in ATAC to those seen independently of AD pathology in several subtypes of FTLD and two reported cases of PPA we hypothesize that they are a marker of a pathological process concurrent with AD, and related to the focality of the clinical presentation.     

Fluctuating cognition and different cognitive and behavioural profiles in Parkinson’s disease with dementia: comparison of dementia with Lewy bodies and Alzheimer’s disease

To examine the occurrence of fluctuating cognition (FC) in a group of patients with Parkinson’s disease with dementia (PDD), and to determine whether the presence of FC in PDD is associated with a pattern of cognitive and behavioural disturbances similar to the one shown by patients affected by dementia with Lewy bodies (DLB), a cluster analysis was carried out on the scores obtained by 27 PDD patients on the Clinician Assessment of Fluctuation Scale (CAF). The analysis separated the PDD patients into two subgroups, called PDD non-fluctuators (PDDNF; CAF ≤ 2) and PDD fluctuators (PDDF; CAF > 2). The two groups underwent a cognitive and behavioural evaluation. Their scores were compared with those obtained by DLB and Alzheimer’s disease (AD) patients. When exploring the cognitive performance of the patients with the Dementia Rating Scale-2 (DRS-2), PDDF had a similar pattern of impairments compared to DLB, which involved prevalently the attention and initiation/perseveration domains, and which was significantly more pronounced compared to that shown by PDDNF. The main behavioural finding of the study was the similar incidence of visual hallucinations in the PDDF and DLB groups, which was significantly higher compared to PDDNF and AD. Our results confirmed the hypothesis that subgroups with different cognitive profiles exist within PDD and that the occurrence of FC is the clinical variable associated with a DLB pattern of impairment in PDD. In conclusion, our study suggests that when FC occurs in PDD this syndrome becomes clinically undistinguishable from DLB.     

Evaluation of plasma Aβ as predictor of Alzheimer's disease in older individuals without dementia: a population-based study

Amyloid-β (Aβ) pathology is a major component in the mechanisms behind Alzheimer's disease (AD). Measurement of Aβ(42) in cerebrospinal fluid predicts cognitive decline in patients with mild cognitive impairment and identifies AD in patients with dementia. However, studies on Aβ in plasma are contradictory. In this prospective population-based study, plasma Aβ(42) and Aβ(40) were measured at baseline in 730 adults aged 70 years or older and without dementia. After five years, plasma levels were analyzed again and participants were assessed for development of dementia. During follow-up, 53 individuals (7%) developed dementia of which 37 (5%) were classified as AD. No difference in baseline plasma Aβ(42), Aβ(40), or Aβ(42)/Aβ(40) ratio levels were observed between converters to dementia or AD compared to the cognitively stable individuals. However, individuals with plasma Aβ(40) levels above the median level for the group at baseline had an increased risk of developing dementia and AD during the follow-up, even after adjustment for age, gender, APOE genotype, and educational level (odds ratio = 2.2, 95% confidence interval = 1.0-4.7, p < 0.05). Neither plasma Aβ(42) nor the Aβ(42)/Aβ(40) ratio influenced the risk of developing dementia or AD. Moreover, Aβ(42) and Aβ(40) levels increased over the 5 years, whereas the Aβ(42)/Aβ(40) ratio decreased (p < 0.001). In conclusion, this study suggests that measurement of plasma Aβ should not be used clinically to predict dementia or AD. However, plasma Aβ(40) may possibly be regarded as a moderate risk marker comparable to other risk markers for AD such as first-degree family history of dementia.     

The processing of compounds in bilingual aphasia: A multiple‐case study

Background: While converging evidence has led to the view that people with aphasia exploit compositional procedures when producing compound words, the issue of what compound‐internal characteristics are at play during these procedures is still under debate. It has been argued that constituent position and/or morphosyntactic prominence, i.e., being the head constituent of a compound, may influence the manner in which compounds are accessed. However, findings obtained from patient performances are thus far inconclusive, because positional and headedness effects are frequently confounded in a language.

Aims: In order to disentangle position‐in‐the‐string and headedness effects in compound production in aphasia, the main objective of this study is to investigate the performance of bilingual patients speaking languages in which these effects can be teased apart. Our secondary goal is to probe the roles of grammatical category (adjectives vs nouns) and of between‐language phonological similarity, as both these factors have been demonstrated to influence compound processing.

Methods & Procedures: Three English–French bilingual persons with aphasia participated in the study. Three experimental tasks, reading, repetition, and translation of isolated compound words, were administrated in each language. We contrasted French and English compounds that differ in the position of the head constituent: left for French and right for English.

Outcomes & Results: Two participants showed a similar pattern—a significantly reduced number of errors for the head (or first) constituent as compared to the non‐head (or second) constituent in French and an equivalent number of errors for both constituents in English—pointing to the cumulative effects of headedness and first‐position‐in‐the‐string in French, and to the mutual cancelling out of these effects in English. The third participant exhibited a non‐head constituent advantage in both languages, indicating that semantic modification of the head constituent by the non‐head constituent plays a prominent role in her accessing procedures. For all three participants phonological similarity influenced production, while grammatical category did not.

Conclusions: Our results reveal that headedness and position interact in the processing of compounds. They also demonstrate that compound constituents are processed asymmetrically across and within languages, thus confirming that people with aphasia are sensitive to compound‐internal structure. Moreover, they show that patients rely on varying structural information when accessing compounds.     

Is a plum a memory problem? Longitudinal study of the reversal of concreteness effect in a patient with semantic dementia

The concreteness effect, which refers to the typically superior performance for concrete concepts compared to abstract ones, is a robust phenomenon that has been observed in normal and brain-damaged subjects in a number of cognitive domains. Reversal of this effect was also reported in a few neuropsychological studies, mainly in patients with semantic dementia (SD). In this article, we report the first longitudinal single-case study of a patient with SD, SC, who performed better for abstract than concrete concepts in various comprehension and production tasks. For concrete concepts, SC showed no category-specific deficit but was impaired in tasks exploring access to stored structural knowledge and semantic perceptual attributes. With the course of the disease, the semantic system progressively declined and the reversal of the concreteness effect, as well as the dissociation between perceptual and non-perceptual knowledge, vanished. We discuss the results and their implications for theoretical propositions of concreteness effect as well as theoretical models of semantic memory. We suggest that the reversal of concreteness in SC is a direct result of the degradation of visual feature knowledge, sustained by anatomical structures affected early in SD. With the time course of the disease, the atrophy extends to adjacent regions and the dissociation between abstract and concrete concepts was no longer observed.     

The patterns of progression in primary progressive aphasia—Implications for assessment and management

Background: Primary progressive aphasia (PPA) is a progressive language disorder with preserved cognitive function for at least 2 years from onset. The main variants currently distinguished are: non-fluent/agrammatic (nfvPPA), semantic (svPPA), and logopenic (lvPPA). Patients with initial language presentation may subsequently develop other symptoms, such as behavioural dysfunction or apraxia. The clinical pattern of PPA depends on the location of atrophy, the underlying pathology, and the stage of the disease.

Aims: This review aims at characterising longitudinal changes in clinical presentations of different PPA variants and at presenting implications of these changes for the assessment, diagnosis, and management.

Main contribution: The three PPA variants differ not only in terms of language impairment, but also with regard to cognitive and behavioural profile. Apraxia and rigidity frequently occur in the course of nfvPPA. Patients with lvPPA seem to follow the pattern of aphasic Alzheimer’s disease, where language impairment is accompanied by episodic memory deficit. Individuals diagnosed with svPPA often develop behavioural dysfunction similar to that observed in behavioural variant of frontotemporal dementia.

Conclusions: Implications for patient care are dependent on PPA variant and on the stage of the disease. In svPPA, emphasis should be on the management of semantic and behavioural problems in daily life. Caregivers of nfvPPA patients should be informed about the possible emergence of apraxia and other movement disorders. In contrast, families of individuals with lvPPA should be made aware of and trained to cope with an episodic memory decline and possible progression to other varieties of PPA.     

Rethinking the dementia diagnoses in a population-based study: what is Alzheimer's disease and what is vascular dementia?. A study from the kungsholmen project

OBJECTIVE: To explore the hypothesis that older adults often are affected by more than one disease, making the differential diagnosis between Alzheimer's disease (AD) and vascular dementia (VaD) difficult. METHODS: Incident dementia cases (n = 308) from a population-based longitudinal study of people 75+ years were investigated. The DSM-III-R criteria were used for the clinical diagnosis of dementia. Data on vascular disorders (hypertension, cerebrovascular and ischemic heart diseases, heart failure, atrial fibrillation, diabetes) as well as type of onset/course of dementia were used retrospectively to reclassify dementias. RESULTS: Only 47% of the AD cases were reclassified as pure AD without any vascular disorder. Among subjects with AD and with a vascular component, cerebrovascular disease was the most common (41%). Only 25% of VaD were reclassified as pure VaD. Further, 26% of the pure AD subjects developed a vascular disorder in the following 3 years. CONCLUSIONS: Both vascular and degenerative mechanisms may often contribute to the expression of dementia among the elderly. Most of the AD cases have vascular involvements, and pure dementia types in very old subjects constitute only a minority of dementia cases.     

Known,lost, and recovered: Efficacy of formal‐semantic therapy and spaced retrieval method in a case of semantic dementia

Background: Few studies have addressed rehabilitation in semantic dementia. A potentially promising method is formal‐semantic therapy, which consists of tasks in which the names of concepts and their semantic characteristics are presented. It could also be enhanced by spaced retrieval, a learning method improving retention through recalling information after increasing recall intervals.

Aims: This study explores the efficacy of both a formal‐semantic therapy and the spaced retrieval method to restore lost concepts in TBo, a woman with semantic dementia.

Methods & Procedures: The formal‐semantic therapy consisted of giving TBo semantic feedback followed by a cueing technique to facilitate naming. Formal‐semantic therapy with simple repetition was compared to formal‐semantic therapy with spaced retrieval. TBo's performance was measured throughout the study with picture naming and generation of verbal attributes. Two untrained lists were also measured for generalisation effects.

Outcomes & Results: Results indicate that, after therapy, TBo could name 3/8 of the trained items, compared to no items on the untrained lists. She also showed an increase in performance for the evocation of specific semantic attributes of concepts, reaching 6/8 of correct responses. Moreover, she maintained her performance up to 5 weeks after the end of the study. Finally, when compared to simple repeated practice, spaced retrieval did not enhance learning and no generalisation was observed between trained and non‐trained categories.

Conclusions: Along with recent results reported in the literature, TBo's results confirm that people with semantic dementia can improve their naming performance with training but that this is limited. However, formal‐semantic therapy seems very promising for retraining specific semantic attributes. Instead of focusing on naming, we suggest that therapies used in semantic dementia should aim at restoring specific and functionally relevant concepts to enable the individuals to be more autonomous in daily living.     

Immediate and short‐term effects of contextual priming on word retrieval in aphasia

Background: Many therapy techniques for word retrieval disorders use some form of priming to improve access to words. Priming can facilitate or interfere with naming under different circumstances. We examined effects of priming when combined with semantic or phonological context (training words in groups that are semantically or phonologically related) and how these effects interact with the type of naming impairment (semantically or phonologically based). Aims: We addressed three questions (1) Are word retrieval impairments differentially sensitive to priming with semantic or phonological contexts? (2) Would such differences be systematically related to deficits of semantic versus phonological processing? (3) Do effects of priming evolve from immediate interference to short‐term facilitation, as predicted by an interactive activation model of word retrieval? Methods & Procedures: A total of 11 chronic English‐speaking aphasic subjects with varied types of aphasia participated in this experiment. Background measures of semantic and phonological processing ability were administered to determine the nature of each subject's naming impairment. The experiment involved one‐session facilitation treatments for each of three context conditions (semantic, phonological, and unrelated), plus three replications (nine subjects) or one replication (two subjects). Ten pictures in each condition were tested before and after treatment. Five pictures were trained and five served as controls. Participants repeated the name of each picture four times (repetition priming) and then attempted to name each picture individually (naming probe). Repetition priming and naming probes were repeated eight times. We used McNemar tests to compare rates of correct responses before and after priming, and chi square analyses of correct responses and contextual errors on naming probes obtained during the priming sessions. Outcome & results: Our predictions were borne out in the data. Participants varied in their sensitivity to the semantic and phonological contexts. The error data suggest that interference during training is more likely when the context (semantic or phonological) and underlying source of the word processing impairment (semantic or phonological) match. Additionally, we found two sequential effects of contextual priming: immediate interference followed short‐term facilitation. Conclusions: These data have theoretical implications regarding the time course of priming effects, but also have important clinical implications. The present contextual priming procedure is relatively short and could be used as a predictor of performance patterns in a long‐term treatment protocol that uses this approach or other tasks that employ priming.     

A quantitative study of α-synuclein pathology in fifteen cases of dementia associated with Parkinson disease

The α-synuclein-immunoreactive pathology of dementia associated with Parkinson disease (DPD) comprises Lewy bodies (LB), Lewy neurites (LN), and Lewy grains (LG). The densities of LB, LN, LG together with vacuoles, neurons, abnormally enlarged neurons (EN), and glial cell nuclei were measured in fifteen cases of DPD. Densities of LN and LG were up to 19 and 70 times those of LB, respectively, depending on region. Densities were significantly greater in amygdala, entorhinal cortex (EC), and sectors CA2/CA3 of the hippocampus, whereas middle frontal gyrus, sector CA1, and dentate gyrus were least affected. Low densities of vacuoles and EN were recorded in most regions. There were differences in the numerical density of neurons between regions, but no statistical difference between patients and controls. In the cortex, the density of LB and vacuoles was similar in upper and lower laminae, while the densities of LN and LG were greater in upper cortex. The densities of LB, LN, and LG were positively correlated. Principal components analysis suggested that DPD cases were heterogeneous with pathology primarily affecting either hippocampus or cortex. The data suggest in DPD: (1) ratio of LN and LG to LB varies between regions, (2) low densities of vacuoles and EN are present in most brain regions, (3) degeneration occurs across cortical laminae, upper laminae being particularly affected, (4) LB, LN and LG may represent degeneration of the same neurons, and (5) disease heterogeneity may result from variation in anatomical pathway affected by cell-to-cell transfer of α-synuclein.     

CSF amyloid-β peptides in neuropathologically diagnosed dementia with Lewy bodies and Alzheimer's disease

Appropriate treatment of dementia requires biomarkers that provide an exact and differential diagnosis. We recently presented differentially expressed amyloid-β (Aβ) peptide patterns in cerebrospinal fluid (CSF) as biomarker candidates for neurochemical diagnosis of Alzheimer's disease (AD) and dementia with Lewy bodies (DLB). The objective of the present study was to investigate CSF Aβ peptide patterns in both neuropathologically and clinically defined diagnostic groups of AD and DLB. Using the quantitative Aβ-SDS-PAGE/immunoblot, we analyzed CSF samples of neuropathologically defined patients with AD (definite AD, dAD; n = 11) and DLB (definite, dDLB; n = 12). We compared absolute and relative quantities of CSF Aβ-peptides with a larger cohort of clinically diagnosed patients with probable AD (pAD; n = 71), probable DLB (pDLB; n = 32), and non-demented controls (NDC; n = 71). Each neuropathologically and clinically defined diagnostic group showed a similar relative distribution of CSF Aβ-peptides (Aβ(1-X%)). Aβ(1-42%) was lowered in dAD compared to NDC (p = 1.6 × 10??, but did not differ between dAD and pAD. Aβ(1-40ox%) was elevated in dDLB as compared to NDC (p = 1.8 × 10??, but did not differ between dDLB and pDLB. Thus, we were able to confirm previous results on Aβ peptide patterns in neuropathologically characterized patients with AD and DLB. Our results underline the usefulness of the CSF Aβ(1-42%) and Aβ(1-40ox%) as diagnostic biomarkers for AD and DLB, respectively.