Semantic Memory Deficits Research Articles

Cognitive profile in cerebral small vessel disease: comparison between cerebral amyloid angiopathy and hypertension-related microangiopathy

Cerebral amyloid angiopathy (CAA) is recognized as a cause of cognitive impairment, but its cognitive profile needs to be characterized, also respect to hypertension-related microangiopathy (HA). We aimed at comparing difference or similarity of CAA and HA patients’ cognitive profiles, and their associated factors. Participants underwent an extensive clinical, neuropsychological, and neuroimaging protocol. HA patients (n = 39) were more frequently males, with history of vascular risk factors than CAA (n = 32). Compared to HA, CAA patients presented worse performance at MoCA (p = 0.001) and semantic fluency (p = 0.043), and a higher prevalence of amnestic MCI (46% vs. 68%). In univariate analyses, multi-domain MCI was associated with worse performance at MoCA, Rey Auditory Verbal Learning Test (RAVLT), and semantic fluency in CAA patients, and with worse performance at Symbol Digit Modalities Test (SDMT) and phonemic fluency in HA ones. In multivariate models, multi-domain deficit remained as the only factor associated with RAVLT (β = − 0.574) in CAA, while with SDMT (β = − 0.364) and phonemic fluency (β = − 0.351) in HA. Our results highlight different patterns of cognitive deficits in CAA or HA patients. While HA patients’ cognitive profile was confirmed as mainly attentional/executive, a complex cognitive profile, characterized also by deficit in semantic memory, seems the hallmark of CAA patients.

The neural substrates of transdiagnostic cognitive-linguistic heterogeneity in primary progressive aphasia

BackgroundClinical variants of primary progressive aphasia (PPA) are diagnosed based on characteristic patterns of language deficits, supported by corresponding neural changes on brain imaging. However, there is (i) considerable phenotypic variability within and between each diagnostic category with partially overlapping profiles of language performance between variants and (ii) accompanying non-linguistic cognitive impairments that may be independent of aphasia magnitude and disease severity. The neurobiological basis of this cognitive-linguistic heterogeneity remains unclear. Understanding the relationship between these variables would improve PPA clinical/research characterisation and strengthen clinical trial and symptomatic treatment design. We address these knowledge gaps using a data-driven transdiagnostic approach to chart cognitive-linguistic differences and their associations with grey/white matter degeneration across multiple PPA variants.MethodsForty-seven patients (13 semantic, 15 non-fluent, and 19 logopenic variant PPA) underwent assessment of general cognition, errors on language performance, and structural and diffusion magnetic resonance imaging to index whole-brain grey and white matter changes. Behavioural data were entered into varimax-rotated principal component analyses to derive orthogonal dimensions explaining the majority of cognitive variance. To uncover neural correlates of cognitive heterogeneity, derived components were used as covariates in neuroimaging analyses of grey matter (voxel-based morphometry) and white matter (network-based statistics of structural connectomes).ResultsFour behavioural components emerged: general cognition, semantic memory, working memory, and motor speech/phonology. Performance patterns on the latter three principal components were in keeping with each variant’s characteristic profile, but with a spectrum rather than categorical distribution across the cohort. General cognitive changes were most marked in logopenic variant PPA. Regardless of clinical diagnosis, general cognitive impairment was associated with inferior/posterior parietal grey/white matter involvement, semantic memory deficits with bilateral anterior temporal grey/white matter changes, working memory impairment with temporoparietal and frontostriatal grey/white matter involvement, and motor speech/phonology deficits with inferior/middle frontal grey matter alterations.ConclusionsCognitive-linguistic heterogeneity in PPA closely relates to individual-level variations on multiple behavioural dimensions and grey/white matter degeneration of regions within and beyond the language network. We further show that employment of transdiagnostic approaches may help to understand clinical symptom boundaries and reveal clinical and neural profiles that are shared across categorically defined variants of PPA.

21 Assessment of Semantic Memory Decline in aMCI : Naming and Semantic Knowledge of Unique and Non-Unique Entities

Objective:Semantic memory deficits have been reported in both Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI). However, the nature of this decline is still a matter of debate. The aim of this study was to explore the patterns of semantic memory impairment in aMCI by examining performance on naming tasks, and on tests assessing both general and specific semantic knowledge.Participants and Methods:Participants were divided in two groups matched for age and education, one comprising 33 aMCI individuals and the other 39 healthy controls. Three experimental tests assessing naming and semantic knowledge of unique items of famous persons (FACE) and places (PLACE), logos recognition (LOGO: brands and pictograms), and non-unique entities (Boston Naming Test: BNT) were administered, and the performance of the two groups was compared.Results:Lower scores were observed on all naming tests (PLACE, FACE, LOGO and BNT) in the aMCI group compared to controls. On the PLACE test, the general knowledge mean score (M=84.5, SD=12.9) was significantly higher than the specific knowledge mean score (M=54.2, SD=18.5) in aMCI participants (t(31)=11.9, p<.001), but not in controls (general: M=92.2, SD=11.1; specific: M=73.7, SD=15.8), and there was a significant Group X Type of knowledge interaction (F(1,1)=15.13, p <.001, n2 = 18). On the FACE test, in addition to significant group and condition (naming, semantic questions) main effects, a significant interaction was found (F(1,1)=7.19, p = .009, n2 = .09). On the LOGO task, controls were significantly better on brand items (M= 94.4, SD=10.5) than on pictograms (M=83.3, SD=12.2), while no significant difference was noted in aMCI (brands: M=81.5, SD=22.6; pictograms: M=77.5, SD=14.1). Lastly, on the BNT, aMCI participants benefited more from phonemic cues than controls (F(1,1)=16.56, p<.001, n2=19), suggesting a lexical access deficit, in addition to their semantic memory impairment.Conclusions:This study adds to the growing evidence confirming the presence of semantic memory deficits in aMCI. Specific semantic knowledge seems to be more affected than general semantic knowledge, a finding reported in previous studies. Lexical access deficits, in addition to semantic decline, were also observed in the aMCI group. These results allow for a better understanding of the pattern of semantic memory deficits in the prodromal stage of AD and could potentially facilitate diagnosis of aMCI.

Language profile of primary progressive aphasia in a linguistically diverse cohort in India

AbstractBackgroundThe accurate characterization of language and semantic memory deficits is crucial for diagnosis of primary progressive aphasia (PPA). In a linguistically diverse society like India, assessment with linguistically appropriate and culturally relevant tools is essential but challenging. This study aimed at developing language and culture specific tests to diagnose PPA and profile cognitive‐linguistic characteristics of a diverse cohort of PPA in India.MethodBased on typical characteristics of Indian languages: free‐word order, rich system of morphology and case‐marking that are features that differentiate Indian languages from English, a language‐specific assessment battery was developed in seven languages: Hindi, Bengali (Indo‐Aryan languages) and Kannada, Telugu, Malayalam and Tamil (Dravidian languages). In the background of the importance of case‐markers in the syntax of Indian languages, a unique syntax assessment test was specifically developed. To evaluate semantic memory, the Indian Semantic Memory battery was developed using stimuli appropriate for a pan‐Indian cultural context. All patients underwent assessment of language proficiency and comprehensive cognitive evaluation by examiners proficient in the language of testing.Result36 patients with PPA: 22 with semantic variant (svPPA), 12 nonfluent variant (nfvPPA) and 2 logopenic variant (lvPPA) participated. The cohort consisted of proficient speakers of seven Indian languages. A particular difficulty in the appropriate use of case markers on the new test of syntax was revealed in nfvPPA compared to svPPA. Further, the core diagnostic feature of ‘agrammatism’ for PPA in English‐speaking nfvPPA was not as dramatic in Indian patients owing to the morphological richness of Indian languages, leading to reduced contrast between fluent versus non‐fluent aphasia. Consistent with diagnosis, a significant reduction in fluency was demonstrated in nfvPPA (p< 0.006 on fluency tasks). Semantic memory was significantly affected in svPPA as revealed on non‐verbal tasks i.e., word‐picture matching (p<0.02)and semantic association task(p<0.01) of Indian Semantic Battery.ConclusionUsing language and culture specific assessment batteries tailored to the Indian context, a comprehensive clinical characteristics in PPA subtypes were identified. The need to re‐define agrammatism with respect to Indian languages with additional weightage to the use of case markers that assist in identifying the PPA subtype was a novel finding.

A category-selective semantic memory deficit for animate objects in semantic variant primary progressive aphasia.

Data are mixed on whether patients with semantic variant primary progressive aphasia exhibit a category-selective semantic deficit for animate objects. Moreover, there is little consensus regarding the neural substrates of this category-selective semantic deficit, though prior literature has suggested that the perirhinal cortex and the lateral posterior fusiform gyrus may support semantic memory functions important for processing animate objects. In this study, we investigated whether patients with semantic variant primary progressive aphasia exhibited a category-selective semantic deficit for animate objects in a word-picture matching task, controlling for psycholinguistic features of the stimuli, including frequency, familiarity, typicality and age of acquisition. We investigated the neural bases of this category selectivity by examining its relationship with cortical atrophy in two primary regions of interest: bilateral perirhinal cortex and lateral posterior fusiform gyri. We analysed data from 20 patients with semantic variant primary progressive aphasia (mean age = 64 years, S.D. = 6.94). For each participant, we calculated an animacy index score to denote the magnitude of the category-selective semantic deficit for animate objects. Multivariate regression analysis revealed a main effect of animacy (β = 0.52, t = 4.03, P < 0.001) even after including all psycholinguistic variables in the model, such that animate objects were less likely to be identified correctly relative to inanimate objects. Inspection of each individual patient’s data indicated the presence of a disproportionate impairment in animate objects in most patients. A linear regression analysis revealed a relationship between the right perirhinal cortex thickness and animacy index scores (β = −0.57, t = −2.74, P = 0.015) such that patients who were more disproportionally impaired for animate relative to inanimate objects exhibited thinner right perirhinal cortex. A vertex-wise general linear model analysis restricted to the temporal lobes revealed additional associations between positive animacy index scores (i.e. a disproportionately poorer performance on animate objects) and cortical atrophy in the right perirhinal and entorhinal cortex, superior, middle, and inferior temporal gyri, and the anterior fusiform gyrus, as well as the left anterior fusiform gyrus. Taken together, our results indicate that a category-selective semantic deficit for animate objects is a characteristic feature of semantic variant primary progressive aphasia that is detectable in most individuals. Our imaging findings provide further support for the role of the right perirhinal cortex and other temporal lobe regions in the semantic processing of animate objects.

Deficient semantic knowledge of the life course-Examining the cultural life script in Alzheimer's disease.

Cultural life scripts are culturally transmitted semantic knowledge of the expected order and timing of major transitional events in a prototypical life course. This cognitive schema has been shown to serve as an important mnemonic template that guides retrieval from autobiographical memory, especially for positive and important life events. Autobiographical memory deficits are one of the earliest and most prominent symptoms in Alzheimer's disease (AD). However, no studies have examined cultural life scripts in patients with AD, despite semantic memory impairments being reported even in the early stages of the disease. The aim of the present work was to assess life-script knowledge in older adults diagnosed with AD, particularly in terms of knowledge for the content of life-script events and the timing and temporal order of these events. Twenty-one older adults diagnosed with AD and 22 healthy age-matched controls completed the standard life-script task (Berntsen & Rubin, 2004, Memory & Cognition, 32[3], 427-442). We found that while AD patients produced significantly fewer life-script events, the content of the generated events were quite consistent with those of the controls and the cultural norms. AD patients were particular impaired with regard to the normative timing and order of life-script events, suggesting that these components of the cultural life script are more vulnerable to cognitive decline. The findings are discussed in relation to impaired script knowledge and semantic memory deficits in AD.

Semantic memory impairment in dementia: A cross-cultural adaptation study.

Semantic memory deficits are frequently encountered in dementia and distinct patterns of semantic impairment characterize the subtypes of dementia. Life course and cultural experiences significantly influence semantic memory. Hence, there is a need to assess semantic memory using culturally appropriate tests, to aid accurate diagnosis of dementia and facilitate cross-cultural collaborative research. In this prospective study, we adapted and validated the Cambridge Semantic Memory (CSM) test battery to the Indian cultural context and studied the patterns of semantic memory impairment across dementia subtypes. The CSM battery was modified using standard methods and by incorporating culturally appropriate changes and new semantic categories relevant to India. The adapted Indian Semantic Memory (ISM) test battery was administered to a cohort of 121 subjects, consisting of controls and dementia: Alzheimer's disease (AD), progressive non-fluent aphasia (PNFA), semantic dementia (SD), and behavioral variant fronto-temporal dementia (BvFTD). Profile of semantic memory performance across groups was examined. The ISM battery was found to be a valid measure of semantic memory. The novel semantic categories of gods/religious icons, vegetables, and food items added value to the diagnostic process. Distinct semantic memory profiles in SD, PNFA, AD, and BvFTD were demonstrated. The cultural adaptation of a semantic memory battery for the Indian context provided sensitive evidence of semantic memory impairment in dementia and its subtypes. The clinical and research application of the ISM battery will enhance diagnostic evaluation that can aid in early and accurate identification of deficits and devising intervention strategies and enable research across cultures.

In (deficit) schizophrenia, a general cognitive decline partly mediates the effects of neuro-immune and neuro-oxidative toxicity on the symptomatome and quality of life.

Schizophrenia and deficit schizophrenia are accompanied by neurocognitive impairments. The aim of this study was to examine whether a general factor underpins impairments in key Cambridge Neuropsychological Test Automated Battery (CANTAB) probes, verbal fluency test (VFT), world list memory (WLM), True Recall, and mini mental state examination (MMSE). We recruited 80 patients with schizophrenia and 40 healthy controls. All patients were assessed using CANTAB tests, namely paired-association learning, rapid visual information processing, spatial working memory, one touch stockings of Cambridge, intra/extradimensional set-shifting (IED), and emotional recognition test. We found that a general factor, which is essentially unidimensional, underlies those CANTAB, VFT, WLM, True Recall, and MMSE scores. This common factor shows excellent psychometric properties and fits a reflective model and, therefore, reflects a general cognitive decline (G-CoDe) comprising deficits in semantic and episodic memory, recall, executive functions, strategy use, rule acquisition, visual sustained attention, attentional set-shifting, and emotional recognition. Partial least squares analysis showed that 40.5% of the variance in G-CoDe is explained by C-C motif ligand 11, IgA to tryptophan catabolites, and increased oxidative toxicity, and that G-CoDe explains 44.8% of the variance in a general factor extracted from psychosis, hostility, excitation, mannerism, negative symptoms, formal thought disorders, and psychomotor retardation, and 40.9% in quality-of-life scores. The G-CoDe is significantly greater in deficit than in nondeficit schizophrenia. A common core shared by a multitude of neurocognitive impairments (G-CoDe) mediates the effects of neurotoxic pathways on the phenome of (deficit) schizophrenia.

Daily life activities in patients with Alzheimer’s disease or semantic dementia: Multitasking assessment

The aim of the present study was to compare patients with mild to moderate Alzheimer's disease (AD) or semantic dementia (SD) on their cognitive processes and the severity of their daily life activity impairments. Three types of tasks were administered to patients (SD = 15; AD = 31) and 30 healthy controls (HC): 1) informant-based scales and questionnaires, 2) a neuropsychological assessment exploring executive functions, episodic and semantic memory, and 3) a new original test featuring multi-step naturalistic actions and multitasking: the Sequential Daily Life Multitasking (SDLM). We predicted that patients with AD would mainly exhibit task perplexity, associated with episodic and executive deficits on the SDLM, while the behavior of patients with SD would mostly be characterized by object perplexity, associated with semantic memory deficits. Results showed that patients with AD or SD were impaired across all neuropsychological tests, particularly episodic memory in AD and semantic memory in SD. General performance on the SDLM also appeared dramatically impaired in both patient groups, and correlated with results of questionnaires about instrumental activities and memory impairments. However, specific qualitative measurements on the SDLM did not allow us to pinpoint different patterns of errors and behavior in patients with AD versus SD. We suggest that the inability of patients in both groups to perform the SDLM may derive from a constellation of disorders or else from more subtle impairment of cognitive and conative processes that requires further exploration.

Semantic and episodic memory performances of patients with Alzheimer’s disease and minor neurocognitive disorder

AbstractBackgroundModified Dead‐Alive Test (M‐DAT), which was developed and validated by Ozel‐Kizil et. al. (2018) evaluates semantic and episodic memory together. The original form was developed by Kapur et al. (1989), however it was not adequately studied.MethodM‐DAT consists of 45 names of celebrities who had died in remote past (15), died in the last five years (15) and who are still alive (15) and participants are asked whether they are alive or dead. Correct number of items concerning celebrities who died in remote past gives the semantic memory performance, while half of the the sum of correct number of items concerning celebrities who are still alive and had died in the last five years is accepted as episodic memory performance. Semantic and episodic memory performances of patients with DSM‐5 major neurocognitive disorder due to Alzheimer’s Disease‐MND‐AD (n=69), patients with DSM‐5 minor neurocognitive disorder‐MiND (n=27) who were admitted to geriatric psychiatry clinic and volunteered healthy controls‐HC (n=29) were compared. The groups were compared either by one‐way ANOVA or Kruskal‐Wallis tests and Bonferroni or Mann Whitney U tests was used for post‐hoc analysis.ResultMND‐AD group was older and less educated. Also MND‐AD group had lower MMSE scores while MiND and HCs had similar scores. MND‐AD had lower semantic and episodic scores than MiND and HC, also the scores of MiND group were lower than HCs. Both M‐DAT semantic and episodic scores were positively correlated with education in the whole sample (R=.53, p&lt;0.001; R=.43, p&lt;0.001). Although semantic memory performances were higher than episodic memory performances in all groups, two scores were positively correlated (R=.71, p&lt;0.001).ConclusionThe results of the study suggested a semantic memory impairment as well as episodic memory deficit in patients with major and minor neurocognitive disorder. Although previous studies have conflicting results, semantic memory deficit early in Alzheimer’s disease and in mild cognitive impairment was also reported (3). M‐DAT is an alternative for the assessment of semantic memory that is usually evaluated by verbal fluency tests. Evaluating episodic and semantic memory together is an important advantage however M‐DAT is affected by education and the items require updating.

Impaired integration of object feature knowledge in amnestic mild cognitive impairment.

Accessing semantic representations of real-world objects requires integration of multimodal perceptual features that are represented across relevant neocortical areas. Early Alzheimer's disease (AD) neuropathology, including neurofibrillary tangles in the perirhinal cortex as well as disrupted cortico-cortical connectivity, would be expected to disrupt the integration of object features. This integration deficit may underlie AD patients' semantic memory deficits and would be predicted to be more prominent for living objects, which tend to be more defined by sensory features compared with nonliving objects. Two experiments were conducted to assess feature integration in cognitively healthy older adults and patients with amnestic mild cognitive impairment (MCI). In both experiments, pictures of real-world objects were presented in congruent or incongruent colors. Participants were instructed to make a speeded color congruency judgment (Experiment 1) or name the presented surface color (Experiment 2). Across experiments, MCI patients showed a selective integration deficit for living, but not nonliving, objects across both experimental paradigms that was consistent with a deterioration in semantic structural representations rather than a deficit in controlled semantic retrieval. Planned secondary analyses with a subset of patients (Experiment 1) for whom PET imaging was available indicated that the degree of impairment was associated with the magnitude of cortical amyloid burden. These findings suggest that early AD pathology leads to impaired integration of distributed semantic object representations. The development of integration tasks as sensitive markers of early AD pathology may lead to more effective diagnostic tools for early detection and intervention. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

The association of memory disorders and chronic HIV disease in the antiretroviral therapy era: a systematic literature review.

Despite recent pharmacological progress, memory impairment is still frequently reported in people living with HIV. We aimed to conduct a systematic literature review investigating the presence of impairment of (sub)components of memory function in patients prescribed highly active antiretroviral therapy (ART). We adopted a cognitive neuropsychological model of memory function as the theoretical framework, distinguishing between a short-term working memory component and a long-term component of memory, along with their specific (sub)components. We systematically searched for the presence of impairment of each (sub)component in the selected papers. Careful consideration was given to study design and methods and control of covariates. Only the central executive component of working memory has been consistently reported to be impaired in HIV infection. The other two (sub)components, namely the phonological loop and the visuospatial sketchpad, were unimpaired. Discordant results have been obtained as to verbal and visual episodic memory, as some authors reported an association with HIV infection, whereas others did not. There is little evidence for semantic memory deficit in HIV infection, while there are suggestions that the neural substrate of implicit memory may be damaged by the effects of HIV infection and inflammation. Most studies in this area have been conducted in small samples and with poor control for covariates. Thus, conclusions regarding the association of memory dysfunction with HIV infection are hampered by methodological issues such as selection bias and unmeasured confounding. The task remains for future research to ascertain the impact of HIV infection on memory function.

Mathematics learning disabilities of the slow learner students on pythagorean theorem

This research was aimed to analyze mathematics learning disabilities of the slow learner on Pythagorean Theorem. This research was an exploratory study with qualitative approach. The subjects of this research were 2 of the 8th grade’s slow learner students of two inclusive schools in even semester of the 2017/2018 academic year. Data collection was done using test and interview method. Based on the data analysis, the results showed that the subjects had mathematics learning disabilities on Pythagorean Theorem that was categorized in (1) procedural memory deficit: the subject could not do the procedure properly and still had difficulty in operating the algebraic form, (2) semantic memory deficit: disability in learning arithmetic facts, disability in using the principle (3)visuospatial deficit: the subjects were still confused when the triangle was rotated.

Peripheral Blood Biomarkers Coupled with the Apolipoprotein E4 Genotype Are Strongly Associated with Semantic and Episodic Memory Impairments in Elderly Subjects with Amnestic Mild Cognitive Impairment and Alzheimer's Disease.

The Apolipoprotein E4 (ApoE4) genotype is strongly associated with Alzheimer's disease (AD), although the presence of the ApoE4 allele alone is not sufficient to explain AD. The pathophysiology of amnestic mild cognitive impairment (aMCI) remains unclear. This study aims to examine associations between peripheral blood biomarkers coupled with ApoE4 and episodic and semantic memory. The CERAD battery was completed and various biomarkers were assayed in 60 subjects with aMCI, 60 with AD, and 62 healthy controls. Deficits in semantic and episodic memory were significantly predicted by anion gap and bicarbonate, albumin, and glucose coupled with ApoE4. Furthermore, these peripheral biomarkers interacted with ApoE to predict greater memory impairments. Peripheral blood biomarkers may interact with pathways related to ApoE4 to predict greater semantic and episodic memory impairments, thus contributing to the pathophysiology of aMCI and AD. Our data suggest that the transition from aMCI to AD could at least in some cases be associated with significant interactions between ApoE4 and those peripheral blood biomarkers.

Dementia trajectory for patients with logopenic variant primary progressive aphasia.

The timing of progression of logopenic variant primary progressive aphasia (lvPPA) to severe dementia has not been elucidated. To address this shortcoming, 10 patients with lvPPA were continuously followed. Patients were assessed with the annual rate of change in the Clinical Dementia Rating (CDR) sum of boxes and period from lvPPA onset to the onset of benchmark signs, including mild, moderate, or severe dementia, episodic memory deficits, topographical disorientation, difficulties with using controls for electronic appliances, and conceptual apraxia. When severe dementia was evident, we also investigated the incidence of severe cognitive and behavioral signs such as neologistic jargon, difficulties in recognizing family members, pica, and mirror sign. The mean time for patients to reach a particular CDR was as follows: CDR of 1, 4.1 ± 1.3years post-onset; CDR 2, 5.7 ± 1.6years; CDR 3, 7.3 ± 1.6years. The annual rate of change in the CDR sum of boxes was 3.4 ± 1.1, corresponding to 1.7years for the CDR to increase by 1.0. Difficulties with using electronic controls began at 3.3 ± 1.6years, episodic memory deficits at 4.0 ± 2.0years, topographical disorientation at 5.2 ± 2.1years, and conceptual apraxia at 5.5 ± 2.1years. For patients who progressed to severe dementia, six could not recognize family members, five exhibited pica, three experienced mirror sign, and one developed neologistic jargon. Our results suggest that patients with lvPPA progress rapidly to dementia and develop conceptual apraxia, episodic memory deficits, visuospatial deficits, and semantic memory deficits.

Analysis of Verb Expressions in the Conversational Speech of Kannada-English Speaking Bilingual Persons with Mild

Dementia is characterized by the breakdown of intellectual and communicative functioning accompanied by personality change (DSM IV, American Psychiatric Association, 1994). Persons with dementia often experience difficulty in naming skills which can be attributed to semantic memory deficits. This can further influence various linguistic expressions such as lexical and morphological structures. The present study aimed to quantitatively and qualitatively analyze the presence of different types of verb inflections in bilingual (Kannada-English) persons with mild dementia. Considered for the study were 10 healthy elderly and 10 persons with mild dementia who were Kannada-English bilinguals. Spontaneous, conversational speech in all the participants was transcribed from which different types of verb inflexions in Kannada were extracted and analyzed. They included infinite verb, imperative verbs, negative imperatives, optative, and participle verbs. These were quantitatively and qualitatively analyzed for mean number of verbs and their nature including code mixing and switching identifying the significant differences between the two groups of participants. Results suggest that these measures offer a sensitive method for differentiating persons with mild dementia from healthy elderly. The study further helps in delineating prognostic indicator and planning rehabilitative measures which can be helpful tool for management.

NEUROPSYCHOLOGICAL PERFORMANCE DIFFERENCES BETWEEN TWO GROUPS OF PROBABLE-AD PATIENTS FROM DIFFERENT AREAS OF BRAZILNEUROPSYCHOLOGICAL PERFORMANCE DIFFERENCES BETWEEN TWO GROUPS OF PROBABLE-AD PATIENTS FROM DIFFERENT AREAS OF BRAZIL

During normal aging there are some cognitive and behavioral changes similar to those observed in a transitional state or mild cognitive impairment (MCI) and early onset dementia, making it challenging for health care professionals to reach an accurate and reliable diagnosis. Objective: The current study examined the performance of two different groups of patients diagnosed with probable Alzheimer’s disease (AD) on a neuropsychological test battery. Methods: Twenty-two AD patients from Brasília-DF (AD1) and thirty-four AD patients from Palmas-TO, northern Brazil (AD2), were selected and a short neuropsychological battery administered. To verify the reliability of these previous diagnoses of AD, both groups of patients were compared with a group of healthy controls. Results: AD patients showed cognitive deficit but scores were lower for the AD2 group compared with the AD1 group considering the cut-off point. Notably, patients from the AD1 group were older (p=0.004) and had less formal education (p&lt;0.001) than those from the AD2 group. Comparing different cognitive domains between AD groups, post hoc analysis showed that the AD1 group was characterized by deficits in episodic memory retrieval (p&lt;0.001), semantic memory (p&lt;0.001) and verbal fluency (p&lt;0.001). In contrast, the AD2 group showed lower scores in attention (p=0.007), executive functioning (p&lt;0.001) and working memory (p&lt;0.001). Conclusion: This pattern suggests that the Palma group of patients had a neuropsychological profile that was inconsistent with AD. Although the results of this study have important clinical implications, the effects of age, education, and gender on cognitive performance should be explored further.

Differential intrinsic functional connectivity changes in semantic variant primary progressive aphasia.

The semantic variant of primary progressive aphasia (svPPA) is a clinical syndrome characterized by semantic memory deficits with relatively preserved motor speech, syntax, and phonology. There is consistent evidence linking focal neurodegeneration of the anterior temporal lobes (ATL) to the semantic deficits observed in svPPA. Less is known about large-scale functional connectivity changes in this syndrome, particularly regarding the interplay between affected and spared language networks that leads to the unique cognitive dissociations typical of svPPA.Using whole-brain, seed-based connectivity on task-free Magnetic Resonance Imaging (MRI) data, we studied connectivity of networks anchored to three left-hemisphere regions crucially involved in svPPA symptomatology: ATL just posterior to the main atrophic area, opercular inferior frontal gyrus, and posterior inferior temporal lobe. First, in 32 healthy controls, these seeds isolated three networks: a ventral semantic network involving anterior middle temporal and angular gyri, a dorsal articulatory-phonological system involving inferior frontal and supramarginal regions, and a third functional connection between posterior inferior temporal and intraparietal regions likely involved in linking visual and linguistic processes. We then compared connectivity strength of these three networks between 16 svPPA patients and the 32 controls. In svPPA, decreased functional connectivity in the ventral semantic network correlated with weak semantic skills, while connectivity of the network seeded from the posterior inferior temporal lobe, though not significantly different between the two groups, correlated with pseudoword reading skills. Increased connectivity between the inferior frontal gyrus and the superior portion of the angular gyrus suggested possible adaptive changes.Our findings have two main implications. First, they support a functional subdivision of the left IPL based on its connectivity to specific language-related regions. Second, the unique neuroanatomical and linguistic profile observed in svPPA provides a compelling model for the functional interplay of these networks, being either up- or down- regulated in response to disease.

The investigation of semantic memory deficit in chronic tinnitus: a behavioral report

IntroductionTinnitus is a central auditory disorder in which different processing systems are involved as a network. One of these networks is memory. Previous studies have demonstrated some deficits in various types of memory in chronic tinnitus. ObjectivesThe main purpose of the present study was to investigate the semantic memory, which is not yet investigated in the tinnitus population. MethodsIn this case–control study, 15 subjects with chronic tinnitus and 16 matched healthy controls were included. 40 semantically related and 40 semantically unrelated word pairs were presented to the participants in a counter-balanced fashion. They were asked to make decision about their semantic relatedness. Then the participants’ reaction times and the accuracy of responses were calculated. ResultsMean of reaction times were significantly longer in the tinnitus group (M=1034ms, SD=0.31) compared to the control group (Mean=1016ms, SD=0.13), p<0.05. However, no significant difference was found for the mean percentage of correct responses between the two groups. ConclusionThe current study provided behavioral evidence that chronic tinnitus can affect the semantic memory. Such behavioral outcomes may provide new insights into more research activities in the field of electrophysiology and neuroimaging in the tinnitus population.

Pica

Pica is an extremely troublesome behaviors and causes a particularly high burdens for family caregivers. It can lead to dangerous medical consequences, such as malnutrition and intoxication, which sometimes require emergency medical treatment. Its neural basis and underlying mechanisms, however, have not been clarified. We addressed these issues by investigating patients with acquired brain injury who presented with pica. We found that semantic memory deficits were most often associated with pica rather than frontal release signs or changes in eating behaviors. Individuals with pica displayed lesion in the posterior part of the middle temporal gyrus, although spread across a wide area. Taken together, our findings suggest that semantic memory deficits, because of temporal lobe damage might be associated with pica. Moreover, Alzheimer's disease and semantic dementia are the two main degenerative disease etiologies that cause pica. Our findings may also be applied to degenerative disorders as temporal lobe involvement and semantic memory deficits are common. The most common items ingested in pica are daily necessities that are easy to swallow or drink; as such, these items should be avoided in patients with pica.