Confrontation naming impairment in dementia

Semantic Priming from Uncued Distractors in Alzheimer's Disease

RESEARCH QUESTION

Are semantic impairments in Alzheimer's disease (AD) partially due to deficits in spatial attention?

METHODS AND RESULTS

In a target detection task, both older adults (OAs) and AD individuals were facilitated by valid spatial cues, but only OAs were impaired by invalid cues compared to neutral. In a reading task, spatial cues validly or invalidly cued the location of pictures, which were related or unrelated to subsequent, centrally presented, words. OAs showed semantic priming only after valid cues, whereas AD individuals showed priming after valid and invalid cues.

DISCUSSION

Failure to inhibit uncued locations results in processing of potentially distracting semantic information in AD.

Neuropsychological differential diagnosis of Alzheimer's disease and vascular dementia: a systematic review with meta-regressions

Introduction

Diagnostic classification systems and guidelines posit distinguishing patterns of impairment in Alzheimer's (AD) and vascular dementia (VaD). In our study, we aim to identify which diagnostic instruments distinguish them.

Methods

We searched PubMed and PsychInfo for empirical studies published until December 2020, which investigated differences in cognitive, behavioral, psychiatric, and functional measures in patients older than 64 years and reported information on VaD subtype, age, education, dementia severity, and proportion of women. We systematically reviewed these studies and conducted Bayesian hierarchical meta-regressions to quantify the evidence for differences using the Bayes factor (BF). The risk of bias was assessed using the Newcastle-Ottawa-Scale and funnel plots.

Results

We identified 122 studies with 17,850 AD and 5,247 VaD patients. Methodological limitations of the included studies are low comparability of patient groups and an untransparent patient selection process. In the digit span backward task, AD patients were nine times more probable (BF = 9.38) to outperform VaD patients (β g = 0.33, 95% ETI = 0.12, 0.52). In the phonemic fluency task, AD patients outperformed subcortical VaD (sVaD) patients (β g = 0.51, 95% ETI = 0.22, 0.77, BF = 42.36). VaD patients, in contrast, outperformed AD patients in verbal (β g = -0.61, 95% ETI = -0.97, -0.26, BF = 22.71) and visual (β g = -0.85, 95% ETI = -1.29, -0.32, BF = 13.67) delayed recall. We found the greatest difference in verbal memory, showing that sVaD patients outperform AD patients (β g = -0.64, 95% ETI = -0.88, -0.36, BF = 72.97). Finally, AD patients performed worse than sVaD patients in recognition memory tasks (β g = -0.76, 95% ETI = -1.26, -0.26, BF = 11.50).

Conclusion

Our findings show inferior performance of AD in episodic memory and superior performance in working memory. We found little support for other differences proposed by diagnostic systems and diagnostic guidelines. The utility of cognitive, behavioral, psychiatric, and functional measures in differential diagnosis is limited and should be complemented by other information. Finally, we identify research areas and avenues, which could significantly improve the diagnostic value of cognitive measures.

Argentinean Psycholinguistic Picture Naming Test in color

Color has demonstrated to have an influence on picture naming tasks. Objects with high color diagnosticity are recalled faster than objects with low value. That is why the Argentinean Psycholinguistic Picture Naming Test in color (PAPDIC in Spanish) was designed. The items and semantic cues were built considering local psycholinguistic norms. A series of psychometric analyses were performed on a sample of patients with focal brain damage with (n = 11) and without (n = 14) aphasia, a sample of patients with degenerative disease (n = 46) and two samples of healthy participants (young n = 27, old n = 50). Evidence of convergent validity was obtained through the correlation with the brief Boston Naming Test (r = 0.871; p < .001); of criteria validity by means of contrasted groups analysis (t = 4.059, p < .001), and through the ROC curve analysis (AUC = 0.993). Scores' reliability was explored by means of an internal consistency analysis (KR20 = 0.905). These results indicate that the PAPDIC is a promising color naming test which can be applied in the field of clinical neuropsychology to identify anomia. This test has several advantages in comparison with the available naming tests in Argentina.

Picture-naming test for a linguistically diverse population with cognitive impairment and dementia

BACKGROUND

Picture-naming tests (PNTs) evaluate linguistic impairment in dementia due to semantic memory impairment, impaired lexical retrieval or perceptual deficits. They also assess the decline in naming impairment at various stages of dementia and mild cognitive impairment (MCI) that occurs due to progressive cognitive impairment. With the increasing numbers of people with dementia globally, it is necessary to have validated naming tests and norms that are culturally and linguistically appropriate.

AIMS

In this cross-sectional study we harmonized a set of 30 images applicable to the Indian context across five languages and investigated the picture-naming performance in patients with MCI and dementia.

METHODS & PROCEDURES

A multidisciplinary expert group formed by the Indian Council of Medical Research (ICMR) collaborated towards developing and adapting a picture naming test (PNT) known as the ICMR-PNT in five Indian languages: Hindi, Bengali, Telugu, Kannada and Malayalam. Based on cross-cultural adaptation guidelines and item-wise factor analysis and correlations established separately across five languages, the final version of the ICMR-PNT test was developed. A total of 368 controls, 123 dementia and 128 MCI patients were recruited for the study. Psychometric properties of the adapted version of the ICMR-PNT were examined, and sensitivity and specificity were examined.

OUTCOMES & RESULTS

The ICMR-PNT scores in all languages combined were higher in controls compared with patients with dementia and MCI (F_{2, 615} = 139.85; p < 0.001). Furthermore, PNT scores for MCI was higher in comparison with patients with dementia in all languages combined (p < 0.001). The area under the curve across the five languages ranged from 0.81 to 1.00 for detecting dementia. There was a negative correlation between Clinical Dementia Rating (CDR) and ICMR-PNT scores and a positive correlation between Addenbrooke's Cognitive Examination-III (ACE-III) and ICMR-PNT scores in control and patient groups.

CONCLUSIONS & IMPLICATIONS

The ICMR-PNT was developed by following cross-cultural adaptation guidelines and establishing correlations using item-wise factor analysis across five languages. This adapted PNT was found to be a reliable tool when assessing naming abilities effectively in mild to moderate dementia in a linguistically diverse context.

WHAT THIS PAPER ADDS

What is already known on this subject Picture-naming evaluates language impairment linked to naming difficulties due to semantic memory, lexical retrieval or perceptual disturbances. As a result, picture naming tests (PNTs) play an important role in the diagnosis of dementia. In a heterogeneous population such as India, there is a need for a common PNT that can be used across the wide range of languages. What this study adds to existing knowledge PNTs such as the Boston Naming Test (BNT) were developed for the educated, mostly English-speaking, Western populations and are not appropriate for use in an Indian context. To overcome this challenge, a PNT was harmonized in five Indian languages (Hindi, Bengali, Telugu, Kannada and Malayalam) and we report the patterns of naming difficulty in patients with MCI and dementia. The ICMR-PNT demonstrated good diagnostic accuracy when distinguishing patients with mild to moderate dementia from cognitively normal individuals. What are the potential or actual clinical implications of this work? With the growing number of persons suffering from Alzheimer's disease and other forms of dementia around the world, its critical to have culturally and linguistically relevant naming tests and diagnosis. This validated ICMR-PNT can be used widely as a clinical tool to diagnose dementia and harmonize research efforts across diverse populations.

Learning From Mistakes: Cognitive and Metabolic Correlates of Errors on Picture Naming in the Alzheimer’s Disease Spectrum

Background: Analysis of subtypes of picture naming errors produced by patients with Alzheimer’s disease (AD) have seldom been investigated yet may clarify the cognitive and neural underpinnings of naming in the AD spectrum. Objective: To elucidate the neurocognitive bases of picture naming in AD through a qualitative analysis of errors. Methods: Over 1000 naming errors produced by 70 patients with amnestic, visuospatial, linguistic, or frontal AD were correlated with general cognitive tests and with distribution of hypometabolism on FDG-PET. Results: Principal component analysis identified 1) a Visual processing factor clustering visuospatial tests and unrecognized stimuli, pure visual errors and visual-semantic errors, associated with right parieto-occipital hypometabolism; 2) a Concept-Lemma factor grouping language tests and anomias, circumlocutions, superordinates, and coordinates, correlated with left basal temporal hypometabolism; 3) a Lemma-Phonology factor including the digit span and phonological errors, linked with left temporo-parietal hypometabolism. Regression of brain metabolism on individual errors showed that errors due to impairment of basic and higher-order processing of object visual attributes or of their interaction with semantics, were related with bilateral occipital and left occipito-temporal dysfunction. Omissions and superordinates were linked to degradation of broad and basic concepts in the left basal temporal cortex. Semantic-lexical errors derived from faulty semantically- and phonologically-driven lexical retrieval in the left superior and middle temporal gyri. Generation of nonwords was underpinned by of phonological impairment within the left inferior parietal cortex. Conclusion: Analysis of individual naming errors allowed to outline a comprehensive anatomo-functional model of picture naming in classical and atypical AD.

Knowledge Representations Derived From Semantic Fluency Data

The semantic fluency task is commonly used as a measure of one’s ability to retrieve semantic concepts. While performance is typically scored by counting the total number of responses, the ordering of responses can be used to estimate how individuals or groups organize semantic concepts within a category. I provide an overview of this methodology, using Alzheimer’s disease as a case study for how the approach can help advance theoretical questions about the nature of semantic representation. However, many open questions surrounding the validity and reliability of this approach remain unresolved.

Cerebral perfusion mediated by thalamo-cortical functional connectivity in non-dominant thalamus affects naming ability in aphasia

Naming is a commonly impaired language domain in various types of aphasia. Emerging evidence supports the cortico‐subcortical circuitry subserving naming processing, although neurovascular regulation of the non‐dominant thalamic and basal ganglia subregions underlying post‐stroke naming difficulty remains unclear. Data from 25 subacute stroke patients and 26 age‐, sex‐, and education‐matched healthy volunteers were analyzed. Region‐of‐interest‐wise functional connectivity (FC) was calculated to measure the strength of cortico‐subcortical connections. Cerebral blood flow (CBF) was determined to reflect perfusion levels. Correlation and mediation analyses were performed to identify the relationship between cortico‐subcortical connectivity, regional cerebral perfusion, and naming performance. We observed increased right‐hemispheric subcortical connectivity in patients. FC between the right posterior superior temporal sulcus (pSTS) and lateral/medial prefrontal thalamus (lPFtha/mPFtha) exhibited significantly negative correlations with total naming score. Trend‐level increased CBF in subcortical nuclei, including that in the right lPFtha, and significant negative correlations between naming and regional perfusion of the right lPFtha were observed. The relationship between CBF in the right lPFtha and naming was fully mediated by the lPFtha‐pSTS connectivity in the non‐dominant hemisphere. Our findings suggest that perfusion changes in the right thalamic subregions affect naming performance through thalamo‐cortical circuits in post‐stroke aphasia. This study highlights the neurovascular pathophysiology of the non‐dominant hemisphere and demonstrates thalamic involvement in naming after stroke.

fMRI Investigation of Semantic Lexical Processing in Healthy Control and Alzheimer's Disease Subjects Using Naming Task: A Preliminary Study

For decades, scientists have been trying to solve the problem of dementia, with no cure currently available. Semantic-lexical impairment is well established as the early critical sign of dementia, although there are still gaps in knowledge that must be investigated. In this study, we used fMRI to observe the neural activity of 31 subjects, including 16 HC (Healthy Control) and 15 AD (Alzheimer's Disease), who participated in the naming task. The neuropsychology profile of HC (Healthy Control) and AD (Alzheimer's Disease) are discussed in this study. The involvement of FG (Fusiform Gyrus) and IFG (Inferior Frontal Gyrus) shows dominant activation in both of the groups. We observed a decrease in neural activity in the AD group, resulting in semantic deficit problems in this preliminary study. Furthermore, ROI analysis was performed and revealed both hyperactivation and hypoactivation in the AD group. The compensatory mechanism demonstrated during the task, due to the effort required to identify an animal's name, represents the character profile of AD.

Episodic memory decline is associated with deficits in coherence of discourse

This study investigates coherence of discourse in the production of autobiographical narratives by individuals with aMCI. Autobiographical interviews were analyzed to determine whether reduced episodic recall was related to deficits in discourse coherence. A coherence rating scale was used to evaluate relatedness of the autobiographical details produced by participants to the topic of discourse. Interviews were transcribed, segmented into details, and divided into sets of episodic, semantic, or supplementary information, which were subsequently analysed with the coherence rating scale. We predicted that the known episodic deficits observed in aMCI could also affect the retrieval of coherent episodic information. The results revealed deficits in coherence could be found in both episodic and semantic information in the aMCI group. These results suggest that the cognitive deficits experienced by individuals with aMCI may go beyond their known difficulty in recalling episodic details, as they also affect the controlled retrieval of both episodic and semantic information.

A Metabolic Imaging Study of Lexical and Phonological Naming Errors in Alzheimer Disease

Patients with Alzheimer disease (AD) produce a variety of errors on confrontation naming that indicate multiple loci of impairment along the naming process in this disease. We correlated brain hypometabolism, measured with 18fluoro-deoxy-glucose positron emission tomography, with semantic and formal errors, as well as nonwords deriving from phonological errors produced in a picture-naming test by 63 patients with AD. Findings suggest that neurodegeneration leads to: (1) phonemic errors, by interfering with phonological short-term memory, or with control over retrieval of phonological or prearticulatory representations, within the left supramarginal gyrus; (2) semantic errors, by disrupting general semantic or visual-semantic representations at the level of the left posterior middle and inferior occipitotemporal cortex, respectively; (3) formal errors, by damaging the lexical-phonological output interface in the left mid-anterior segment of middle and superior temporal gyri. This topography of semantic-lexical-phonological steps of naming is in substantial agreement with dual-stream neurocognitive models of word generation.

Connected Speech Features from Picture Description in Alzheimer's Disease: A Systematic Review

The language changes that occur over the course of Alzheimer's disease (AD) can impact communication abilities and have profound functional consequences. Picture description tasks can be used to approximate everyday communication abilities of AD patients. As various methods and variables have been studied over the years, current knowledge about the most affected features of AD discourse in the context of picture descriptions is difficult to summarize. This systematic review aims to provide researchers with an overview of the most common areas of impairment in AD discourse as they appear in picture description tasks. Based on the 44 articles fulfilling inclusion criteria, our findings reflect a multidimensional pattern of changes in the production (speech rate), syntactic (length of utterance), lexical (word-frequency and use of pronouns), fluency (repetitions and word-finding difficulties), semantic (information units), and discourse (efficiency) domains. We discuss our findings in the light of current research and point to potential scientific and clinical uses of picture description tasks in the context of AD.

Validation of the Thai version of the short Boston Naming Test (T-BNT) in patients with Alzheimer's dementia and mild cognitive impairment: clinical and biomarker correlates

OBJECTIVES

Impairments in the Boston Naming Test (BNT), which measures confrontational word retrieval, frequently accompanies Alzheimer's dementia (AD) and may predict a more rapid progression of illness. This study aims to validate the Thai version of the 15-item BNT (T-BNT) in participants with AD and amnestic mild cognitive impairment (aMCI) and to externally validate the T-BNT using clinical and biomarker measurements.

METHODS

This cross-sectional study recruited patients with AD, diagnosed according to NINCDS-ADRDA criteria (n = 60), aMCI, diagnosed using the Petersen criteria (n = 60), and healthy controls (n = 62). We examined the internal consistency, concurrent and discriminant reliability of the T-BNT. We also assessed the Mini Mental State Examination (MMSE), the Verbal Fluency Test (VFT) and the Word List Memory (WLM) tests and measured apolipoprotein E polymorphism and serum levels of folic acid, high-density lipoprotein cholesterol (HDL) and triglycerides.

RESULTS

This study validated a 10-item T-BNT (10T-BNT), which yielded good internal consistency (0.92), a one-factor unidimensional structure, and adequate concurrent and discriminant validity. Lower scores on the 10T-BNT highly significantly predict AD, but not aMCI, and are positively associated with VFT and WLM test scores. Furthermore, lowered 10T-BNT scores are significantly associated with the ApoE4 allele, lower folate levels and an increased triglyceride/HDL-cholesterol ratio.

CONCLUSIONS

This study validated the 10T-BNT and the total score on this scale is strongly associated with AD, impairments in semantic and episodic memory and biomarkers, which are known to modify memory via different mechanisms.

Benefit of phonemic cueing on confrontation naming in Alzheimer's disease

Objective: Deficits in confrontation naming vary among persons with Alzheimer's disease (AD), including the extent to which phonemic cueing is helpful in generating the target word. This study examined neuropsychological correlates of phonemic cueing benefit and the influential effects of AD severity, estimated premorbid intellectual functioning, and apolipoprotein E genotype status.Method: Participants were 1104 individuals with mild to moderate AD who were administered the Boston Naming Test (BNT) as part of their initial neuropsychological evaluation.Results: Mild AD subjects benefited from phonemic cues significantly more than moderate AD subjects. Individuals with higher estimated premorbid IQ benefited more from phonemic cueing. Differences in phonemic cueing benefit between carriers and noncarriers of the ApoE ε4 allele were accounted for by naming ability, with carriers performing better on naming tasks compared to noncarriers. Phonemic cueing benefit uniquely contributed to cognitive performance on some semantic measures, phonemic fluency, and one nonsemantic visuospatial task.Conclusion: Individuals with probable AD who benefit more from phonemic cueing during confrontation naming tend to have higher estimated premorbid IQ and are milder in dementia severity. There is a positive association between phonemic cueing benefit and performance on select semantic measures and verbal fluency. Differences in phonemic cueing benefit between carriers and noncarriers of APOE ε4 allele can be explained by spontaneous naming performance. Results suggest complexity of underlying mechanisms involving confrontation naming, phonemic cueing, and lexical access and the factors that influence them.

Exploring supported conversation with familial caregivers of persons with dementia: a pilot study

Background

Dementia can lead to difficulties in communication between caregivers and patients. Teaching conversational strategies has been effective for a wide array of clients with acquired neurologic disorders and their caregivers. Research indicates positive results for Supported Conversation for adults with Aphasia (SCA) secondary to stroke. Applying this method to work with caregivers of individuals with dementia could prove to be a valid intervention tool. This investigation examined the applicability of SCA with individuals with dementia and their familial caregivers.

Method

Four dyads (caregiver and individual with dementia) participated in the SCA program with some adaptation for dementia. The program was 4 weeks with a pre-training and post training assessment. The Measure of Skill in Supported Conversation (MSC) and Measure of Level of Participation in Conversation (MPC) were given to measure the overall effectiveness of SCA at teaching and improving communication, respectively. A qualitative analysis of unproductive coping mechanisms also occurred. The Zarit Burden Interview (ZBI) was given to gauge caregiver burden from pre- to post-training.

Results

MSC and MPC scores were significantly improved from baseline to post training, and a significant reduction in unproductive coping behaviors also occured. ZBI scores were variable across participants.

Conclusions

Results suggest that the SCA has the potential to be used to improve communication between persons with dementia and their caregivers. Findings suggest that further research is warranted into the effectiveness of SCA in dementia.

Trial registration

Retrospectively registered 9/5/2018 ISRCTN17622451.

Connected speech and language in mild cognitive impairment and Alzheimer's disease: A review of picture description tasks

INTRODUCTION

The neuropsychological profile of people with mild cognitive impairment (MCI) and Alzheimer's disease (AD) dementia includes a history of decline in memory and other cognitive domains, including language. While language impairments have been well described in AD dementia, language features of MCI are less well understood. Connected speech and language analysis is the study of an individual's spoken discourse, usually elicited by a target stimulus, the results of which can facilitate understanding of how language deficits typical of MCI and AD dementia manifest in everyday communication. Among discourse genres, picture description is a constrained task that relies less on episodic memory and more on semantic knowledge and retrieval, within the cognitive demands of a communication context. Understanding the breadth of evidence across the continuum of cognitive decline will help to elucidate the areas of strength and need in terms of using this method as an evaluative tool for both cognitive changes and everyday functional communication.

METHOD

We performed an extensive literature search of peer-reviewed journal articles that focused on the use of picture description tasks for evaluating language in persons with MCI or AD dementia. We selected articles based on inclusion and exclusion criteria and described the measures assessed, the psychometric properties that were reported, the findings, and the limitations of the included studies.

RESULTS

36 studies were selected and reviewed. Across all 36 studies, there were 1, 127 patients with AD dementia and 274 with MCI or early cognitive decline. Multiple measures were examined, including those describing semantic content, syntactic complexity, speech fluency, vocal parameters, and pragmatic language. Discriminant validity widely reported and distinct differences in language were observable between adults with dementia and controls; fewer studies were able to distinguish language differences between typically aging adults and those with MCI.

DISCUSSION

Our review shows that picture description tasks are useful tools for detecting differences in a wide variety of language and communicative measures. Future research should expand knowledge about subtle changes to language in preclinical AD and Mild Cognitive Impairment (MCI) which may improve the utility of this method as a clinically meaningful screening tool.

Toward the Development of SMART Communication Technology: Automating the Analysis of Communicative Trouble and Repair in Dementia

BACKGROUND AND OBJECTIVES

Communication difficulties have been reported as one of the most stress-inducing aspects of caring for people with dementia. Notably, with disease progression comes an increase in the frequency of communication difficulty and a reduction in the effectiveness of attempts to remedy breakdowns in communication. The aim of the current research was to evaluate the utility of an automated discourse analysis tool (i.e., Discursis) in distinguishing between different types of trouble and repair signaling behaviors, demonstrated within conversations between people with dementia and their professional care staff.

RESEARCH DESIGN AND METHODS

Twenty conversations between people with dementia and their professional care staff were human-coded for instances of interactive/noninteractive trouble and typical/facilitative repair behaviors. Associations were then examined between these behaviors and recurrence metrics generated by Discursis.

RESULTS

Significant associations were identified between Discursis metrics, trouble-indicating, and repair behaviors.

DISCUSSION AND IMPLICATIONS

These results suggest that discourse analysis software is capable of discriminating between different types of trouble and repair signaling behavior, on the basis of term recurrence calculated across speaker turns. The subsequent recurrence metrics generated by Discursis offer a means of automating the analysis of episodes of conversational trouble and repair. This achievement represents the first step toward the future development of an intelligent assistant that can analyze conversations in real time and offers support to people with dementia and their carers during periods of communicative trouble.

[Collation of word retrieval disorders in patients with Alzheimer's dementia]

BACKGROUND

One of the first symptoms of Alzheimer's disease (AD) is word retrieval deficits. A systematic evaluation of word retrieval deficits can have an important predictive value for developing Alzheimer's disease.

OBJECTIVE

Is the test for finding word retrieval deficits (word finding = WoFi) able to detect deficits in word retrieval and does it correlate with other dementia tests?

METHODS

A word retrieval test called WoFi was developed. It is an instrument that tests word retrieval deficits based on 50 questions. A maximum of 100 points can be scored.

RESULTS

The control group scored significantly better than the AD group. Using a cut-off score of 84 points WoFi could discriminate controls from subjects with a sensitivity of 95% and a specificity of 92%.

CONCLUSION

The use of WoFi was able to test for word retrieval deficits. Application required less than 15 min and test instructions are very simple. This instrument might be useful in telehealth.

Semantic Memory in HIV-associated Neurocognitive Disorders: An Evaluation of the "Cortical" Versus "Subcortical" Hypothesis

OBJECTIVE

HIV-associated neurocognitive disorders (HAND) have historically been characterized as a subcortical condition that does not affect semantic memory; however, recent evidence suggests that the cortical regions that support semantic memory may be affected in HIV.

METHOD

The current study examined the effects of HAND on semantic memory in 85 HIV+ individuals with HAND, 193 HIV+ individuals without HAND, and 181 HIV- individuals who completed the Boston Naming Test (BNT) and the Famous Faces subtest of the Kauffman Adolescent and Adult Intelligence Test (KAIT-FF).

RESULTS

Linear regressions revealed a significant adverse effect of HAND on total scores on the BNT and the KAIT-FF (all ps < .01). Analyses of BNT errors showed that individuals with HAND committed more semantically related errors as compared to the other two study groups (all ps < .05). However, there were no group differences in rates of visually based errors, which are more commonly observed in traditional subcortical diseases (all ps > .10).

CONCLUSIONS

Results indicate that HAND may impose adverse effects on individuals' object naming and identification abilities suggestive of mild semantic deficits that parallel traditional cortical diseases such as Alzheimer's disease.

Lexical access in a bilingual speaker with dementia: Changes over time

In this article, we explore the naming skills of a bilingual English-Norwegian speaker diagnosed with Primary Progressive Aphasia, in each of his languages across three different speech contexts: confrontation naming, semi-spontaneous narrative (picture description), and conversation, and at two points in time: 12 and 30 months post diagnosis, respectively. The results are discussed in light of two main theories of lexical retrieval in healthy, elderly speakers: the Transmission Deficit Hypothesis and the Inhibitory Deficit Theory. Our data show that, consistent with the participant's premorbid use of and proficiency in the two languages, his performance in his L2 is lower than in his L1, but this difference diminishes as the disease progresses. This is the case across the three speech contexts; however, the difference is smaller in the narrative task, where his performance is very low in both languages already at the first measurement point. Despite his word finding problems, he is able to take active part in conversation, particularly in his L1 and more so at the first measurement point. In addition to the task effect, we find effects of word class, frequency, and cognateness on his naming skills. His performance seems to support the Transmission Deficit Hypothesis. By combining different tools and methods of analysis, we get a more comprehensive picture of the impact of the dementia on the speaker's languages from an intra-individual as well as an inter-individual perspective, which may be useful in research as well as in clinical practice.

Impaired acquisition of new words after left temporal lobectomy despite normal fast-mapping behavior

Word learning has been proposed to rely on unique brain regions including the temporal lobes, and the left temporal lobe appears to be especially important. In order to investigate the role of the left temporal lobe in word learning under different conditions, we tested whether patients with left temporal lobectomies (N=6) could learn novel words using two distinct formats. Previous research has shown that word learning in contrastive fast mapping conditions may rely on different neural substrates than explicit encoding conditions (Sharon et al., 2011). In the current investigation, we used a previously reported word learning task that implemented two distinct study formats (Warren and Duff, 2014): a contrastive fast mapping condition in which a picture of a novel item was displayed beside a picture of a familiar item while the novel item's name was presented aurally ("Click on the numbat."); and an explicit encoding (i.e., control) condition in which a picture of a novel item was displayed while its name was presented aurally ("This is a numbat."). After a delay, learning of the novel words was evaluated with memory tests including three-alternative forced-choice recognition, free recall, cued recall, and familiarity ratings. During the fast-mapping study condition both the left temporal lobectomy and healthy comparison groups performed well, but at test only the comparison group showed evidence of novel word learning. Our findings indicate that unilateral resection of the left temporal lobe including the hippocampus and temporal pole can severely impair word learning, and that fast-mapping study conditions do not promote subsequent word learning in temporal lobectomy populations.

Naming ability in patients with mild to moderate Alzheimer's disease: what changes occur with the evolution of the disease?

OBJECTIVES

Naming deficit is a linguistic symptom that appears in the initial phase of Alzheimer's disease, but the types of naming errors and the ways in which this deficit changes over the course of the disease are unclear. We analyzed the performance of patients with Alzheimer's disease on naming tasks during the mild and moderate phases and verified how this linguistic skill deteriorates over the course of the disease.

METHODS

A reduced version of the Boston Naming Test was administered to 30 patients with mild Alzheimer's disease, 30 patients with moderate Alzheimer's disease and 30 healthy controls. Errors were classified as verbal semantic paraphasia, verbal phonemic paraphasia, no response (pure anomia), circumlocution, unrelated verbal paraphasia, visual errors or intrusion errors.

RESULTS

The patients with moderate Alzheimer's disease had significantly fewer correct answers than did both the control group and the group with mild Alzheimer's disease. With regard to the pattern of errors, verbal semantic paraphasia errors were the most frequent errors in all three groups. Additionally, as the disease severity increased, there was an increase in the number of no-response errors (pure anomia). The group with moderate Alzheimer's disease demonstrated a greater incidence of visual errors and unrelated verbal paraphasias compared with the other two groups and presented a more variable pattern of errors.

CONCLUSIONS

Performance on nominative tasks worsened as the disease progressed in terms of both the quantity and the type of errors encountered. This result reflects impairment at different levels of linguistic processing.

On Colour, Category Effects, and Alzheimer's Disease: A Critical Review of Studies and Further Longitudinal Evidence

The role of colour in object recognition is controversial; in this study, a critical review of previous studies, as well as a longitudinal study, was conducted. We examined whether colour benefits the ability of Alzheimer's disease (AD) patients and normal controls (NC) when naming items differing in colour diagnosticity: living things (LT) versus nonliving things (NLT). Eleven AD patients were evaluated twice with a temporal interval of 3 years; 26 NC were tested once. The participants performed a naming task (colour and greyscale photographs); the impact of nuisance variables (NVs) and potential ceiling effects were also controlled. Our results showed that (i) colour slightly favoured processing of items with higher colour diagnosticity (i.e., LT) in both groups; (ii) AD patients used colour information similarly to NC, retaining this ability over time; (iii) NVs played a significant role as naming predictors in all the participants, relegating domain to a minor plane; and (iv) category effects (better processing of NLT) were present in both groups. Finally, although patients underwent semantic longitudinal impairment, this was independent of colour deterioration. This finding provides better support to the view that colour is effective at the visual rather than at the semantic level of object processing.

Object naming in epilepsy and epilepsy surgery

The ability to express oneself verbally is critical for success in academic, occupational, and social domains. Unfortunately, word-finding or "naming" difficulty is the most common cognitive complaint among individuals with temporal lobe epilepsy (TLE), and a substantial body of work over the past several decades has documented naming impairment in left (language-dominant) TLE, with further risk to naming ability following left temporal lobe resection for seizure control. With these findings well established, this paper reviews more recent work that has aimed to identify the neuroanatomical substrates of naming, understand how adverse structural and functional effects of TLE might impinge upon these brain regions, predict and potentially reduce the risk of postoperative naming decline, and begin to understand naming difficulty in TLE from a developmental perspective. Factors that have confounded interpretation and hindrances to progress are discussed, and suggestions are provided for improved empirical investigation and directions for future research.

The relation of object naming and other visual speech production tasks: a large scale voxel-based morphometric study

We report a lesion-symptom mapping analysis of visual speech production deficits in a large group (280) of stroke patients at the sub-acute stage (<120 days post-stroke). Performance on object naming was evaluated alongside three other tests of visual speech production, namely sentence production to a picture, sentence reading and nonword reading. A principal component analysis was performed on all these tests' scores and revealed a 'shared' component that loaded across all the visual speech production tasks and a 'unique' component that isolated object naming from the other three tasks. Regions for the shared component were observed in the left fronto-temporal cortices, fusiform gyrus and bilateral visual cortices. Lesions in these regions linked to both poor object naming and impairment in general visual-speech production. On the other hand, the unique naming component was potentially associated with the bilateral anterior temporal poles, hippocampus and cerebellar areas. This is in line with the models proposing that object naming relies on a left-lateralised language dominant system that interacts with a bilateral anterior temporal network. Neuropsychological deficits in object naming can reflect both the increased demands specific to the task and the more general difficulties in language processing.

Functional Changes in the Language Network in Response to Increased Amyloid β Deposition in Cognitively Intact Older Adults

Word finding symptoms are frequent early in the course of Alzheimer's disease and relate principally to functional changes in left posterior temporal cortex. In cognitively intact older adults, we examined whether amyloid load affects the network for language and associative-semantic processing. Fifty-six community-recruited subjects (52-74 years), stratified for apolipoprotein E and brain-derived neurotrophic factor genotype, received a neurolinguistic assessment, (18)F-flutemetamol positron emission tomography, and a functional MRI of the associative-semantic system. The primary measure of amyloid load was the cerebral-to-cerebellar gray matter standardized uptake value ratio in a composite cortical volume of interest (SUVR(comp)). The primary outcome analysis consisted of a whole-brain voxelwise linear regression between SUVR(comp) and fMRI response during associative-semantic versus visuoperceptual processing. Higher activity in one region, the posterior left middle temporal gyrus, correlated positively with increased amyloid load. The correlation remained significant when only the word conditions were contrasted but not for pictures. According to a stepwise linear regression analysis, offline naming reaction times correlated positively with SUVR(comp). A binary classification into amyloid-positive and amyloid-negative cases confirmed our findings. The left posterior temporal activity increase may reflect higher demands for semantic control in the presence of a higher amyloid burden.

Lexical retrieval in discourse: an early indicator of Alzheimer's dementia

We examined the progression of lexical-retrieval deficits in individuals with neuropathologically determined Alzheimer's disease (AD; n = 23) and a comparison group without criteria for AD (n = 24) to determine whether linguistic changes were a significant marker of the disease. Our participants underwent multiple administrations of a neuropsychological battery, with initial administration occurring on average 16 years prior to death. The battery included the Boston Naming Test (BNT), a letter fluency task (FAS) and written description of the Cookie Theft Picture (CTP). Repeated measures analysis revealed that the AD-group showed progressively greater decline in FAS and CTP lexical performance than the comparison group. Cross-sectional time-specific group comparisons indicated that the CTP differentiated performance between the two groups at 7-9 years prior to death and FAS and BNT only at 2-4 years. These results suggest that lexical-retrieval deficits in written discourse serve as an early indicator of AD.

A family living with Alzheimer’s disease: The communicative challenges

Alzheimer’s disease irrevocably challenges a person’s capacity to communicate with others. Earlier research on these challenges focused on the language disorders associated with the condition and situated language deficit solely in the limitations of a person’s cognitive and semantic impairments. This research falls short of gaining insight into the actual interactional experiences of a person with Alzheimer’s and their family. Drawing on a UK data set of 70 telephone calls recorded over a two-and-a-half year period (2006–2008) between one elderly woman with Alzheimer’s disease, and her daughter and son-in-law, this paper explores the role which communication (and its degeneration) plays in family relationships. Investigating these interactions, using a conversation analytic approach, reveals that there are clearly communicative difficulties, but closer inspection suggests that they arise due to the contingencies that are generated by the other’s contributions in the interaction. That being so, this paper marks a departure from the traditional focus on language level analysis and the assumption that deficits are intrinsic to the individual with Alzheimer’s, and instead focuses on the collaborative communicative challenges that arise in the interaction itself and which have a profound impact on people’s lives and relationships.

The neuropsychological profile of Alzheimer disease

Neuropsychological assessment has featured prominently over the past 30 years in the characterization of dementia associated with Alzheimer disease (AD). Clinical neuropsychological methods have identified the earliest, most definitive cognitive and behavioral symptoms of illness, contributing to the identification, staging, and tracking of disease. With increasing public awareness of dementia, disease detection has moved to earlier stages of illness, at a time when deficits are both behaviorally and pathologically selective. For reasons that are not well understood, early AD pathology frequently targets large-scale neuroanatomical networks for episodic memory before other networks that subserve language, attention, executive functions, and visuospatial abilities. This chapter reviews the pathognomonic neuropsychological features of AD dementia and how these differ from "normal," age-related cognitive decline and from other neurodegenerative diseases that cause dementia, including cortical Lewy body disease, frontotemporal lobar degeneration, and cerebrovascular disease.

Verbal Play as an Interactional Discourse Resource in Early Stage Alzheimer's Disease

BACKGROUND: Verbal play, the creative and playful use of language to make puns, rhyme words, and tease, is a pervasive and enjoyable component of social communication and serves important interpersonal functions. The current study examines the use of verbal play in the communicative interactions of individuals with Alzheimer's disease as part of a broader program of research on language-and-memory-in-use. AIMS: To document the frequency of verbal play in the communicative interactions of individuals with very mild Alzheimer's disease (AD) and their familiar communication partners. To characterize the interactional forms, resources, and functions of playful episodes. METHODS: Using quantitative group comparisons and detailed discourse analysis, we analyzed verbal play in the interactional discourse of five participants with very mild AD and five healthy (demographically matched) comparison participants. Each participant interacted with a familiar partner while completing a collaborative referencing task, and with a researcher between task trials. RESULTS: A total of 1,098 verbal play episodes were coded. Despite being in the early stages of AD, all the AD participants used verbal play. There were no significant group differences in the frequency of verbal play episodes or in the interactional forms, resources, or functions of those playful episodes between AD and healthy comparison pair sessions. CONCLUSIONS: The successful use of verbal play in the interactions of individuals with very mild AD and their partners highlights an area of preserved social communication. These findings represent an important step, both clinically and for research, in documenting the rich ways that individuals with early stage AD orchestrate interactionally meaningful communication with their partners through the use of interactional discourse resources like verbal play. This work also offers a promising clinical tool for tracking and targeting verbal play across disease progression.

Anomia as a marker of distinct semantic memory impairments in Alzheimer's disease and semantic dementia

OBJECTIVE

Many neurologically constrained models of semantic memory have been informed by two primary temporal lobe pathologies: Alzheimer's disease (AD) and Semantic Dementia (SD). However, controversy persists regarding the nature of the semantic impairment associated with these patient populations. Some argue that AD presents as a disconnection syndrome in which linguistic impairment reflects difficulties in lexical or perceptual means of semantic access. In contrast, there is a wider consensus that SD reflects loss of core knowledge that underlies word and object meaning. Object naming provides a window into the integrity of semantic knowledge in these two populations.

METHOD

We examined naming accuracy, errors and the correlation of naming ability with neuropsychological measures (semantic ability, executive functioning, and working memory) in a large sample of patients with AD (n = 36) and SD (n = 21).

RESULTS

Naming ability and naming errors differed between groups, as did neuropsychological predictors of naming ability. Despite a similar extent of baseline cognitive impairment, SD patients were more anomic than AD patients.

CONCLUSIONS

These results add to a growing body of literature supporting a dual impairment to semantic content and active semantic processing in AD, and confirm the fundamental deficit in semantic content in SD. We interpret these findings as supporting of a model of semantic memory premised upon dynamic interactivity between the process and content of conceptual knowledge.

Effects of semantic elaboration and typicality on picture naming in Alzheimer disease

PURPOSE

Individuals with probable Alzheimer disease (pAD) are frequently impaired at picture naming. This study examined whether a semantic elaboration task would facilitate naming in pAD, and whether training either semantically typical or atypical stimulus items facilitated generalized improvement in picture naming and category generation tasks.

METHODS

Twelve adults with mild-moderate pAD participated in the study. Participants performed an experimental semantic elaboration training task using a subset of typical items from one category and atypical items from another category. The third category, acted as a control (i.e., no items were trained). The study assessed change in category generation and a picture naming within the three target categories.

RESULTS

Individuals showed significantly improved category generation and naming, but changes were not limited to trained categories. Naming of trained atypical items improved significantly. Participants showed significantly improved naming of untrained typical items from categories trained with typical items.

CONCLUSIONS

Semantic elaboration of typical items within a semantic category can lead to generalized improvement in other typical items in the category in mild-moderate pAD. This is consistent with theories postulating that typical category items share overlapping distributed representations. Further exploration of the effects of semantic elaboration on word-finding in pAD is warranted, especially the possibility of within-category generalization.

Getting the hang of it: preferential gist over verbatim story recall and the roles of attentional capacity and the episodic buffer in Alzheimer disease

Story recall in Alzheimer disease (AD) is typically used as a measure of episodic memory, but the degree to which recall is dependent on available attentional resources is not fully understood. The current study investigated how measures of attention were associated to verbatim recall (exact reproduction) or gist recall (relevant semantic meaning). Sixteen participants with AD and 16 age-matched healthy older adults recalled a story on immediate free recall and recognition. Controls recalled more units overall than AD. A group X response interaction revealed more gist than verbatim recall in AD, but those with mild disease generated approximately the same number gist responses as controls. For each group, qualitatively different attentional resources were associated with recall units. In controls, verbatim units correlated positively with primacy serial position items of the California Verbal Learning Test II (CVLTII), suggesting that episodic buffer resources may be associated with story recall. In AD, gist units were positively correlated with digits forward, but inversely related to the CVLTII primacy region items, suggesting reliance on low-level capacity resources. Possible explanations of the impaired performance in AD may be a bias in favor of gist processing, poor verbatim encoding, and/or processing failure at the level of the episodic buffer.

Auditory confrontation naming in Alzheimer's disease

Naming is a fundamental aspect of language and is virtually always assessed with visual confrontation tests. Tests of the ability to name objects by their characteristic sounds would be particularly useful in the assessment of visually impaired patients, and may be particularly sensitive in Alzheimer's disease (AD). We developed an auditory naming task, requiring the identification of the source of environmental sounds (i.e., animal calls, musical instruments, vehicles) and multiple-choice recognition of those not identified. In two separate studies mild-to-moderate AD patients performed more poorly than cognitively normal elderly on the auditory naming task. This task was also more difficult than two versions of a comparable visual naming task, and correlated more highly with Mini-Mental State Exam score. Internal consistency reliability was acceptable, although ROC analysis revealed auditory naming to be slightly less successful than visual confrontation naming in discriminating AD patients from normal participants. Nonetheless, our auditory naming task may prove useful in research and clinical practice, especially with visually impaired patients.

Cognition, language, and clinical pathological features of non-Alzheimer's dementias: an overview

There are many distinct forms of dementia whose pharmacological and behavioral management differ. Differential diagnosis among the dementia variants currently relies upon a weighted combination of genetic and protein biomarkers, neuroanatomical integrity, and behavior. Diagnostic specificity is complicated by a high degree of overlap in the initial presenting symptoms across dementia subtypes. For this reason, reliable markers are of considerable diagnostic value. Communication disorders have proven to be among the strongest predictors for discriminating among dementia subtypes. As such, speech-language pathologists may be poised to make an increasingly visible contribution to dementia diagnosis and its ongoing management. The value and durability of this potential contribution, however, demands an improved discipline-wide knowledge base about the unique features associated with different dementia variants. To this end we provide an overview of cognition, language, and clinical pathological features of four of the most common non-Alzheimer's dementias: frontotemporal dementia, vascular dementia, Lewy body disease dementia, and Parkinson's disease dementia.

LEARNING OUTCOMES

Readers will learn characteristics and distinguishing features of several non-Alzheimer's dementias, including Parkinson's disease dementia, frontotemporal dementia, vascular dementia, and Lewy body dementia. Readers will also learn to distinguish between several variants of frontotemporal dementia. Finally, readers will gain knowledge of the term primary progressive aphasia as it relates to the aforementioned dementia etiologies.

What intact social cognition and social behavior reveal about cognition in the moderate stage of Alzheimer’s disease

This case study describes a person in the moderate stage of Alzheimer’s disease (AD) and examines her intact social cognition and healthy, appropriate social behavior as reflected by the existence of Kitwood and Bredin’s indicators of relative well-being. The subject of the study was observed over the course of four months at an adult day center. Findings (1) reveal that an apparent dissociation exists between cognitive function as measured by standardized assessments and cognitive function as revealed in social situations, and (2) call into question the notions that (a) cognitive losses, as measured by neuropsychological tests, cause defective social behavior and (b) standard tests are, generalizable ways of measuring different aspects of cognitive function. The meaning of these findings for practitioners and other caregivers is discussed. Further research is required to elucidate the degree to which the present findings may be generalized.

Increased functional brain response during word retrieval in cognitively intact older adults at genetic risk for Alzheimer's disease

Recent language studies in aging and dementia provide two complementary lines of evidence that: (1) measures of semantic knowledge and word-finding ability show declines comparable to those of episodic memory, and greater impairment than executive function measures, during the prodromal period of Alzheimer's disease and (2) cognitively intact older adult carriers of the apolipoprotein E (APOE) epsilon4 allele also demonstrate poorer object naming than their low-risk peers. Given that possible changes in the neural substrates of word retrieval (e.g., Broca's area and fusiform gyrus) in at-risk adults may signal impending cognitive decline and serve as a prodromal marker of AD, we examined whether APOE epsilon4 carriers exhibit changes in brain response in regions subserving word retrieval and semantic knowledge. Eleven cognitively intact APOE epsilon4 older adults and 11 age, education, and family history of AD-matched APOE epsilon3 adults named aloud photographs of animals, tools, and vehicles during event-related fMRI. Results showed that, in the face of equivalent naming accuracy, APOE epsilon4 adults demonstrated more widespread brain response with greater signal change in the left fusiform gyrus, bilateral medial prefrontal cortex, and right perisylvian cortex. Findings are discussed in the context of possible compensatory mechanisms invoked to maintain performance in those at genetic risk for AD.

Temporal parameters of spontaneous speech in Alzheimer's disease

This paper reports on four temporal parameters of spontaneous speech in three stages of Alzheimer's disease (mild, moderate, and severe) compared to age-matched normal controls. The analysis of the time course of speech has been shown to be a particularly sensitive neuropsychological method to investigate cognitive processes such as speech planning and production. The following parameters of speech were measured in Hungarian native-speakers with Alzheimer's disease and normal controls: articulation rate, speech tempo, hesitation ratio, and rate of grammatical errors. Results revealed significant differences in most of these speech parameters among the three Alzheimer's disease groups. Additionally, the clearest difference between the normal control group and the mild Alzheimer's disease group involved the hesitation ratio, which was significantly higher in the latter group. This parameter of speech may have diagnostic value for mild-stage Alzheimer's disease and therefore could be a useful aid in medical practice.

Effects of semantic relations, repetition of words, and list length in word list recall of Alzheimer's patients

INTRODUCTION

Semantic relations among words and repetition enhance free recall, but it is unknown if these facilitating factors are effective in dementia.

METHOD

Alzheimer's patients (MILD-Alz, MOD-Alz) were compared to healthy elderly. Fifteen-word lists were read out to the subjects. In four sets of lists the words in intermediary input positions were semantically related or not, or the midlist words were repeated, or they were repeated and semantically related.

RESULTS

The usual third peak of recall of semantically related words was not observed in MOD-Alz, repetition of words did not increase recall of the patients, and the combination of relatedness and repetition benefited only MID-Alz. In a second experiment, with related or unrelated midlist words, and list length shortened from 15 to 9 words, semantic facilitation was observed in mild and moderate Alzheimer s patients, although diminished compared to controls.

CONCLUSION

Progression of dementia turns facilitating factors of recall less effective.

Auditory responsive naming versus visual confrontation naming in dementia

Dysnomia is typically assessed during neuropsychological evaluation through visual confrontation naming. Responsive naming to description, however, has been shown to have a more distributed representation in both fMRI and cortical stimulation studies. While naming deficits are common in dementia, the relative sensitivity of visual confrontation versus auditory responsive naming has not been directly investigated. The current study compared visual confrontation naming and auditory responsive naming in a dementia sample of mixed etiologies to examine patterns of performance across these naming tasks. A total of 50 patients with dementia of various etiologies were administered visual confrontation naming and auditory responsive naming tasks using stimuli that were matched in overall word frequency. Patients performed significantly worse on auditory responsive naming than visual confrontation naming. Additionally, patients with mixed Alzheimer's disease/vascular dementia performed more poorly on auditory responsive naming than did patients with probable Alzheimer's disease, although no group differences were seen on the visual confrontation naming task. Auditory responsive naming correlated with a larger number of neuropsychological tests of executive function than did visual confrontation naming. Auditory responsive naming appears to be more sensitive to effects of increased of lesion burden compared to visual confrontation naming. We believe that this reflects more widespread topographical distribution of auditory naming sites within the temporal lobe, but may also reflect the contributions of working memory and cognitive flexibility to performance.

Word sequence production in cognitive decline: forward ever, backward never

Backward recall of automatic word sequences involves declarative and working memory abilities known to be impaired in the early stages of cognitive decline. Yet its utility in the diagnosis of mild cognitive impairment and mild dementia has not been studied in detail. We analysed word sequence production in 234 participants drawn from three categories: subjective cognitive impairment, mild cognitive impairment, and mild dementia in Alzheimer's disease. The names of the months were used as a diagnostic target for investigating forward versus backward sequence production. Forward production remained normal across categories. In contrast, backward speed was significantly decreased in mild cognitive impairment. In dementia both speed and accuracy were impaired. Backward production had significant diagnostic classificatory power. We conclude that word sequence production yields data relevant to the diagnosis of dementia with a minimum of time and expense.