Proper names in patients with early Alzheimer's disease

Associations between recall of proper names in story recall and CSF amyloid and tau in adults without cognitive impairment

Neuropsychological measures sensitive to decline in the preclinical phase of Alzheimer's disease are needed. We previously demonstrated that higher amyloid-beta (Aβ) assessed by positron emission tomography in adults without cognitive impairment was associated with recall of fewer proper names in Logical Memory story recall. The current study investigated the association between proper names and cerebrospinal fluid biomarkers (Aβ42/40, phosphorylated tau181 [pTau181], neurofilament light) in 223 participants from the Wisconsin Registry for Alzheimer's Prevention. We assessed associations between biomarkers and delayed Logical Memory total score and proper names using binary logistic regressions. Sensitivity analyses used multinomial logistic regression and stratified biomarker groups. Lower Logical Memory total score and proper names scores from the most recent visit were associated with biomarker positivity. Relatedly, there was a 27% decreased risk of being classified Aβ42/40+/pTau181+ for each additional proper name recalled. A linear mixed effects model found that longitudinal change in proper names recall was predicted by biomarker status. These results demonstrate a novel relationship between proper names and Alzheimer's disease-cerebrospinal fluid pathology.

Stimulus material selection for the Dutch famous faces test for older adults

Worldwide, approximately 22% of all individuals aged 50 years and older are currently estimated to fall somewhere on the Alzheimer's disease (AD) continuum, which can be roughly divided into preclinical AD, mild cognitive impairment (MCI), and AD dementia. While episodic memory loss (among other aspects) is typically required for a diagnosis of AD dementia, MCI is said to have occurred when cognitive impairment (including memory loss) is worse than expected for the person's age but not enough to be classified as dementia. On the other hand, preclinical AD can currently only be detected using biomarkers; clinical symptoms are not apparent using traditional neuropsychological tests. The main aim of the current paper was to explore the possibility of a test which could distinguish preclinical AD from normal aging. Recent scientific evidence suggests that the Famous Faces Test (FFT) could differentiate preclinical AD from normal aging up to 5 years before a clinical AD diagnosis. Problematic with existing FFTs is the selection of stimulus material. Faces famous in a specific country and a specific decade might not be equally famous for individuals in another country or indeed for people of different ages. The current article describes how famous faces were systematically selected and chosen for the Dutch older (60+) population using five steps. The goal was to design and develop short versions of the FFT for Dutch older adults of equivalent mean difficulty. In future work, these nine parallel versions will be necessary for (a) cross-sectional comparison as well as subsequent longitudinal assessment of cognitively normal and clinical groups and (b) creating personalized norms for the normal aged controls that could be used to compare performance within individuals with clinical diagnoses. The field needs a simple, cognitive test which can distinguish the earliest stages of the dementia continuum from normal aging.

Norms for pictures of proper names: contrasting famous people and well-known places in younger and older adults

Proper names comprise a class of labels that arbitrarily nominate specific entities, such as people and places. Compared to common nouns, retrieving proper names is more challenging. Thus, they constitute good alternative semantic categories for psycholinguistic and neurocognitive research and intervention. The ability to retrieve proper names is known to decrease with aging. Likewise, their retrieval may differ across their different categories (e.g., people and places) given their specific associated knowledge. Therefore, proper names' stimuli require careful selection due to their high dependence on prior experiences. Notably, normative datasets for pictures of proper names are scarce and hardly have considered the influence of aging and categories. The current study established culturally adapted norms for proper names' pictures (N = 80) from an adult sample (N = 107), in psycholinguistic measures (naming and categorization scores) and evaluative dimensions (fame, familiarity, distinctiveness, arousal, and representational quality). These norms were contrasted across different categories (famous people and well-known places) and age groups (younger and older adults). Additionally, the correlations between all variables were examined. Proper names' pictures were named and categorized above chance and overall rated as familiar, famous, distinctive, and of high representational quality. Age effects were observed across all variables, except familiarity. Category effects were occasionally observed. Finally, the correlations between the psycholinguistic measures and all rated dimensions suggest the relevance of controlling for these dimensions when assessing naming abilities. The current norms provide a relevant aging-adapted dataset that is publicly available for research and intervention purposes.

Famous faces naming test predicts conversion from mild cognitive impairment to Alzheimer's disease

The presence of semantic memory dysfunction in Alzheimer's disease (AD) has been widely investigated. Several studies have showed a higher degree of impairment in naming persons and objects, compared to general semantic knowledge in early stages of AD. The aim of this study was to investigate if the Famous Faces Naming Test can help to differentiate patients with mild cognitive impairment (MCI) who will progress to AD and those who will not. A Famous Faces Naming Test was administered to 17 patients with MCI who did not convert to AD and eight patients with MCI who converted to AD 2 years later. MCI patients who converted to AD 2 years later performed significantly worse on Famous Faces Naming Test compared to MCI patients who did not convert over that time period. A neuropsychological task of semantic knowledge of famous people may be useful in the early diagnosis of Alzheimer's disease.

Protective factors for subjective cognitive decline individuals: trajectories and changes in a longitudinal study with Italian elderly

BACKGROUND AND PURPOSE

Many different factors have been hypothesized to modulate cognition in an aging population according to their functioning at baseline.

METHODS

This retrospective study quantifies the relative contribution of age and sex as demographic factors, comorbidity, education and occupation (classified with the International Standard Classification of Occupation 2008) as cognitive reserve proxies in accounting for cognitive aging. All participants (3081) were evaluated at baseline with a complete neuropsychological test battery (T1) and those with unimpaired profiles were classified as subjective cognitive decline, those mildly impaired as mild neurocognitive decline and those severely impaired as major neurocognitive decline. From the first assessment 543 individuals were assessed a second time (T2), and 125 a third time (T3). Depending on whether they maintained or worsened their profile, based on their initial performance, participants were then classified as resistant or declining.

RESULTS

At baseline, all individuals showed education and occupation as the best predictors of performance, in addition to age. Furthermore, across assessments, the resistant had higher levels of education and occupation than the declining. In particular, the education and occupation predicted cognitive performance in all groups considered, from the subjective cognitive decline to the one with the most severely impaired participants.

CONCLUSIONS

This study highlights the role of working activity in protecting from cognitive decline across all fragile elderly groups and even more so the individuals who are at very high risk of decline.

A Systematic Review of Normative Studies Using Images of Common Objects

Common objects comprise living and non-living things people interact with in their daily-lives. Images depicting common objects are extensively used in different fields of research and intervention, such as linguistics, psychology, and education. Nevertheless, their adequate use requires the consideration of several factors (e.g., item-differences, cultural-context and confounding correlated variables), and careful validation procedures. The current study presents a systematic review of the available published norms for images of common objects. A systematic search using PRISMA guidelines indicated that despite their extensive use, the production of norms for such stimuli with adult populations is quite limited (N = 55), particularly for more ecological images, such as photos (N = 14). Among the several dimensions in which the items were assessed, the most commonly referred in our sample were familiarity, visual complexity and name agreement, illustrating some consistency across the reported dimensions while also indicating the limited examination of other potentially relevant dimensions for image processing. The lack of normative studies simultaneously examining affective, perceptive and semantic dimensions was also documented. The number of such normative studies has been increasing in the last years and published in relevant peer-reviewed journals. Moreover, their datasets and norms have been complying with current open science practices. Nevertheless, they are still scarcely cited and replicated in different linguistic and cultural contexts. The current study brings important theoretical contributions by characterizing images of common objects stimuli and their culturally-based norms while highlighting several important features that are likely to be relevant for future stimuli selection and evaluative procedures. The systematic scrutiny of these normative studies is likely to stimulate the production of new, robust and contextually-relevant normative datasets and to provide tools for enhancing the quality of future research and intervention.

Proper names from story recall are associated with beta-amyloid in cognitively unimpaired adults at risk for Alzheimer's disease

Due to advances in the early detection of Alzheimer's disease (AD) biomarkers including beta-amyloid (Aβ), neuropsychological measures that are sensitive to concurrent, subtle changes in cognition are critically needed. Story recall tasks have shown sensitivity to early memory declines in persons with mild cognitive impairment (MCI) and early stage dementia, as well as in persons with autosomal dominantly inherited AD up to 10 years prior to a dementia diagnosis. However, the evidence is inconclusive regarding relationships between evidence of Aβ and story recall measures. Because story recall tasks require the encoding and delayed retrieval of several lexical-semantic categories, such as proper names, verbs, and numerical expressions, and because lexical categories have been shown to be differentially impaired in persons with MCI, we focused on item-level analyses of lexical-semantic retrieval from a quintessential story recall task, Logical Memory from the Wechsler Memory Scale-Revised. Our objective was to investigate whether delayed recall of lexical categories (proper names, verbs and/or numerical expressions), as well as the traditional total score measure, was associated with "preclinical AD," or cognitively unimpaired adults with positive Aβ deposition on positron emission tomography (PET) neuroimaging using Pittsburgh Compound B (PiB). We developed an item-level scoring system, in which we parsed items into lexical categories and examined the immediate and delayed recall of these lexical categories from 217 cognitively unimpaired participants from the Wisconsin Registry for Alzheimer's Prevention (WRAP). We performed binary logistic regression models with story recall score as predictor and Aβ status (positive/negative) as the outcome. Using baseline Logical Memory data, proper names from delayed story recall were significantly associated with Aβ status, such that participants who recalled more proper names were less likely to be classified as PiB(+) (odds ratio = .58, p = .01). None of the other story recall variables, including total score, were associated with PiB status. Secondary analyses determined that immediate recall of proper names was not significantly associated with Aβ, suggesting a retrieval deficit rather than that of encoding. The present findings suggest that lexical semantic retrieval measures from existing story recall tasks may be sensitive to Aβ deposition, and may provide added utility to a widely-used, long-standing neuropsychological test for early detection of cognitive decline on the AD continuum.

Communicative Strengths in Severe Aphasia: The Famous People Protocol and Its Value in Planning Treatment

Purpose This clinical focus article describes the development and use of the Famous People Protocol (FPP), a clinical tool for observing the strategies people with severe aphasia (PWSA) can use to communicate when speech is limited. Its goal is to provide a systematic approach to identifying individually appropriate communication strategies for PWSA. Method Though not a test, the FPP's development and pilot testing were consonant with qualitative approaches to test development. Eighty-one people with aphasia and 37 nonaphasic participants were given the current version of FPP and the Western Aphasia Battery-Revised (WAB-R; Kertesz, 2006). This clinical focus article reports on the 36 PWA who scored near or below the mean WAB score of the larger group. Results The FPP has a maximum score of 100 based on (a) identification of famous people in different categories, entertainers, athletes, U.S. presidents, sports figures, and internationally famous people, and (b) responses to additional questions about the famous people. Identification is scored quantitatively on a 3-point scale, and question responses are scored correct (1) or incorrect (0). Mean scores for the PWSA and control groups were 54.6 and 95.2, respectively. FPP and WAB-R scores were moderately correlated (r = .67). Qualitative results describe the variety of strategies that PWSA used on the FPP. Conclusions The FPP is a way for clinicians to engage PWSA in an activity that can reveal personally relevant strategies to help PWSA communicate more effectively. The strategies can then become the basis for subsequent training on using them conversationally. Appendixes provide examples of clinical approaches.

A normative study for photographs of celebrities in Spain

Research on familiar faces has recurrently been conducted in different domains, such as, psycholinguistics, memory, attention, face processing, aging studies, etc. In general, photographs of celebrities, their proper names, or their occupations have been the materials mainly employed in those types of studies. These stimuli are, however, very constrained by the geographic and sociocultural contexts in which the studies are conducted, and, in spite of their relevance for psychological research, there are no normative studies for celebrities in Spain. With the aim of filling this gap, the photographs and names of the 118 most frequently produced celebrities in Spain were collected. For each celebrity, values for 13 different indices (including psycholinguistic properties, naming times, and emotional indicators) were obtained from a young adult Spanish sample. Regression analyses on the data indicated that the main determinant in naming times and ToTs was the percentage of correct responses. Face agreement was also a significant predictor of ToTs. Results were compared with previous celebrity norms in other languages, and discussed in relation to the current models of face processing. These norms are likely to make a useful contribution to the design of more controlled research and applied tools in Psychology.

Semantic memory and depressive symptoms in patients with subjective cognitive decline, mild cognitive impairment, and Alzheimer's disease

BACKGROUND

Semantic memory may be impaired in clinically recognized states of cognitive impairment. We investigated the relationship between semantic memory and depressive symptoms (DS) in patients with cognitive impairment.

METHODS

323 cognitively healthy controls and 848 patients with subjective cognitive decline (SCD), mild cognitive impairment (MCI), and Alzheimer's disease (AD) dementia were included. Semantic knowledge for famous faces, world capitals, and word vocabulary was investigated.

RESULTS

Compared to healthy controls, we found a statistically significant difference of semantic knowledge in the MCI groups and the AD group, respectively. Results of the SCD group were mixed. However, two of the three semantic memory measures (world capitals and word vocabulary) showed a significant association with DS.

CONCLUSIONS

We found a difference in semantic memory performance in MCI and AD as well as an association with DS. Results suggest that the difference in semantic memory is due to a storage loss rather than to a retrieval problem.

Naming unique entities in the semantic variant of primary progressive aphasia and Alzheimer's disease: Towards a better understanding of the semantic impairment

While the semantic variant of primary progressive aphasia (svPPA) is characterized by a predominant semantic memory impairment, episodic memory impairments are the clinical hallmark of Alzheimer's disease (AD). However, AD patients also present with semantic deficits, which are more severe for semantically unique entities (e.g. a famous person) than for common concepts (e.g. a beaver). Previous studies in these patient populations have largely focused on famous-person naming. Therefore, we aimed to evaluate if these impairments also extend to other semantically unique entities such as famous places and famous logos. In this study, 13 AD patients, 9 svPPA patients, and 12 cognitively unimpaired elderly subjects (CTRL) were tested with a picture-naming test of non-unique entities (Boston Naming Test) and three experimental tests of semantically unique entities assessing naming of famous persons, places, and logos. Both clinical groups were overall more impaired at naming semantically unique entities than non-unique entities. Naming impairments in AD and svPPA extended to the other types of semantically unique entities, since a CTRL>AD>svPPA pattern was found on the performance of all naming tests. Naming famous places and famous persons appeared to be most impaired in svPPA, and both specific and general semantic knowledge for these entities were affected in these patients. Although AD patients were most significantly impaired on famous-person naming, only their specific semantic knowledge was impaired, while general knowledge was preserved. Post-hoc neuroimaging analyses also showed that famous-person naming impairments in AD correlated with atrophy in the temporo-parietal junction, a region functionally associated with lexical access. In line with previous studies, svPPA patients' impairment in both naming and semantic knowledge suggest a more profound semantic impairment, while naming impairments in AD may arise to a greater extent from impaired lexical access, even though semantic impairment for specific knowledge is also present. These results highlight the critical importance of developing and using a variety of semantically-unique-entity naming tests in neuropsychological assessments of patients with neurodegenerative diseases, which may unveil different patterns of lexical-semantic deficits.

Cognitive dysfunction in severe chronic obstructive pulmonary disease (COPD) with or without Long-Term Oxygen Therapy (LTOT)

Background

Chronic Obstructive Pulmonary Disease (COPD) is a progressive respiratory condition which can lead to comorbidities of variable severity, cognitive dysfunction included. The role of supplemental oxygen in preventing COPD-induced cognitive deterioration is still debated, but only episodically investigated. The aim of this study was to compare the cognitive pattern of hypoxemic COPD subjects treated with long-term oxygen (LTOT) to that of patients of comparable severity assuming oxygen on irregular basis, and to normal reference values.

Methods

Lung function, arterial blood gases, health status, and cognitive function measured by means of four psychometric tests focusing different domains of cognition (such as: MMSE, Clock test; TMT-A; TMT-B) were assessed in 146 well matched hypoxemic COPD patients (males n = 96, 66%; mean age = 70.5 ± 12.9). Seventy-three patients were assuming long-term oxygen (LTOT), while the remaining seventy-three were only using oxygen as needed (AN). Regarding statistics, t test and ANOVA (Duncan test) were used to analyze data, assuming a p < 0.05 as the lowest limit of significance.

Results

Even though all COPD patients showed a poorer psychometric profile vs corresponding normal reference values, LTOT patients showed a lower prevalence of severe deterioration in cognition. Also the extent of impairment was significantly lower in these patients when assessed by TMT-A and TMT-B (p < 0.012 and 0.001, respectively), but not when measured by MMSE and Clock test (both p = ns). Several domains of cognition are variably affected by persistent hypoxemia in COPD patients. A panel of psychometric tools is needed for identifying the pattern of cognitive dysfunctions in these patients. Memory and attention (functions assessed by MMSE and Clock test) are only mildly-moderately affected, while visual processing, reproduction of numeric sequences, cognition flexibility, and shifting capacity (functions assessed by TMT-A and TMT-B) are much more deteriorated (p < 0.012 and p < 0.001, respectively).

Conclusions

Only LTOT allows to preserve significantly (p < 0.022) cognitive functions from the COPD-induced deterioration. This assumption is of strategic value for COPD patients who are prescribed long-term oxygen because they frequently are not aware of the cognitive risks related to their condition.

Electro-cortical manifestations of common vs. proper name processing during reading

The main purpose of the present study was to investigate how proper and common nouns are represented in the brain independent of memory retrieval processes. Participants were instructed to perform a lexical decision task while dense-array EEG was continuously recorded. Both ERP components (namely N400 and P300) and swLORETA suggested that proper name processing engaged a more widespread neural network and required more cognitive resources than common noun processing. Overall, our results come down in favor of the hypothesis that specific effects of proper vs. common noun processing exist, and they suggest a possible neuro-functional segregation of proper vs. common noun processing. The difference in proper and common noun processing seems to emerge at the level of storage or representation of lexical knowledge, and it may crucially depend on their semantic characteristics.

Extent and prevalence of cognitive dysfunction in chronic obstructive pulmonary disease, chronic non-obstructive bronchitis, and in asymptomatic smokers, compared to normal reference values

Background

Chronic obstructive pulmonary disease (COPD) can affect cognition. The effects of other less severe chronic airway disorders on cognition remain to be clarified. This study aimed to measure and compare cognitive deterioration in subjects with COPD, subjects with chronic non-obstructive bronchitis (CNOB), and asymptomatic smokers (AS), and to relate the corresponding prevalence to several demographic and clinical variables and to normal reference values.

Methods

Four hundred and two subjects (COPD n=229, CNOB n=127, and AS n=46) of comparable age were included in the study. Cognitive impairment was assessed using the Mini Mental Status test, the Clock Drawing test, and the Trail Making test A and B.

Results

The extent and prevalence of cognitive deterioration was greater in COPD subjects, followed by CNOB subjects and AS (P<0.001). The Medical Research Council and COPD Assessment test scores, forced expiratory volume in the first second predicted, and arterial partial pressure of O₂ and of CO₂ were related to the extent and the prevalence of cognitive deterioration. COPD subjects, CNOB subjects, and AS aged 40–69 years showed the greatest cognitive impairment (P<0.01 compared to normal values). This was particularly clear in COPD subjects.

Conclusion

Cognitive impairment may start at the early stages of chronic airway damage and progress with a worsening of the respiratory condition. Indeed, the greatest cognitive deterioration was seen in COPD subjects. Cognition impairment may contribute to explaining the insufficient adherence to therapeutic plans and strategies, and the increasing social costs in respiratory subjects.

Does tip-of-the-tongue for proper names discriminate amnestic mild cognitive impairment?

BACKGROUND

Difficulty in retrieving people's names is very common in the early stages of Alzheimer's disease and mild cognitive impairment. Such difficulty is often observed as the tip-of-the-tongue (TOT) phenomenon. The main aim of this study was to explore whether a famous people's naming task that elicited the TOT state can be used to discriminate between amnestic mild cognitive impairment (aMCI) patients and normal controls.

METHODS

Eighty-four patients with aMCI and 106 normal controls aged over 50 years performed a task involving naming 50 famous people shown in pictures. Univariate and multivariate regression analyses were used to study the relationships between aMCI and semantic and phonological measures in the TOT paradigm.

RESULTS

Univariate regression analyses revealed that all TOT measures significantly predicted aMCI. Multivariate analysis of all these measures correctly classified 70% of controls (specificity) and 71.6% of aMCI patients (sensitivity), with an AUC (area under curve ROC) value of 0.74, but only the phonological measure remained significant. This classification value was similar to that obtained with the Semantic verbal fluency test.

CONCLUSIONS

TOTs for proper names may effectively discriminate aMCI patients from normal controls through measures that represent one of the naming processes affected, that is, phonological access.

Is knowledge of famous people compromised in mild cognitive impairment?

OBJECTIVE

: This study addressed the issue of whether person naming deficits in mild cognitive impairment (MCI) occurred with deficits in person semantic knowledge and whether person knowledge was more impaired than general semantics.

BACKGROUND

: Recent definitions of MCI are beginning to encompass cognitive impairments outside the domain of episodic memory. Increasing evidence suggests that semantic memory may also be compromised in this patient group, including tasks of person naming and identification.

METHODS

: Thirteen MCI patients and 14 control subjects matched for age and education performed parallel semantic batteries designed to probe person and general semantic knowledge.

RESULTS

: On the person battery, the MCI patients demonstrated impairment relative to controls, on tasks of category fluency, naming, identification, verbal and nonverbal associative and sorting tasks, as well as matching names to faces. By contrast, on the general semantic battery impairments, they were impaired only on category fluency and the nonverbal sorting and associative tasks. A composite measure of person knowledge tasks was also sensitive to disease severity as measured by Mini-Mental State Examination.

CONCLUSIONS

: These results support the existence of deficits in MCI across various domains of person knowledge, and the suggestion that deterioration of unique semantic exemplars may be sensitive to incipient Alzheimer disease.

Reduced verbal fluency for proper names in nondemented patients with Parkinson's disease: a quantitative and qualitative analysis

There has been an increasing interest within neuropsychology in comparing verbal fluency for different grammatical classes (e.g., verb generation vs. noun generation) in neurological populations, including Parkinson's disease (PD). However, to our knowledge, few studies have compared verbal fluency for common nouns and proper names in PD. Common nouns and proper names differ in terms of their semantic characteristics, as categories of common nouns are organized hierarchically based on semantics, while categories of proper nouns lack a well-defined semantic organization. In addition, there is accumulating evidence that the retrieval of these distinct grammatical classes are subserved by somewhat distinct neural systems. Given that verbal fluency deficits are among the first impairments to emerge in PD, and that such deficits are predictors of future cognitive decline, it is important to examine all aspects of verbal fluency in this population. For the current study, we compared the performance of a group of 32 nondemented PD patients with 32 healthy participants (HP) on verbal fluency tasks for common nouns (animals) and proper names (boys' first names). A significant interaction between verbal fluency task and diagnostic status emerged, as the PD group performed significantly worse on only the proper name fluency task. This finding may reflect the absence of well-defined semantic organization that structures the verbal search for first names, thus placing a greater onus on strategic or "executive" verbal retrieval processes.

Language performance in Alzheimer's disease and mild cognitive impairment: a comparative review

Mild cognitive impairment (MCI) manifests as memory impairment in the absence of dementia and progresses to Alzheimer's disease (AD) at a rate of around 15% per annum, versus 1-2% in the general population. It thus constitutes a primary target for investigation of early markers of AD. Language deficits occur early in AD, and performance on verbal tasks is an important diagnostic criterion for both AD and MCI. We review language performance in MCI, compare these findings to those seen in AD, and identify the primary issues in understanding language performance in MCI and selecting tasks with diagnostic and prognostic value.

Naming of objects, faces and buildings in mild cognitive impairment

Accruing evidence suggests that the cognitive deficits in very early Alzheimer's Disease (AD) are not confined to episodic memory, with a number of studies documenting semantic memory deficits, especially for knowledge of people. To investigate whether this difficulty in naming famous people extends to other proper names based information, three naming tasks - the Graded Naming Test (GNT), which uses objects and animals, the Graded Faces Test (GFT) and the newly designed Graded Buildings Test (GBT) - were administered to 69 participants (32 patients in the early prodromal stage of AD, so-called Mild Cognitive Impairment (MCI), and 37 normal control participants). Patients were found to be impaired on all three tests compared to controls, although naming of objects was significantly better than naming of faces and buildings. Discriminant analysis successfully predicted group membership for 100% controls and 78.1% of patients. The results suggest that even in cases that do not yet fulfil criteria for AD naming of famous people and buildings is impaired, and that both these semantic domains show greater vulnerability than general semantic knowledge. A semantic deficit together with the hallmark episodic deficit may be common in MCI, and that the use of graded tasks tapping semantic memory may be useful for the early identification of patients with MCI.

Are faces special in Alzheimer's disease? Cognitive conceptualisation, neural correlates, and diagnostic relevance of impaired memory for faces and names

Memory for faces and names has increasingly become a focus of cognitive assessment and research in Alzheimer's disease (AD). This paper reviews evidence from cognitive and clinical neuroscience regarding the question of whether AD is associated with a specific deficit in face recognition, face-name association, and retrieval of semantic information and names. Cognitive approaches conceptualizing face recognition and face-name association have revealed that, compared to other types of visual stimuli, faces are "special" because of their complexity and high intraclass similarity, and because their association with proper names is arbitrary and unique. Neuroimaging has revealed that due to this particular status, face perception requires a complex interplay of highly specialized secondary visual areas located in the occipitotemporal cortex with a widely distributed system of cortical areas subserving further task-dependent processing. Our review of clinical research suggests that AD-related deficits in face recognition are primarily due to mnestic rather than perceptual deficits. Memory for previously studied or famous faces is closely related to mediotemporal and temporocortical brain regions subserving episodic and semantic memory in general, suggesting that AD-related impairments in this domain are due to neural degeneration in these areas. Despite limited specificity due to the apparent absence of a "genuine" domain-specific deficit of face memory in AD, testing memory for faces and names is useful in clinical contexts, as it provides highly sensitive indices of episodic and semantic memory performance. Therefore, clinical assessment of face memory can usefully contribute to early detection of memory deficits in prodromal and initial stages of AD, and represents a basis for further attempts at rehabilitation. Further advantages, such as ecological validity, high task comprehensibility and, in the case of novel face learning, independence from premorbid intelligence level, render measures of face recognition valuable for clinical assessment in early AD.

Proper and common names: a double dissociation

Proper name anomia and proper name sparing are unusual disorders characterized by a selective inability, or sparing, to retrieve proper names as opposed to common names. They may eventually demonstrate that these two categories of names are independently processed in the brain at the semantic or lexical/orthographic level. Yet, differences in patient assessment make comparison between cases difficult to interpret and raise alternative explanations to those dissociations, such as that they may be accounted for by the level of difficulty of test stimuli. We describe two individuals, of identical age, gender and cultural background, with a complementary pattern of impairment of name retrieval following a left hemisphere stroke. ACB had an aphasic disorder with impaired naming, sparing proper names, while JFJ had normal language abilities and semantic knowledge about people, but a marked anomia for people's names. Patients were studied using the same material, thus overcoming methodological constraints pointed to previous work. These cases provide evidence of a double dissociation between proper and common names at the lexical access level. In addition, JFJ had a normal ability to retrieve historical and religious names suggesting that either these names are less difficult to retrieve or that they may segregate within the proper name lexicon. Lesion of the left temporal pole was also dissociated. It was damaged in ACB but spared in JFJ, contradicting its crucial role in proper name processing.

Retrieval pathways for common and proper names

Paradigmatic cases of proper name anomia and proper name selective sparing are reviewed from relevant neuropsychological literature. Available evidence supports the existence of functionally and anatomically distinct retrieval pathways for the categories of proper and common names. An information processing model whose main feature lies in the relative independence within the semantic-conceptual system of information concerning individual entities may account for most of the observed phenomena. Localization studies seem to indicate that a complex neural network sustains various tasks implied in proper name processing. A dedicated module dealing with proper name retrieval is probably there, but its location within the left hemisphere is not at present fully understood. The proper name specific retrieval process is shown, in keeping with current philosophical and linguistic theories, to be intrinsically fragile and source-consuming.

A test for measuring recognition and naming of landmarks

There have been considerable giants in recent years in understanding cognitive and neural correlated for retrieval of various types of knowledge, such as the meanings and lexical forms for categories such as a familiar faces, animals and tools, and actions. An important category that has been largely neglected so far is landmarks, and one likely reason for this is a lack of suitable stimulus materials. Here, we report a study in which we designed a Landmark Recognition and Naming Test. The test contains 65 natural (e.g., "Old Faithful") and artifactual (e.g., "U.S Capitol") landmarks from around the world. Preliminary recognition and naming data about the participants (e.g., educational level, participants, experience traveling to national parks), the stimuli (e.g., visual complexity, image agreement), and participant-stimulus interactions (e.g., familiarity, age of acquisition), and analyzed how such factors influenced landmark recognition and naming. There was a pronounced sex-related difference in landmark recognition favoring men; however, men and women performed similarly in landmark naming. We provide here extensive data regarding the stimuli, and we encourage other investigators to make use of our stimuli and data in future investigations of landmark recognition and naming.

Episodic and semantic memory in mild cognitive impairment

Little is known about episodic and semantic memory in the early predementia stage of Alzheimer's disease (AD), which is referred to as mild cognitive impairment (MCI). To explore person knowledge, item recognition and spatial associative memory, we designed the Face Place Test (FPT). A total of 75 subjects participated: 22 patients with early AD, 24 with MCI and 29 matched controls. As predicted, AD patients showed significant deficits in person naming, item recognition and recall of spatial location (placing). Surprisingly, subjects with MCI were also impaired on all components. There was no significant difference between AD and MCI except on the placing component. Analysis of the relationship between semantic (naming) and episodic (recognition and placing) components of the FPT revealed a significant association between the two episodic tasks, but not between episodic and semantic performance. Patients with MCI show deficits of episodic and semantic memory. The extent of impairment suggests dysfunction beyond the medial temporal lobe. The FPT might form the basis of a sensitive early indicator of AD.