Arithmetic knowledge in semantic dementia: is it invariably preserved?

There is accumulating evidence of preserved arithmetic knowledge in semantic dementia (SD), contrasting with patients' striking impairment in other domains of semantic memory. This important finding exemplifies domain specificity in the breakdown of semantic memory and supports notions of the functional independence of semantic number knowledge. Nevertheless, evidence for preserved arithmetic knowledge in SD comes largely from single case studies. It is not known whether such preservation is a universal finding, or whether it persists irrespective of disease severity. The present study examined performance of 14 SD patients, varying in the severity of their semantic impairment, on tasks assessing knowledge of arithmetic signs, and on single-digit and multi-digit calculation problems, permitting evaluation of fact retrieval and use of procedures. SD patients performed generally well compared to 10 healthy controls on tests of addition and subtraction. However, abnormalities were elicited, which were not explained by education or hemispheric side of atrophy, but increased as a function of semantic severity. Patients had difficulty identifying arithmetic signs. They used increasingly basic, inflexible strategies to retrieve multiplication table 'facts', and in multi-digit calculations they made procedural errors that pointed to a failure to understand the differential weighting of left and right hand columns. The pattern of responses and error types mirrors in reverse that found in children as they acquire arithmetic competence, and suggests a progressive degradation in conceptual understanding of arithmetic. Longitudinal study of two SD patients demonstrated an association between semantic decline and impaired arithmetic performance. The findings challenge the notion of arithmetic knowledge as a totally separate semantic domain and suggest that the temporal lobes play an important role in arithmetic understanding.     

What happens to personal identity when semantic knowledge degrades? A study of the self and autobiographical memory in semantic dementia

While the self has been extensively explored in amnesic patients with severe episodic but not semantic memory disturbance, little is known about the self in semantic dementia (SD), which generally features the reverse pattern of impairment. In the present study, we investigated the structural (self-representations) and functional (consciousness) dimensions of the self in a group of eight SD patients in the early to moderate stages of the disease. We used two original tasks designed to probe both structural characteristics, namely the strength and the certainty of self-concept and the episodic/semantic nature of self-representations, and functional characteristics, namely autonoetic/noetic level of consciousness, self-evaluation and self-projection into the past, present and future. Results for the structural self showed impairment on the semantic aspects of the self-representations, except for those related to the present. Moreover, SD patients were affected regardless of the episodic or semantic nature of self-representations into the future. As regards the functional self, self-projection and level of consciousness were only impaired for the future. This study confirms the persistence of a feeling of identity in SD over time for the past and present selves. However, it also highlights the loss of the future self in SD patients. These results are discussed in relation to models of long-term memory and future thinking focusing on the interplay of episodic and semantic memory and mental time travel.     

Conception or *conceivation? The processing of derivational morphology in semantic dementia

Background: Only a few studies have focused on derivational morphology in semantic dementia (SD). The productive and componential nature of derivational morphology as well as recent findings in psycholinguistics suggest that semantic cognition would be involved in the production and comprehension of derivational morphemes and derived words. Therefore, participants with SD might present impairment in derivational morphology.

Aims: This study aims to specify semantic cognition’s involvement in the production and comprehension of derivational morphemes and morphologically complex words in SD participants. This involvement was considered in relation to the production of morphologically complex words, the comprehension of the meaning conveyed by morphemes, and the capacity to distinguish between words with a real vs. an apparent morphological structure.

Methods and Procedures: Ten French-speaking SD participants completed three tasks of derivational morphology. Their performances were compared to those of a group of 20 age-, gender- and education-matched adults without cognitive impairment.

Outcomes and Results: Compared with participants of the control group, SD participants had more difficulty producing nouns derived from verbs that follow less-frequent patterns of root allomorphy, while their performance was less affected when they could rely on basic morphological decomposition/composition abilities. Participants with SD also had more difficulties to match derived words and pseudo-words to a definition and to distinguish between pairs of real morphological antonyms and pseudo-morphological non-antonyms.

Conclusions: These results support the involvement of semantic cognition in the validation of morpheme combinations and in derivational morpheme representation. Difficulties in the production and comprehension of derived words and derivational morphemes are another of the many consequences of central semantic impairment that characterises SD. More studies are needed to develop tests and further characterise the involvement of semantic cognition in derivational morphology.     

A case of impaired naming and knowledge of body parts. Are limbs a separate sub-category?

A left hemisphere stroke patient presented a disproportionate difficulty for body parts knowledge without autotopagnosia. The deficit concerned the lexical-semantic representation of body parts and was most severe for limbs. The ability to gesture was spared and action naming was not more impaired than object naming. On the basis of normal naming latencies, we conclude that limbs are the most vulnerable component of the overall category of body parts. This vulnerability is not explained by unbalanced nuisance variables. More cognitive effort is probably required for the appropriate differentiation of limbs during semantic processing and lexical access.     

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

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

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

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

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

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

How successful is errorless learning in supporting memory for high and low-level knowledge in dementia?

Errorless learning has been shown to be very successful in the rehabilitation of memory problems particularly in patients with severe forms of memory impairment. Much of this research has focused on testing knowledge of specific details studied, ignoring any additional, higher-level knowledge that patients may have acquired during the learning process. Hence, it is pertinent to ask whether errorless learning is equally successful in the acquisition of high and low-level knowledge. In this paper, we present results of several studies comparing the effectiveness of errorless and standard trial-and-error methods in acquisition of high and low-level knowledge in people diagnosed with dementia and non-impaired controls. In Study 1, participants were asked to learn novel face–name–occupation associations; and knowledge across a range of levels, from very general (i.e., high-level) to very specific (i.e., low-level), was examined. For patients with probable Alzheimer's disease and controls there was evidence of increased benefit from errorless training in general, but the technique was most beneficial for patients attempting to retrieve specific detail. Study 2 was conducted to address the problem raised by the failure in Study 1 to manipulate learning condition at our highest knowledge level. This novel manipulation was successful, but neither of the patients received the standard benefit from errorless training. Study 3, involving a small group of dementia patients with mixed diagnoses, was conducted to replicate findings from Study 1. Results from the group analysis confirmed that the benefit obtained from errorless learning increased as a function of knowledge specificity, but again several patients failed to show a consistent effect of learning condition. Implications for use of the errorless technique are discussed.     

How successful is errorless learning in supporting memory for high and low-level knowledge in dementia?

Errorless learning has been shown to be very successful in the rehabilitation of memory problems particularly in patients with severe forms of memory impairment. Much of this research has focused on testing knowledge of specific details studied, ignoring any additional, higher-level knowledge that patients may have acquired during the learning process. Hence, it is pertinent to ask whether errorless learning is equally successful in the acquisition of high and low-level knowledge. In this paper, we present results of several studies comparing the effectiveness of errorless and standard trial-and-error methods in acquisition of high and low-level knowledge in people diagnosed with dementia and non-impaired controls. In Study 1, participants were asked to learn novel face-name-occupation associations; and knowledge across a range of levels, from very general (i.e., high-level) to very specific (i.e., low-level), was examined. For patients with probable Alzheimer's disease and controls there was evidence of increased benefit from errorless training in general, but the technique was most beneficial for patients attempting to retrieve specific detail. Study 2 was conducted to address the problem raised by the failure in Study 1 to manipulate learning condition at our highest knowledge level. This novel manipulation was successful, but neither of the patients received the standard benefit from errorless training. Study 3, involving a small group of dementia patients with mixed diagnoses, was conducted to replicate findings from Study 1. Results from the group analysis confirmed that the benefit obtained from errorless learning increased as a function of knowledge specificity, but again several patients failed to show a consistent effect of learning condition. Implications for use of the errorless technique are discussed.     

Knowledge of living,nonliving and “sensory quality” categories in semantic dementia

This article reports the findings from 3 patients with semantic dementia (SD) who were given a novel battery of 33 items from sensory quality categories (SQCs) as previously described by Borgo and Shallice (2001 Borgo, F and Shallice, T. 2001. When living things and other "sensory quality" categories behave in the same fashion: A novel category specificity effect. Neurocase, 7: 201–220. [PUBMED][INFOTRIEVE][CSA][CROSSREF][Taylor & Francis Online], [Web of Science ®] , [Google Scholar]; 2003) and Laiacona, Capitani and Caramazza (2003) Laiacona, M, Capitani, E and Caramazza, A. 2003. Category-specific semantic deficits do not reflect the sensory/functional organisation of the brain: A test of the “sensory quality” hypothesis. Neurocase, 9(3): 221–231. [PUBMED][INFOTRIEVE][CSA][CROSSREF][Taylor & Francis Online], [Web of Science ®] , [Google Scholar]. Their performance on three tasks (two naming, one word-to-picture matching) was compared with performance on similar tasks using a conventional semantic battery. At the group level, patients performed worse than age-matched controls overall, but neither group showed any differences in performance between domains (i.e., living, nonliving and SQCs). Individual patient analyses, however, showed contrasting profiles in the three patients. The results are discussed in terms of the SFT (Warrington & Shallice, 1984 Warrington, EK and Shallice, T. 1984. Category specific semantic impairments. Brain, 107: 829–854. [PUBMED][INFOTRIEVE][CSA][Crossref], [PubMed], [Web of Science ®] , [Google Scholar]) and individual differences (Lambon-Ralph et al., 2003) accounts of category-specificity in SD.     

Cerebrospinal fluid amyloid-β 2-42 is decreased in Alzheimer’s, but not in frontotemporal dementia

Alzheimer's dementia (AD) and frontotemporal dementias (FTD) are common and their clinical differential diagnosis may be complicated by overlapping symptoms, which is why biomarkers may have an important role to play. Cerebrospinal fluids (CSF) Aβ2-42 and 1-42 have been shown to be similarly decreased in AD, but 1-42 did not display sufficient specificity for exclusion of other dementias from AD. The objective of the present study was to clarify the diagnostic value of Aβ2-42 peptides for the differential diagnosis of AD from FTD. For this purpose, 20 non-demented disease controls (NDC), 22 patients with AD and 17 with FTD were comparatively analysed by a novel sequential aminoterminally and carboxyterminally specific immunoprecipitation protocol with subsequent Aβ-SDS-PAGE/immunoblot, allowing the quantification of peptides 1-38(ox), 2-40 and 2-42 along with Aβ 1-37, 1-38, 1-39, 1-40, 1-40(ox) and 1-42. CSF Aβ1-42 was decreased in AD as compared to NDC, but not to FTD. In a subgroup of the patients analyzed, the decrease of Abeta2-42 in AD was evident as compared to both NDC and FTD. Aβ1-38 was decreased in FTD as compared to NDC and AD. For differentiating AD from FTD, Aβ1-42 demonstrated sufficient diagnostic accuracies only when combined with Aβ1-38. Aβ2-42 yielded diagnostic accuracies of over 85?% as a single marker. These accuracy figures could be improved by combining Aβ2-42 to Aβ1-38. Aβ2-42 seems to be a promising biomarker for differentiating AD from other degenerative dementias, such as FTD.     

General practitioners’ knowledge,practices, and obstacles in the diagnosis and management of dementia

Objectives: To identify general practitioners’ (GPs) knowledge, practices, and obstacles with regard to the diagnosis and management of dementia.

Methods: Standardized questionnaires covering knowledge, practices, and obstacles were distributed among a purposive sample of GPs in Kathmandu, Nepal. Three hundred and eighty GPs responded (response rate = 89%).

Results: Knowledge of practitioners’ with regard to the diagnosis and management of dementia was unsatisfactory (<50%). Diagnosis and management barriers are presented with regard to GP, patient, and carer factors. Specifically, the results address the following issues: communicating the diagnosis, negative views of dementia, difficulty diagnosing early-stage dementia, acceptability of specialists, responsibility for extra issues, knowledge of dementia and aging, less awareness of declining abilities, diminished resources to handle care, lack of specific guidelines, and poor awareness of epidemiology.

Conclusions: Demographic changes mean that dementia will represent a significant problem in the future. The following paper outlines the problems and solutions that the Nepalese medical community needs to adopt to deal effectively with diagnosis, care, and management of dementia.     

What do we know about dementia?: a survey on knowledge about dementia in the general public of Japan

OBJECTIVE: The importance of early detection of dementia has been highlighted in recent years by the medical and scientific community; however, delays often occur between the recognition of signs or symptoms and a decision by the patient or family to seek professional help. Such delays may be caused by a lack of knowledge about dementia among patients and family members. The aim of this study was to determine the understanding of dementia among the general public. METHODS: We conducted a survey in Japan that asked 11 questions regarding knowledge of 'general' information, 'symptoms', and 'biomedical' issues related to dementia. A quota sampling method was used to select 2,500 participants, 2,115 of who were eligible for the analyses. RESULTS: The average number of correct responses among females was significantly greater than that among the males. A multiple comparisons test demonstrated that middle-aged women were more knowledgeable than younger and older respondents. It was revealed that there was a lack of knowledge on biomedical aspects of dementia, i.e. cause, treatment, and prognosis along with a misunderstanding of dementia as senescence forgetfulness among the general public. CONCLUSIONS: There appeared to be gaps in knowledge on dementia among the general public, which may prevent caregivers from planning upcoming social and financial challenges. Correct information needs to be given by health professionals and care staff. Educational initiatives planned for the general public could be useful, and should target those groups, men and non-middle aged women who have lower knowledge.     

Why do young women diet? The roles of body fat, body perception, and body ideal

BACKGROUND: To assess the relative roles of body fat, body perception, and body ideals as motivations for dieting in college women. METHOD: We compared 45 college women who reported having dieted with 32 who had not, using a novel computerized test of body image called the somatomorphic matrix. RESULTS: As expected, the difference in body fat between subjects' "perceived body" and "ideal body" was significantly greater in dieters than in nondieters (p < .001). Remarkably, however, this difference remained highly significant even after adjusting for the subjects' actual measured body fat (p = .002). Further analysis revealed that this difference persisted, not because dieters had unrealistic ideals of thinness, but because they had distorted perceptions of their fatness. CONCLUSION: Distorted body image perception, a potentially treatable condition, may play an unexpectedly large role in motivating young women to diet.     

What is a suggestion? The neuroscience of implicit processing heuristics in therapeutic hypnosis and psychotherapy

Neuroscience and bioinformatics research on activity-dependent gene expression and brain plasticity in memory and learning are used to reconceptualize a fundamental question of therapeutic hypnosis, "What is a suggestion?" John Kihlstrom's cognitive-behavioral perspective of implicit (unconscious) and explicit (conscious) memory and Eric Kandel's Nobel Prize winning neurobiological research are integrated for a 30-year update of Milton H. Erickson's "neuro-psycho-physiology" of therapeutic hypnosis. Implicit processing heuristics are proposed as a more general framework for Erickson's concept of permissive indirect suggestions in therapeutic hypnosis and psychotherapy. These perspectives are illustrated by utilizing implicit processing heuristics to facilitate the four-stage creative process in converting implicit to explicit memory in a brain-damaged patient.     

Mirror gazing increases attractiveness in satisfied, but not in dissatisfied women: A model for body dysmorphic disorder?

Body dysmorphic disorder is a severe disturbance in which the person is preoccupied with an imagined defect in appearance. It is unclear what causes and what maintains BDD, although it is assumed that patients are characterized by an increased self-focused attention. Since patients spend a lot of time examining their ‘defect’ in reflecting surfaces, it might well be that mirror gazing itself is an important maintaining factor for BDD, as it may lead to a loss of sense of proportions. If so, normal individuals' body evaluations are expected to decrease likewise after mirror exposure. In the present study, 50 female students watched both their own face in the mirror and a photograph of a neutral female face for 3.5 min. Before and after gazing, they rated the attractiveness of the faces. Results indicate that mirror exposure did not lead to decreased attractiveness in normal participants. However, when participants were divided into high and low satisfaction about appearance, highly satisfied individuals' evaluations of their own face improved, whereas low satisfied individuals' evaluations tended to decrease. For the other face, only the low satisfied individuals showed increased attractiveness scores at post-test. The results are explained by selective visual attention and are in line with recent findings in eating disordered women.