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In the behavioral variant of frontotemporal dementia (bvFTD) memory deficits have been traditionally considered as due to difficulties in encoding/retrieval frontal strategies. However, the frontal origin of memory deficits in bvFTD has been questioned and hippocampal dysfunction has been also proposed. Here we analyzed bvFTD patients' proficiency in subjectively organizing memories without an external criterion. Twenty bvFTD patients and 20 healthy individuals were assessed with memory and executive tasks. The ability to subjectively organize memories in the immediate recall of a 15 unrelated word list was measured by calculating the index of subjective clustering (ISC) based on the constancies in response order across the five consecutive free recall trials. Results revealed reduced ISC in bvFTD patients with respect to normal controls. In the bvFTD group, the ISC score correlated with the Corsi span backward score and the number of categories achieved on the Modified Card Sorting Test. The bvFTD patients' reduced ISC and its correlation with executive performance suggest that executive deficits underlie their defective strategic organization of memories. However, as ISC did not predict memory accuracy in these patients, the memory deficit may not be the mere expression of their executive difficulties. [ABSTRACT FROM AUTHOR]

New technologies show promise in the construction of self-administered home-based programs for targeting language impairments, in overcoming mobility problems and in providing access to care in a cost-effective and time-saving way. In the present study, we investigated the feasibility and effectiveness of a self-administered home-based program for treating word-finding difficulties in persons with Alzheimer's disease. Ten participants practised word repetition training on a smart tablet for two weeks. Two slightly different training conditions were adopted; they varied as to the order of the presentation of the word to be repeated and the corresponding picture. Both training modalities proved effective in improving naming accuracy on the treated items. There were hints of greater treatment efficacy when the picture was presented before the word to be repeated. Furthermore, when the trial started with the word, the degree of general cognitive impairment and lexical semantic deficits correlated with the effect size of the training benefit. By contrast, the picture first training did not have this modulatory effect. Finally, no generalisation to untreated items was observed in naming accuracy, but was detectable with a more sensitive stem completion task. Our study provides compelling evidence in favour of the feasibility and efficacy of a homebased program for remediating anomia in AD. [ABSTRACT FROM AUTHOR]

There is now a large body of evidence suggesting that color and photographic detail exert an effect on recognition of visually presented familiar objects. However, an unresolved issue is whether these factors act at the visual, the semantic or lexical level of the recognition process. In the present study, we investigated this issue by having Alzheimer's patients and normal controls name figures in four presentation displays (PDs): black and white and colored line drawings, and black and white and color photographs. We also collected image agreement (IA) values (a measure of the extent to which the presented figure matches the stored structural description of the depicted object) for the same stimuli and compared the effects of PD on IA and naming accuracy. Our results suggest that color acts on naming by assisting semantic processing of the stimuli to be recognized; by contrast, photographic detail seems to benefit visual processing by increasing IA. (Contains 2 figures.)

A category-specific naming effect penalizing living things has often been reported in patients suffering from Alzheimer's disease (AD) and in other brain damaged populations, while the opposite dissociation (i.e., lower accuracy in naming nonliving than living things) is much rarer. In this study, we investigated whether the use of line drawings (rather than color photographs) in picture-naming tasks could be a relevant factor in the emergence of a category effect penalizing living things and found evidence in favor of this hypothesis. We administered the same naming tasks comprising living and nonliving items to 10 subjects suffering from AD and 10 normal controls. Once the stimuli were line drawings and once color photographs. A reliable Group x Semantic domain interaction, indicating a disproportionate impairment for living things in the AD group, was only found when line drawings were presented. Results are discussed with reference to two competing approaches to category-specificity in brain damaged people. One assumes that category effects are due to the differential involvement of dedicated neural subsystems, the other emphasizes the role of cross domains imbalances in processing demands. We conclude that our findings lead support to the latter approach. (Contains 2 figures and 3 tables.)

Background: Current theories assume that retrograde memory deficits for semantic information in amnestic mild cognitive impairment (aMCI) are temporally graded and partially sparing most remote memories. Moreover, these models assume a prevalent role of the hippocampus in early phases of memory consolidation and of the prefrontal mesial neocortical areas in permanent consolidation of traces. Purpose: To explore the relationship between hippocampus and memory accuracy for the most recent public events and between the ventro‐medial prefrontal cortex (vmPFC) and memory accuracy irrespective of the memory age, we investigated in aMCI patients the retrograde memory for public events and its relationship with grey matter volume reductions in the hippocampus and vmPFC. Methods: 18 aMCI patients and 13 healthy subjects (HS) underwent a modified version of the Famous Events questionnaire (FEq) to assess their memory performance for public events. Patients underwent 3T‐MRI scanning to assess correlations between FEq's scores and grey matter volumes. Results: aMCI showed significantly reduced performances on FEq compared to HS in the recollection of most recent events, while no significant difference was observed for more remote memories, thus demonstrating a temporal gradient. Moreover, hippocampal volumes predicted accuracy scores for most recent, but not older, public events. Finally, an area in the subcallosal portion of the vmPFC, corresponding to BA32, predicted accuracy scores on FEq irrespective of the period examined. Conclusions: Pathological changes in a neural circuit linking hippocampal to medial prefrontal cortical regions are responsible for impaired recollection of retrograde memories in aMCI. [ABSTRACT FROM AUTHOR]