Gait analysis in elderly adult patients with mild cognitive impairment and patients with mild Alzheimer’s disease: simple versus dual task: A preliminary report

in Clinical Physiology & Functional Imaging (2010), 30(1), 51-56

Background ⁄ Aims: The aim of this study was to assess gait characteristics during simple and dual task in patients with mild cognitive impairment (MCI) and compare them with those of healthy elderly ... [more ▼]

Background ⁄ Aims: The aim of this study was to assess gait characteristics during simple and dual task in patients with mild cognitive impairment (MCI) and compare them with those of healthy elderly subjects and mild Alzheimer s disease (AD) patients. Methods: We proposed a gait analysis to appreciate walking (simple task and dual task) in 14 MCI, 14 controls and six AD subjects who walked at their preferred speed. A 20-second period of stabilized walking was used to calculated stride frequency, stride length, symmetry and regularity. Speed walking was measured by electrical photocells. Results: Variables measured during simple and dual tasks showed an alteration of motor function as well in mild AD patients as in MCI patients. Conclusion: At the end of this preliminary study, we defined a specific gait pattern for each cognitive profile. Further researches appear necessary to enlarge the study cohort. [less ▲]

Working memory load modulates time-of-day and chronotype effects on task-related BOLD activity

in NeuroImage (2010), 51(Suppl. 1),

Les corrélats cérébraux de la recollection et de la familiarité dans la maladie d'Alzheimer

Conference (2010)

Anosognosia for personality and impaired self-representation in early stages of Alzheimer’s disease

Conference (2010)

An fMRI region-based investigation of cognitive processes involved in the item-method directed forgetting

Conference (2010)

Neural substrates of recollection and familiarity in Alzheimer’s disease

in Proceedings of the 16th annual meeting of the Organization for Human Brain Mapping (2010)

Verbal Learning in Alzheimer’s disease and Mild Cognitive Impairment: neuroanatomic correlates of acquisition and consolidation performances

in Proceedings of the Annual Meeting of the Belgian Association for Psychological Sciences (2010)

The aim of this study was to examine correlations between impaired memory acquisition/consolidation and brain metabolism at rest in Alzheimer’s disease. 44 confirmed Alzheimer patients (AD), 16 patients ... [more ▼]

The aim of this study was to examine correlations between impaired memory acquisition/consolidation and brain metabolism at rest in Alzheimer’s disease. 44 confirmed Alzheimer patients (AD), 16 patients with mild cognitive impairment (MCI) who converted to AD (MCI-C) (4-8 years of follow-up), 15 MCI patients who remained stable and 12 healthy elderly controls were administered the California Verbal Learning Task (CVLT) at entry. Acquisition and consolidation memory scores were calculated respectively as mean gained and total lost access across the 5 study-test trials (p = 0.05). Brain metabolism was measured by 18FDG-PET. Cognitive-metabolic correlations were performed with SPM8 (p<0.05 uncorrected). Mean gained access was significantly lower in the AD group than in the control and MCI-S group and was significantly lower in the MCI-C group than in the control group. Mean gained access was significantly correlated to metabolism in the left precentral gyrus and IPS fondus in the control group, in the left and right inferior parietal lobules in the MCI-S group and in the left hippocampus in the AD group. Total lost access was greater in AD patients compared to control participants. No significant correlation between total lost access and brain metabolism was found. The acquisition process is impaired in AD patients at a very early stage of the disease (MCI-C). This deficit is linked to metabolic changes in a frontoparieto-hippocampal learning network. In addition, consolidation process is specifically impaired in confirmed AD patients, while this deficit was not significantly correlated to brain metabolism in our participant groups. [less ▲]

L’anosognosie dans la maladie d’Alzheimer est-elle observée pour les modifications de comportement et de personnalité?

in Proceedings du XIème Colloque International sur le Vieillissement Cognitif (2010)

Conscience du fonctionnement de la mémoire dans la maladie d’Alzheimer

in Proceedings du XIeme colloque international sur le vieillissement cognitif (2010)

Neural networks involved in self-judgement in young and elderly adults

in NeuroImage (2010)

Recent studies have shown that both young and elderly subjects activate the ventromedial prefrontal cortex (VMPFC) when they make self-referential judgements. However, the VMPFC might interact with ... [more ▼]

Recent studies have shown that both young and elderly subjects activate the ventromedial prefrontal cortex (VMPFC) when they make self-referential judgements. However, the VMPFC might interact with different brain regions during self-referencing in the two groups. In this study, based on data from Ruby et al (2009), we have explored this issue using psychophysiological interaction analyses. Young and elderly participants had to judge adjectives describing personality traits in reference to the self versus a close friend or relative (the other), taking either a first-person or a third-person perspective. The physiological factor was the VMPFC activity observed in all participants during self judgement, and the psychological factor was the self versus other referential process. The main effect of first-person perspective in both groups revealed that the VMPFC was coactivated with the left parahippocampal gyrus and the precuneus for self versus other judgments. The main effect of age showed a stronger correlation between activity in the VMPFC and the lingual gyrus in young compared to elderly subjects. Finally, in the interaction, the VMPFC was specifically co-activated with the orbitofrontal gyrus and the precentral gyrus when elderly subjects took a first-person perspective for self judgements. No significant result was observed for the interaction in young subjects. These findings show that, although the VMPFC is engaged by both young and older adults when making self-referential judgements, this brain structure interacts differently with other brain regions as a function of age and perspective. These differences might reflect a tendency by older people to engage in more emotional/social processing than younger adults when making self-referential judgements with a first-person perspective [less ▲]