Cognitive reserve (CR) is a potential mechanism to cope with brain damage. The aim of this study was to evaluate the effect of cognitive reserve on a cognitive training (CT) in a group of patients with dementia. 86 participants with mild to moderate dementia were identified by their level of CR quantified by the Cognitive Reserve Index questionnaire (CRIq) and underwent a cycle of CT. A global measure of cognition (MMSE) was obtained before (T0) and after (T1) the training. Multiple linear regression analyses highlighted CR as a significant factor able to predict changes in cognitive performance after the CT. In particular, patients with lower CR benefited from a CT program more than those with high CR. These data show that CR can modulate the outcome of a CT program and that it should be considered as a predictive factor of neuropsychological rehabilitation training efficacy in people with dementia.

Retrieving information from long-term memory can result in the episodic forgetting of related material. One influential account states that this retrieval-induced forgetting (RIF) phenomenon reflects inhibitory mechanisms called into play to decrease retrieval competition. Recent neuroimaging studies suggested that the prefrontal cortex, which is critically engaged in inhibitory processing, is also involved in retrieval competition situations. Here, we used transcranial direct current stimulation (tDCS) to address whether inhibitory processes could be causally linked to RIF. tDCS was administered over the right dorsolateral prefrontal cortex during the retrieval-practice phase in a standard retrieval-practice paradigm. Sixty human participants were randomly assigned to anodal, cathodal, or sham-control groups. The groups showed comparable benefits for practiced items. In contrast, unlike both the sham and anodal groups, the cathodal group exhibited no RIF. This pattern is interpreted as evidence for a causal role of inhibitory mechanisms in episodic retrieval and forgetting.

The objective of this study was to seek evidence of the particular sensitivity of proper name retrieval and to check the usefulness of proper names as diagnostic material in the early stages of Alzheimer's disease (AD). Whether a generalized naming deficit is an early symptom of AD it is not yet clear. Previous studies suggest that proper names might be the category of names that is indeed more sensitive to AD. Seventy AD patients (subdivided into "very mild", "mild" and "moderate") and 47 control subjects participated in the study. The performances in two short distinct tests requiring proper name retrieval (Naming People on Definition and Naming Faces), one test of common name retrieval, short (MMSE, 3MS) and long (MODA) batteries for the detection of dementia were compared. Proper name retrieval tests were shown to be more sensitive to early AD than any other tests and batteries that failed to distinguish "very mild" AD from controls. These findings suggest that proper name retrieval tasks might be profitably included in diagnostic tools for the early diagnosis of AD.