Bilingualism has been associated with successful aging. In particular, research on the cognitive advantages of bilingualism suggests that it can enhance control over interference and help delay the onset of dementia signs. However, the evidence on the so-called cognitive advantage is not unanimous; furthermore, little is known about the neural basis of this supposed cognitive advantage in bilingual as opposed to monolingual elderly populations. In this study, elderly bilingual and monolingual participants performed a visuospatial interference control task during functional magnetic resonance imaging (fMRI) scanning. Response times and accuracy rates were calculated for congruent and incongruent conditions of the Simon task, and the neurofunctional correlates of performance on the Simon task were examined. The results showed equivalent performance on the Simon task across groups but different underlying neural substrates in the two groups. With incongruent trials, monolinguals activated the right middle frontal gyrus, whereas bilinguals relied upon the left inferior parietal lobule. These results show that elderly bilinguals and monolinguals have equivalent interference control abilities, but relay on different neural substrates. Thus, while monolinguals show a classical PASA (posterior–anterior shift in aging) effect, recruiting frontal areas, bilinguals activate visuospatial processing alone and thus do not show this posterior–anterior shift. Moreover, a modulation of frontal activity with task-dynamic control of interference, observed in the elderly bilingual group alone, suggests that elderly bilinguals deal with interference control without recruiting a circuit that is particularly vulnerable to aging.

Introduction. Globalization imposes challenges to the field of behavioural neurology, among which is an increase in the prevalence of bilingual aphasia. Thus, aphasiologists have increasingly focused on bilingual aphasia therapy and, more recently, on the identification of the most efficient procedures for triggering language recovery in bilinguals with aphasia. Therapy in both languages is often not available, and, thus, researchers have focused on the transfer of therapy effects from the treated language to the untreated one.Aim. This paper discusses the literature on bilingual aphasia therapy, with a focus on cross-linguistic therapy effects from the language in which therapy is provided to the untreated language.Methods. Fifteen articles including two systematic reviews, providing details on pre- and posttherapy in the adult bilingual population with poststroke aphasia and anomia are discussed with regard to variables that can influence the presence or absence of cross-linguistic transfer of therapy effects.Results and Discussion. The potential for CLT of therapy effects from the treated to the untreated language depends on the word type, the degree of structural overlap between languages, the type of therapy approach, the pre- and postmorbid language proficiency profiles, and the status of the cognitive control circuit.

Leisure activities can be both enjoyable and cognitively stimulating, and participation in such activities has been associated with reduced age-related cognitive decline. Thus, integrating stimulating leisure activities in cognitive training programs may represent a powerful and innovative approach to promote cognition in older adults at risk of dementia. The ENGAGE study is a randomized controlled, double-blind preference trial with a comprehensive cohort design that will test the efficacy and long-term impact of an intervention that combines cognitive training and cognitively stimulating leisure activities. One hundred and forty-four older adults with a memory complaint will be recruited in Montreal and Toronto. A particular effort will be made to reach persons with low cognitive reserve. Participants will be randomly assigned to one of two conditions: cognitive + leisure training (ENGAGE-MUSIC/SPANISH) or active control (ENGAGE-DISCOVERY). The ENGAGE-MUSIC/SPANISH training will include teaching of mnemonic and attentional control strategies, casual videogames selected to train attention, and classes in music or Spanish as a second language. The ENGAGE-DISCOVERY condition will comprise psychoeducation on cognition and the brain, low-stimulating casual videogames and documentary viewing with discussions. To retain the leisure aspect of the activities, participants will be allowed to exclude either music or Spanish at study entry if they strongly dislike one of these activities. Participants randomized to ENGAGE-MUSIC/SPANISH who did not exclude any activity will be assigned to music or Spanish based on a second random assignment. Training will be provided in 24 2-h sessions over 4 months. Outcomes will be measured at baseline, at 4-month follow-up, and at 24-month follow-up. The primary outcome will be cognitive performance on a composite measure of episodic memory (delayed recall scores for words and face-name associations) measured at baseline and at the 4-month follow-up. Secondary outcomes will include a composite measure of attention (speed of processing, inhibition, dual tasking, and shifting), psychological health, activities of daily living, and brain structure and function and long-term maintenance measured at the 24-month follow-up. Information on cognitive reserve proxies (education and lifestyle questionnaires), sex and genotype (apolipoprotein (Apo)E4, brain-derived neurotrophic factor (BDNF), and catechol-O-methyltransferase (COMT)) will be collected and considered as moderators of training efficacy. This study will test whether a program combining cognitive training with stimulating leisure activities can increase cognition and reduce cognitive decline in persons at risk of dementia. NCT03271190 . Registered on 5 September 2017.

Background: Globalization has resulted in a growing bilingual population worldwide; thus, bilingual speakers with aphasia are also increasing. The ability to juggle languages has been reported to enhance attentional control abilities in healthy populations. However, few studies have looked at the impact of bilingualism on attentional control abilities in individuals with aphasia. Different subcomponents of attention are seldom studied in bilingual aphasia. Aims: The goal of the study is to explore the influence of bilingualism on three subcomponents of attention in individuals with aphasia, namely alerting, orienting and executive control. The study aimed to examine whether (1) individuals with aphasia show evidence of an attentional deficit in comparison to language-matched healthy peers, (2) there is evidence of a bilingual advantage in attentional mechanisms, and (3) there is a relationship between bilingualism and subcomponents of attention. Methods and Procedures: All the participants (10 French-English bilingual and 7 French monolingual adults with aphasia and 32 monolingual and bilingual healthy controls) performed a behavioural version of the Attention Network Test. The efficiency of the three attentional networks was assessed by measuring how response times varied with different warning cues and flanker type, resulting in alerting, orienting and executive control effects. Objective and subjective measures of bilingualism were also included. Results: Results confirmed a bilingual advantage in attentional mechanisms with and without aphasia. More specifically, group difference for healthy controls was evident in the accuracy rate only. For individuals with aphasia, between-group comparisons revealed differences in alerting ability: the bilingual group presented a significantly greater difference score than the monolingual group in the mu (μ) component of the response time distribution, whereas the monolingual group was able to take advantage of the alerting cue in the tau (τ) component. Furthermore, the monolingual and bilingual speakers with aphasia exhibited reduced alerting and more interference effect when compared to their respective healthy controls. Conclusions: This study provides evidence that bilingualism impacts attentional mechanisms in individuals with aphasia as well as healthy controls. Specifically, bilingual individuals with aphasia showed more efficient alerting skills than monolinguals with aphasia. Ex-Gaussian data analysis revealed effects that might otherwise be thought to be non-existent. Considering the growing bilingual population, an understanding of the behavioural signs and symptoms of attentional abilities in individuals with aphasia is necessary for both theoretical and clinical purposes.

Studies show bilingualism entails an advantage in cognitive control tasks. There is evidence of a bilingual advantage in the context of aphasia, resulting in better cognitive outcomes and recovery in bilingual persons with aphasia compared to monolingual peers. This bilingual advantage also results in structural changes in the right hemisphere gray matter. Very few studies have examined the so-called bilingual advantage by reference to specific anomia therapy efficacy. This study aims to compare the effect of French-Phonological Component Analysis (Fr-PCA) in monolinguals and bilingual persons with aphasia, both at the linguistic and cognitive control level, and to examine the structural impact of left hemisphere lesion location and right hemisphere structural data. Eight participants with chronic aphasia received Fr-PCA for a total of 15 h over 5 weeks. The results showed improved accuracy for treated words and generalization to untreated items and discourse in both groups, and improved Flanker task performance for some participants. Bilingual participants improved more than monolinguals for picture-naming tasks and narrative discourse. Damage to the left postcentral gyrus and the middle frontal gyrus was associated with less therapy-induced improvement. Additionally, left hemisphere damage to the inferior parietal gyrus and postcentral gyrus was associated with reduced cognitive control pre-therapy. Undamaged right hemisphere cortical thicknesses were significantly different between groups; the inferior frontal gyrus and the middle frontal gyrus were greater for the bilingual participants and correlated with cognitive control skills. These results suggest a bilingual advantage in anomia recovery following Fr-PCA, potentially resulting from enhanced cognitive control abilities that could be supported by right hemisphere neural reserve.

There is evidence that the explicit lexical-semantic processing deficits which characterize aphasia may be observed in the absence of implicit semantic impairment. The aim of this article was to critically review the international literature on lexical-semantic processing in aphasia, as tested through the semantic priming paradigm. Specifically, this review focused on aphasia and lexical-semantic processing, the methodological strengths and weaknesses of the semantic paradigms used, and recent evidence from neuroimaging studies on lexical-semantic processing. Furthermore, evidence on dissociations between implicit and explicit lexical-semantic processing reported in the literature will be discussed and interpreted by referring to functional neuroimaging evidence from healthy populations. There is evidence that semantic priming effects can be found both in fluent and in non-fluent aphasias, and that these effects are related to an extensive network which includes the temporal lobe, the pre-frontal cortex, the left frontal gyrus, the left temporal gyrus and the cingulated cortex.