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Background: Vascular risk factors such as arterial stiffness play an important role in the etiology of Alzheimer’s disease (AD), presumably due to the emergence of white matter lesions. However, the impact of arterial stiffness to white matter structure involved in the etiology of AD, including the corpus callosum remains poorly understood. Objective: The aims of the study are to better understand the relationship between arterial stiffness, white matter microstructure, and perfusion of the corpus callosum in older adults. Methods: Arterial stiffness was estimated using the gold standard measure of carotid-femoral pulse wave velocity (cfPWV). Cognitive performance was evaluated with the Trail Making Test part B-A. Neurite orientation dispersion and density imaging was used to obtain microstructural information such as neurite density and extracellular water diffusion. The cerebral blood flow was estimated using arterial spin labelling. Results: cfPWV better predicts the microstructural integrity of the corpus callosum when compared with other index of vascular aging (the augmentation index, the systolic blood pressure, and the pulse pressure). In particular, significant associations were found between the cfPWV, an alteration of the extracellular water diffusion, and a neuronal density increase in the body of the corpus callosum which was also correlated with the performance in cognitive flexibility. Conclusion: Our results suggest that arterial stiffness is associated with an alteration of brain integrity which impacts cognitive function in older adults.

This study examined the additive versus synergistic contribution of beta-amyloid (Aβ) and white matter hyperintensities (WMHs) across 7 cognitive domains in 104 cognitively normal older adults. It also measured the extent to which age-related differences in cognition are driven by measurable brain pathology. All participants underwent neuropsychological assessment along with magnetic resonance imaging and Pittsburg compound B-positron emission tomography imaging for Aβ quantification. WMH severity was quantified using the age-related white matter changes scale. Stepwise regressions, moderation, and mediation modeling were performed. Our findings show that Aβ deposition single-handedly predicts poorer episodic memory performance and that Aβ and WMHs contribute additively to poorer performance in working memory and language while carrying synergistic associations with executive functions and attention. Through mediation modeling, we demonstrated that the influence of age over episodic memory, working memory, executive functions, and language is fully mediated by brain pathology. This study permits to conclude that, in healthy older adults, (1) Aβ burden and WMHs have synergistic associations with some cognitive domains and (2) age-related differences in most cognitive domains are driven by brain pathology associated with dementia.

IntroductionAssessment of decision-making capacity (DMC) is essential in daily life as well as for defining a person-centred care plan. Nevertheless, in ageing, especially if signs of dementia appear, it becomes difficult to assess decision-making ability and raises ethical questions. Currently, the assessment of DMC is based on the clinician’s evaluation, completed by neuropsychological tests. Functional MRI (fMRI) could bring added value to the diagnosis of DMC in difficult situations.Methods and analysisIMAGISION is a prospective, monocentric, single-arm study evaluating fMRI compared with clinical assessment of DMC. The study will begin during Fall 2021 and should be completed by Spring 2023. Participants will be recruited from a memory clinic where they will come for an assessment of their cognitive abilities due to decision-making needs to support ageing in place. They will be older people over 70 years of age, living at home, presenting with a diagnosis of mild dementia, and no exclusion criteria of MRI. They will be clinically assessed by a geriatrician on their DMC, based on the neuropsychological tests usually performed. Participants will then perform a behavioural task in fMRI (Balloon Analogue Risk Task) to analyse the activation areas. Additional semistructured interviews will be conducted to explore real life implications. The main analysis will study concordance/discordance between the clinical classification and the activation of fMRI regions of interest. Reclassification as ‘capable’, based on fMRI, of patients for whom clinical diagnosis is ‘questionable’ will be considered as a diagnostic gain.Ethics and disseminationIMAGISION has been authorised by a research ethics board (Comité de Protection des Personnes, Bordeaux, II) in France, in accordance with French legislation on interventional biomedical research, under the reference IDRCB number 2019-A00863-54, since 30 September 2020. Participants will sign an informed consent form. The results of the study will be presented in international peer-reviewed scientific journals, international scientific conferences and public lectures.Trial registration numberNCT03931148

Decision making is a complex cognitive phenomenon commonly used in everyday life. Studies have shown differences in behavioral strategies in risky decision-making tasks over the course of aging. The development of functional neuroimaging has gradually allowed the exploration of the neurofunctional bases of these behaviors. The purpose of our study was to carry out a meta-analysis on the neural networks underlying risky decision making in healthy older adults. Following the PRISMA guidelines, we systematically searched for fMRI studies of decision making in older adults using risky decision-making tasks. To perform the quantitative meta-analysis, we used the revised version of the activation likelihood estimation (ALE) algorithm. A total of 620 references were selected for initial screening. Among these, five studies with a total of 98 cognitively normal older participants (mean age: 69.5 years) were included. The meta-analysis yielded two clusters. Main activations were found in the right insula, bilateral dorsolateral prefrontal cortex (dlPFC) and left orbitofrontal cortex (OFC). Despite the limited number of studies included, our meta-analysis highlights the crucial involvement of circuits associated with both emotion regulation and the decision to act. However, in contrast to the literature on young adults, our results indicate a different pattern of hemispheric lateralization in older participants. These activations can be used as a minimum pattern of activation in the risky decision-making tasks of healthy older subjects.

International audience; Introduction: Accumulating evidence over the past decade suggests that semantic deficits represent a consistent feature of Mild Cognitive Impairment (MCI). A meta-analysis was performed to examine if semantic deficits are consistently found in patients with MCI. Methods: Studies meeting all inclusion criteria were selected for the current meta-analysis. An effect size and a weight were calculated for each study. A random effect model was performed to assess the overall difference in semantic performances between MCI patients and healthy subjects. Results: 22 studies (476 healthy participants, 476 MCI patients, mean MMSE of the MCI patients: 27.05 ± 0.58) were included in the meta-analysis. Results indicate that MCI patients systematically performed significantly worse than healthy matched controls in terms of overall semantic performance (mean effect size of 1.02; 95% CI [0.80; 1.24]). Discussion: Semantic deficits are a key feature of MCI. Semantic tests should be incorporated in routine clinical assessments.

Despite a well-documented pattern of semantic memory (SM) impairment, the patterns of brain activation during semantic processing in svPPA still remain poorly understood. The current study aimed to investigate the neural substrates of residual semantic processing in the context of this significant but selective SM impairment, through the case study of one svPPA patient. One svPPA patient (EC) and six elderly controls carried out a general-level semantic categorization task (biological and manufactured objects) while their brain activity was recorded using magnetoencephalography (MEG). Despite similar behavioral performance, EC showed hyperactivation of the left inferior temporal gyrus (ITG) and right anterior temporal lobe (ATL) relative to controls. This suggests that periatrophic regions within the ATL region may support preserved semantic abilities in svPPA. These results thus contribute to our understanding of the brain regions which are recruited to compensate for bilateral atrophy of the ATL and ensure residual semantic processing in svPPA.

Introduction The Verbal Fluency Test (VF) is commonly used in neuropsychology. Some studies have demonstrated a marked impairment of semantic VF compared to phonemic VF in Alzheimer’s disease (AD). Since amnestic Mild Cognitive Impairment (aMCI) is associated with increased risk of conversion to incident AD, it is relevant to examine whether a similar impairment is observed in this population. The objective of the present empirical study is to compare VF performance of aMCI patients to those of AD and elderly controls matched one-to-one for age and education. Method Ninety-six participants divided into three equal groups (N = 32: AD, aMCI and Controls) were included in this study. Participants in each group were, on average, 76 years of age and had 13 years of education. A repeated measures ANOVA with the Group (AD, aMCI, NC) as between-subject factor and the Fluency condition (“P” and “animals”) as within-subject factor was performed. T-tests and simple ANOVAs were also conducted to examine the interaction. Results There was a significant interaction between the groups and the verbal fluency condition. In AD, significantly fewer words were produced in both conditions. In contrast, participants with aMCI demonstrated a pattern similar to controls in the phonemic condition, but generated significantly fewer words in the semantic condition. Conclusion These results indicate a semantic memory impairment in aMCI revealed by a simple, commonly-used neuropsychological test. Future studies are needed to investigate if semantic fluency deficits can help predict future conversion to AD.

Prospective memory (PM) problems in aging and, to a greater extent, in mild cognitive impairment (MCI), compromise functional independence. This study examined the effectiveness of a cognitive training program based on visual imagery to improve PM among older adults with and without MCI. Participants were older adults, 24 with MCI and 24 cognitively healthy (HOA). Half of them (12 MCI and 12 HOA) were randomly assigned to the PM training program, the other half to the no-training control group. All participants also completed a pre- and post-test evaluation, including neuropsychological tests, questionnaires, and the Ecological Test of Prospective Memory (TEMP). There was no significant effect of the intervention on the TEMP total, event-based or time-based scores for either the MCI or HOA groups. However, the trained MCI group committed fewer false alarms (i.e., more efficient identification of prospective cues) in the event-based condition of the TEMP at post-test. On the other hand, all trained participants performed better than control participants on retrospective memory tests, which suggests that visual imagery-based training is more effective to improve retrospective memory than PM. Possible explanations for these results are explored.

Traumatic brain injury (TBI) is increasingly recognized as a major risk factor for developing neurocognitive disorders, though this association remains controversial. Determination of risk factors for post-traumatic neurodegeneration in patients with TBI is critical given the high incidence of TBI. We hypothesized that cardiovascular and metabolic comorbidities, in addition to TBI severity, are associated with the risk of post-traumatic development of Alzheimer disease dementia (ADD). A case-controlled retrospective study was conducted using medical records and medical insurance data of 5642 patients with TBI admitted to a tertiary trauma center over a 12-year period, to assess risk factors of developing ADD after TBI. Logistic regression shows that presence of post-traumatic amnesia ( P= 0.03) and chronic vascular lesions ( P= 0.04) are significantly associated with development of ADD after TBI. This innovative preliminary study is the first to explore risk factors for post-traumatic ADD. Further association studies are essential to optimize care following TBI.

Research involving the general population of people who use a spoken language to communicate has demonstrated that older adults experience cognitive and physical changes associated with aging. Notwithstanding the differences in the cognitive processes involved in sign and spoken languages, it is possible that aging can also affect cognitive processing in deaf signers. This research aims to explore the impact of aging on spatial abilities among sign language users. Results showed that younger signers were more accurate than older signers on all spatial tasks. Therefore, the age-related impact on spatial abilities found in the older hearing population can be generalized to the population of signers. Potential implications for sign language production and comprehension are discussed.

The current study explored whether education, a proxy of cognitive reserve, modifies the association between episodic memory (EM) performance and βeta-amyloid load (Aβ), a biomarker of Alzheimer’s disease, in a cohort of cognitively normal older adults. One hundred and four participants (mean age 73.3 years) evenly spread out in three bands of education were recruited. Participants underwent neuropsychological assessment, structural MRI as well as PET imaging to quantify Aβ load. Moderation analyses and the Johnson–Neyman technique were carried out to examine the interaction of education with Aβ load to predict EM performance. Linear regressions were then performed within each group of education to better illustrate the interaction effect (all analyses were controlled for age and sex). The interaction between education and Aβ load was significant (p < .05) for years of education, reaching a cutoff point of 13.5 years, above which the relationship between Aβ load and EM was no longer significant. Similarly, significant associations were found between Aβ and EM among participants with secondary (p < .01) and pre-university education (p < .01), but not with a university degree (p = .253). EM performance is associated with Aβ load in cognitively normal older individuals, and this relationship is moderated by educational attainment.

The objective of this study was to explore the exact nature, extent, and cognitive correlates of prospective memory deficits in mild cognitive impairment (MCI) by using the Ecological Test of Prospective Memory (TEMP). Twenty-five MCI participants and 25 healthy older adults (HOA) performed the TEMP, the Envelope Task, the Comprehensive Assessment of Prospective Memory (CAPM), and a neuropsychological test battery. Results showed that, during the TEMP, MCI participants had difficulty detecting the moment to perform the intentions in the time-based condition (prospective component) and retrieving the associated actions in the event- and time-based conditions (retrospective component). The prospective component of the event-based condition was correlated with retrospective memory, whereas the prospective component of the time-based condition was correlated with executive functions. Finally, the TEMP yielded good sensitivity and specificity for discriminating between MCI and HOA, contrary to the Envelope Task and the CAPM.

Background Age-related vision impairments and dementia both become more prevalent with increasing age. Research into the mechanisms of these conditions has proposed that some of their causes (eg, macular degeneration/glaucoma and Alzheimer’s disease) could be symptoms of an underlying common cause. Research into sensory-cognitive aging has provided data that sensory decline may be linked to the progression of dementia through reduced sensory stimulation. While hearing loss rehabilitation may have a beneficial effect on cognitive functioning, there are no data available on whether low vision rehabilitation, specifically for reading, could have a beneficial effect on cognitive health. Objective The research questions are: (1) Does low vision rehabilitation reduce reading effort? (2) If so, does reduced reading effort increase reading activity, and (3) If so, does increased reading activity improve cognitive functioning? The primary objective is to evaluate cognition before, as well as at 6 months and 12 months after, 3 weeks of low vision reading rehabilitation using magnification in individuals with age-related macular degeneration, with or without coexisting hearing impairments. We hypothesize that improvements postrehab will be observed at 6 months and maintained at 12 months for participants with vision loss and less so for those with dual sensory loss. The secondary objective is to correlate participant characteristics with all cognitive outcomes to identify which may play an important role in reading rehabilitation. Methods We employ a quasiexperimental approach (nonrandomized, pre-post intervention study). A 3x3 design (3 groups x 3 time points) allows us to examine whether cognitive performance will change before and after 6 months and 12 months of a low vision reading intervention, when comparing 75 low vision and 75 dual sensory impaired (vision & hearing) participants to 75 age-matched healthy controls. The study includes outcome measures of vision (eg, reading acuity and speed), cognition (eg, short-term and long-term memory, processing speed), participant descriptors, demographics, and clinical data (eg, speech perception in noise, mental health). Results The study has received approval, and recruitment began on April 24, 2019. As of March 4, 2021, 38 low vision and 7 control participants have been enrolled. Lockdown forced a pause in recruitment, which will recommence once the COVID-19 crisis has reached a point where face-to-face data collection with older adults becomes feasible again. Conclusions Evidence of protective effects caused by reading rehabilitation will have a considerable impact on the vision rehabilitation community and their clients as well as all professionals involved in the care of older adults with or without dementia. If we demonstrate that reading rehabilitation has a beneficial effect on cognition, the demand for rehabilitation services will increase, potentially preventing cognitive decline across groups of older adults at risk of developing macular degeneration. Trial Registration ClinicalTrials.gov NCT04276610; Unique Protocol ID: CRIR-1284-1217; https://clinicaltrials.gov/ct2/show/NCT04276610 International Registered Report Identifier (IRRID) DERR1-10.2196/19931

BACKGROUND Age-related vision impairments and dementia both become more prevalent with increasing age. Research into the mechanisms of these conditions has proposed that some of their causes (eg, macular degeneration/glaucoma and Alzheimer’s disease) could be symptoms of an underlying common cause. Research into sensory-cognitive aging has provided data that sensory decline may be linked to the progression of dementia through reduced sensory stimulation. While hearing loss rehabilitation may have a beneficial effect on cognitive functioning, there are no data available on whether low vision rehabilitation, specifically for reading, could have a beneficial effect on cognitive health. OBJECTIVE The research questions are: (1) Does low vision rehabilitation reduce reading effort? (2) If so, does reduced reading effort increase reading activity, and (3) If so, does increased reading activity improve cognitive functioning? The primary objective is to evaluate cognition before, as well as at 6 months and 12 months after, 3 weeks of low vision reading rehabilitation using magnification in individuals with age-related macular degeneration, with or without coexisting hearing impairments. We hypothesize that improvements postrehab will be observed at 6 months and maintained at 12 months for participants with vision loss and less so for those with dual sensory loss. The secondary objective is to correlate participant characteristics with all cognitive outcomes to identify which may play an important role in reading rehabilitation. METHODS We employ a quasiexperimental approach (nonrandomized, pre-post intervention study). A 3x3 design (3 groups x 3 time points) allows us to examine whether cognitive performance will change before and after 6 months and 12 months of a low vision reading intervention, when comparing 75 low vision and 75 dual sensory impaired (vision & hearing) participants to 75 age-matched healthy controls. The study includes outcome measures of vision (eg, reading acuity and speed), cognition (eg, short-term and long-term memory, processing speed), participant descriptors, demographics, and clinical data (eg, speech perception in noise, mental health). RESULTS The study has received approval, and recruitment began on April 24, 2019. As of March 4, 2021, 38 low vision and 7 control participants have been enrolled. Lockdown forced a pause in recruitment, which will recommence once the COVID-19 crisis has reached a point where face-to-face data collection with older adults becomes feasible again. CONCLUSIONS Evidence of protective effects caused by reading rehabilitation will have a considerable impact on the vision rehabilitation community and their clients as well as all professionals involved in the care of older adults with or without dementia. If we demonstrate that reading rehabilitation has a beneficial effect on cognition, the demand for rehabilitation services will increase, potentially preventing cognitive decline across groups of older adults at risk of developing macular degeneration. CLINICALTRIAL ClinicalTrials.gov NCT04276610; Unique Protocol ID: CRIR-1284-1217; https://clinicaltrials.gov/ct2/show/NCT04276610 INTERNATIONAL REGISTERED REPORT DERR1-10.2196/19931

Accumulating evidence over the past decade suggests that semantic deficits represent a consistent feature of Mild Cognitive Impairment (MCI). A meta-analysis was performed to examine if semantic deficits are consistently found in patients with MCI. Studies meeting all inclusion criteria were selected for the current meta-analysis. An effect size and a weight were calculated for each study. A random effect model was performed to assess the overall difference in semantic performances between MCI patients and healthy subjects. 22 studies (476 healthy participants, 476 MCI patients, mean Mini Mental Status Examination of the MCI patients: 27.05 ± 0.58) were included in the meta-analysis. Results indicate that MCI patients systematically performed significantly worse than healthy matched controls in terms of overall semantic performance (mean effect size of 1.02; 95% CI [0.80; 1.24]). Semantic deficits are a key feature of MCI. Semantic tests should be incorporated in routine clinical assessments.

The Trail Making Test (TMT) is mainly used to assess visual scanning/processing speed (part A) and executive functions (part B). The test has proven sensitive at detecting cognitive impairment during aging. However, previous studies have shown differences between normative data from different countries and cultures, even when corrected for age and education. Such inconsistencies between normative data may lead to serious diagnostic errors, thus, the development of local norms is warranted. The purpose of this study was to provide regression-based normative data for TMT-A and -B, tailored for a large sample of French-speaking adults from Quebec (Canada).The normative sample consisted of 792 participants aged 50-91 years. Based on multiple linear regression, equations to calculate Z-scores were provided for TMT-A and -B, and for a contrast score which compared performance between TMT-A and -B. Percentiles, stratified by age, are presented for the number of recorded errors.Age was a significant predictor for TMT-A performance, while age and education were independently associated with performance on TMT-B. Gender did not have any effect on performance, in either condition. Education was the only significant predictor of the contrast score between TMT-B and TMT-A. Examiners should remain vigilant when two or more errors are recorded on the TMT-B since this was uncommon in the normative sample.Our TMT normative data improve the accurate detection of visual scanning/processing speed and executive function deficits in Quebec (Canada) French-speaking adults.

ObjectiveTo investigate cortical and subcortical gray matter abnormalities underlying cognitive impairment in patients with REM sleep behavior disorder (RBD) with or without mild cognitive impairment (MCI).MethodsFifty-two patients with RBD, including 17 patients with MCI, were recruited and compared to 41 controls. All participants underwent extensive clinical assessments, neuropsychological examination, and 3-tesla MRI acquisition of T1 anatomical images. Vertex-based cortical analyses of volume, thickness, and surface area were performed to investigate cortical abnormalities between groups, whereas vertex-based shape analysis was performed to investigate subcortical structure surfaces. Correlations were performed to investigate associations between cortical and subcortical metrics, cognitive domains, and other markers of neurodegeneration (color discrimination, olfaction, and autonomic measures).ResultsPatients with MCI had cortical thinning in the frontal, cingulate, temporal, and occipital cortices, and abnormal surface contraction in the lenticular nucleus and thalamus. Patients without MCI had cortical thinning restricted to the frontal cortex. Lower patient performance in cognitive domains was associated with cortical and subcortical abnormalities. Moreover, impaired performance on olfaction, color discrimination, and autonomic measures was associated with thinning in the occipital lobe.ConclusionsCortical and subcortical gray matter abnormalities are associated with cognitive status in patients with RBD, with more extensive patterns in patients with MCI. Our results highlight the importance of distinguishing between subgroups of patients with RBD according to cognitive status in order to better understand the neurodegenerative process in this population.

The ability to execute delayed intentions, known as prospective memory (PM), is crucial to everyday living. PM failures are reported in mild cognitive impairment (MCI) and Parkinson's disease, however, no study to date has investigated PM functioning in individuals at high risk of developing these conditions, precisely those diagnosed with idiopathic REM sleep behavior disorder (iRBD). We aimed to assess PM in iRBD according to patients' cognitive status and to determine the underlying nature of their difficulties.Fifty-eight participants, including 20 healthy controls (HC) and 38 polysomnographic-confirmed iRBD patients with (iRBD-MCI = 13) or without (iRBD-nMCI = 25) MCI participated in this study. Following a neuropsychological assessment, PM was evaluated using a self-administered questionnaire (PRMQ), a simple clinical measure (envelope test), and a laboratory cue salience task.No significant group differences were noted on the PRMQ and envelope test. On the PM laboratory task, non-parametric analyses revealed better detection accuracy in HC than both iRBD groups for all high and low salient cues. While iRBD-nMCI and iRBD-MCI patients performed similarly on the high salient condition, the latter showed significant difficulty in detecting low salient cues. Multiple regression analyses revealed executive dysfunction as the best predictor to significantly account for differences in the low salient condition in iRBD.PM difficulties in iRBD are most important in patients with MCI (vs without MCI) and may be attributed to a gradual alteration in executive mechanisms. PM impairment could act as a promising indicator of early cognitive dysfunction in iRBD.

Objective: The aim of this study was to establish normative data for the Rey Auditory Verbal Learning Test, a test assessing verbal episodic memory, in the older French-Quebec population. Method: A total of 432 French-speaking participants aged between 55 and 93 years old, from the Province of Quebec (Canada), were included in the study. Using multiple regression analyses, normative data were developed for five variable of interest, namely scores on trial 1, sum of trials 1 to 5, interference list B, immediate recall of list A, and delayed recall of list A. Results: Results showed that age, education, and sex were associated with performance on all variables. Equations to calculate the expected score for a participant based on sex, age, and education level as well as the Z score were developed. Conclusion: This study provides clinicians with normative data that take into account the participants’ sociodemographic characteristics, thus giving a more accurate interpretation of the results.

L’Échelle de Dénomination de Boston (BNT) est un des tests neuropsychologiques les plus utilisés pour évaluer les capacités de dénomination d’images, en particulier lors du dépistage de démences. À partir de la version originale (60 items), une version abrégée à 30 items (BNT-30) a été élaborée. La présente étude a analysé les réponses produites par 286 participants québécois francophones âgés entre 50 et 93 ans afin d’établir des normes pour cette version abrégée. Les résultats montrent que la performance au BNT-30 est liée à l’âge et au niveau d’éducation. Des consignes d’administration détaillées sont proposées afin d’uniformiser la passation et la cotation du BNT-30.

Can Alzheimer's disease (AD) patients efficiently learn to perform a complex motor skill when relying on procedural knowledge? To address this question, the authors compared the golf-putting performance of AD patients, older adults, and younger adults in 2 different learning situations: one that promotes high error rates (thus increasing the reliance on declarative knowledge) or one that promotes low error rates (thus increasing the reliance on procedural knowledge). Motor performance was poorer overall for AD patients and older adults relative to younger adults in the high-error condition but equivalent between similar groups in the low-error condition. Also, AD patients in the low-error condition had better performance at the final putting distance relative to those in the high-error condition. This performance facilitation for AD patients likely stems from intact procedural knowledge.

Purpose Amyloid (Aβ) brain deposition can occur in cognitively normal individuals and is associated with cortical volume abnormalities. Aβ-related volume changes are inconsistent across studies. Since volume is composed of surface area and thickness, the relative contribution of Aβ deposition on each of these metrics remains to be understood in cognitively normal individuals. Methods A group of 104 cognitively normal individuals underwent neuropsychological assessment, PiB-PET scan, and MRI acquisition. Surface-based cortical analyses were performed to investigate the effects of cortical and subcortical Aβ burden on cortical volume, thickness, and surface area. Mediation analyses were used to study the effect of thickness and surface area on Aβ-associated volume changes. We also investigated the relationships between structural metrics in clusters with abnormal morphology and regions underlying resting-state functional networks and cognitive performance. Results Cortical Aβ was not associated with cortical morphology. Subcortical Aβ burden was associated with changes in cortical volume, thickness, and surface area. Aβ-associated volume changes were driven by cortical surface area with or without thickness but never by thickness alone. Aβ-associated changes overlapped greatly with regions from the default mode network and were associated with lower performance in visuospatial abilities, episodic memory, and working memory. Conclusions In cognitively normal individuals, subcortical Aβ is associated with cortical volume, and this effect was driven by surface area with or without thickness. Aβ-associated cortical changes were found in the default mode network and affected cognitive performance. Our findings demonstrate the importance of studying subcortical Aβ and cortical surface area in normal ageing

Amyloid‐beta (Aβ) deposition is one of the main hallmarks of Alzheimer's disease. The study assessed the associations between cortical and subcortical (11)C‐Pittsburgh Compound B (PiB) retention, namely, in the hippocampus, amygdala, putamen, caudate, pallidum, and thalamus, and subcortical morphology in cognitively normal individuals. We recruited 104 cognitive normal individuals who underwent extensive neuropsychological assessment, PiB–positron emission tomography (PET) scan, and 3‐T magnetic resonance imaging (MRI) acquisition of T1‐weighted images. Global, cortical, and subcortical regional PiB retention values were derived from each scan and subcortical morphology analyses were performed to investigate vertex‐wise local surface and global volumes, including the hippocampal subfields volumes. We found that subcortical regional Aβ was associated with the surface of the hippocampus, thalamus, and pallidum, with changes being due to volume and shape. Hippocampal Aβ was marginally associated with volume of the whole hippocampus as well as with the CA1 subfield, subiculum, and molecular layer. Participants showing higher subcortical Aβ also showed worse cognitive performance and smaller hippocampal volumes. In contrast, global and cortical PiB uptake did not associate with any subcortical metrics. This study shows that subcortical Aβ is associated with subcortical surface morphology in cognitively normal individuals. This study highlights the importance of quantifying subcortical regional PiB retention values in these individuals.

We aimed to investigate cortical and subcortical brain alterations in people with Parkinson’s disease with polysomnography-confirmed rapid eye movement (REM) sleep behavior disorder (RBD). Thirty people with Parkinson’s disease, including 15 people with RBD, were recruited and compared with 41 healthy controls. Surface-based cortical and subcortical analyses were performed on T1-weighted images to investigate thickness and shape abnormalities between groups, and voxel-based and deformation-based morphometry were performed to investigate local volume. Correlations were performed in patients to investigate the structural correlates of motor activity during REM sleep. People with RBD showed cortical thinning in the right perisylvian and inferior temporal cortices and shape contraction in the putamen compared with people without RBD. Compared with controls, people with RBD had extensive cortical thinning and volume loss, brainstem volume was reduced, and shape contraction was found in the basal ganglia and hippocampus. In comparison to controls, people without RBD showed more restricted thinning in the sensorimotor, parietal, and occipital cortices, reduced volume in the brainstem, temporal and more posterior areas, and shape contraction in the pallidum and hippocampus. In Parkinson’s disease, higher tonic and phasic REM sleep motor activity was associated with contraction of the thalamic surface, extensive cortical thinning, and subtle volume reduction in the middle temporal gyrus. In Parkinson’s disease, the presence of RBD is associated with extensive cortical and subcortical abnormalities, suggesting more severe neurodegeneration in people with RBD. This provides potential neuroanatomical correlates for the more severe clinical phenotype reported in people with Parkinson’s disease with RBD.

Resume Les deficits de memoire prospective (MP) font partie des principales plaintes rapportees par des individus presentant un trouble cognitif leger (Mild cognitive impairment [MCI]). Bien que peu d’etudes s’y soient interessees, on reconnait generalement que les troubles de la MP pourraient constituer un marqueur precoce permettant d’identifier les individus a risque d’evoluer vers une demence. En depit de leur frequence elevee et de leurs consequences fonctionnelles appreciables, les deficits de MP font rarement l’objet d’une evaluation formelle en contexte clinique, car il existe peu de tests standardises ou d’outils cliniques sensibles et fiables. Dans cet article, nous ferons un survol de la litterature actuelle des etudes portant sur l’evaluation de la MP dans le MCI, avec une attention particuliere portee sur les diverses methodes d’evaluation actuellement disponibles. Nous rapporterons egalement des resultats preliminaires d’etudes qui ont ete faites dans notre laboratoire. Ces informations serviront de base pour, nous l’esperons, stimuler les cliniciens a evaluer l’integrite de la MP chez leurs patients âges chez qui on soupconne une deterioration du fonctionnement cognitif.

Objective Central artery stiffness is a confirmed predictor of cardiovascular health status that has been consistently associated with cognitive dysfunction and dementia. The European Society of Hypertension has established a threshold of arterial stiffness above which a cardiovascular event is likely to occur. However, the threshold at which arterial stiffness alters brain integrity has never been established. Methods The aim of this study is to determine the arterial stiffness cut-off value at which there is an impact on the white matter microstructure. This study has been conducted with 53 cognitively elderly without dementia. The integrity of the white matter was assessed using diffusion tensor metrics. Central artery stiffness was evaluated by measuring the carotid-femoral pulse wave velocity (cfPWV). The statistical analyses included 4 regions previously denoted vulnerable to increased central arterial stiffness (the corpus callosum, the internal capsule, the corona radiata and the superior longitudinal fasciculus). Results The results of this study call into question the threshold value of 10 m/s cfPWV established by the European Society of Hypertension to classify patients in neuro-cardiovascular risk groups. Our results suggest that the cfPWV threshold value would be approximately 8.5 m/s when the microstructure of the white matter is taken as a basis for comparison. Conclusions Adjustment of the cfPWV value may be necessary for a more accurate distinction between lower and higher risk group of patients for white matter microstructural injury related to arterial stiffness. Targeting the highest risk group for prevention methods may, in turn, help preserve brain health and cognitive functions., Highlights • DTI (FA, RD) analysis of white matter microstructure reveals that the cfPWV cut-off value (10 m/s) may be too high • This study rather suggests a value of cfPWV cut-off of 8.5 m/s to separate lower and higher neurovascular risk groups • Better executive function performance is correlated with higher FA and lower RD in participants with a cfPWV above 8.5 m/s.

The stiffness of large arteries and increased pulsatility can have an impact on the brain white matter (WM) microstructure, however those mechanisms are still poorly understood. The aim of this study was to investigate the association between central artery stiffness, axonal and myelin integrity in 54 cognitively unimpaired elderly subjects (65-75 years old).The neuronal fiber integrity of brain WM was assessed using diffusion tensor metrics and magnetization transfer imaging as measures of axonal organization (Fractional anisotropy, Radial diffusivity) and state of myelination (Myelin volume fraction). Central artery stiffness was measured by carotid-femoral pulse wave velocity (cfPWV). Statistical analyses included 4 regions (the corpus callosum, the internal capsule, the corona radiata and the superior longitudinal fasciculus) which have been previously denoted as vulnerable to increased central artery stiffness.cfPWV was significantly associated with fractional anisotropy and radial diffusivity (p 0.05, corrected for multiple comparisons) but not with myelin volume fraction. Findings from this study also show that improved executive function performance correlates with Fractional anisotropy positively (p 0.05 corrected) as well as with myelin volume fraction and radial diffusivity negatively (p 0.05 corrected).These findings suggest that arterial stiffness is associated with axon degeneration rather than demyelination. Controlling arterial stiffness may play a role in maintaining the health of WM axons in the aging brain.

Although empathy is an indispensable competence to social adaptation throughout the lifespan, it has been mostly studied with subjective, questionnaire-based measures in the context of healthy aging. Electroencephalography (EEG) provides an objective measure to investigate underlying neurophysiological processes related to empathy through mu rhythm. The current study used empathy-related mu rhythm during the observation of emotional facial expressions (EFE) in addition to the Empathy Quotient questionnaire in order to explore age-related changes of empathy across sexes. A total of 65 participants, including 33 young adults and 32 seniors, took part in this study. They were instructed to observe as well as to try experiencing emotional facial expressions (joy, fear, neutral) depicted on short video clips during which continuous EEG was recorded. They also completed the Empathy Quotient (EQ) questionnaire. Young adults reacted more strongly to emotional EFEs. Seniors perceived themselves as less empathic and exhibited an equivalent neurophysiological response to emotional and neutral stimuli. A significant sex effect in favour of females was found on mu rhythm modulation. Mu rhythm appears to be an age and sex sensitive neurophysiological marker linked to empathy and could therefore serve as an objective measure of empathy.

Semantic memory impairment has been documented in older individuals with amnestic Mild cognitive impairment (aMCI), who are at risk of developing Alzheimer’s disease (AD), yet little is known about the neural basis of this breakdown. The main objective of this study was to investigate the brain mechanisms associated with semantic performance in patients with aMCI. Method: A group of aMCI patients and a group of healthy older controls carried out a semantic categorization task while their brain activity was recorded using magnetoencephalography (MEG). During the task, participants were shown famous faces and had to determine whether each famous person matched a given occupation. The main hypotheses were that: (i) semantic processing should be compromised for aMCI patients, and (ii) these deficits should be associated with cortical dysfunctions within specific areas of the semantic network. Results: Behavioural results showed that aMCI participants were significantly slower and less accurate than control participants at the semantic task, corroborating previous reports. Additionally, relative to controls, a significant pattern of hyperactivation was found in the aMCI group within specific regions of the semantic network, including the right anterior temporal lobe and inferior prefrontal cortex. Conclusions: Abnormal functional activation within key areas of the semantic network suggests that it is compromised early in the disease process. Moreover, this pattern of increased activation in aMCI was positively associated with grey matter integrity in specific areas, but was not associated with any specific pattern of atrophy, suggesting that functional hyperactivation may precede atrophy of the semantic network in aMCI.

The Clock Drawing Test (CDT) is frequently used to screen for cognitive impairment, however, normative data for Rouleau et al.'s scoring system are scarce. The present study aims to provide norms for Rouleau et al.'s scoring system that are tailored to Quebec French-speaking mid- and older aged healthy adults.Six researchers from various research centers across the Province of Quebec (Canada) sent anonymous data for 593 (391 women) healthy community-dwelling volunteers (age range: 43-93 years; education range: 5-23 years) who completed the CDT 'drawing on command' version. This command version (setting the clock hands to 11:10, without a pre-drawn circle) was administrated as part of a more extensive neuropsychological assessment, or along with cognitive screening instruments. Each drawn clock was scored according to the quantitative criteria set by Rouleau et al.'s scoring system.CDT scores were significantly correlated with age (r(592) = -.132, p = .001) and years of education (r(592) = .116, p = .005), but not with sex (r(592) = .065, p = .112). Since data were skewed towards higher test scores, the percentiles method was used for analysis. Percentile ranks stratified by age and education are presented.These normative data for Rouleau et al.'s scoring system will contribute towards adequately screening for cognitive decline in Quebec French-speaking healthy adults, by also taking into account individual characteristics such as age and education.

Using standardized tests such as the Mini Mental State Examination (Folstein et al., 1975) to assess cognition of deaf persons using sign language lacks validity due to the fact that norms used come from normal hearing individuals (Baker & Baker, 2011). In addition, previous research reported the unreliability of using an interpreter for cognitive evaluation due to language and cultural differences between deaf signers and hearing oral speakers (Hill-Briggs et al., 2007; Dean et al., 2009). According to Atkinson et al. (2015), the assessment tools to evaluate cognitive deficits of older adult deaf signers should be designed in sign language. The aim of this research was to present an adapted version of the British Sign Language Cognitive Screening Test (BSL-CST) in Québec Sign Language (LSQ - used in Québec and part of Ontario). The BSL-CST is a cognitive assessment tool developed in British Sign Language, validated and normed with a British deaf population (Atkinson et al., 2015). The proposed test adapted in LSQ will be presented in a video format. We thus will present the cultural adaptation steps following the protocol of Vallerand (1989) with the considerations of Atkinson et al. (2015). The linguistic adaptation follows the steps of the World Health Organization’s (2016) protocol of adaptation and translation of instruments. Every phase of the adaptation has been validated with a team of deaf signers and French-LSQ expert interpreters. This tool adapted in LSQ, when normed, will represent a valid assessment tool for cognitive deficits of deaf signers using LSQ.

The aim of this study was to investigate the comprehension of concrete, abstract and abstract emotional words in semantic variant primary progressive aphasia (svPPA), Alzheimer's disease (AD), and healthy elderly adults (HE) Three groups of participants (9 svPPA, 12 AD, 11 HE) underwent a general neuropsychological assessment, a similarity judgment task, and structural brain MRI. The three types of words were processed similarly in the group of AD participants. In contrast, patients in the svPPA group were significantly more impaired at processing concrete words than abstract words, while comprehension of abstract emotional words was in between. VBM analyses showed that comprehension of concrete words relative to abstract words was significantly correlated with atrophy in the left anterior temporal lobe. These results support the view that concrete words are disproportionately impaired in svPPA, and that concrete and abstract words may rely upon partly dissociable brain regions.

The anterior temporal lobes (ATLs) have been consistently associated with semantic processing which, in turn, has a key role in reading aloud single words. This study aimed to investigate (1) the reading abilities in patients with the semantic variant of primary progressive aphasia (svPPA), and (2) the relationship between gray matter (GM) volume of the left ATL and word reading performance using voxel-based morphometry (VBM). Three groups of participants (svPPA, Alzheimer’s Disease, AD and healthy elderly adults) performed a reading task with exception words, regular words and pseudowords, along with a structural magnetic resonance imaging scan. For exception words, the svPPA group had a lower accuracy and a greater number of regularization errors as compared to the control groups of healthy participants and AD patients. Similarly, for regular words, svPPA patients had a lower accuracy in comparison with AD patients, and a greater number of errors related to complex orthography-to-phonology mappings (OPM) in comparison to both control groups. VBM analyses revealed that GM volume of the left ATL was associated with the number of regularization errors. Also, GM volume of the left lateral ATL was associated with the number of errors with complex OPM during regular word reading. Our results suggest that the left ATL might play a role in the reading of exception words, in accordance with its role in semantic processing. Results further support the involvement of the left lateral ATL in combinatorial processes, including the integration of semantic and phonological information, for both exception and regular words.

Objective Famous people knowledge has been shown to be impaired early in Alzheimer's disease (AD) and amnestic mild cognitive impairment (aMCI). However, the question of whether recently acquired knowledge is more impaired than remotely acquired knowledge remains a matter of debate. The aim of this study was to investigate the patterns of semantic memory impairment in aMCI and AD by investigating 2 factors that may influence the retrieval of such knowledge, namely remoteness and frequency of repetition of information over time. Method Three groups (19 controls, 20 aMCI, and 20 AD patients) were compared on a test assessing general and specific biographical knowledge about famous people, where the period of acquired fame (remote vs. recent) and the type of fame (enduring vs. transient) were controlled for. Results Global performance of aMCI and AD patients was significantly poorer than that of controls. However, different patterns of recall were observed as a function of time and type of fame. A temporal gradient was found in both patient groups for enduring names but not for transient ones, whereby knowledge about remote enduring famous persons was better recalled. Patients were more impaired at questions assessing specific biographical knowledge (unique to an individual) than more general knowledge. Conclusions Tests of famous people knowledge offer a unique opportunity to investigate semantic deficits in aMCI and AD, because they make it possible to estimate the time at which memories were acquired, as well as the type of fame. Results are discussed in light of memory consolidation models. (PsycINFO Database Record

Performance on verbal memory tests is generally associated with socio-demographic variables such as age, sex, and education level. Performance also varies between different cultural groups. The present study aimed to establish normative data for the Rappel libre/Rappel indice a 16 items (16-item Free and Cued Recall; RL/RI-16), a French adaptation of the Free and Cued Selective Reminding Test (Buschke, 1984; Grober, Buschke, Crystal, Bang, & Dresner, 1988). The sample consisted of 566 healthy French-speaking older adults (50-88 years old) from the province of Quebec, Canada. Normative data for the RL/RI-16 were derived from 80% of the total sample (normative sample) and cross-validated using the remaining participants (20%; validation sample). The effects of participants' age, sex, and education level were assessed on different indices of memory performance. Results indicated that these variables were independently associated with performance. Normative data are presented as regression equations with standard deviations (symmetric distributions) and percentiles (asymmetric distributions).

Arterial stiffness and blood pressure (BP) are contributors to cognitive decline and dementia. Lower global cerebral blood flow (CBF) is one of the earliest manifestations of biological alterations linked to cognitive decline, nevertheless the best cardiovascular predictor of CBF in gray-matter (CBF-GM) remains to be identified. Our objective is to determine the best predictor of CBF-GM levels amongst cardiovascular parameters. Eigthy-four healthy participants between 60-80 years-old were evaluated. The measured parameters for arterial stiffness were the carotid-femoral pulse wave velocity (cf-PWV) and the augmentation index (Aix), measured by applanation tonometry (SphygmoCor). Mean systolic BP (SBP) was monitored over 24-hours and analyzed following Hypertension-Canada’s guidelines(2018). The coefficient of variation for 24-hours SBP was calculated by dividing the standard deviation by the mean. Resting CBF-GM was quantified from pseudocontinuous arterial-spin-labeling using Neurolens 2.0(pcASL), and acquired on a 3T scanner (MAGNETOM Prisma-Fit). We created multiple linear regression models for each independent variable (cf-PWV, Aix, mean-SBP in 24 hours and the coefficient of variation of 24-hours SBP) using age, sex, schooling and body mass index as covariates. Multiple linear regression models demonstrated that two independent variables could predict CBF-GM levels: a)PWV (p=0.010) and b)Aix (p=0.006). In this cohort, we demonstrated that while PWV and Aix are both predictors of CBF-GM levels, it is Aix which has the highest predictive value and could be a useful tool to understand the interplay between lower CBF-GM and arterial stiffness. These results also indicate that Aix may be a good therapeutic target to preserve brain health and cognition.

Les progrès faits dans le domaine des technologies du numérique ces dernières décennies sont spectaculaires, en particulier dans le champ de la santé, mettant à la disposition des chercheurs et des cliniciens de très nombreux outils pour prévenir, diagnostiquer, accompagner et/ou guérir. La neuropsychologie du xxie siècle, à en croire des auteurs tel Parsons [1] ou encore Kane et Parsons [2], accuse un retard important dans l’adoption et l’utilisation du numérique et des nouvelles technologies dans ses pratiques cliniques, tant pour l’évaluation que pour la revalidation des patients. Elle reste en effet encore très attachée aux tests, questionnaires, exercices et aides cognitives de format « papier-crayon », faisant dire à Parsons [1] que si « la neuropsychologie clinique insiste sur son rôle en tant que science, sa technologie ne progresse pas au même rythme que dans les autres domaines des neurosciences cliniques ». Dans un sondage réalisé auprès de neuropsychologues canadiens et américains, parmi une recension de 693 instruments distincts utilisés, seulement 6 % étaient informatisés et typiquement les tests informatisés étaient jamais ou rarement utilisés [3]. Dans la même logique, dès 1997, Sternberg [4] pointait le peu de progrès effectués dans le champ de l’évaluation neuropsychologique, estimant que les cliniciens utilisaient encore beaucoup de tests datant de l’invention du poste de télévision noir et blanc, tests n’ayant fait l’objet que de modifications d’ajouts ou de suppressions de sous-tests ou de mises à jour de normes au fil des dernières décennies…

Semantic deficits in Alzheimer's disease (AD) are often more severe for items that are characterized by a unique semantic and lexical association, such as famous people. Whether these deficits are due to the degradation of semantic information or a deficit in the ability to intentionally access semantic knowledge remains controversial. To assess the integrity of the semantic system without explicitly accessing it, a priming paradigm was used. Semantic and repetition priming effects in individuals with AD (n = 7) and age-matched controls (n = 13) were measured in a familiarity judgment task using visually-presented names of famous people. A defective priming effect in AD subjects was observed in the semantic priming but not in the repetition priming condition. Therefore, the semantic impairments observed in AD may indicate a degraded representation of the semantic information concerning famous people.