Effects of Diversity and Neuropsychological Performance in an NFL Cohort

Objective: The aim of this study was to examine the effect of ethnicity on neuropsychological test performance by comparing scores of white and black former NFL athletes on each subtest of the WMS. Participants and Methods: Data was derived from a de-identified database in South Florida consisting of 63 former NFL white (n=28, 44.4%) and black (n=35, 55.6%) athletes (Mage= 50.38; SD= 11.57). Participants completed the following subtests of the WMS: Logical Memory I and II, Verbal Paired Associates I and II, and Visual Reproduction I and II. Results: A One-Way ANOVA yielded significant effect between ethnicity and performance on several subtests from the WMS-IV. Black athletes had significantly lower scores compared to white athletes on Logical Memory II: F(1,61) = 4.667, p= .035, Verbal Paired Associates I: F(1,61) = 4.536, p = .037, Verbal Paired Associates: II F(1,61) = 4.677, p = .034, and Visual Reproduction I: F(1,61) = 6.562, p = .013. Conclusions: Results suggest significant differences exist between white and black athletes on neuropsychological test performance, necessitating the need for proper normative samples for each ethnic group. It is possible the differences found can be explained by the psychometric properties of the assessment and possibility of a non-representative sample for minorities, or simply individual differences. Previous literature has found white individuals to outperform African-Americans on verbal and non-verbal cognitive tasks after controlling for socioeconomic and other demographic variables (Manly & Jacobs, 2002). This highlights the need for future investigators to identify cultural factors and evaluate how ethnicity specifically plays a role on neuropsychological test performance. Notably, differences between ethnic groups can have significant implications when evaluating a sample of former athletes for cognitive impairment, as these results suggest retired NFL minorities may be more impaired compared to retired NFL white athletes

Distinguishing Performance on Tests of Executive Functions Between Those with Depression and Anxiety

Objective: To see if there are differences in executive functions between those diagnosed with Major Depressive Disorder (MDD) and those with Generalized Anxiety Disorder (GAD).Participants and Methods: The data were chosen from a de-identified database at a neuropsychological clinic in South Florida. The sample used was adults diagnosed with MDD (n=75) and GAD (n=71) and who had taken the Halstead Category Test, Trail Making Test, Stroop Test, and the Wisconsin Card Sorting Test. Age (M=32.97, SD=11.75), gender (56.7% female), and race (52.7% White) did not differ between groups. IQ did not differ but education did (MDD=13.41 years, SD=2.45; GAD=15.11 years, SD=2.40), so it was ran as a covariate in the analyses. Six ANCOVAs were run separately with diagnosis being held as the fixed factor and executive function test scores held as dependent variables. Results: The MDD group only performed worse on the Category Test than the GAD group ([1,132]=4.022, p\u3c .05). Even though both WCST scores used were significantly different between the two groups, both analyses failed Levene’s test of Equality of Error Variances, so the data were not interpreted. Conclusions: Due to previous findings that those diagnosed with MDD perform worse on tests of executive function than normal controls (Veiel, 1997), this study wanted to compare executive function performance between those diagnosed with MDD and those with another common psychological disorder. The fact that these two groups only differed on the Category Test shows that there may not be much of a difference in executive function deficits between those with MDD and GAD. That being said, not being able to interpret the scores on the WCST test due to a lack of homogeneity of variance indicates that a larger sample size is needed to compare these two types of patients, as significant differences may be found. The results of this specific study, however, could mean that the Category Test could be used in assisting the diagnosis of a MDD patient

The Effect of Ethnicity on Neuropsychological Test Performance of Former NFL Athletes

Objective: To investigate the effect of ethnicity on neuropsychological test performance by specifically exploring differences between white and black former NFL athletes on subtests of the WAIS-IV. Participants and Methods: Data was derived from a de-identified database in Florida consisting of 63 former NFL athletes (Mage=50.38; SD=11.57); 28 white and 35 black. Participants completed the following subtests of the WAIS-IV: Block Design, Similarities, Digit Span, Matrix Reasoning, Arithmetic, Symbol Search, Visual Puzzles, Coding, and Cancellation. Results: One-Way ANOVA yielded a significant effect between ethnicity and performance on several subtests. Black athletes had significantly lower scaled scores than white athletes on Block Design F(1,61)=14.266, p\u3c.001, Similarities F(1,61)=5.904, p=.018, Digit Span F(1,61)=8.985, p=.004, Arithmetic F(1,61)=16.07, p\u3c.001 and Visual Puzzles F(1,61)=16.682, p\u3c .001. No effect of ethnicity was seen on performance of Matrix Reasoning F(1,61)=2.937, p=.092, Symbol Search F(1,61)=3.619, p=.062, Coding F(1,61)=3.032, p=.087 or Cancellation F(1,61)=2.289, p=.136. Conclusions: Results reveal significant differences between white and black athletes on all subtests of the WAIS-IV but those from the Processing Speed Scale and Matrix Reasoning. These findings align with previous literature that found white individuals to outperform African-Americans on verbal and non-verbal tasks after controlling for socioeconomic and demographic variables (Manly & Jacobs, 2002). These differences may also be a reflection of the WAIS-IV’s psychometric properties and it is significant to consider the normative sample used may not be appropriate for African-Americans. This study highlights the need for future research to identify how ethnicity specifically influences performance, sheds light on the importance of considering cultural factors when interpreting test results, and serves as a call to action to further understand how and why minorities may not be accurately represented in neuropsychological testing

Regional Cerebral Blood Flow Patterns in Children vs. Adults with ADHD Combined and Inattentive Types: A SPECT Study

Objective: The current study sought to determine whether ADHD Combined Type (ADHD-C) and ADHD Primarily Inattentive Type (ADHD-PI) showed differential regional cerebral blood flow (rCBF) patterns in children vs. adults. Participants and Methods: The overall sample (N=1484) was effectively split into four groups: adults with ADHD-PI (n=519), adults with ADHD-C (n=405), children with ADHD-PI (n=192), children with ADHD-C (n=368). All participants were void of bipolar, schizophrenia, autism, neurocognitive disorders, and TBI. The data were collected from a de-identified archival database of individuals who underwent SPECT scans at rest. Results: Using αConclusions: Overall, the current study suggested that children may show rCBF differences between different ADHD subtypes, but adults may not. The current study did not find significance in any of the 17 brain regions examined when comparing adults with ADHD-C to adults with ADHD-PI. All significant findings were attributed to the children with ADHD-C group showing aberrant blood flow rate than at least one other group. Previous research has supported that the differentiation of these subtypes as distinctive disorders is difficult to make in adults (Sobanski et al., 2006). Other research has indicated the potential of imaging techniques to differentiate the two in children (Al-Amin, Zinchenko, & Geyer, 2018). The current findings support nuanced ways in which rCBF patterns of ADHD-C and ADHD-PI differ between children and adults

A computational atlas of the hippocampal formation using ex vivo, ultra-high resolution MRI: Application to adaptive segmentation of in vivo MRI.

AbstractAutomated analysis of MRI data of the subregions of the hippocampus requires computational atlases built at a higher resolution than those that are typically used in current neuroimaging studies. Here we describe the construction of a statistical atlas of the hippocampal formation at the subregion level using ultra-high resolution, ex vivo MRI. Fifteen autopsy samples were scanned at 0.13mm isotropic resolution (on average) using customized hardware. The images were manually segmented into 13 different hippocampal substructures using a protocol specifically designed for this study; precise delineations were made possible by the extraordinary resolution of the scans. In addition to the subregions, manual annotations for neighboring structures (e.g., amygdala, cortex) were obtained from a separate dataset of in vivo, T1-weighted MRI scans of the whole brain (1mm resolution). The manual labels from the in vivo and ex vivo data were combined into a single computational atlas of the hippocampal formation with a novel atlas building algorithm based on Bayesian inference. The resulting atlas can be used to automatically segment the hippocampal subregions in structural MRI images, using an algorithm that can analyze multimodal data and adapt to variations in MRI contrast due to differences in acquisition hardware or pulse sequences. The applicability of the atlas, which we are releasing as part of FreeSurfer (version 6.0), is demonstrated with experiments on three different publicly available datasets with different types of MRI contrast. The results show that the atlas and companion segmentation method: 1) can segment T1 and T2 images, as well as their combination, 2) replicate findings on mild cognitive impairment based on high-resolution T2 data, and 3) can discriminate between Alzheimer's disease subjects and elderly controls with 88% accuracy in standard resolution (1mm) T1 data, significantly outperforming the atlas in FreeSurfer version 5.3 (86% accuracy) and classification based on whole hippocampal volume (82% accuracy)

Neurosurgery in Obsessive Compulsive Disorder:From targets to treatment to tracts and back again

People with obsessive compulsive disorder (OCD) suffer from obsessive thoughts and/or behavior, with a constant presence that can hardly be ignored. A range of interventions is effective in the management of OCD including behavioral therapy, cognitive therapy and cognitive behavioral therapy (CBT). In addition, a large body of evidence advocate on the use of selective serotonin reuptake inhibitors (SSRIs) and clomipramine, a tricyclic antidepressant, in the treatment of OCD, often used in combination with CBT. However, 40-60% of patients remain treatment-refractory, defined as a less than 25% reduction in Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) score. This scale is used to determine the severity of the disorder. The resistance of such a big amount of patients to therapy may urge the need for alternative treatment strategies, such as deep brain stimulation (DBS) of subcortical structures or gamma knife ventral capsulotomy (GVC), a noninvasive procedure using gamma rays to destroy certain brain tissues. The first part of this thesis aimed at identifying fiber bundles associated with clinical response to DBS or GVC. OCD patients consistently underperform across multiple cognitive domains. The second part of this thesis was focused on the neuropsychological outcome of OCD DBS in order to identify a cognitive pattern associated with a good outcome or that would (in part) help explain the functional mechanism of OCD-DBS. The third part focused on several postoperative aspects of (OCD)-DBS patients including surgical and hardware related adverse events of DBS and reviewing the effectiveness, timing and procedural aspects of CBT after DBS with the aim to provide clinical recommendations

Effectiveness of intensive physiotherapy for gait improvement in stroke: systematic review

Introduction: Stroke is one of the leading causes of functional disability worldwide. Approximately 80% of post-stroke subjects have motor changes. Improvement of gait pattern is one of the main objectives of physiotherapists intervention in these cases. The real challenge in the recovery of gait after stroke is to understand how the remaining neural networks can be modified, to be able to provide response strategies that compensate for the function of the affected structures. There is evidence that intensive training, including physiotherapy, positively influences neuroplasticity, improving mobility, pattern and gait velocity in post-stroke recovery. Objectives: Review and analyze in a systematic way the experimental studies (RCT) that evaluate the effects of Intensive Physiotherapy on gait improvement in poststroke subjects. Methodology: Were only included all RCT performed in humans, without any specific age, that had a clinical diagnosis of stroke at any stage of evolution, with sensorimotor deficits and functional gait changes. The databases used were: Pubmed, PEDro (Physiotherapy Evidence Database) and CENTRAL (Cochrane Center Register of Controlled Trials). Results: After the application of the criteria, there were 4 final studies that were included in the systematic review. 3 of the studies obtained a score of 8 on the PEDro scale and 1 obtained a score of 4. The fact that there is clinical and methodological heterogeneity in the studies evaluated, supports the realization of the current systematic narrative review, without meta-analysis. Discussion: Although the results obtained in the 4 studies are promising, it is important to note that the significant improvements that have been found, should be carefully considered since pilot studies with small samples, such as these, are not designed to test differences between groups, in terms of the effectiveness of the intervention applied. Conclusion: Intensive Physiotherapy seems to be safe and applicable in post-stroke subjects and there are indications that it is effective in improving gait, namely speed, travelled distance and spatiotemporal parameters. However, there is a need to develop more RCTs with larger samples and that evaluate the longterm resultsN/

Do informal caregivers of people with dementia mirror the cognitive deficits of their demented patients?:A pilot study

Recent research suggests that informal caregivers of people with dementia (ICs) experience more cognitive deficits than noncaregivers. The reason for this is not yet clear. Objective: to test the hypothesis that ICs ‘mirror' the cognitive deficits of the demented people they care for. Participants and methods: 105 adult ICs were asked to complete three neuropsychological tests: letter fluency, category fluency, and the logical memory test from the WMS-III. The ICs were grouped according to the diagnosis of their demented patients. One-sample ttests were conducted to investigate if the standardized mean scores (t-scores) of the ICs were different from normative data. A Bonferroni correction was used to correct for multiple comparisons. Results: 82 ICs cared for people with Alzheimer's dementia and 23 ICs cared for people with vascular dementia. Mean letter fluency score of the ICs of people with Alzheimer's dementia was significantly lower than the normative mean letter fluency score, p = .002. The other tests yielded no significant results. Conclusion: our data shows that ICs of Alzheimer patients have cognitive deficits on the letter fluency test. This test primarily measures executive functioning and it has been found to be sensitive to mild cognitive impairment in recent research. Our data tentatively suggests that ICs who care for Alzheimer patients also show signs of cognitive impairment but that it is too early to tell if this is cause for concern or not

Corrélats neurofonctionnels des habiletés lexico-sémantiques selon le décours et les expériences de vie

Le vieillissement des sociétés dans le monde s’accompagne d’immenses possibilités en même temps que de nombreux défis en matière de santé et de bien-être. Comme en témoignent les aînés, la qualité de vie lors du vieillissement dépend fortement de l’état de santé cognitive. Une meilleure compréhension des constituants de la santé cognitive constitue donc un élément central dans le défi qui attend les neuroscientifiques. Pour accomplir efficacement les activités cognitives quotidiennes, les régions du cerveau synchronisent leur activité l’une avec l’autre, tel que mesuré par la connectivité fonctionnelle basée sur les données de l’imagerie cérébrale. Les méthodes utilisant la connectivité fonctionnelle ont permis de mettre en avant une architecture relativement stable en soutien aux processus cognitifs. Cette organisation fonctionnelle serait en grande partie déterminée par l’architecture présente au « repos » (l’activité spontanée non contrôlée), mais serait également modulée par le type et le niveau d’activité dans les réseaux spécifiques à la tâche. À ce jour, il n’est pas clair si l’activité cognitive module l’association entre les mesures de connectivité fonctionnelle et l’âge, ou encore les expériences de vie, suspectées de soutenir le maintien des performances cognitives à travers un phénomène de réserve neurocognitive. Cette question est particulièrement d’intérêt dans le cadre des habiletés lexico-sémantiques, qui apparaissent -de manière générale- exceptionnellement bien préservées avec l’âge. Cette thèse, articulée en trois études, vise donc à décrire et comparer l’effet de l’âge sur les patrons de connectivité fonctionnelle lors de tâches lexico-sémantiques et au repos, ainsi qu’à caractériser l’influence de la complexité de la tâche et des expériences de vie sur les relations unissant âge et performance cognitive. Une première étude -grâce à l’imagerie cérébrale- décrit les interactions fonctionnelles entre régions lors de diverses tâches de vocabulaire. L’objectif de cette première étude est de décrire les changements de connectivité fonctionnelle liés à l’âge en utilisant trois tâches langagières et de comparer ces changements avec ceux observés dans un état de repos, et ce, dans une cohorte de 300 adultes âgés entre 18 et 85 ans. Il faut en effet rappeler que la compréhension de la réorganisation du cerveau dans le vieillissement repose principalement sur des études au repos; ou sur un plus petit nombre d’études ayant exploré les capacités cognitives qui, typiquement, déclinent avec l’âge. Cette littérature a mené à l’élaboration de concepts et de modèles du vieillissement cognitif qui semblent transversaux aux domaines cognitifs. Toutefois, certaines habiletés, comme les capacités langagières lexico-sémantiques, sont caractérisées par la préservation générale de la performance dans le vieillissement, offrant ainsi une potentielle fenêtre privilégiée pour observer des mécanismes cognitifs efficaces. L’exploration des caractéristiques spécifiques à une activité pourrait donc offrir un nouveau regard sur les mécanismes qui sous-tendent un vieillissement cognitif optimal. Les résultats indiquent que les différences de connectivité fonctionnelles liées à l’âge varient d’un paradigme à l’autre et que l’état de repos présente des caractéristiques très distinctes des tâches. En particulier, les régions du réseau du langage montrent des augmentations de la connectivité au cours du vieillissement, tandis que seules des diminutions de connectivité caractérisent l’état de repos. Ces résultats ont été reproduits en manipulant différentes variables du modèle, suggérant une certaine robustesse. Une seconde étude s’attarde à décrire les différences d’architecture fonctionnelle entre jeunes et aînés dans le contexte de la réalisation de tâches de dénomination. La connectivité fonctionnelle induite par une tâche offre le potentiel de révéler des processus neurofonctionnels particulièrement adaptés à l’état cognitif. La manipulation méthodologique de la tâche devait donc permettre d’étudier avec précision les mécanismes neurofonctionnels qui soutiennent la préservation de la performance pour une activité cognitive donnée. Par exemple, l’utilisation d’un paradigme de tâche permet l’utilisation d’un atlas propre à la tâche et à l’échantillon au lieu des atlas génériques issus d’un état de repos, ou la manipulation du niveau de complexité. Le but de la deuxième étude est de décrire les changements de connectivité fonctionnelle liés à l’âge pendant l’accomplissement d’une tâche cognitive qui est typiquement préservée dans le vieillissement sain, ainsi que de comparer les différences liées à une complexité plus élevée, tel que défini par la fréquence lexicale. Les résultats suggèrent des mécanismes propres à l’âge et à la tâche. Les adultes plus âgés présentent une gamme complexe de différences dans l’architecture fonctionnelle, en particulier dans les régions motrices de la parole, mais aussi sous la forme d’une ségrégation accrue des régions classiquement attribuée au traitement sémantique. Seules quelques régions présentent un effet d’interaction significatif entre la demande intrinsèque de la tâche et les différences liées à l’âge, ce qui suggère des mécanismes spécifiques à la tâche plutôt que transversaux aux domaines cognitifs. Dans l’ensemble, les résultats de ces deux études confirment donc l’intérêt complémentaire des analyses en connectivité fonctionnelle induite par une tâche pour comprendre l’organisation cérébrale qui sous-tend le maintien de la performance cognitive au cours du vieillissement sain. Une troisième étude se focalise en conséquence sur les liens entre les expériences de vie cognitivement stimulantes et la performance comportementale durant l’accomplissement d’une tâche cognitive en décrivant l’architecture neurofonctionnelle d’adultes jeunes et âgés. Dans l’étude des facteurs sous-tendant la préservation cognitive dans le vieillissement, l’impact des expériences de vie cognitivement stimulantes (p.ex.: niveau d’éducation, activité professionnelle, activités quotidiennes) a attiré l’intérêt de nombreux chercheurs au cours des 20 dernières années. Il est par exemple suggéré que les expériences de vie cumulées contribuent à la préservation cognitive dans le vieillissement sain ainsi qu’aux premiers stades d’une maladie neurodégénérative. Une relation indirecte est soupçonnée entre les expériences de vie et l’activité cognitive, à travers l’activité neuronale. Toutefois, l’impact des expériences de vie sur les capacités de dénomination – une activité cognitive parmi les mieux conservées avec l’âge -- est encore inconnu. L’objectif de la troisième étude est de décrire les relations directes et indirectes entre la connectivité fonctionnelle, la performance aux tâches et les activités cognitivement stimulantes (éducation, profession, activités quotidiennes) chez les personnes âgées. Les résultats montrent que le niveau de performance est associé à des patrons distincts de connectivité fonctionnelle chez les personnes jeunes et âgées pendant la dénomination de mots. Dans le contexte d’une tâche généralement réussie, il n’existe toutefois pas de relation entre le niveau de participation à des activités stimulantes (p.ex. : éducation, profession, activités de loisirs) et la performance à la tâche chez les ainés, contrairement à ce qui est observé chez les adultes jeunes. En somme, les travaux de cette thèse supportent l’hypothèse selon laquelle les mesures de connectivité fonctionnelle s’avèrent sensibles à l’état cognitif, offrant ainsi un appui à l’utilisation de paradigmes soigneusement conçus pour répondre à des questions spécifiques sur le vieillissement cognitif. Lors de l’exécution réussie d’une tâche de dénomination de mots, les adultes plus âgés font preuve d’une synchronisation spécifique à la tâche entre régions cérébrales, en association avec le niveau de performance. Bien que les expériences de vie cognitivement stimulantes interagissent avec la connectivité fonctionnelle chez les personnes âgées, celles-ci semblent peu corrélées à la performance dans le contexte d’une habileté préservée. Ces résultats offrent une perspective alternative aux rapports sur les mécanismes neuronaux de domaine général dans le vieillissement et suggèrent que l’utilisation d’une méthodologie propre à l’échantillon et à la tâche peut s’avérer utile pour parvenir à un portrait complet des processus cognitifs sains en matière de vieillissement.The aging of societies worldwide comes with both immense opportunities as well as numerous challenges regarding health and wellness. As reported by older adults, quality of life in aging is heavily dependent upon cognitive health. A better understanding of the constituents of cognitive health is thus a central piece of the scientific challenge that awaits neuroscientists. For a cost-effective functioning in everyday cognitive activities, brain regions synchronize their activity one with another, as is measured by functional connectivity using neuroimaging. Functional connectivity has allowed for the recognition of a relatively stable architecture in charge of cognitive processes. This functional organization would be in large part determined by the architecture present at “rest” (the unconstrained spontaneous activity), but would also be modulated by the cognitive activity and by the cognitive demand in task-specific networks. The current understanding of the brain reorganization in aging relies mostly on either resting-state studies, or on a smaller number of studies that explored cognitive abilities typically declining with age. This literature led to the development of domain-general models and concepts regarding cognitive aging. Yet, little is known about task-specific patterns in functional connectivity with age. For example, lexical-semantic abilities are characterized by general preservation of performance in aging, therefore offering a potentially privileged window to observe efficient cognitive mechanisms. The exploration of task-specific characteristics could thus offer a new insight on neurofunctional mechanisms that define healthy aging, including potential reserve phenomenon. The general aim of this thesis, articulated in three studies, is to describe and compare the effect of age on functional connectivity patterns during lexico-semantic tasks and at rest, as well as to characterize the influence of task complexity and life experiences on the relationship between age and cognitive performance. The goal of the first study was to describe the age-related changes in functional connectivity using three language tasks in a large cohort of aging adults [18-85 years old] and to compare these changes with those observed in a resting state. Results show that age-related differences vary from one paradigm to another and that resting-state present very distinct pattern when compared with tasks. Notably, regions of the language network show age-related increases in connectivity while only age-related decreases characterize resting-state. These results remained stable even after manipulation of the model’s confounding variables, suggesting a certain robustness. Task-induced functional connectivity thus holds a potential to reveal neurofunctional processes that are distinctly adapted to the cognitive state. In consequence, a precise neurofunctional characterization for a given cognitive activity may benefit from a methodological fine-tuning. Such manipulation of the task may reveal neurofunctional mechanisms that support preserved cognitive abilities. For example, task paradigm allows the use of a sample and task-specific template instead of generic -resting-state- atlases, or the manipulation of the cognitive demand level. The goal of the second study was to describe the age-related changes of the functional connectivity patterns during the accomplishment of a cognitive task that is typically preserved in healthy aging, as well as to compare age-related differences under higher task demand, defined by lexical frequency. Results suggest both age and task-specific mechanisms. Older adults show a complex array of differences in functional connectivity architecture, especially so in speech motor regions, but also in the form of increased segregation of regions classically attributed to semantic processing. Only a few regions show a significant interaction effect between intrinsic task demand and age-related differences in functional connectivity. Altogether, the findings from the first two studies confirm the complementary interest of task-induced functional connectivity analysis to uncover the brain organization that subserves lexico-semantic abilities during healthy aging. Yet, little is known about what processes underly inter-individual differences in performance. In the investigation of preserved performance in aging, the impact of cognitively stimulating life experiences has drawn many interests in the past 20 years. Life experiences were indeed demonstrated to contribute to the preservation of cognitive performance in healthy aging and in the early stages of neurodegenerative diseases. This mechanism is suspected of operating through an indirect relationship between life experiences and cognitive activity via neural activity. It may also be mediated by the individual capacity to cope with the demand of the task. The impact of such lifetime experience on naming abilities --- amongst the best-preserved with age --- is still unknown. The goal of the third study was thus to describe the direct and indirect relationships between lifelong activities (i.e., education, occupation, everyday activities), functional connectivity, and task performance in older individuals. Results show that life experiences interact with functional connectivity during successful word naming among older individuals. An interaction with task demand was also noted in some brain regions, suggesting demand-dependent neural mechanisms. In conclusion, functional connectivity proves to be sensitive to the actual cognitive state, supporting the use of carefully designed paradigms to answer specific questions about cognitive aging. During the successful performance of a word naming task, older adults show a task-specific use of the brain connectome. While cognitively stimulating life experiences interact with functional connectivity in older adults, it appears poorly related to task performance in the context of preserved naming abilities. These findings offer an alternative perspective to previous reports of domain-general neural mechanisms in aging. Task and sample-specific designs may reveal useful to reach a complete characterization of successful cognitive processes in healthy aging