References of "Salmon, Eric"
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See detailSelf in Dementia
Antoine, Nicolas ULg; Genon, Sarah ULg; Bastin, Christine ULg et al

in Mishara; Corlett, P.; Fletcher, P. (Eds.) et al Phenomenological Neuropsychiatry, How Patient Experience Bridges Clinic with Clinical Neuroscience (in press)

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See detailFluctuations of Attentional Networks and Default Mode Network during the Resting State Reflect Variations in Cognitive States: Evidence from a Novel Resting-state
Van Calster, Laurens ULg; D'Argembeau, Arnaud ULg; SALMON, Eric ULg et al

in Journal of Cognitive Neuroscience (in press)

Neuroimaging studies have revealed the recruitment of a range of neural networks during the resting state, which might reflect a variety of cognitive experiences and processes occurring in an individual's ... [more ▼]

Neuroimaging studies have revealed the recruitment of a range of neural networks during the resting state, which might reflect a variety of cognitive experiences and processes occurring in an individual's mind. In this study, we focused on the default mode network (DMN) and attentional networks and investigated their association with distinct mental states when participants are not performing an explicit task. To investigate the range of possible cognitive experiences more directly, this study proposes a novel method of resting-state fMRI experience sampling, informed by a phenomenological investigation of the fluctuation of mental states during the resting state. We hypothesized that DMN activity would increase as a function of internal mentation and that the activity of dorsal and ventral networks would indicate states of top–down versus bottom–up attention at rest. Results showed that dorsal attention network activity fluctuated as a function of subjective reports of attentional control, providing evidence that activity of this network reflects the perceived recruitment of controlled attentional processes during spontaneous cognition. Activity of the DMN increased when participants reported to be in a subjective state of internal mentation, but not when they reported to be in a state of perception. This study provides direct evidence for a link between fluctuations of resting-state neural activity and fluctuations in specific cognitive processes. [less ▲]

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See detailThe neural bases of proactive and reactive control processes in normal aging
Manard, Marine ULg; François, Sarah ULg; Phillips, Christophe ULg et al

in Behavioural Brain Research (in press)

Introduction. Research on cognitive control suggests an age-related decline in proactive control abilities (anticipatory control), whereas reactive control (following conflict detection) seems to remain ... [more ▼]

Introduction. Research on cognitive control suggests an age-related decline in proactive control abilities (anticipatory control), whereas reactive control (following conflict detection) seems to remain intact. As proactive and reactive control abilities are associated with specific brain networks, this study investigated age-related effects on the neural substrates associated with each kind of control. Methods. In an event-related fMRI study, a modified version of the Stroop task was administered to groups of 20 young and 20 older healthy adults. Based on the theory of dual mechanisms of control, the Stroop task has been built to induce proactive or reactive control depending on task context. Results. Behavioral results (p < .05) indicated faster processing of interfering items in the mostly incongruent (MI) than the mostly congruent (MC) context in both young and older participants. fMRI results showed that reactive control is associated with increased activity in left frontal areas for older participants. For proactive control, decreased activity in the bilateral anterior cingulate cortex was associated with more activity in the right middle frontal gyrus in the older than the younger group. Conclusion. These observations support the hypothesis that aging affects the neural networks associated with reactive and proactive cognitive control differentially. These age-related changes are very similar to those observed in young adults with low dopamine availability, suggesting that a general mechanism (prefrontal dopamine availability) may modulate brain networks associated with various kinds of cognitive control. [less ▲]

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See detailIncreasing the salience of fluency cues does not reduce the recognition memory impairment in Alzheimer’s disease!
Simon, Jessica ULg; Bastin, Christine ULg; SALMON, Eric ULg et al

in Journal of Neuropsychology (in press)

In Alzheimer’s disease (AD), it is now well established that recollection is impaired from the beginning of the disease, whereas findings are less clear concerning familiarity. One of the most important ... [more ▼]

In Alzheimer’s disease (AD), it is now well established that recollection is impaired from the beginning of the disease, whereas findings are less clear concerning familiarity. One of the most important mechanisms underlying familiarity is the sense of familiarity driven by processing fluency. In this study, we attempted to attenuate recognition memory deficits in AD by maximizing the salience of fluency cues in two conditions of a recognition memory task. In one condition, targets and foils have been created from the same pool of letters (Overlap condition). In a second condition, targets and foils have been derived from two separate pools of letters (No-Overlap condition), promoting the use of letter-driven visual and phonetic fluency. Targets and foils were low-frequency words. The memory tasks were performed by 15 patients with AD and 16 healthy controls. Both groups improved their memory performance in the No-Overlap condition compared to the Overlap condition. Patients with AD were able to use fluency cues during recognition memory as older adults did, but this did not allow to compensate for dysfunction of recognition memory processes. [less ▲]

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See detailRelating pessimistic memory predictions to Alzheimer’s disease brain structure
Genon, Sarah ULg; Simon, Jessica ULg; Bahri, Mohamed Ali ULg et al

in Cortex : A Journal Devoted to the Study of the Nervous System & Behavior (in press)

Patients with Alzheimer’s disease (AD) show impairment of episodic memory and related metacognitive processes. The present study examined subjective metacognitive judgments preceding objective memory ... [more ▼]

Patients with Alzheimer’s disease (AD) show impairment of episodic memory and related metacognitive processes. The present study examined subjective metacognitive judgments preceding objective memory retrieval and investigated the neural correlates of pessimistic predictions for successfully retrieved memories in AD patients. AD patients and healthy older participants provided predictive judgements on their recognition performance before retrieval of famous (semantic) and recently learned (episodic) names. Correlations between grey matter volume (GMV) in T1 images and behavioural scores were examined with multivariate (PLS) and univariate (GLM) analyses in AD patients. AD patients showed a significant proportion of successful name recognition preceded by pessimistic prediction (Prediction_low_hits) in episodic memory. PLS revealed that behavioural pattern in AD patients was related with a mainly right lateralized pattern of GMV decrease including medial temporal lobe and posterior cingulate cortex, but also right ventrolateral prefrontal cortex (VLPFC). GLM further confirmed that pessimistic prediction negatively correlated with GMV in VLPFC. Thus, impaired monitoring processes (possibly influenced by inaccurate beliefs) allowing inferences about one’s own memory performance are primarily related to decrease GMV in VLPFC in AD patients. [less ▲]

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See detailThe influence of COMT on the neural substrates of short-term memory in normal aging
Manard, Marine ULg; Salmon, Eric ULg; Collette, Fabienne ULg

Conference (2016, September 02)

Working memory dopaminergic modulation is generally expressed in healthy aging by an advantage for carriers of the Met allele at behavioral and brain activity levels. However, most tasks used did not ... [more ▼]

Working memory dopaminergic modulation is generally expressed in healthy aging by an advantage for carriers of the Met allele at behavioral and brain activity levels. However, most tasks used did not allow to easily disentangle the contribution of maintenance and manipulation processes. We explored the effect of COMT genotype on the maintenance process using a Sternberg memory task varying the amount of information presented, in young and older homozygous carriers for the Val and Met alleles of the COMT gene. Although no clear behavioral difference was observed between groups, patterns of cerebral activity indicate difficulties for Met older individuals to maintain stable representations. These results will be discussed in terms of dopaminergic contribution to stability/flexibility of cognitive processes during aging. [less ▲]

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See detailEffects of aging on task- and stimulus-related cerebral attention networks
Kurth, Sophie ULg; Majerus, Steve ULg; Bastin, Christine ULg et al

in Neurobiology of Aging (2016), 44

Interactions between a dorsal attention (DAN) and a ventral attention cerebral network (VAN) have been reported in young participants during attention or short term memory (STM) tasks. Since it remains an ... [more ▼]

Interactions between a dorsal attention (DAN) and a ventral attention cerebral network (VAN) have been reported in young participants during attention or short term memory (STM) tasks. Since it remains an under-investigated question, age effects on DAN and VAN activity and their functional balance were explored during performance of a STM task. Older and young groups showed similar behavioral patterns of results. At the cerebral level, DAN activation increased as a function of increasing STM load in both groups, suggesting preserved activity in DAN during healthy aging. Age-related over-recruitment in regions of the DAN in the higher task load raised the question of compensation attempt versus less efficient use of neural resources in older adults. Lesser decrease of VAN activation with increasing load and decreased stimulus-driven activation in the VAN, especially in the higher load, in older participants suggested age-related reduced response in the VAN. However, functional connectivity measures showed that VAN was still functionally connected to the DAN in older participants. [less ▲]

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See detailThe influence of COMT on the neural substrates of short-term memory in normal aging
Collette, Fabienne ULg; Manard, Marine ULg; Salmon, Eric ULg

Conference (2016, July 21)

Working memory dopaminergic modulation is generally expressed in healthy aging by an advantage for carriers of the Met allele at behavioral and brain activity levels. However, most tasks used did not ... [more ▼]

Working memory dopaminergic modulation is generally expressed in healthy aging by an advantage for carriers of the Met allele at behavioral and brain activity levels. However, most tasks used did not allow to easily disentangle the contribution of maintenance and manipulation processes. We explored the effect of COMT genotype on the maintenance process using a Sternberg memory task varying the amount of information presented, in young and older homozygous carriers for the Val and Met alleles of the COMT gene. Although no clear behavioral difference was observed between groups, patterns of cerebral activity indicate difficulties for Met older individuals to maintain stable representations. These results will be discussed in terms of dopaminergic contribution to stability/flexibility of cognitive processes during aging. [less ▲]

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See detailRecollection versus familiarity in normal aging and in mild cognitive impairment: Impact of test format.
Simon, Jessica ULg; Gilsoul, Jessica ULg; SALMON, Eric ULg et al

Poster (2016, July 18)

The aim of this study was to investigate the impact of test format on recollection and familiarity in normal aging and in MCI. Seventy young participants, 65 younger-old, 53 older-old, and 13 MCIs were ... [more ▼]

The aim of this study was to investigate the impact of test format on recollection and familiarity in normal aging and in MCI. Seventy young participants, 65 younger-old, 53 older-old, and 13 MCIs were presented with forced-choice and yes/no visual recognition memory tasks with the Remember/Know/Guess paradigm. The young people had better recognition performance than younger-old, who performed better than older-old and MCIs. Recollection and familiarity declined progressively in healthy aging. In MCI, recollection was more affected than familiarity, but patients demonstrated a more liberal use of familiarity. Finally, test format did not influence strongly the results. Young people used recollection more often in the forced-choice task compared to the yes/no task. [less ▲]

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See detailDisrupted interaction between self and memory in patients with Alzheimer’s disease
Genon, Sarah ULg; Salmon, Eric ULg; Collette, Fabienne ULg et al

Conference (2016, July)

In humans, self and memory processes interact as evidenced by the self reference (SRE) and self reference recollection effects (SRRE). However, in patients with Alzheimer’s disease (AD), this relationship ... [more ▼]

In humans, self and memory processes interact as evidenced by the self reference (SRE) and self reference recollection effects (SRRE). However, in patients with Alzheimer’s disease (AD), this relationship can be disrupted. This was evidenced by impaired SRE and SRRE in AD for recognition of adjectives previously judged for self-relevance, as well as recall of names of people previously linked to the self. For both materials, a qualitative impairment of the recollective experience for the self-related items was also observed in AD. A neuroimaging approach suggested that reduced SRE is related to decreased grey matter volume in the lateral prefrontal cortex (lPFC). Thus, retrieval of recent self-related memories is impaired in relation to altered high-order processes in lPFC in AD. [less ▲]

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See detailSubstrats neuronaux de l'encodage non réussi dans le vieillissement
François, Sarah ULg; Angel, Lucie; Salmon, Eric ULg et al

Conference (2016, May 27)

Objectifs En utilisant l'IRM fonctionnelle, nous nous sommes intéressés à l'effet de l'âge sur les substrats neuronaux de l'encodage non réussi – l'activation à l'encodage pour les items oubliés par la ... [more ▼]

Objectifs En utilisant l'IRM fonctionnelle, nous nous sommes intéressés à l'effet de l'âge sur les substrats neuronaux de l'encodage non réussi – l'activation à l'encodage pour les items oubliés par la suite. Méthodologie Dans un scanner IRM, nous avons soumis des volontaires (20 jeunes et 19 âgés) à une tâche de mémoire épisodique avec consignes d'encodage incident. Durant celle-ci, des dessins d'objets en noir et blanc leur étaient présentés. Il leur était demandé d'effectuer un jugement de taille sur ces objets. Ensuite, toujours dans le scanner, les objets de la phase d'encodage ainsi que de nouveaux objets leurs étaient présentés afin d'évaluer leur reconnaissance de ceux-ci. Pour ce faire, les volontaires effectuaient un jugement de Recollection/Familiarité/Nouveauté. Résultats Les résultats comportementaux montrent une recollection altérée mais une familiarité préservée chez nos volontaires âgés. L'analyse des résultats IRM a été effectuée selon un design évènementiel (SPM8), dans lequel nous avons comparé les aires cérébrales activées à l'encodage pour les items qui n'ont pas été reconnus ultérieurement et pour ceux qui ont donné lieu à un jugement de recollection (p<.001 non-corrigé). Dans les deux groupes, un pattern d'activation correspondant au réseau du mode par défaut (RMD). Chez les volontaires âgés, les résultats ont également mis en évidence une activation supplémentaire du réseau attentionnel fronto-pariétal. Ensuite, le contraste entre les activations pour les items qui n'ont pas été reconnus ultérieurement et ceux qui ont donné lieu à un jugement de familiarité a aussi mis en évidence des régions du RMD, mais dans une moindre mesure. En effet, les activités communes aux deux groupes d'âge n'ont montré qu'une activation du précuneus. Discussion Comparé à la recollection, l'oubli d'informations semble associé, à l'encodage, à un recrutement accru du RMD qui pourrait refléter une incapacité à mettre en place des processus d'encodage efficaces, à la fois chez les jeunes adultes et les adultes plus âgés. De plus, l'activation supplémentaire du réseau fronto-pariétal chez ces derniers pourrait indiquer un fonctionnement moins différencié des réseaux cérébraux associés à l'encodage en mémoire. Lorsque l'on compare l'oubli d'informations à la familiarité, l'activation moindre du RMD pourrait suggérer qu'un certain niveau d'activation du RMD (et donc la présence de pensées étrangères à la tâche) n'empêche pas forcément toute reconnaissance sur base d'un sentiment de familiarité. [less ▲]

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See detailSubstrats cérébraux du contrôle proactif et réactif dans le vieillissement non pathologique
Manard, Marine ULg; François, Sarah ULg; Salmon, Eric ULg et al

Poster (2016, May 27)

Les recherches sur le contrôle cognitif proposent l’apparition d’un déclin lié à l’âge dans les capacités de contrôle proactif (forme anticipatoire de contrôle comportemental) alors que le contrôle ... [more ▼]

Les recherches sur le contrôle cognitif proposent l’apparition d’un déclin lié à l’âge dans les capacités de contrôle proactif (forme anticipatoire de contrôle comportemental) alors que le contrôle réactif (forme réactionnelle à la détection d’un conflit) semble rester intact [1]. Ces deux formes de contrôle ont été associées à des aires cérébrales différentes [2], cependant peu d’études ont étudié les effets de l’âge sur les régions cérébrales sous-tendant chacun de ces deux types de contrôle. Pour ce faire, une version adaptée de la tâche de Stroop a été administrée à 16 jeunes (18-30 ans) et 16 adultes (60-75 ans) en IRM fonctionnelle. Cette version de la tâche variait la quantité d’items interférents, permettant la création de trois contextes (Mostly Congruent « MC », Mostly Incongruent « MI » et Neutre) favorisant respectivement la mise en place des deux types de contrôle (réactif = congruent / proactif = incongruent). Les analyses ont été réalisées avec SPM8 (p<.001 non-corrigé). Les résultats comportementaux révèlent un traitement plus rapide de l’interférence dans le contexte « MI » que « MC » pour les jeunes adultes uniquement. Au niveau cérébral, le traitement de l’interférence en MI semble associé à une diminution d’activité (surtout à droite) dans les régions frontales et temporales chez les volontaires âgés par rapport aux plus jeunes, alors qu’en MC, les âgés montrent une augmentation d’activité bilatérale au niveau frontal. Ainsi, les résultats comportementaux montrent que les adultes âgés semblent avoir plus de difficultés à implémenter un contrôle proactif (associé à une diminution d’activité) que les jeunes dans les régions sous-tendant la performance à cette tâche. Cependant, le recrutement supplémentaire de régions frontales observé lors du contexte MC postulé pour favoriser le contrôle réactif, suggère la présence de mécanismes de compensation. Pour conclure, le vieillissement semble affecter de manière différentielle l’activité des régions cérébrales sous-tendant les différents types de contrôle. [less ▲]

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See detailThe influence of COMT single nucleotide polymorphism (rs4680) on the neural substrates of working memory representations maintenance in healthy aging
Manard, Marine ULg; François, Sarah ULg; Bahri, Mohamed Ali ULg et al

Poster (2016, May 10)

The COMT val108/158met polymorphism was associated to the dopaminergic modulation in the brain, and therefore stimulated research on its influence for cognitive functioning and particularly working memory ... [more ▼]

The COMT val108/158met polymorphism was associated to the dopaminergic modulation in the brain, and therefore stimulated research on its influence for cognitive functioning and particularly working memory. First, a general advantage of carrying the met allele was reported. However, many studies used tasks that did not allow efficiently assessing the contribution of manipulation and maintenance processes in working memory, leading to divergent results, in both young and older populations, resulting in debates about the exact phenotypic effect of the COMT polymorphism. Using fMRI, this study was designed to assess the potential effect of the COMT polymorphism on age-related differences in working memory representations maintenance abilities (Sternberg paradigm). Partial Least Squares method was used to determine the brain-behavior correlations at low, intermediate, and high cognitive demands among young and older groups, homozygous for the val or for the met allele. First, young val/val showed some disadvantages at brain and behavioral level compared to their m/m counterparts. However, in older adults subgroups, the m/m participants tended to show greater age-related difference (when compared to younger adults with similar genotype), suggesting an advantage in carrying the val allele when dopamine signaling is not at optimal efficiency (optimal: young/middle adulthood vs suboptimal: childhood or older ages). These results will be discussed in regard to compensating theories and dopaminergic models accounting for the potential effect of COMT polymorphism on stability/flexibility abilities. [less ▲]

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See detailRecollection versus familiarity in normal aging and in mild cognitive impairment: Impact of test format
Gilsoul, Jessica ULg; Simon, Jessica ULg; SALMON, Eric ULg et al

Poster (2016, March 18)

Objectives. Memory retrieval typically involves a combination of recollection and familiarity. However, test format can promote one or the other process (Norman & O’Reilly, 2003). The aim of this study ... [more ▼]

Objectives. Memory retrieval typically involves a combination of recollection and familiarity. However, test format can promote one or the other process (Norman & O’Reilly, 2003). The aim of this study was to investigate the impact of test format on recollection and familiarity in normal aging and in mild cognitive impairment (MCI). Methods. Seventy young participants (18-30 years), 65 “younger-old” (55- 69 years), 53 “older-old” (70-85 years), and 13 MCIs (55-82 years) were enrolled. In the “forced-choice” task, they had to recognize which picture, among three, was presented during the encoding stage. In the “yes/no” task, they had to judge whether each item, successively presented, was previously seen or not. In each task, they had to give a “Remember/Know/Guess” judgment. Results. Group × Format repeated measures ANOVAs revealed that young people had better recognition performance (d’) than “younger-old”, which were better than “older-old” and MCIs. Moreover, young people used familiarity more accurately than both groups of old participants and MCIs, with MCIs being equivalent to “younger-old” and “older-old”. However, MCIs displayed a high rate of familiarity-based false alarms. The resort to recollection decreased with age and in MCIs. Finally, Group × Format interaction revealed that young people (but not the other groups) could use recollection more often in the “forcedchoice” task compared to the “yes/no” task. Conclusions. Recollection and familiarity decline progressively in healthy aging. In MCI, recollection is more affected than familiarity, but patients demonstrated a more liberal use of familiarity. Finally, test format did not influence strongly the results. [less ▲]

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See detailNeural bases of subsequent forgetting in young and older adults
François, Sarah ULg; Angel, Lucie; Salmon, Eric ULg et al

Poster (2016, March 17)

Objectives Using functional MRI, we looked into the age-related difference in the neural underpinnings of subsequent forgetting - cerebral activation at encoding for items that are later forgotten ... [more ▼]

Objectives Using functional MRI, we looked into the age-related difference in the neural underpinnings of subsequent forgetting - cerebral activation at encoding for items that are later forgotten. Methods In an MRI scanner, during an incidental encoding phase, participants (20 young and 19 older adults) were presented with black-and-white drawings of objects. They were instructed to perform a size judgement on the depicted objects. Then, still in the scanner, the volunteers' memory for the objects was tested by showing them pictures shown previously along with new ones and asking them to make a Remember/Know/New judgement. Results Behaviourally, older participants showed decreased recollection, but intact familiarity at recognition. In an event-related design (SPM8), we compared cerebral areas activated at encoding for items subsequently forgotten compared to those leading to recollection (p<.001 uncorrected). In both groups, a pattern of activation consistent with the default-mode network (DMN) was found. Furthermore, results pointed out to additional activations in the frontoparietal control network in older adults. Also, contrasting activations for items subsequently forgotten with those leading to familiarity revealed activations in DMN areas. In young adults, these activations were limited to the posterior cingulate cortex. Conclusions The forgetting of information appears to be associated with a higher recruitment of the DMN, which might reflect disengagement from encoding-supportive processes, both in young and older participants. Moreover, the additional fronto-parietal activity found in the older group could indicate that their failure to recollect the pictures was related to inefficient encoding mechanisms, in addition to disengagement from the task. [less ▲]

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See detailSuccessful episodic memory encoding in ageing: an fMRI study
François, Sarah ULg; Angel, Lucie; Salmon, Eric ULg et al

Poster (2016, January 25)

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See detailRelationship between grey matter integrity and executive abilities in aging
Manard, Marine ULg; Bahri, Mohamed Ali ULg; Salmon, Eric ULg et al

in Brain Research (2016), 1642

This cross-sectional study was designed to investigate grey matter changes that occur in healthy aging and the relationship between grey matter characteristics and executive functioning. Thirty-six young ... [more ▼]

This cross-sectional study was designed to investigate grey matter changes that occur in healthy aging and the relationship between grey matter characteristics and executive functioning. Thirty-six young adults (18 to 30 years old) and 43 seniors (60 to 75 years old) were included. A general executive score was derived from a large battery of neuropsychological tests assessing three major aspects of executive functioning (inhibition, updating and shifting). Age-related grey matter changes were investigated by comparing young and older adults using voxel-based morphometry and voxel-based cortical thickness methods. A widespread difference in grey matter volume was found across many brain regions, whereas cortical thinning was mainly restricted to central areas. Multivariate analyses showed age-related changes in relatively similar brain regions to the respective univariate analyses but appeared more limited. Finally, in the older adult sample, a significant relationship between global executive performance and decreased grey matter volume in anterior (i.e. frontal, insular and cingulate cortex) but also some posterior brain areas (i.e. temporal and parietal cortices) as well as subcortical structures was observed. Results of this study highlight the distribution of age-related effects on grey matter volume and show that cortical atrophy does not appear primarily in “frontal” brain regions. From a cognitive viewpoint, age-related executive functioning seems to be related to grey matter volume but not to cortical thickness. Therefore, our results also highlight the influence of methodological aspects (from preprocessing to statistical analysis) on the pattern of results, which could explain the lack of consensus in literature. [less ▲]

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See detailCorrelation between resting state fMRI total neuronal activity and PET metabolism in healthy controls and patients with disorders of consciousness
Soddu, Andrea ULg; Gomez, Francisco; Heine, Lizette ULg et al

in Brain and Behavior (2016)

Introduction: The mildly invasive 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a well-established imaging technique to measure ‘resting state’ cerebral metabolism. This technique made ... [more ▼]

Introduction: The mildly invasive 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) is a well-established imaging technique to measure ‘resting state’ cerebral metabolism. This technique made it possible to assess changes in metabolic activity in clinical applications, such as the study of severe brain injury and disorders of consciousness. Objective: We assessed the possi- bility of creating functional MRI activity maps, which could estimate the rela- tive levels of activity in FDG-PET cerebral metabolic maps. If no metabolic absolute measures can be extracted, our approach may still be of clinical use in centers without access to FDG-PET. It also overcomes the problem of recogniz- ing individual networks of independent component selection in functional mag- netic resonance imaging (fMRI) resting state analysis. Methods: We extracted resting state fMRI functional connectivity maps using independent component analysis and combined only components of neuronal origin. To assess neu- ronality of components a classification based on support vector machine (SVM) was used. We compared the generated maps with the FDG-PET maps in 16 healthy controls, 11 vegetative state/unresponsive wakefulness syndrome patients and four locked-in patients. Results: The results show a significant similarity with q = 0.75  0.05 for healthy controls and q = 0.58  0.09 for vegetative state/unresponsive wakefulness syndrome patients between the FDG- PET and the fMRI based maps. FDG-PET, fMRI neuronal maps, and the conjunction analysis show decreases in frontoparietal and medial regions in vegetative patients with respect to controls. Subsequent analysis in locked-in syndrome patients produced also consistent maps with healthy controls. Conclusions: The constructed resting state fMRI functional connectivity map points toward the possibility for fMRI resting state to estimate relative levels of activity in a metabolic map. [less ▲]

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