fMRI evidence for competition between task-related and stimulus-related attention in verbal short-term memory.
Conference (2010, September)Detailed reference viewed: 9 (1 ULg)
Impact de la longueur des énoncés et de la fréquence lexicale sur la compréhension d’énoncés chez des enfants
Leclercq, Anne-Lise ; Majerus, Steve ; Maillart, Christelle
Conference (2010, July 06)
Introduction En psychologie cognitive, plusieurs modèles théoriques considèrent que le système de traitement de l’information humain a une capacité limitée (notamment, Just & Varma, 2007). L’efficacité ... [more ▼]
Introduction En psychologie cognitive, plusieurs modèles théoriques considèrent que le système de traitement de l’information humain a une capacité limitée (notamment, Just & Varma, 2007). L’efficacité lors d’activités recrutant un grand nombre de traitements cognitifs serait dépendante de la quantité de ressources disponibles pour les réaliser. En particulier, l’activité de compréhension d’énoncés nécessite la réalisation rapide et quasi simultanée d’un grand nombre de traitements, dont l’analyse morphosyntaxique à proprement parler, mais également le décodage phonologique et l’accès lexical. En outre, d’autres processus cognitifs interviennent, comme l’attention portée à la tâche ou la mémoire de travail qui permet la coordination entre le traitement de l’énoncé et le stockage des produits partiels de celui-ci. Selon le modèle de compréhension d’énoncés de Just & Carpenter (1992), les ressources disponibles doivent être réparties entre le stockage des éléments traités et l’analyse et l’intégration des éléments à traiter. Selon ces auteurs, certaines opérations sont plus coûteuses que d’autres. Par exemple, le traitement de lexèmes de basse fréquence lexicale serait plus coûteux que le traitement de lexèmes fréquents, car le niveau d’activation de base de leurs représentations lexicales serait inférieur à celui des derniers. De même, comme chaque élément à traiter consume des ressources, les ressources cognitives disponibles pour le traitement de chaque morphème sont proportionnellement moindres dans des énoncés longs que dans des énoncés courts. Ce nécessaire compromis lors du partage des ressources entre les opérations de stockage et de traitement peut donc se traduire par une chute des performances en compréhension d’énoncés, soit par oubli des premiers éléments traités, soit par manque de ressources pour traiter les derniers éléments présentés. Objectif Cette étude évalue l’impact de la longueur des énoncés et de la fréquence lexicale des lexèmes sur les performances en compréhension d’énoncés d’enfants de 4, 6, 8 et 10 ans. Méthodologie Participants : Enfants de 4, 6 et 8 ans (N=30 dans chaque groupe) et 15 enfants de 10 ans Tâche : Compréhension d’énoncés présentés oralement (structure = S + V transitif + COD + Proposition relative sujet avec verbe intransitif). Manipulation de la fréquence lexicale (4 niveaux) et de la longueur des énoncés par ajout d’éléments redondants (4 niveaux) Résultats Les effets de fréquence lexicale et de longueur se marquent en termes de réponses correctes de 4 à 6 ans, et en termes de rapidité de réponse de 6 à 10 ans. Conclusions La longueur des énoncés et la fréquence lexicale des termes utilisés sont des facteurs de complexité dans la compréhension d’énoncés, qui se manifestent par un échec de la compréhension chez les enfants les plus jeunes, et par un allongement du temps de traitement chez les enfants plus âgés. [less ▲]Detailed reference viewed: 248 (16 ULg)
Impact of phonological complexity on verbal short-term memory performance in children with SLI
Leclercq, Anne-Lise ; Maillart, Christelle ; Majerus, Steve
Poster (2010, June 26)Detailed reference viewed: 61 (6 ULg)
Impact of morphosyntactic complexity in sentence comprehension in children with SLI
Leclercq, Anne-Lise ; Majerus, Steve ; et al
Poster (2010, June)Detailed reference viewed: 97 (9 ULg)
Using phenomenology and mindset induction to assess the prospective function of mind-wandering
Stawarczyk, David ; Majerus, Steve ; D'Argembeau, Arnaud
Poster (2010, May 28)
A notable feature of the human cognitive apparatus resides in its propensity to spontaneously generate thoughts uncoupled from the “here and now”. An important function of these cognitions, often referred ... [more ▼]
A notable feature of the human cognitive apparatus resides in its propensity to spontaneously generate thoughts uncoupled from the “here and now”. An important function of these cognitions, often referred to as mind-wandering, might be to create and/or update scripts, schemata, and future plans in long-term memory. In this study, we investigated this hypothesis by examining whether priming personal projects influenced the occurrence and characteristics of mind-wandering episodes during a subsequent, unrelated cognitive task, as assessed with an experience sampling method. We found that inducing particular mindsets that were related to personal goals (i.e., writing an essay about one’s personal projects) in comparison to a control baseline condition (i.e., writing an essay about a familiar itinerary) increased the number of future-oriented mind-wandering reports while participants performed the Sustained Attention to Response Task (SART). Furthermore, participants judged most of these thoughts as having a future-oriented function (i.e., they were related to planning, decision making, or reevaluating situations). Finally, as behavioral validation of participants’ subjective reports, we found that mind-wandering was positively linked with intra-individual variability (IIV) in response times, whereas reports of being concentrated on the SART were negatively linked with IIV. These data support the view that an important function of mind-wandering resides in the anticipation and planning of the future. [less ▲]Detailed reference viewed: 61 (1 ULg)
Evidence for atypical categorical speech perception in Williams syndrome.
Majerus, Steve ; Poncelet, Martine ; et al
Conference (2010, May 27)Detailed reference viewed: 8 (0 ULg)
Les relations entre la mémoire à court terme verbale et troubles du langage.
Conference (2010, March 27)Detailed reference viewed: 2 (1 ULg)
The impact of emotional valence on short-term memory word list recall : Evidence for a conjoined influence of semantic long-term memory and attentional factors.
Majerus, Steve ; D'Argembeau, Arnaud
Conference (2010, February 12)Detailed reference viewed: 8 (0 ULg)
The relationship between serial order STM and vocabulary development: a longitudinal study.
Leclercq, Anne-Lise ; Majerus, Steve
in Developmental Psychology (2010), 46(2), 417-427Detailed reference viewed: 167 (44 ULg)
Traitement perceptif et phonologique atypique dans le syndrome de Williams?
Scientific conference (2010)Detailed reference viewed: 6 (0 ULg)
An fMRI region-based investigation of cognitive processes involved in the item-method directed forgetting
Bastin, Christine ; Feyers, Dorothée ; Salmon, Eric et al
Conference (2010)Detailed reference viewed: 12 (4 ULg)
Assessment and detection of pain in noncommunicative severely brain-injured patients.
Schnakers, Caroline ; Chatelle, Camille ; Majerus, Steve et al
in Expert Review of Neurotherapeutics (2010), 10(11), 1725-31
Detecting pain in severely brain-injured patients recovering from coma represents a real challenge. Patients with disorders of consciousness are unable to consistently or reliably communicate their ... [more ▼]
Detecting pain in severely brain-injured patients recovering from coma represents a real challenge. Patients with disorders of consciousness are unable to consistently or reliably communicate their feelings and potential perception of pain. However, recent studies suggest that patients in a minimally conscious state can experience pain to some extent. Pain monitoring in these patients is hence of medical and ethical importance. In this article, we will focus on the possible use of behavioral scales for the assessment and detection of pain in noncommunicative patients. [less ▲]Detailed reference viewed: 64 (3 ULg)
The commonality of neural networks for verbal and visual short-term memory.
Majerus, Steve ; D'Argembeau, Arnaud ; Martinez Perez, Trecy et al
in Journal of Cognitive Neuroscience (2010), 22(11), 2570-2593
Although many neuroimaging studies have considered verbal and visual short-term memory (STM) as relying on neurally segregated short-term buffer systems, the present study explored the existence of shared ... [more ▼]
Although many neuroimaging studies have considered verbal and visual short-term memory (STM) as relying on neurally segregated short-term buffer systems, the present study explored the existence of shared neural correlates supporting verbal and visual STM. We hypothesized that networks involved in attentional and executive processes, as well as networks involved in serial order processing, underlie STM for both verbal and visual list information, with neural specificity restricted to sensory areas involved in processing the specific items to be retained. Participants were presented sequences of nonwords or unfamiliar faces, and were instructed to maintain and recognize order or item information. For encoding and retrieval phases, null conjunction analysis revealed an identical fronto-parieto-cerebellar network comprising the left intraparietal sulcus, bilateral dorsolateral prefrontal cortex, and the bilateral cerebellum, irrespective of information type and modality. A network centered around the right intraparietal sulcus supported STM for order information, in both verbal and visual modalities. Modality-specific effects were observed in left superior temporal and mid-fusiform areas associated with phonological and orthographic processing during the verbal STM tasks, and in right hippocampal and fusiform face processing areas during the visual STM tasks, wherein these modality effects were most pronounced when storing item information. The present results suggest that STM emerges from the deployment of modality-independent attentional and serial ordering processes toward sensory networks underlying the processing and storage of modality-specific item information. [less ▲]Detailed reference viewed: 209 (72 ULg)
Neural networks involved in self-judgement in young and elderly adults
Feyers, Dorothée ; Collette, Fabienne ; D'Argembeau, Arnaud et al
in NeuroImage (2010)
Recent studies have shown that both young and elderly subjects activate the ventromedial prefrontal cortex (VMPFC) when they make self-referential judgements. However, the VMPFC might interact with ... [more ▼]
Recent studies have shown that both young and elderly subjects activate the ventromedial prefrontal cortex (VMPFC) when they make self-referential judgements. However, the VMPFC might interact with different brain regions during self-referencing in the two groups. In this study, based on data from Ruby et al (2009), we have explored this issue using psychophysiological interaction analyses. Young and elderly participants had to judge adjectives describing personality traits in reference to the self versus a close friend or relative (the other), taking either a first-person or a third-person perspective. The physiological factor was the VMPFC activity observed in all participants during self judgement, and the psychological factor was the self versus other referential process. The main effect of first-person perspective in both groups revealed that the VMPFC was coactivated with the left parahippocampal gyrus and the precuneus for self versus other judgments. The main effect of age showed a stronger correlation between activity in the VMPFC and the lingual gyrus in young compared to elderly subjects. Finally, in the interaction, the VMPFC was specifically co-activated with the orbitofrontal gyrus and the precentral gyrus when elderly subjects took a first-person perspective for self judgements. No significant result was observed for the interaction in young subjects. These findings show that, although the VMPFC is engaged by both young and older adults when making self-referential judgements, this brain structure interacts differently with other brain regions as a function of age and perspective. These differences might reflect a tendency by older people to engage in more emotional/social processing than younger adults when making self-referential judgements with a first-person perspective [less ▲]Detailed reference viewed: 52 (16 ULg)
Visual fixation in the vegetative state: an observational case series PET study.
Bruno, Marie-Aurélie ; Vanhaudenhuyse, Audrey ; Schnakers, Caroline et al
in BMC Neurology (2010), 10
BACKGROUND: Assessment of visual fixation is commonly used in the clinical examination of patients with disorders of consciousness. However, different international guidelines seem to disagree whether ... [more ▼]
BACKGROUND: Assessment of visual fixation is commonly used in the clinical examination of patients with disorders of consciousness. However, different international guidelines seem to disagree whether fixation is compatible with the diagnosis of the vegetative state (i.e., represents "automatic" subcortical processing) or is a sufficient sign of consciousness and higher order cortical processing. METHODS: We here studied cerebral metabolism in ten patients with chronic post-anoxic encephalopathy and 39 age-matched healthy controls. Five patients were in a vegetative state (without fixation) and five presented visual fixation but otherwise showed all criteria typical of the vegetative state. Patients were matched for age, etiology and time since insult and were followed by repeated Coma Recovery Scale-Revised (CRS-R) assessments for at least 1 year. Sustained visual fixation was considered as present when the eyes refixated a moving target for more than 2 seconds as defined by CRS-R criteria. RESULTS: Patients without fixation showed metabolic dysfunction in a widespread fronto-parietal cortical network (with only sparing of the brainstem and cerebellum) which was not different from the brain function seen in patients with visual fixation. Cortico-cortical functional connectivity with visual cortex showed no difference between both patient groups. Recovery rates did not differ between patients without or with fixation (none of the patients showed good outcome). CONCLUSIONS: Our findings suggest that sustained visual fixation in (non-traumatic) disorders of consciousness does not necessarily reflect consciousness and higher order cortical brain function. [less ▲]Detailed reference viewed: 27 (4 ULg)
Modulation of medial prefrontal and inferior parietal cortices when thinking about past, present, and future selves.
D'Argembeau, Arnaud ; Stawarczyk, David ; Majerus, Steve et al
in Social Neuroscience (2010), 5
Recent functional neuroimaging studies have shown that reflecting on representations of the present self versus temporally distant selves is associated with higher activity in the medial prefrontal cortex ... [more ▼]
Recent functional neuroimaging studies have shown that reflecting on representations of the present self versus temporally distant selves is associated with higher activity in the medial prefrontal cortex (MPFC). In the current fMRI study, we investigated whether this effect of temporal perspective is symmetrical between the past and future. The main results revealed that the MPFC showed higher activity when reflecting on the present self than when reflecting on past and future selves, with no difference between past and future selves. Temporal perspective also modulated activity in the right inferior parietal cortex but in the opposite direction, activity in this brain region being higher when reflecting on past and future selves relative to the present self (with again no difference between past and future selves). These findings show that differences in brain activity when thinking about current versus temporally distant selves are symmetrical between the past and the future. It is suggested that by processing degrees of self-relatedness, the MPFC might sustain the process of identifying oneself with current representations of the self, whereas the right inferior parietal cortex might be involved in distinguishing the present self from temporally distant selves. [less ▲]Detailed reference viewed: 195 (15 ULg)
The neural basis of personal goal processing when envisioning future events
D'Argembeau, Arnaud ; Stawarczyk, David ; Majerus, Steve et al
in Journal of Cognitive Neuroscience (2010), 22
Abstract Episodic future thinking allows humans to mentally simulate virtually infinite future possibilities, yet this device is fundamentally goal-directed and should not be equated with fantasizing or ... [more ▼]
Abstract Episodic future thinking allows humans to mentally simulate virtually infinite future possibilities, yet this device is fundamentally goal-directed and should not be equated with fantasizing or wishful thinking. The purpose of this functional magnetic resonance imaging study was to investigate the neural basis of such goal-directed processing during future-event simulation. Participants were scanned while they imagined future events that were related to their personal goals (personal future events) and future events that were plausible but unrelated to their personal goals (nonpersonal future events). Results showed that imaging personal future events elicited stronger activation in ventral medial prefrontal cortex (MPFC) and posterior cingulate cortex (PCC) compared to imaging nonpersonal future events. Moreover, these brain activations overlapped with activations elicited by a second task that assessed semantic self-knowledge (i.e., making judgments on one's own personality traits), suggesting that ventral MPFC and PCC mediate self-referential processing across different functional domains. It is suggested that these brain regions may support a collection of processes that evaluate, code, and contextualize the relevance of mental representations with regard to personal goals. The implications of these findings for the understanding of the function instantiated by the default network of the brain are also discussed. [less ▲]Detailed reference viewed: 171 (21 ULg)
The nociception coma scale: A new tool to assess nociception in disorders of consciousness.
Schnakers, Caroline ; Chatelle, Camille ; Vanhaudenhuyse, Audrey et al
in Pain (2010), 148
Assessing behavioral responses to nociception is difficult in severely brain-injured patients recovering from coma. We here propose a new scale developed for assessing nociception in vegetative (VS) and ... [more ▼]
Assessing behavioral responses to nociception is difficult in severely brain-injured patients recovering from coma. We here propose a new scale developed for assessing nociception in vegetative (VS) and minimally conscious (MCS) coma survivors, the Nociception Coma Scale (NCS), and explore its concurrent validity, inter-rater agreement and sensitivity. Concurrent validity was assessed by analyzing behavioral responses of 48 post-comatose patients to a noxious stimulation (pressure applied to the fingernail) (28 VS and 20 MCS; age range 20-82years; 17 of traumatic etiology). Patients' were assessed using the NCS and four other scales employed in non-communicative patients: the 'Neonatal Infant Pain Scale' (NIPS) and the 'Faces, Legs, Activity, Cry, Consolability' (FLACC) used in newborns; and the 'Pain Assessment In Advanced Dementia Scale' (PAINAD) and the 'Checklist of Non-verbal Pain Indicators' (CNPI) used in dementia. For the establishment of inter-rater agreement, fifteen patients were concurrently assessed by two examiners. Concurrent validity, assessed by Spearman rank order correlations between the NCS and the four other validated scales, was good. Cohen's kappa analyses revealed a good to excellent inter-rater agreement for the NCS total and subscore measures, indicating that the scale yields reproducible findings across examiners. Finally, a significant difference between NCS total scores was observed as a function of diagnosis (i.e., VS or MCS). The NCS constitutes a sensitive clinical tool for assessing nociception in severely brain-injured patients. This scale constitutes the first step to a better management of patients recovering from coma. [less ▲]Detailed reference viewed: 80 (9 ULg)
Das verbale Kurzzeitgedächtnis als Produkt der Interaktionen zwischen Aufmerksamkeitskapazitäten, Sequenzverarbeitung und Aktivierung des Sprachsystems.
in Psychologische Rundschau : Ueberblick Uber die Fortschritte der Psychologie in Deutschland, Oesterreich, und der Schweiz (2010), 61Detailed reference viewed: 36 (3 ULg)
Les multiples determinants de la mémoire à court terme verbale : implications théoriques et évaluatives
in Développements (2010), 4Detailed reference viewed: 164 (29 ULg)