Do common principles underlie the representation of order in STM and numerical judgment tasks?
Attout, Lucie ; Majerus, Steve
Conference (2012, March 29)
Although many studies have explored magnitude effects in numerical cognition, the representation of order information has received only limited interest. We explored the hypothesis that common abstract ... [more ▼]
Although many studies have explored magnitude effects in numerical cognition, the representation of order information has received only limited interest. We explored the hypothesis that common abstract ordinal representations underlie the representation of order information across different domains. We tested this hypothesis by determining the similarity of distance effects in short-term memory (STM) order probe recognition (did ‘8’ occur before ‘5’ in the list ‘3, 6, 5, 4, 8, 7’ presented a few seconds ago?) and in order judgment tasks (does ‘1’ occur before ‘2’), both numerical and alphabetical stimuli were used. In numerical cognition, adjacent numbers are typically judged more slowly than more distant numbers. In fifty healthy adults, we observed significant distance effects across all tasks: in the order judgment tasks, adjacent numbers/letters were judged more slowly than more distant numbers/letters; in the STM tasks, order recognition was slowed for stimuli stemming from adjacent positions in the STM list as compared to stimuli stemming from more distant positions. Regression slopes for distance effects were identical across the different tasks and conditions. Furthermore, the size of distance effects correlated significantly across tasks, except for the order judgment task with numerical stimuli. We will discuss the implications of these results for a hypothetical common representational system of order information in STM and numerical cognition. [less ▲]Detailed reference viewed: 44 (3 ULg)
Mémoire de travail / mémoire à court terme : aspects théoriques récents et implications pour l'évaluation et la rééducation.
Scientific conference (2012, March 24)Detailed reference viewed: 18 (0 ULg)
Déficits de mémoire verbale à court-terme pour l’ordre sériel chez des enfants dyslexiques
Martinez Perez, Trecy ; Majerus, Steve ; Poncelet, Martine
Poster (2012, March 16)Detailed reference viewed: 178 (13 ULg)
Evidence for common principles underlying representation of order in short-term memory and numerical cognition.
Attout, Lucie ; Majerus, Steve
Conference (2012, March)Detailed reference viewed: 34 (0 ULg)
Neurophysiological indices of top-down attentional processing in minimally conscious patients : an ERP study.
; ; et al
Conference (2012, March)Detailed reference viewed: 9 (0 ULg)
The problem of assessing consciousness in brain-damaged patients with aphasia
; ; et al
Conference (2012, March)Detailed reference viewed: 11 (0 ULg)
DISSOCIATING SHORT-TERM MEMORY AND LANGUAGE IMPAIRMENT: THE IMPORTANCE OF ITEM AND SERIAL ORDER INFORMATION
Attout, Lucie ; VAN DER KAA, Marie-Anne ; GEORGE, Mercédès et al
in Aphasiology (2012), 26(3-4), 355-382
BACKGROUND: Selective verbal short-term memory (STM) deficits are rare, and when they appear, they are often associated with a history of aphasia, raising doubts about the selectivity of these deficits ... [more ▼]
BACKGROUND: Selective verbal short-term memory (STM) deficits are rare, and when they appear, they are often associated with a history of aphasia, raising doubts about the selectivity of these deficits. Recent models of STM consider that STM for item information depends upon activation of the language system, and hence item STM deficits should be associated with language impairment. By contrast, STM for order information is considered to recruit a specific system, distinct from the language system: this system could be impaired in patients with language-independent STM deficits. AIM: We demonstrate here the power of the item-order distinction to separate STM and language impairments in two brain damaged cases with STM impairment and a history of aphasia. METHODS & PROCEDURES: Recognition and recall STM tasks, maximizing STM for either item or order information were administered to patients MB and CG. OUTCOMES & RESULTS: Patient MB showed mild phonological impairment. As predicted, associated STM deficits were characterized by poor item STM but preserved order STM. On the other hand, patient CG showed no residual language deficits. His STM deficit was characterized by poor order STM but perfectly preserved item STM. CONCLUSIONS: This study presents the first double dissociation between item and order STM deficits, and demonstrates the necessity of this distinction for understanding and assessing STM impairment in patients with and without aphasia. [less ▲]Detailed reference viewed: 290 (30 ULg)
An association between short-term memory for order and numerical cognition in 3rd grade kindergarten children.
Attout, Lucie ; Majerus, Steve
Conference (2012, February)
Several studies explored the relationship between verbal short-term memory (STM) and numerical cognition, but with inconclusive findings. The present study re-explored this relationship, by adopting the ... [more ▼]
Several studies explored the relationship between verbal short-term memory (STM) and numerical cognition, but with inconclusive findings. The present study re-explored this relationship, by adopting the critical distinction between STM for item information (the items to be retained) and STM for order information (the order of the items within a list). We hypothesized that especially STM for order should be related to the development of numerical abilities, given that recent studies suggest the intervention of common processes during the representation of order information in STM and numerical tasks. We investigated item and order STM abilities and numerical processing abilities in 72 children during their third year in kindergarten. We observed that order STM abilities, but not item STM abilities, correlated significantly with performance on numerical order judgment and calculation tasks. These associations remained after control of interindividual differences in verbal and non-verbal cognitive efficiency. Our results suggest a specific relationship between order STM processes and numerical cognition, opening new perspectives for our understanding of the STM determinants of numerical cognition development. [less ▲]Detailed reference viewed: 91 (12 ULg)
The impact of visual complexity on visual short-term memory in children with specific language impairment
Leclercq, Anne-Lise ; Maillart, Christelle ; et al
in Journal of the International Neuropsychological Society (2012), 18
Many studies have assessed visual short-term memory (VSTM) abilities in children with specific language impairment (SLI), with contrasting results: some studies observed preserved VSTM capacities while ... [more ▼]
Many studies have assessed visual short-term memory (VSTM) abilities in children with specific language impairment (SLI), with contrasting results: some studies observed preserved VSTM capacities while others reported impaired VSTM. The present study explores the hypothesis that the complexity of the visual information to be encoded and stored might underlie these discrepancies. Four VSTM conditions were administered to a group of 15 children with SLI, as well as to two groups of typically developing children, matched for chronological age and for VSTM capacity for visually simple stimuli, respectively. The stimuli to be remembered varied in their visual similarity and in the number of their visual features. Across the four VSTM conditions, children with SLI showed significantly reduced performance relative to an age-matched control group, and they were more strongly affected by visual similarity and number of features when compared to a control group matched for VSTM capacity for visually simple stimuli. The present results support the hypothesis that stimulus complexity is a determining factor of the poor VSTM performances in children with SLI. [less ▲]Detailed reference viewed: 188 (20 ULg)
Interprétation et évaluation des déficits de la mémoire à court terme verbale dans les troubles spécifiques du développement du langage
in Maillart, Christelle; Schelstraete, Marie-Anne (Eds.) Les dysphasies (2012)Detailed reference viewed: 18 (2 ULg)
Behavioral assessment and diagnosis of disorders of consciousness.
; Majerus, Steve
in Schnakers, C; LAUREYS, Steven (Eds.) Coma and disorders of consiousness (2012)Detailed reference viewed: 6 (0 ULg)
Au-delà de la boucle phonologique : Implications pour l'évaluation de la mémoire à court terme.
Scientific conference (2012)Detailed reference viewed: 27 (4 ULg)
Using the daydreaming frequency scale to investigate the relationships between mind-wandering, psychological well-being, and present-moment awareness
Stawarczyk, David ; Majerus, Steve ; Van der Linden, Martial et al
in Frontiers in Psychology (2012), 3
Recent findings have shown that mind-wandering – the occurrence of stimulusindependent and task-unrelated thoughts – is associated with negative affect and lower psychological well-being. However, it ... [more ▼]
Recent findings have shown that mind-wandering – the occurrence of stimulusindependent and task-unrelated thoughts – is associated with negative affect and lower psychological well-being. However, it remains unclear whether this relationship is due to the occurrence of mind-wandering per se or to the fact that people who mind wander more tend to be generally less attentive to present-moment experience. In three studies, we first validate a French translation of a retrospective self-report questionnaire widely used to assess the general occurrence of mind-wandering in daily life – the Daydreaming Frequency Scale. Using this questionnaire, we then show that the relationship between mind-wandering frequency and psychological distress is fully accounted for by individual differences in dispositional mindful awareness and encoding style.These findings suggest that it may not be mind-wandering per se that is responsible for psychological distress, but rather the general tendency to be less aware and attentive to the present-moment. Thus, although mind-wandering and present-moment awareness are related constructs, they are not reducible to one another, and are distinguishable in terms of their relationship with psychological well-being. [less ▲]Detailed reference viewed: 82 (14 ULg)
Evidence for a specific impairment of serial order short-term memory in dyslexic children
Martinez Perez, Trecy ; Majerus, Steve ; et al
in Dyslexia : The Journal of the British Dyslexia Association (2012), 18(2), 94-109Detailed reference viewed: 351 (29 ULg)
A sensitive scale to assess nociceptive pain in patients with disorders of consciousness.
Chatelle, Camille ; Majerus, Steve ; et al
in Journal of Neurology, Neurosurgery & Psychiatry (2012), 83(12), 1233-7
OBJECTIVE: To determine the sensitivity of the Nociception Coma Scale (NCS), the first scale developed to assess nociceptive pain in vegetative state and minimally conscious state patients, in comparing ... [more ▼]
OBJECTIVE: To determine the sensitivity of the Nociception Coma Scale (NCS), the first scale developed to assess nociceptive pain in vegetative state and minimally conscious state patients, in comparing behavioural changes in response to noxious versus non-noxious stimulation. METHODS: The NCS was administered to assess patients' responses in three conditions: (1) baseline (observation of spontaneous behaviours), (2) non-noxious/tactile stimulation (taps on the patient's shoulder), and (3) noxious stimulation (pressure on the nail bed). RESULTS: We included 64 patients (27 vegetative state and 37 minimally conscious state; age range 20-82 years; 22 traumatic brain injury; 21 in the acute stage). The NCS total scores and subscores (motor, verbal and facial) were higher for the noxious versus the non-noxious stimulation conditions. We did not observe a difference between the non-noxious and the noxious stimulation conditions for the visual subscale. We also found a NCS cut-off value of 4 differentiating the patients receiving a noxious stimulation from patients receiving a non-noxious stimulation. The exclusion of the visual subscale increased the cut-off sensitivity (from 46% to 73%; specificity of 97% and accuracy of 85%). CONCLUSION: We propose a new version of the NCS excluding the visual subscale, the NCS-R, which constitutes a highly sensitive tool to assess responses to nociceptive pain in severely brain injured patients. [less ▲]Detailed reference viewed: 26 (1 ULg)
The Neural Substrates of Memory Suppression: A fMRI Exploration of Directed Forgetting
Bastin, Christine ; Feyers, Dorothée ; Majerus, Steve et al
in PLoS ONE (2012), 7(1), 29905
The directed forgetting paradigm is frequently used to determine the ability to voluntarily suppress information. However, little is known about brain areas associated with information to forget. The ... [more ▼]
The directed forgetting paradigm is frequently used to determine the ability to voluntarily suppress information. However, little is known about brain areas associated with information to forget. The present study used functional magnetic resonance imaging to determine brain activity during the encoding and retrieval phases of an item-method directed forgetting recognition task with neutral verbal material in order to apprehend all processing stages that information to forget and to remember undergoes. We hypothesized that regions supporting few selective processes, namely recollection and familiarity memory processes, working memory, inhibitory and selection processes should be differentially activated during the processing of to-be-remembered and to-be-forgotten items. Successful encoding and retrieval of items to remember engaged the entorhinal cortex, the hippocampus, the anterior medial prefrontal cortex, the left inferior parietal cortex, the posterior cingulate cortex and the precuneus; this set of regions is well known to support deep and associative encoding and retrieval processes in episodic memory. For items to forget, encoding was associated with higher activation in the right middle frontal and posterior parietal cortex, regions known to intervene in attentional control. Items to forget but nevertheless correctly recognized at retrieval yielded activation in the dorsomedial thalamus, associated with familiarity-based memory processes and in the posterior intraparietal sulcus and the anterior cingulate cortex, involved in attentional processes. [less ▲]Detailed reference viewed: 195 (14 ULg)
Functional neuroanatomy underlying the clinical subcategorization of minimally conscious state patients.
Bruno, Marie-Aurélie ; Majerus, Steve ; Boly, Mélanie et al
in Journal of Neurology (2012), 259(6), 1087-98
Patients in a minimally conscious state (MCS) show restricted signs of awareness but are unable to communicate. We assessed cerebral glucose metabolism in MCS patients and tested the hypothesis that this ... [more ▼]
Patients in a minimally conscious state (MCS) show restricted signs of awareness but are unable to communicate. We assessed cerebral glucose metabolism in MCS patients and tested the hypothesis that this entity can be subcategorized into MCS- (i.e., patients only showing nonreflex behavior such as visual pursuit, localization of noxious stimulation and/or contingent behavior) and MCS+ (i.e., patients showing command following).Patterns of cerebral glucose metabolism were studied using [(18)F]-fluorodeoxyglucose-PET in 39 healthy volunteers (aged 46 +/- 18 years) and 27 MCS patients of whom 13 were MCS- (aged 49 +/- 19 years; 4 traumatic; 21 +/- 23 months post injury) and 14 MCS+ (aged 43 +/- 19 years; 5 traumatic; 19 +/- 26 months post injury). Results were thresholded for significance at false discovery rate corrected p < 0.05.We observed a metabolic impairment in a bilateral subcortical (thalamus and caudate) and cortical (fronto-temporo-parietal) network in nontraumatic and traumatic MCS patients. Compared to MCS-, patients in MCS+ showed higher cerebral metabolism in left-sided cortical areas encompassing the language network, premotor, presupplementary motor, and sensorimotor cortices. A functional connectivity study showed that Broca's region was disconnected from the rest of the language network, mesiofrontal and cerebellar areas in MCS- as compared to MCS+ patients.The proposed subcategorization of MCS based on the presence or absence of command following showed a different functional neuroanatomy. MCS- is characterized by preserved right hemispheric cortical metabolism interpreted as evidence of residual sensory consciousness. MCS+ patients showed preserved metabolism and functional connectivity in language networks arguably reflecting some additional higher order or extended consciousness albeit devoid of clinical verbal or nonverbal expression. [less ▲]Detailed reference viewed: 250 (10 ULg)
Attention Supports Verbal Short-Term Memory via Competition between Dorsal and Ventral Attention Networks.
Majerus, Steve ; Attout, Lucie ; D'Argembeau, Arnaud et al
in Cerebral Cortex (2012), 22
Interactions between the neural correlates of short-term memory (STM) and attention have been actively studied in the visual STM domain but much less in the verbal STM domain. Here we show that the same ... [more ▼]
Interactions between the neural correlates of short-term memory (STM) and attention have been actively studied in the visual STM domain but much less in the verbal STM domain. Here we show that the same attention mechanisms that have been shown to shape the neural networks of visual STM also shape those of verbal STM. Based on previous research in visual STM, we contrasted the involvement of a dorsal attention network centered on the intraparietal sulcus supporting task-related attention and a ventral attention network centered on the temporoparietal junction supporting stimulus-related attention. We observed that, with increasing STM load, the dorsal attention network was activated while the ventral attention network was deactivated, especially during early maintenance. Importantly, activation in the ventral attention network increased in response to task-irrelevant stimuli briefly presented during the maintenance phase of the STM trials but only during low-load STM conditions, which were associated with the lowest levels of activity in the dorsal attention network during encoding and early maintenance. By demonstrating a trade-off between task-related and stimulus-related attention networks during verbal STM, this study highlights the dynamics of attentional processes involved in verbal STM. [less ▲]Detailed reference viewed: 183 (35 ULg)
Two distinct origins of long-term learning effects in verbal short-term memory
Majerus, Steve ; Martinez Perez, Trecy ;
in Journal of Memory & Language (2012), 66
Verbal short-term memory (STM) is highly sensitive to learning effects: digit sequences or nonword sequences which have been rendered more familiar via repeated exposure are recalled more accurately. In ... [more ▼]
Verbal short-term memory (STM) is highly sensitive to learning effects: digit sequences or nonword sequences which have been rendered more familiar via repeated exposure are recalled more accurately. In this study we show that sublist-level, incidental learning of item co-occurrence regularities affects immediate serial recall of words and nonwords, but not digits. In contrast, list-level chunk learning affects serial recall of digits. In a first series of experiments, participants heard a continuous sequence of digits in which the co-occurrence of digits was governed by an artificial grammar. In a subsequent STM test participants recalled lists that were legal or illegal according to the rules of the artificial grammar. No advantage for legal lists over illegal lists was observed. A second series of experiments used the same incidental learning procedure with nonwords or non-digit words. An advantage for legal versus illegal list recall was observed. A final experiment used an incidental learning task repeating whole lists of digits; this led to a substantial recall advantage for legal versus illegal digit lists. These data show that serial recall of non-digit words is supported by sublist-level probabilistic knowledge, whereas serial recall of digits is only supported by incidental learning of whole lists. [less ▲]Detailed reference viewed: 309 (26 ULg)