References of "Majerus, Steve"
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See detailThe Neural Substrates of Memory Suppression: A fMRI Exploration of Directed Forgetting
Bastin, Christine ULg; Feyers, Dorothée ULg; Majerus, Steve ULg 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 ▲]

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See detailFunctional neuroanatomy underlying the clinical subcategorization of minimally conscious state patients.
Bruno, Marie-Aurélie ULg; Majerus, Steve ULg; Boly, Mélanie ULg 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 ▲]

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See detailAttention Supports Verbal Short-Term Memory via Competition between Dorsal and Ventral Attention Networks.
Majerus, Steve ULg; Attout, Lucie ULg; D'Argembeau, Arnaud ULg 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 ▲]

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See detailTwo distinct origins of long-term learning effects in verbal short-term memory
Majerus, Steve ULg; Martinez Perez, Trecy ULg; Oberauer, Klaus

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 ▲]

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See detailThe impact of visual complexity on visual short-term memory in children with specific language impairment
Leclercq, Anne-Lise ULg; Maillart, Christelle ULg; Pauquay, Sarah 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 ▲]

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See detailThe contribution of short-term memory for serial order to early reading acquisition: Evidence from a longitudinal study
Martinez Perez, Trecy ULg; Majerus, Steve ULg; Poncelet, Martine ULg

in Journal of Experimental Child Psychology (2012), 111

Early reading acquisition skills have been linked to verbal short-term memory (STM) capacity. However, the nature of this relationship remains controversial, since verbal STM, like reading acquisition ... [more ▼]

Early reading acquisition skills have been linked to verbal short-term memory (STM) capacity. However, the nature of this relationship remains controversial, since verbal STM, like reading acquisition, depends upon the complexity of underlying phonological processing skills. This longitudinal study addressed the relation between STM and reading decoding acquisition by distinguishing between STM for item and STM for order information, based on recent studies showing that STM for item information recruits underlying phonological representations, but not STM for order information. If there is a specific link between STM and reading decoding acquisition, STM for order information should be an independent predictor of reading decoding acquisition. Tasks maximizing STM for serial order or item information, measures of phonological abilities and reading tests were administered to children followed from kindergarten through 1st grade. We observed that order STM capacity but not item STM capacity predicted independent variance in reading decoding abilities one year later. These results highlight the specific role of STM for order in reading decoding acquisition, and argue for a causal role of order STM capacity in reading acquisition. Mechanisms relating STM for order information and reading acquisition will be discussed. [less ▲]

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See detailThe importance of distinguishing item and order memory for understanding short-term memory deficits in brain-damaged patients
Attout, Lucie ULg; VAN DER KAA, Marie-Anne ULg; GEORGE, Mercédès ULg et al

Poster (2011, October 18)

Selective verbal short-term memory (STM) deficits are rare and are often associated with a history of aphasia, raising doubts about the selectivity of these deficits. We explore here the distinction ... [more ▼]

Selective verbal short-term memory (STM) deficits are rare and are often associated with a history of aphasia, raising doubts about the selectivity of these deficits. We explore here the distinction between STM for item information (the items and their phonological and semantic characteristics) and STM for order information (the order of items within a list) to separate STM and language impairment. 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. Hence, order STM should be impaired in patients with language-independent STM deficits. We applied this rationale to the exploration of STM profiles of two patients with a history of aphasia, MB and CG. At the time of this study, patient MB showed poor digit and word STM spans associated with a mild impairment at the level of phonological input processing. Patient CG showed poor STM spans with no residual language impairment. A first experiment assessed STM for order and item information, using order and item probe recognition tasks. Patient MB showed severely impaired performance in the item condition (Z=-4.71; p<.001) but a milder deficit in the order condition (Z=-2.17; p<.05). CG on the other hand showed perfectly preserved performance for the item condition (Z=-0.43) but significantly slowed response times for the order condition (Z=-2.20; p<.05). In a second experiment determining item and order error proportions in an immediate serial recall task for six-word lists, MB showed a significantly increased proportion of item errors (Z=-3.24 and -2.6 for positions 5 and 6, respectively; p<.05) but not of order errors (Z=-1.47), while CG showed perfectly preserved item recall (Z=0.22) but an increase of order errors especially in final list positions (Z =-2.57 for position 6; p<.05). A third experiment assessed reconstruction of serial order for digit lists showing perfectly preserved performance in patient MB (Z=1.32) but severely impaired performance in patient CG (Z=-3.49; p<.05). A final experiment assessed new word learning performance, given that STM for order has been shown to be a critical determinant of vocabulary acquisition in children and adults. CG showed impaired new word learning performance in a paired associate word-new word learning experiment (Z=-3.29; p<.05) but not in a word-word learning control experiment (Z=0.13), while MB showed a more general verbal learning impairment (word-nonword: Z=-3.09, p<.05; word-word: Z=-4.8, p<.05). This study provides the first demonstration of a dissociation between STM for order and STM for item information in patients with a history of aphasia, and further shows that patients with residual language impairment are more likely to present impaired STM for item information which is considered to depend on the integrity of the language system. Order STM deficits on the other hand may represent what is commonly referred to as selective STM impairment, highlighting the importance of distinguishing between item and order STM processes when exploring STM deficits in aphasic patients. [less ▲]

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See detailIncidental non linguistic regularities learning in Children with
Gabriel, Audrey ULg; Meulemans, Thierry ULg; Parisse, Christophe et al

Poster (2011, July)

Recent studies on specific language impairment (SLI) have suggested that language deficits could be partly explained by the Procedural Deficit hypothesis (PDH; Ullman & Pierpont, 2005). Tomblin et al ... [more ▼]

Recent studies on specific language impairment (SLI) have suggested that language deficits could be partly explained by the Procedural Deficit hypothesis (PDH; Ullman & Pierpont, 2005). Tomblin et al. (2007) and Lum et al. (2009; 2011) obtained data supporting this interpretation with the serial reaction time (SRT) task, as well as Evans et al. (2009) and Plante et al. (2002) with artificial grammar tasks. Recently, Gabriel et al. (2011) obtained contrasting results, showing that children with SLI were able to detect non linguistic regularities during a SRT task. The aim of this study was to assess the PDH by using a non-linguistic artificial grammar learning tasks in order to mimic real conditions of language acquisition. Twenty-three children with SLI and their typically developing (TD) peers are compared on a task in which the incidental learning sequence was presented through visual shapes via a laptop.These results confirm our previous study (Gabriel et al., 2011) by showing that children with SLI detect the rules in non-linguistic conditions. • So, contrary to results of previous studies (Evans et al., 2009; Lum et al., 2009; 2011; Plante et al., 2002; Tomblin et al., 2007), this study does not confirm the PDH in children with SLI, or at least suggests that, if present, the deficit of the procedural system in SLI is not going beyond the language system. [less ▲]

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See detailSpecific contribution of short-term memory for serial order information to early reading acquisition: A longitudinal study
Martinez Perez, Trecy ULg; Majerus, Steve ULg; Poncelet, Martine ULg

Poster (2011, June 02)

Early reading acquisition skills have been linked to verbal short-term memory (STM) capacity. However, the nature of this relationship remains controversial. Here we distinguished between STM for item and ... [more ▼]

Early reading acquisition skills have been linked to verbal short-term memory (STM) capacity. However, the nature of this relationship remains controversial. Here we distinguished between STM for item and order information based on recent studies showing that STM for order is an important and independent predictor of oral language development. Tasks maximizing STM for serial-order or item information and reading tests were administered to 42 children from kindergarten through 1st grade. Results showed that order STM capacity measured at kindergarten predicted phonological recoding abilities at 1st grade. Implications of poor serial-order STM for reading acquisition in dyslexia are discussed. [less ▲]

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See detailThe importance of short-term memory for order in dissociating short-term memory and language deficits
Attout, Lucie ULg; VAN DER KAA, Marie-Anne ULg; GEORGE, Mercédès ULg et al

Poster (2011, May 27)

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. We explore ... [more ▼]

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. We explore here the distinction between STM for item information and STM for order information to separate STM and language impairments. 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. In this view, order STM should be impaired in patients with STM deficits that cannot be accounted for by language impairment. We applied this rationale to the exploration of STM profiles of patients MB and CG. Patient MB showed mild phonological impairment and associated STM deficits. As predicted, these were characterized by poor item STM but preserved order STM. Patient CG showed verbal STM deficits with no associated language deficits. His STM deficit was characterized by poor order STM but relatively preserved item STM. This study presents the first double dissociation between item and order STM deficits, demonstrating the necessity of this distinction for understanding selective STM impairment. [less ▲]

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See detailPhenomenology, function, and neural correlates of mind-wandering
Stawarczyk, David ULg; Majerus, Steve ULg; D'Argembeau, Arnaud ULg

Conference (2011, May 27)

Mind-wandering refers to the occurrence of thoughts whose content is both decoupled from stimuli present in the immediate environment and unrelated to the task currently being carried out. In a series of ... [more ▼]

Mind-wandering refers to the occurrence of thoughts whose content is both decoupled from stimuli present in the immediate environment and unrelated to the task currently being carried out. In a series of experiments, we used a newly designed experience sampling method to assess mind-wandering episodes and to distinguish them from other kinds of distractions (irrelevant interoceptive/exteroceptive sensory perceptions and interfering thoughts related to the appraisal of the current task). In Experiment 1, we examined the impact of mind-wandering on performance of the Sustained Attention to Response Task (SART; a Go/No-Go task). Analyses demonstrated that episodes of mind-wandering impair SART performance to the same extent as irrelevant sensory perceptions. In Experiment 2, we focused on the content of mind-wandering in order to assess its possible functions. We observed that most of reported mind-wandering episodes refer to the anticipation and planning of future events. Furthermore, this “prospective bias” was increased when participants’ attention had been oriented toward their personal goals prior to performing the SART. In Experiment 3, we examined the neural correlates of mind-wandering using functional magnetic resonance imaging. The results showed that the brain regions that were more active during episodes of mind-wandering are similar to the regions that have been associated with imagining future events in previous studies. Together, these results suggest that although episodes of mind-wandering negatively impact current task performance, they may have important adaptive value and could, in particular, play a key role in planning for the future. [less ▲]

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See detailEarly contribution of phonological awareness and later influence of phonological memory throughout reading acquisition
Nithart, C.; Demont, E.; Majerus, Steve ULg et al

in Journal of Research in Reading (2011), 34

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See detailSKOOL versus ZOOL: Effects of orthographic and phonological long term memory on nonword immediate serial recall
Tree, Jeremy; Longmore, Chris; Majerus, Steve ULg

in Memory (2011), 19

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See detailLecture et habiletés phonologiques associées chez l’adulte dyslexique
Martinez Perez, Trecy ULg; Majerus, Steve ULg; Poncelet, Martine ULg

in Lederlé, E (Ed.) Les troubles du langage écrits : Regards croisés (2011)

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See detailEvidence for atypical categorical speech perception in Williams syndrome.
Majerus, Steve ULg; Poncelet, Martine ULg; Bérault, Aurélie et al

in Journal of Neurolinguistics (2011), 24

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See detailNeural Correlates of Ongoing Conscious Experience: Both Task-Unrelatedness and Stimulus-Independence Are Related to Default Network Activity
Stawarczyk, David ULg; Majerus, Steve ULg; Maquet, Pierre ULg et al

in PLoS ONE (2011), 6(2), 16997

The default mode network (DMN) is a set of brain regions that consistently shows higher activity at rest compared to tasks requiring sustained focused attention toward externally presented stimuli. The ... [more ▼]

The default mode network (DMN) is a set of brain regions that consistently shows higher activity at rest compared to tasks requiring sustained focused attention toward externally presented stimuli. The cognitive processes that the DMN possibly underlies remain a matter of debate. It has alternately been proposed that DMN activity reflects unfocused attention toward external stimuli or the occurrence of internally generated thoughts. The present study aimed at clarifying this issue by investigating the neural correlates of the various kinds of conscious experiences that can occur during task performance. Four classes of conscious experiences (i.e., being fully focused on the task, distractions by irrelevant sensations/perceptions, interfering thoughts related to the appraisal of the task, and mind-wandering) that varied along two dimensions (“task-relatedness” and “stimulus-dependency”) were sampled using thought-probes while the participants performed a go/no-go task. Analyses performed on the intervals preceding each probe according to the reported subjective experience revealed that both dimensions are relevant to explain activity in several regions of the DMN, namely the medial prefrontal cortex, posterior cingulate cortex/precuneus, and posterior inferior parietal lobe. Notably, an additive effect of the two dimensions was demonstrated for midline DMN regions. On the other hand, lateral temporal regions (also part of the DMN) were specifically related to stimulus-independent reports. These results suggest that midline DMN regions underlie cognitive processes that are active during both internal thoughts and external unfocused attention. They also strengthen the view that the DMN can be fractionated into different subcomponents and reveal the necessity to consider both the stimulus-dependent and the task-related dimensions of conscious experiences when studying the possible functional roles of the DMN. [less ▲]

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See detailMind-wandering: Phenomenology and function as assessed with a novel experience sampling method
Stawarczyk, David ULg; Majerus, Steve ULg; Maj, Michalina et al

in Acta Psychologica (2011), 136(3), 370-381

Mind-wandering refers to the occurrence of thoughts whose content is both decoupled from stimuli present in the current environment and unrelated to the task being carried out at the moment of their ... [more ▼]

Mind-wandering refers to the occurrence of thoughts whose content is both decoupled from stimuli present in the current environment and unrelated to the task being carried out at the moment of their occurrence. The core of this phenomenon is therefore stimulus-independent and task-unrelated thoughts (SITUTs). In the present study, we designed a novel experience sampling method which permitted to isolate SITUTs from other kinds of distractions (i.e., irrelevant interoceptive/exteroceptive sensory perceptions and interfering thoughts related to the appraisal of the current task). In Experiment 1, we examined the impact of SITUTs on the performance of the Sustained Attention to Response Task (SART; a Go/No-Go task). Analyses demonstrated that SITUTs impair SART performance to the same extent as irrelevant sensory perceptions. In Experiment 2, we further examined SITUTs in order to assess the possible functions of mind-wandering. We observed that the content of most of reported SITUTs refers to the anticipation and planning of future events. Furthermore, this “prospective bias” was increased when participants’ attention had been oriented toward their personal goals before performing the SART. These data support the view that an important function of mind-wandering relates to the anticipation and planning of the future. [less ▲]

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See detailImpaired verbal short-term memory for serial order information in dyslexic adults
Martinez Perez, Trecy ULg; Majerus, Steve ULg; Poncelet, Martine ULg

Poster (2010, September 10)

This study used the distinction of item and order information in verbal short-term memory (STM) to further our understanding of verbal STM impairments in dyslexia. Item STM has been shown to depend on the ... [more ▼]

This study used the distinction of item and order information in verbal short-term memory (STM) to further our understanding of verbal STM impairments in dyslexia. Item STM has been shown to depend on the quality of underlying phonological representations and hence should be impaired in dyslexic participants given their poor phonological processing abilities. On the other hand, order STM represents a specific STM capacity predicting learning capacity for new phonological and orthographic sequences (Majerus et al., 2006; Nithart et al, 2010). If STM impairments contribute to dyslexia, then especially order STM should be impaired, in addition to item STM. [less ▲]

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See detailSpoken sentence comprehension in children with developmental dyslexia
Leclercq, Anne-Lise ULg; Majerus, Steve ULg; Guasti, Maria Teresa et al

Poster (2010, September 09)

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