Working memory deficits in developmental dyscalculia: the importance of serial order.
Attout, Lucie ; Majerus, Steve
in Child Neuropsychology : A Journal on Normal & Abnormal Development in Childhood & Adolescence (in press)Detailed reference viewed: 60 (10 ULg)
Impact of Aphasia on Consciousness Assessment: A Cross-Sectional Study.
; ; et al
in Neurorehabilitation & Neural Repair (2015), 29
BACKGROUND: . Previous findings suggest that language disorders may occur in severely brain-injured patients and could interfere with behavioral assessments of consciousness. However, no study ... [more ▼]
BACKGROUND: . Previous findings suggest that language disorders may occur in severely brain-injured patients and could interfere with behavioral assessments of consciousness. However, no study investigated to what extent language impairment could affect patients' behavioral responses. OBJECTIVE: . To estimate the impact of receptive and/or productive language impairments on consciousness assessment. METHODS: . Twenty-four acute and subacute stroke patients with different types of aphasia (global, n = 11; Broca, n = 4; Wernicke, n = 3; anomic, n = 4; mixed, n = 2) were recruited in neurology and neurosurgery units as well as in rehabilitation centers. The Coma Recovery Scale-Revised (CRS-R) was administered. RESULTS: . We observed that 25% (6 out of 24) of stroke patients with a diagnosis of aphasia and 54% (6 out of 11) of patients with a diagnosis of global aphasia did not reach the maximal CRS-R total score of 23. An underestimation of the consciousness level was observed in 3 patients with global aphasia who could have been misdiagnosed as being in a minimally conscious state, even in the absence of any documented period of coma. More precisely, lower subscores were observed on the communication, motor, oromotor, and arousal subscales. CONCLUSION: . Consciousness assessment may be complicated by the co-occurrence of severe language deficits. This stresses the importance of developing new tools or identifying items in existing scales, which may allow the detection of language impairment in severely brain-injured patients. [less ▲]Detailed reference viewed: 27 (3 ULg)
The Impact of Attentional Allocation Capacities on Nonword Repetition in Children with Specific Language Impairment
Leclercq, Anne-Lise ; Maillart, Christelle ; et al
in Clinical Linguistics & Phonetics (2015)
This study aimed at directly assessing the hypothesis that attentional allocation capacity influences poor NWR performances in children with SLI, using an attention demanding visual search task given ... [more ▼]
This study aimed at directly assessing the hypothesis that attentional allocation capacity influences poor NWR performances in children with SLI, using an attention demanding visual search task given concurrently with the NWR task. Twenty-one children with SLI, 21 typically-developing children matched on age, and 21 typically-developing children matched on nonword span performed an immediate serial recall task of nonwords. The nonword lists were presented either alone or concurrently with the visual search task. Overall, results revealed a resource-sharing trade-off between the two tasks. Children with SLI were affected to the same extent as their span-matched controls by the necessity to allocate their attentional resources between the two tasks. Interestingly, nonword processing strategies seemed to differ among groups: age-matched controls allocated a larger part of their attentional resources to the encoding stage, while nonword recall was more attention demanding in children with SLI and younger controls. [less ▲]Detailed reference viewed: 32 (4 ULg)
The neural basis of temporal order processing in past and future thought
D'Argembeau, Arnaud ; Jeunehomme, Olivier ; Majerus, Steve et al
in Journal of Cognitive Neuroscience (2015), 27Detailed reference viewed: 80 (20 ULg)
The emergence of verbal short-term memory from language, serial order and attentional processing.
Conference (2014, December 11)Detailed reference viewed: 29 (8 ULg)
Effets du vieillissement sur les réseaux cérébraux attentionnels liés à la tâche et au stimulus durant une épreuve de mémoire à court terme
Kurth, Sophie ; Majerus, Steve ; Bastin, Christine et al
Poster (2014, December 05)Detailed reference viewed: 45 (10 ULg)
Cognitive rehabilitation : Past, present and future.
Conference (2014, October 04)Detailed reference viewed: 16 (4 ULg)
Visual and verbal materials to be remembered produce a common neural pattern : Evidence for attention- based of working memory.
Majerus, Steve ;
Conference (2014, September 02)Detailed reference viewed: 17 (4 ULg)
Cross-Modal Decoding of Neural Patterns Associated with Working Memory: Evidence for Attention-Based Accounts of Working Memory
Majerus, Steve ; ; Peters, Frédéric et al
in Cerebral Cortex (2014)
Recent studies suggest common neural substrates involved in verbal and visual working memory (WM), interpreted as reflecting shared attention-based, short-term retention mechanisms. We used a machine ... [more ▼]
Recent studies suggest common neural substrates involved in verbal and visual working memory (WM), interpreted as reflecting shared attention-based, short-term retention mechanisms. We used a machine-learning approach to determine more directly the extent to which common neural patterns characterize retention in verbal WM and visual WM. Verbal WM was assessed via a standard delayed probe recognition task for letter sequences of variable length. Visual WM was assessed via a visual array WM task involving the maintenance of variable amounts of visual information in the focus of attention. We trained a classifier to distinguish neural activation patterns associated with high- and low-visual WM load and tested the ability of this classifier to predict verbal WM load (high–low) from their associated neural activation patterns, and vice versa. We observed significant between-task prediction of load effects during WM maintenance, in posterior parietal and superior frontal regions of the dorsal attention network; in contrast, between-task prediction in sensory processing cortices was restricted to the encoding stage. Furthermore, between-task prediction of load effects was strongest in those participants presenting the highest capacity for the visual WM task. This study provides novel evidence for common, attention-based neural patterns supporting verbal and visual WM. [less ▲]Detailed reference viewed: 58 (12 ULg)
Working memory for serial order and the development of verbal and numerical abilities.
Conference (2014, July 09)Detailed reference viewed: 15 (2 ULg)
Volitional electromyographic responses in disorders of consciousness
; Gosseries, Olivia ; Noirhomme, Quentin et al
in Brain Injury (2014)
The aim of the study was to validate the use of electromyography (EMG) for detecting responses to command in patients in vegetative state/unresponsive wakefulness syndrome (VS/UWS) or in minimally ... [more ▼]
The aim of the study was to validate the use of electromyography (EMG) for detecting responses to command in patients in vegetative state/unresponsive wakefulness syndrome (VS/UWS) or in minimally conscious state (MCS). Methods: Thirty-eight patients were included in the study (23 traumatic, 25 patients >1 year post-onset), 10 diagnosed as being in VS/UWS, eight in MCS- (no response to command) and 20 in MCS+ (response to command). Eighteen age-matched controls participated in the experiment. The paradigm consisted of three commands (i.e. 'Move your hands', 'Move your legs' and 'Clench your teeth') and one control sentence (i.e. 'It is a sunny day') presented in random order. Each auditory stimulus was repeated 4-times within one block with a stimulus-onset asynchrony of 30 seconds. Results: Post-hoc analyses with Bonferroni correction revealed that EMG activity was higher solely for the target command in one patient in permanent VS/UWS and in three patients in MCS+. Conclusion: The use of EMG could help clinicians to detect conscious patients who do not show any volitional response during standard behavioural assessments. However, further investigations should determine the sensitivity of EMG as compared to neuroimaging and electrophysiological assessments. [less ▲]Detailed reference viewed: 22 (4 ULg)
The Impact of Dual-Tasking on Verbal Short-Term Memory in Children with Specific Language Impairment
Leclercq, Anne-Lise ; Maillart, Christelle ; et al
Poster (2014, June)
Limitations in general processing capacities have been proposed to account for poor verbal short-term memory (STM) performances in children with SLI. Previous studies observed that STM performances ... [more ▼]
Limitations in general processing capacities have been proposed to account for poor verbal short-term memory (STM) performances in children with SLI. Previous studies observed that STM performances decreased to a larger extent in children with SLI as compared to their unaffected peers when the processing demands of the task increased (e.g., Ellis Weismer, et al., 2005; Montgomery, 2000a,b). However, in these studies, the increase in attention processing demands went with an increase in linguistic processing demands. Since children with SLI experience language processing problems, it is not clear whether general attention problems or language processing problems are at the root of their larger performance decrease as compared to their unaffected peers. This study aims at directly assessing the hypothesis that limitations in general attentional capacity are at the root of poor STM performances in children with SLI, using an attention demanding visual search task administered concurrently with nonword repetition task. Twenty-three children with SLI, 23 age-matched children, and 23 nonword span-matched children performed immediate serial recall tasks of nonwords. The STM lists were presented either alone or concurrently with the target detection task. Moreover, the target detection task either stopped or continued when children had to recall the nonwords. Results show a main effect of dual task condition on both nonword repetition accuracy and target detection accuracy. Performances in children with SLI were not more affected than in controls by the necessity to perform a concurrent visual attention task during nonword lists presentation. However, nonword recall seemed to be more challenging for children with SLI than for age-matched controls. Indeed, performances in the visual task were lower in children with SLI than in their age-matched controls, but not as compared to nonword span-matched controls. [less ▲]Detailed reference viewed: 72 (9 ULg)
Domain generality of serial order processing in short-term memory : Evidence from musical and verbal domains.
Majerus, Steve ; Gorin, Simon
Conference (2014, May 27)
Recent models of verbal short-term memory (STM) propose a distinction between item storage processes, which are viewed as domain-specific, and order storage processes, which are considered by some authors ... [more ▼]
Recent models of verbal short-term memory (STM) propose a distinction between item storage processes, which are viewed as domain-specific, and order storage processes, which are considered by some authors to be domain-general, at least as regards verbal and visual STM domains. Here we provide further evidence for domain-specific item STM processes and domain-general order STM processes by comparing item and order processing in verbal and musical STM domains. The musical domain is particularly relevant here given its reliance on different kinds of sequential processes (e.g., tones successions, rhythm). Using an interindividual differences approach, we administered to a group of young healthy adults different tasks requiring retention of item identity for words or tones, and tasks requiring retention of serial order information for word sequences or note sequences, as well as a task measuring retention abilities for rhythmic information. For the item STM tasks, we observed strong intercorrelations for within-domain WM measures, but not between-domain WM measures, after controlling for general WM abilities. For the serial order STM tasks, we observed a specific association with the rhythm STM task. These results highlight the importance of temporal sequential processes, as measured by the rhythm STM task, as a driving factor of domain-general STM processes in verbal and musical domains. They furthermore confirm the domain-specificity of item STM processes. [less ▲]Detailed reference viewed: 100 (28 ULg)
The heterogeneity of working memory impairment in neurodevelopmental disorders : Evidence from three neurogenetic disorders.
Conference (2014, April 18)Detailed reference viewed: 13 (1 ULg)
Relationships between mind-wandering and attentional control abilities in young adults and adolescents
Stawarczyk, David ; Majerus, Steve ; Catale, Corinne et al
in Acta Psychologica (2014), 148
Recent findings suggest that mind-wandering—the occurrence of thoughts that are both stimulus-independent and task-unrelated—corresponds to temporary failures in attentional control processes involved in ... [more ▼]
Recent findings suggest that mind-wandering—the occurrence of thoughts that are both stimulus-independent and task-unrelated—corresponds to temporary failures in attentional control processes involved in maintaining constant task-focused attention. Studies supporting this proposal are, however, limited by a possible confound between mind-wandering episodes and other kinds of conscious experiences, such as external distractions (i.e., interoceptive sensations and exteroceptive perceptions). In the present study, we addressed this issue by examining, in adolescents and young adults, the relations between tasks measuring attentional control abilities and a measure of mind-wandering that is distinct from external distractions. We observed (1) that adolescents experienced more frequent external distractions, but not more mind-wandering, than young adults during the Sustained Attention to Response Task (SART) and (2) that, in young adults, the influence of external distractions on SART performance was fully accounted for by attentional control abilities, whereas mind-wandering was associated with decreases in SART performance above and beyond what was explained by attentional control abilities. These results show that mind-wandering cannot be entirely reduced to failures in the ability to maintain one’s attention focused on task, and suggest that external distractions rather than mind-wandering are due to attentional control failures. [less ▲]Detailed reference viewed: 44 (10 ULg)
The impact of lexical frequency on sentence comprehension in children with specific language impairment
Leclercq, Anne-Lise ; Majerus, Steve ; et al
in Research in Developmental Disabilities (2014), 35
Children with SLI generally exhibit poor sentence comprehension skills. We examined the specific impact of grammatical complexity and lexical frequency on comprehension performance, yielding contrasting ... [more ▼]
Children with SLI generally exhibit poor sentence comprehension skills. We examined the specific impact of grammatical complexity and lexical frequency on comprehension performance, yielding contrasting results. The present study sheds new light on sentence comprehension in children with SLI by investigating a linguistic factor which has attracted little research interest: the impact of the lexical frequency of known words on sentence comprehension. We also examined the impact of grammatical complexity and sentence length by independently varying these two factors. Fifteen children with SLI, 15 age- and IQ-matched controls, and 15 controls matched on lexical and grammatical skills, performed sentence comprehension tasks in which three linguistic factors were manipulated: lexical frequency (sentences containing words of either low or high lexical frequency), grammatical complexity (sentence containing either a subject relative clause or an object relative clause) and sentence length (either short or long sentences). Results indicated that children with SLI performed more poorly overall compared to age- and IQmatched children and to lexical and morphosyntactic age-matched children. However, their performance was not more affected by either sentence length or clause type than that of control children. Only lexical frequency affected sentence comprehension to a greater extent in children with SLI relative to the control groups, revealing that SLI children’s sentence comprehension abilities are particularly affected by the presence of lowfrequency but familiar words. [less ▲]Detailed reference viewed: 62 (16 ULg)
Preserved Covert Cognition in Noncommunicative Patients With Severe Brain Injury?
; ; et al
in Neurorehabilitation and Neural Repair (2014)Detailed reference viewed: 25 (10 ULg)
Memoire de travail verbale ou Comment s'en sortir des méandres théoriques.
Conference (2014)Detailed reference viewed: 33 (4 ULg)