Social cognition in adult survivors of brain tumors: studying the relationship between theory of mind and quality of life.

OBJECTIVE: The present study is the first to examine theory of mind (ToM) sequelae in a sample of adult survivors of primary brain tumors, and to investigate the assumed relationship between ToM and health-related quality of life (HRQoL). METHOD: Participants were 40 long-term adult survivors of primary brain tumors and 40 matched healthy controls. They completed ToM tests (Faux-Pas test and Advanced ToM task) and two questionnaires assessing HRQoL (36-Item Short-Form Health Survey and EORTC QLQ-C30/QLQ-BN20). Their relatives also completed an observer-rated version of the SF-36 questionnaire. RESULTS: Survivors performed worse than controls only on the Advanced ToM task. Overall, patients and caregivers reported more problems than healthy controls and their relatives regarding both global HRQoL and its social/emotional aspects. No relationship was found between ToM and HRQoL scores. CONCLUSION: Adult survivors of primary brain tumors may exhibit ToM deficits several years after treatment and report more problems on social/emotional HRQoL components. Our findings highlight the need to consider these late effects in survivors' long-term follow-up, even if the clinical involvement of ToM deficits still needs to be elucidated. The assessment of ToM deficits and their potential impact on survivors' everyday life is thoroughly discussed.

Knowing "what for," but not "where": Dissociation between functional and contextual tool knowledge in healthy individuals and patients with dementia.

OBJECTIVE: Semantic tool knowledge underlies the ability to perform activities of daily living. Models of apraxia have emphasized the role of functional knowledge about the action performed with tools (e.g., a hammer and a mallet allow a "hammering" action), and contextual knowledge informing individuals about where to find tools in the social space (e.g., a hammer and a mallet can be found in a workshop). The goal of this study was to test whether contextual or functional knowledge, would be central in the organization of tool knowledge. It was assumed that contextual knowledge would be more salient than functional knowledge for healthy controls and that patients with dementia would show impaired contextual knowledge. METHODS: We created an original, open-ended categorization task with ambiguity, in which the same familiar tools could be matched on either contextual or functional criteria. RESULTS: In our findings, healthy controls prioritized a contextual, over a functional criterion. Patients with dementia had normal visual categorization skills (as demonstrated by an original picture categorization task), yet they made less contextual, but more functional associations than healthy controls. CONCLUSION: The findings support a dissociation between functional knowledge ("what for") on the one hand, and contextual knowledge ("where") on the other hand. While functional knowledge may be distributed across semantic and action-related factors, contextual knowledge may actually be the name of higher-order social norms applied to tool knowledge. These findings may encourage researchers to test both functional and contextual knowledge to diagnose semantic deficits and to use open-ended categorization tests.

Pragmatic language comprehension: Role of theory of mind, executive functions, and the prefrontal cortex.

The specific contribution of focal damage of the prefrontal cortex and the cognitive mechanisms accounting for communicative-pragmatic disorders remains unclear. The objective of the current study was to investigate the impact of focal prefrontal cortex damage on the ability to understand indirect speech or hints and to identify the prefrontal neural mechanisms involved. We also examined the underlying cognitive mechanisms of disorders of indirect speech understanding particularly theory of mind and executive functions. Thirty patients with focal prefrontal cortex damage and 30 control subjects were compared on their performances on the Hinting task assessing pragmatic language skills, the "Faux-Pas" task and the Reading the Mind in the Eyes task assessing Theory of Mind and a battery of executive tasks. Patients were significantly impaired compared with control subjects on all these abilities. Both deficits of executive functions and theory of mind were able to predict impaired ability of patients in understanding non-literal meanings on the Hinting task. Finally, using voxel-based lesion analysis we identified a partially shared neural prefrontal network involved in all these abilities centered on the dorsomedial and ventral regions of the prefrontal cortex.

Comprehensive assessment of executive functioning following childhood severe traumatic brain injury: clinical utility of the child executive functions battery.

Objectives: To perform a detailed description of executive functioning following moderate-to-severe childhood traumatic brain injury (TBI), and to study demographic and severity factors influencing outcome. Methods: A convenience sample of children/adolescents aged 7-16 years, referred to a rehabilitation department after a TBI (n = 43), was compared to normative data using a newly developed neuropsychological test battery (Child Executive Functions Battery-CEF-B) and the BRIEF. Results: Performance in the TBI group was significantly impaired in most of the CEF-B subtests, with moderate to large effect sizes. Regarding everyday life, patients were significantly impaired in most BRIEF clinical scales, either in parent or in teacher reports. Univariate correlations in the TBI group did not yield significant correlations between the CEF-B and socio-economic status, TBI severity, age at injury, or time since injury. Conclusion: Executive functioning is severely altered following moderate-to-severe childhood TBI and is best assessed using a combination of developmentally appropriate neuropsychological tests and behavioral ratings to provide a comprehensive understanding of children's executive functions.

Role of the prefrontal cortex and executive functions in basic emotions recognition: evidence from patients with focal damage to the prefrontal cortex.

Few studies have examined the specific contribution of focal damage of the prefrontal cortex and executive dysfunction to emotion recognition deficits, with results reporting controversial findings. This study investigated the performance of 30 patients with prefrontal cortex damage and 30 matched controls on a battery of executive measures assessing processes of inhibition, flexibility, and planning and a task of emotion recognition with also a particular attention to the examination of the association between these domains. The results showed that compared with control participants, patients with prefrontal cortex damage were impaired in recognizing the three negative emotions of fear, sadness, and anger and were also impaired on all executive measures. Moreover, by examining the association between both these domains, using correlation and regression analyses, we noted that impaired performance in recognizing emotions of fear, sadness, and anger was predicted by impaired performances on the measures of inhibition and flexibility or "set-shifting" suggesting that the ability to recognize emotions could be at least to some extent cognitively mediated. Finally, using a voxel-based lesion technique, we identified a partially common prefrontal network underlying deficits on executive functions and emotions recognition centered on the ventral and medial parts of the prefrontal cortex, reflecting beyond the neural network involved in recognizing negative emotions per se that of the cognitive processes elicited by this emotion task.

Sensory Integration Deficits in Neurodegenerative Diseases: Implications for Apraxia.

OBJECTIVE: Apraxia is the inability to perform voluntary, skilled movements following brain lesions, in the absence of sensory integration deficits. Yet, patients with neurodegenerative diseases (ND) may have sensory integration deficits, so we tested the associations and dissociations between apraxia and sensory integration. METHODS: A total of 44 patients with ND and 20 healthy controls underwent extensive testing of sensory integration (i.e., localization of tactile, visual, and proprioceptive stimuli; agraphesthesia; astereognosis) and apraxia (i.e., finger dexterity, imitation, tool use). RESULTS: The results showed (i) that patients with Alzheimer's disease, corticobasal syndrome, or posterior cortical atrophy were impaired on both dimensions; (ii) An association between both dimensions; (iii) that when sensory integration was controlled for, the frequency of apraxia decreased dramatically in some clinical subgroups. CONCLUSION: In a non-negligible portion of patients, the hypothesis of a disruption of sensory integration can be more parsimonious than the hypothesis of apraxia in case of impaired skilled gestures. Clinicians and researchers are advised to integrate sensory integration measures along with their evaluation of apraxia.

Associations between Adult Primary Brain Tumor Survivors' Behavioral Executive Functions, Health Related Quality of Life and their Caregivers' Health Related Quality : A cross-sectional study.

The present study focused on adult primary brain tumor (PBT) survivors' caregivers. The main objective was to study associations between PBT survivors' health-related quality of life (HRQOL), their behavioral executive functions (EF) and their caregivers' HRQOL. Forty PBT survivors of PBT and 37 caregivers (mostly patient's spouses 81.08%; n = 30) participated in the study. PBT survivors completed a cancer related Quality of Life (QOL) questionnaire. Caregivers completed informant rated HRQOL and behavioral EF reports relating to PBT survivors and a self-rated HRQOL questionnaire relating to themselves. Correlational and multiple regression analyses were conducted. No associations were found between caregivers' physical HRQOL and PBT survivors' HRQOL nor behavioral EF. Analyses yielded several significant correlations between caregivers' mental HRQOL and variables pertaining to PBT survivors' HRQOL and behavioral EF. Multiple regression analyses showed that caregivers' mental HRQOL is predicted by PBT survivors' mental HRQOL, global cancer-related QOL scores and global behavioral EF scores. This study provides evidence suggesting that during the survivorship phase, at an average of 3.67 (SD = 2.31) years following treatment for a PBT, caregivers mental HRQOL is linked to PBT survivors' long-term effects. These findings shed some light regarding post-cancer care for both PBT survivors and their caregivers.

Assessing the construct validity of a theory of mind battery adapted to Tunisian school-aged children.

Background: Theory of mind (ToM) refers to the ability to understand others' states of mind, desires, emotions, beliefs, and intentions to predict the content of their mental representations. Two major dimensions within ToM have been studied. The first is the type of inferred mental state, which can be cognitive or affective. The second comprises the types of processes involved according to their degree of complexity (first- and second-order false belief and advanced ToM). ToM acquisition is fundamental-a key component in the development of everyday human social interactions. ToM deficits have been reported in various neurodevelopmental disorders through various tools assessing disparate facets of social cognition. Nevertheless, Tunisian practitioners and researchers lack a linguistically and culturally appropriate psychometric tool for ToM assessment among school-aged children. Objective: To assess the construct validity of a translated and adapted French ToM Battery for Arabic-speaking Tunisian school-aged children. Methods: The focal ToM Battery was designed with neuropsychological and neurodevelopmental theory and composed of 10 subtests distributed evenly in three parts: Pre-conceptual, cognitive, and affective ToM. Translated and adapted to the Tunisian sociocultural context, this ToM battery was individually administered to 179 neurotypical Tunisian children (90 girls and 89 boys) aged 7-12 years. Results: After controlling for the age effect, construct validity was empirically confirmed on two dimensions (cognitive and affective) via structural equation modeling (SEM) analysis, demonstrating that this solution has a good fit. The results confirmed that the age affected differentially the performance obtained on ToM tasks based on the two components of the battery. Conclusion: Our findings confirm that the Tunisian version of the ToM Battery has robust construct validity for the assessment of cognitive and affective ToM in Tunisian school-aged children; hence, it could be adopted in clinical and research settings.

The role of cognitive estimation in understanding the mental states of others.

Previous studies have emphasized the critical role of the prefrontal cortex in cognitive estimation and theory of mind, however, none of them has questioned the possible role of cognitive estimation processes in understanding the mental states of others. In this study, we compared 30 patients with focal prefrontal cortex damage and 30 control subjects matched by gender, age, and education level on their performances on a cognitive estimation task and two tasks assessing theory of mind: the "Faux-Pas" task and the Reading the Mind in the Eyes task. The results showed that patients were significantly impaired compared with control subjects on both abilities of cognitive estimation and theory of mind. Moreover, regression analyses showed that performance on theory of mind was predicted by the scores on cognitive estimation. Finally, using voxel-based lesion analysis, we identified a partially common bilaterally distributed prefrontal network involved in both these domains centred within the ventral and dorsomedial areas with extension to the dorsolateral prefrontal cortex.

Imitation of meaningless gestures in the Alzheimer's disease: influence of egocentric and allocentric spatial reference frames / Imitation de gestes non significatifs dans la maladie d'Alzheimer : l'influence des cadres de référence spatiale égocentrique et allocentrique

Imitation of meaningless gestures is a frequently used task to assess praxis skills in Alzheimer's disease (AD). The visuospatial analysis is considered to be one of the cognitive mechanisms most involved in perceiving the gestures of the other (i.e. model to imitate) in the imitation of meaningless gestures. However, in order to perform a classic gesture imitation task (i.e. face model), it is also necessary to transpose the representation of the other's gestures to better represent one's own gestures. This transposition can be superimposed on the dichotomy of egocentric spatial reference frames (i.e. self-gestures) and allocentric spatial reference frames (i.e. gestures of the other). Given previous researches on the relation between hippocampus and allocentric performance, we predicted that AD patients could have imitation difficulties specifically for the allocentric imitation. We thus propose a specific methodology to evaluate the imitation of meaningless gestures in both egocentric and allocentric conditions using unimanual ( i.e. one hand gestures) as well bimanual (i.e. two hand gestures) gest modalities for each condition. Our results show significant differences between the AD group and control group, except under the bimanualallocentric condition. Moreover, correlation analyses with visuospatial assessments do not validate the essential role of visuospatial abilities in our gestural imitation tasks. The comparison of the within-group results shows a significant difference between egocentric and allocentric conditions only for the elderly control group suggesting that the impact of spatial reference frames in gestural imitation would not be specific to AD. However, one should also be alert to within-pathological variability in AD, which would require a future study with several subgroups of AD patients.

L'imitation de gestes non significatifs est une tâche fréquemment utilisée pour évaluer les aptitudes praxiques de la maladie d'Alzheimer (MA). L'analyse visuospatiale est considérée comme un des mécanismes cognitifs les plus impliqués dans l'imitation de gestes non significatifs pour percevoir les gestes de l'autre (i.e., modèle à imiter). Cependant pour réaliser une tâche d'imitation de gestes en forme classique (i.e., modèle situé de face), il est également nécessaire de transposer la représentation des gestes de l'autre pour mieux se représenter ses propres gestes. Cette transposition peut être superposée à la dichotomie de l'espace égocentrique (cf. gestes de soi) et l'espace allocentrique (cf. gestes de l'autre). Nous proposons ainsi une méthodologie spécifique afin d'évaluer l'imitation de gestes à la fois en condition égocentrique et en condition allocentrique. Nos résultats montrent des différences significatives entre le groupe MA et le groupe contrôle dans toutes les conditions sauf en condition allocentrique de la modalité bimanuelle (i.e., en deux mains). De plus, les analyses de corrélation avec des évaluations visuo-spatiales ne valident pas le rôle essentiel des capacités visuo-spatiales dans nos tâches d'imitation de gestes non significatifs. La comparaison des résultats en intragroupe montrent une différence significative entre les conditions égocentrique et allocentrique uniquement pour le groupe contrôle âgé, laissant supposer que l'impact des cadres de référence spatiale dans l'imitation de gestes ne serait pas spécifique à la MA. Toutefois, il faudrait également être attentif à une variabilité intrapathologique de la MA, ce qui requerrait une future étude avec plusieurs sous-groupes des patients MA.

Neurocognitive and neural mechanisms underlying deficit on the Reading Mind In The Eyes Task: Evidence from patients with focal prefrontal cortex damage.

OBJECTIVE: Conflicting evidence has arisen from the few correlational studies that have examined the relationship between the ability to decode social emotional cues through the eyes and executive functions in individuals with prefrontal cortex damage. The objective of the current study was (1) to investigate the impact of both focal prefrontal and parietal cortex damage on both of these domains; (2) to examine whether impaired ability to decode social emotion cues through the eyes was predicted by executive function deficits and; (3) to explore the neural correlates of both of these components. METHOD: Thirty individuals with prefrontal cortex damage, 15 individuals with parietal cortex damage and 30 matched healthy comparison subjects were subjected to a battery of executive tasks assessing inhibition, flexibility, and planning processes and the Reading the Mind in the Eyes Task (RMET) assessing ability to decode social emotion cues through the eyes. RESULTS: Compared to both comparison groups, individuals with prefrontal cortex damage were impaired in performing RMET and almost all executive tasks. Regression analysis showed that for individuals with prefrontal cortex damage, performance on the Stroop and Hayling tasks predicted scores on the RMET, while for the healthy comparison group, only the verbal fluency performance predicted scores on the RMET. The Voxel lesions-symptom mapping technique showed that both components rely partly on the same neural substrates, reflecting beyond the neural network of RMET per se that of the cognitive processes elicited by this multi-determinant task. CONCLUSION: These findings suggest that the ability to read mental states of mind depends on the inhibition and flexibility executive mechanisms.

Exploring behavioural and cognitive dysexecutive syndrome in patients with focal prefrontal cortex damage.

This study's objectives were to characterize the frequency and profile of behavioral and cognitive dysexecutive syndromes in patients with focal prefrontal cortex damage and how these syndromes overlap. We also examined the contribution of the prefrontal brain regions to these syndromes. Therefore, thirty patients with prefrontal cortex damage and thirty control subjects were compared on their performances using the GREFEX battery assessing the dysexecutive syndromes. The results showed that combined behavioral and cognitive dysexecutive syndrome was observed in 53.33%, while pure cognitive dysexecutive syndrome was observed in 20% and behavioral in 26.67%. Also, almost all behavioral and cognitive dysexecutive disorders discriminated frontal patients from controls. Moreover, correlations and regression analyses between task scores in both domains of dysexecutive syndromes showed that the spectrum of behavioral disorders was differentially associated with cognitive impairment of initiation, inhibition, generation, deduction, coordination, flexibility and the planning process. Furthermore, the patterns of cognitive and behavioral dysexecutive syndrome were both predictors of impairment in daily living activities and loss of autonomy. Finally, frontal regions contributing to different dysexecutive syndromes assessed by MRI voxel lesion symptom analysis indicate several overlapping regions centered on the ventromedial and dorsomedial prefrontal cortex for both domains of dysexecutive syndrome. This study concludes that damage to the frontal structures may lead to a diverse set of changes in both cognitive and behavioral domains which both contribute to loss of autonomy. The association of the ventromedial and dorsomedial prefrontal regions to both domains of dysexecutive syndrome suggests a higher integrative role of these regions in processing cognition and behavior.

Development of inhibition and working memory in school-age Moroccan children.

Studies regarding executive functions (EFs) in children rarely focus on populations of North Africa countries. In this context, this research aimed to adapt EFs tests to the Moroccan context and provide preliminary normative data on the development of inhibitory control and working memory (WM). In addition, the executive performance of school-age Moroccan children was examined, as well as the effects of gender, parents' education level and multilingualism. The sample included 115 children at age 7 to 12 from Fes city. Results showed that the translation and adaptation steps were sufficient for the cross-cultural adaptation of the tasks. In addition, an overall effect of age on inhibition and WM performances was found, whereas gender and parents' education level showed non-significant effects. Multilingualism effects had a partial positive influence on EFs, with improved scores on a few executive tasks for multilingual children compared to their bilingual peers. Overall, results suggest that EFs in school-age Moroccan children operate on relatively homogeneous development trajectories, marked by improvements that differ according to tasks. As neuropsychological tools and normative data are still lacking in Morocco, this study helps better understand EFs development of children in this country.

Assessing executive functions in Brazilian children: A critical review of available tools.

The goal of this review is to perform a critical analysis of the instruments used to assess executive functions (EFs) in preschool and school-age children in Brazil. We identified 37 assessment measures through a systematic review. Some performance-based tests for assessing working memory and inhibition were identified. However, there is a lack of rating measures and instruments to assess flexibility and planning in clinical practice. We observed regional differences in the performance of EFs measures. One possible explanation may be the use of normative samples from more highly-developed regions to characterize performance in less-developed regions. However, there may be alternative explanations, such as variations in the exposure to testing and the adequacy of test materials in different regions. Joint efforts among research groups should be encouraged in order to obtain normative references that are more representative of the socio-cultural diversity of the country. This improvement is essential to better understand the typical and atypical development of EFs and how the peculiarities of each country's context and culture can impact its trajectory.

Impaired Perception of Unintentional Transgression of Social Norms after Prefrontal Cortex Damage: Relationship to Decision Making, Emotion Recognition, and Executive Functions.

OBJECTIVE: Patients with prefrontal cortex damage often transgress social rules and show lower accuracy in identifying and explaining inappropriate social behavior. The objective of this study was to examine the relationship between the ability to perceive other unintentional transgressions of social norms and both decision making and emotion recognition as these abilities are critical for appropriate social behavior. METHOD: We examined a group of patients with focal prefrontal cortex damage (N = 28) and a group of matched control participants (N = 28) for their abilities to detect unintentional transgression of social norms using the "Faux-Pas" task of theory of mind, to make advantageous decisions on the Iowa gambling task, and to recognize basic emotions on the Ekman facial affect test. RESULTS: The group of patients with frontal lobe damage was impaired in all of these tasks compared with control participants. Moreover, all the "Faux-Pas", Iowa gambling, and emotion recognition tasks were significantly associated and predicted by executive measures of inhibition, flexibility, or planning. However, only measures from the Iowa gambling task were associated and predicted performance on the "Faux-Pas" task. These tasks were not associated with performance in recognition of basic emotions. These findings suggest that theory of mind, executive functions, and decision-making abilities act in an interdependent way for appropriate social behavior. However, theory of mind and emotion recognition seem to have distinct but additive effects upon social behavior. Results from VLSM analysis also corroborate these data by showing a partially overlapped prefrontal circuitry underlying these cognitive domains.

Age-related changes of cognitive flexibility and planning skills in school-age Moroccan children.

North African countries such as Morocco are scarcely the focus of neuropsychological studies, although the role of culture in cognition processes is widely recognized. Currently, studies on flexibility and planning skills in the Moroccan context are still lacking and there are no adapted tools to assess these functions in the country. In this scenario, this study aimed to adapt the Child Executive Functions Battery (CEF-B) tasks and the playing cards task of the Behavioral Assessment of the Dysexecutive Syndrome for Children (BADS-C) to Morocco and provide preliminary normative data on the development of flexibility and planning. In addition, this study proposed to examine the effects of gender, parents' education level and multilingualism on executive development. To this end, six tasks of the CEF-B were adapted through a translation and back-translation process and administered to 115 children aged 7-12 years. Results showed that the adopted procedure was sufficient for the cross-cultural adaptation of the tasks. Analyses showed a continuous increase with age on executive performance in most of the variables. However, gender and parents' level of education showed mostly non-significant effects. On the other hand, a significant effect of multilingualism was found on the two analyzed functions, with better results for multilingual children if compared to their bilingual peers. In general, results suggest that the identified pattern of development is consistent with international studies. Although normative data on executive functions are still lacking in Morocco, this unprecedented study will help better understand their development in this context.

Meaningless imitation in neurodegenerative diseases: Effects of body part, bimanual imitation, asymmetry, and body midline crossing.

Visuo-imitative apraxia has been consistently reported in patients with dementia, yet there have been substantial methodological differences between studies, while multiple, sometimes competing hypotheses have been put forward to explain this syndrome. Our goals were to study specific imitation deficits in groups of patients who have been selected and assigned to a group solely based on clinical criteria. We tested the effects of body part, bimanual imitation, asymmetry of the model, and body midline crossing, in patients with cortical atrophy of the temporal lobes (semantic dementia, SD), frontal-parietal networks (FPN, i.e., posterior cortical atrophy and corticobasal syndrome) or both (Alzheimer's disease, AD). Sixty-three patients and 32 healthy controls were asked to imitate 45 meaningless finger/hand, uni-/bimanual, asymmetrical/symmetrical, and crossed/uncrossed postures. SD patients had subnormal imitation scores. FPN patients showed frequent and marked deficits in most conditions, better performance with hand than finger postures (probably because of visuo-constructive deficits), and better performance with uncrossed than crossed configurations (probably because of body schema disorganization). Bimanual configurations were difficult for AD patients, not because of bimanual activity in itself, but rather because of the complexity of the model. The finding of dissociations in 34/63 cases (54%) suggests that some patients, even within the same clinical category, can have variable performance in imitation tests as a function of the abovementioned factors. Clinicians are advised to use tests with a large array of items to properly capture patients' imitation skills. This provides a new basis for future research to unpack which neurocognitive mechanisms are disrupted to cause specific patterns of impaired imitation.

Impaired social perception from eyes and face visual cues: evidence from prefrontal cortex damage.

Despite the key role that decoding of social-perceptual cues from faces plays in interpersonal communication, it is only recently that the potential of prefrontal cortex damage to disrupt this ability has been recognized. In fact, few studies to date had assessed whether the ability to identify the state of mind of others from the whole or part of the face is disrupted after prefrontal cortex damage and whether these two abilities are associated and share overlapped neural systems. In the present study, 30 patients with focal prefrontal lesions and 30 matched control subjects were assessed on their ability to recognize six basic emotions from facial expressions of the whole face and to identify states of mind of others from photographs of only the eyes using the "Reading the Mind in the Eyes Task". Results showed that frontal patients were significantly impaired compared with control subjects on both tasks. Moreover, regression analyses showed that these two abilities are associated and reciprocally predictive of one another. Finally, using voxel-based lesion analysis; we identified a partially common bilaterally distributed prefrontal network in the decoding of both emotional cues from both the whole face and eyes centered within the dorsomedial and ventral regions with extension to the lateral frontal pole.

The challenge of apraxia: Toward an operational definition?

The diagnosis of limb apraxia relies mainly on exclusion criteria (e.g., elementary motor or sensory deficits, aphasia). Due to the diversity of apraxia definitions and assessment methods, patients may or may not show apraxia depending on the chosen assessment method or theory, making the definition of apraxia somewhat arbitrary. As a result, "apraxia" may be diagnosed in patients with different cognitive impairments. Based on a quantitative and critical review of the literature, it is argued that this situation has its roots in the evolution from a task-based approach (i.e., the use of gold standard tests to detect apraxia) toward a process-based approach, namely, the deconstruction of the conceptual or production systems of action into multiple cognitive processes: language, executive functions, working memory, semantic memory, body schema, body image, visual-spatial skills, social cognition, visual-kinesthetic engrams, manipulation knowledge, technical reasoning, structural inference, and categorical apprehension. The coexistence of both approaches in the current literature is a major challenge that stands in the way of a scientific definition of apraxia. As a step toward a solution, we suggest to focus on symptoms, and on two complementary definition criteria (in addition with traditional exclusion criteria): Specificity (i.e., is apraxia explained by the alteration of cognitive processes specifically dedicated to gesture production?), and consistency (i.e., is the gesture production impairment consistent across tasks?). Two categories of limb apraxia are proposed: symptomatic apraxia (i.e., gesture production deficits that are secondary to more general cognitive impairments) and idiopathic apraxia (i.e., gesture production deficits that can be observed in isolation). It turns out that the only apraxia subtype that fulfills exclusion, specificity, and consistency criteria is limb-kinetic apraxia. A century after Liepmann's demonstration of the autonomy of apraxia toward language, the autonomy of this syndrome toward the rest of cognition remains an open question, while it poses new challenges to apraxia studies.

Development of executive functions in Lebanese children.

The current study focused on adapting EF tests for children to the Arabic language and examine the developmental trajectories of a sample of school-aged Lebanese children in four domains of EF (inhibition, flexibility, working memory, and planning). It also focused on examining the effects of gender and parental education level on EF performance. The study population included 100 Lebanese children aged from 6 to 12-years old who were grouped and comparable for age, gender, and parental level of education. Results revealed a main effect of age and level of education of parents while the effect of gender was non-significant.