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Objective: It was hypothesized that neuropsychological impairments in children with neurofibromatosis type I (NF1) are associated with brain areas of increased T2-weighted signal intensity on MRI. Systematic and extensive examination of this hypothesis remains however scarce, particularly regarding executive dysfunction whereas hyperintensities are located preferentially in frontal-sub-cortical networks. In this study, we compared the executive functioning profile with characteristics of brain hyperintensities in children with NF1., Method: A sample of 36 school-age children with NF1 (7-12 years) underwent a detailed examination of executive function, including performance-based tests and child's behavior rating in daily life. Executive function measures were compared with the characteristics of the T2-weighted hyperintensities on parallel MRI scans. The presence, number, and size of hyperintensities in the whole brain were considered as well as their main cerebral locations., Results: Executive dysfunction including traditional cognitive and ecological measures in children with NF1 is not significantly influenced by T2-weighted hyperintensities, in terms of presence or not, number, size, and location, whether in the whole brain or according to involved specific brain areas., Conclusion: T2-weighted hyperintensities, as they are currently measured, cannot be used as a strong indicator of executive dysfunction in children with NF1. Based on the available NF1 cognitive impairment pathogenesis models, a critical discussion on anatomical-functional relationships between hyperintensities and neuropsychological profile is proposed, especially the executive dysfunction., ((c) 2015 APA, all rights reserved).)

Apraxia is one of the cognitive deficits that characterizes Alzheimer's disease. Despite its prevalence and relevance to diagnosing Alzheimer's disease, this topic has received little attention and is without comprehensive review. The review herein is aimed to fill this gap by first presenting an overview of the impairment caused in different clinical situations: pantomime of tool use, single tool use, real tool use, mechanical problem solving, function and manipulation knowledge tasks, and symbolic/meaningless gestures. On the basis of these results, we then propose alternative interpretations regarding the nature of the underlying mechanisms impaired by the disease. Also presented are principal methodological issues precluding firm conclusions from being drawn.

Objective: The main aim of this study was to investigate the effects of Huntington's disease (HD) on cognitive and affective Theory of Mind (ToM) abilities. The relation of ToM performance and executive functions was also examined., Method: Eighteen HD patients, early in the course of the disease, and 18 healthy volunteers matched for age and educational levels, were given two tasks: a nonverbal cognitive ToM task assessing attribution of intentions to others and a revised version of the 'Reading the Mind in the Eyes' test, which is an affective ToM task assessing the understanding of other people's mental states from their eyes. Participants were also given various executive tests., Results: The two ToM tasks revealed a significant impairment of ToM abilities in HD patients. Executive functioning was impaired in the HD group and ToM performance on the attribution of intentions task was dependent on several executive processes., Conclusions: Our results are consistent with the idea that both cognitive and affective aspects of ToM could be impaired in HD patients, indicating that cortico-subcortical circuits are underlying higher social functions such as ToM. The results are also consistent with the idea that only a few executive mechanisms regulate the ToM abilities we tested in this work. They also provide a basis for the understanding of the disorganized behavior and the breakdown of interpersonal relationships in daily life after HD.

The effects on comprehension of presenting medical prescription information in a pictorial format were compared to a verbal format in healthy old adults and in patients suffering from Alzheimer disease (AD). Participants received medical prescription instructions in one of two formats: with verbal instructions only, or with verbal instructions associated with pictorial representations. The results indicated that comprehension for prescription information of healthy old subjects and AD patients was facilitated by the combined presentation. Furthermore, the pictorial instructions appeared acting on the capacity to work out a specific medication schemata, that is to say on their real, operational, understanding. These results suggest that analogical pictorial format leads more directly to the medical prescriptions' situation model and alleviates the particularization deficiency of the therapeutic schemata, independently of global cognitive functioning, visual perception, space perception and visual semantic analysis in AD. The presentation of illustrations representing medical prescriptions would allow to decrease doubts and errors, which are frequent in normal aging and even more in Alzheimer's disease, and contribute to a better medical compliency.

Unlabelled: Recent studies suggest that executive functions are among the first cognitive functions to decline with normal aging., Methods: We studied the effect of age on executive functions using a set of 13 arithmetic word problems including 9 problems of increasing complexity which were solvable in 2, 3, 4 operations, and 4 aberrant problems. Three groups participated in the study: 18 young, 18 adult and 18 elderly participants., Results: The results showed that elderly participants were more impaired to resolve complex arithmetic word problems, without deficit in their ability to eliminate aberrant problems., Conclusion: The current elderly sample has a dissociated pattern of performance similar to that of some patients with frontal lobe lesions. In these patients, relations were found between the inability to generate correct algorithms of resolution for arithmetic word problems of increasing complexity and lesions in the dorsolateral prefrontal cortex, and between the impaired inhibition of unsolvable word problems and lesions in the orbitofrontal regions. We suggest that cognitive aging could be better interpreted in terms of changes in some frontal systems rather than in all-encompassing frontal deterioration.

The aim of the present study was to determine whether monitoring measures are differentially disturbed in dysexecutive patients after frontal lesions. Twelve dysexecutive patients and 12 healthy controls were administered a paired-associates learning task. Their performances on recall prediction, judgment-of-learning (JOL), and feeling-of-knowing judgment (FOK) were then compared. The results revealed that the two groups differed only on accuracy measures of the FOK paradigm. The study of the overall correlations between the three measures of metamemory revealed a significant relation between recall prediction and accuracy measures of the JOL. We failed to find any significant correlation with the accuracy measures of the FOK. Taken together, our data confirm that metamemory experience is not a unitary construct but rather a group of distinct and quite independent mechanisms.

The purpose of this study was to examine executive functioning in patients with Huntington's disease using an arithmetic word-problem-solving task including eight solvable problems of increasing complexity and four aberrant problems. Ten patients with Huntington's disease and 12 normal control subjects matched by age and education were tested. Patients with Huntington's disease performed the solvable problems significantly worse than the normal control subjects, but there was no difference in performance between the two groups in inhibiting aberrant problems. These results suggest that early Huntington's disease patients exhibit a precocious impairment in their ability to plan the resolution of complex arithmetic word problems without deficit in their ability to eliminate aberrant problems. This dissociation of performance fits with what we have found in such patients using script-sequencing tasks (Allain et al., 2004) and with neuropsychological data obtained by Watkins et al. (2000). These results are consistent with what is known about the neuropathological progression of Huntington's disease in which neuronal loss progresses in a dorso-to-ventral direction and with what was shown in patients with circumscribed frontal lobe damage. In these patients, impairments in planning solvable word problems were more frequent when lesions were in the lateral prefrontal regions.

A particularly important aspect of executive functioning involves the ability to form and carry out complex plans, that is to say planning. This study aimed to investigate planning in 18 older and 16 younger normal participants using an ecological planning subtask derived from the Behavioural Assessment of the Dysexecutive Syndrome test battery, the "Zoo Map Test." There are two trials. The first trial consists of a "high demand" version of the subtask in which the participants must plan in advance the order in which they will visit designated locations in a zoo (formulation level). In the second, or "low demand" version, the participant is simply required to follow a concrete externally imposed strategy to reach the locations to visit (execution level). The two-way ANOVAs mainly showed more difficulties in elderly adults than in younger adults, more difficulties in formulation level than in execution level, and lastly a greater difference between formulation and execution in older participants than in younger adults. These results suggest that elderly participants have some problems developing logical strategies whereas they are able to execute complex predetermined plans.

The present investigation examined the functioning of inhibitory mechanisms in younger and older bilinguals using a bilingual version of the Stroop test. The study predicted different patterns of age related decline in inhibitory mechanisms (inter- and intralingual interference) in bilinguals depending on their level of proficiency. Consistent with expectations, older bilinguals were slower when they responded in their non-dominant language. Furthermore, older unbalanced bilinguals showed greater interlingual interference when they responded with their second language to visual stimuli written in their dominant language. Balanced bilinguals showed equivalent interference effects between all conditions. These findings suggest that manipulating two languages may enhance the efficiency of inhibitory mechanisms.

Apraxia is the inability to carry out a motor act despite intact motor and sensory systems, good comprehension, and full cooperation. Performance in gesture processing tests is generally rendered by classifying patients's profile according to the classic clinical labels of ideomotor and ideational apraxia. Recently cognitive neuropsychological models allow to get a better understanding of the complexity of limb apraxia. In this paper, we studied ideomotor and ideational apraxia with a cognitivist approach in examination. Dressing and constructional apraxias will be also described in this paper.