The mediating role of cognitive ability on the relationship between motor proficiency and early academic achievement in children.

The aim of this study was to examine the relationship between motor proficiency and academic achievement in 7 years-old children. A mediating model in which the relation between motor proficiency and academic achievement is mediated by cognitive ability was tested. Participants included 152 children from the longitudinal study Jeunes enfants et leurs milieux de vie (Young Children and their Environments). Motor proficiency was evaluated with the Bruininks-Oseretsky Test of Motor Proficiency (BOT2), cognitive ability with the Wechsler Intelligence Scale for Children-Fourth Edition (WISC-IV) and academic achievement with the Wechsler Individual Achievement Test II (WIAT II). Results showed that motor proficiency, cognitive ability and academic achievement were positively correlated with each other. A structural equation modeling analysis revealed that motor proficiency had a positive effect on academic achievement through an indirect path via cognitive ability. These results highlight the fundamental importance of motor skills in children's academic achievement in early school years.

Complexity and hemispheric abilities: evidence for a differential impact on semantics and phonology.

The main goal of this study was to determine whether the phonological and semantic processing of words are similarly influenced by an increase in processing complexity. Thirty-six French-speaking young adults performed both semantic and phonological word judgment tasks, using a divided visual field procedure. The phonological complexity of words was controlled by varying their transparency, while semantic complexity was manipulated through prototypicality. As expected, processing complexity modulated semantic and phonological processing differently. The results revealed that an increase in processing complexity lessened the left-hemisphere advantage in semantics, but reinforced it in phonology. It is therefore suggested that right-hemisphere collaboration in complex language processing is profitable only when the particular kind of processing is not strongly lateralized to the left-hemisphere. The results are discussed from the perspective of interhemispheric collaboration.

Phonological and semantic processing of words: laterality changes according to gender in right- and left-handers.

The ability of cerebral hemispheres to process language is influenced by multiple factors. The well-known right visual field advantage in word recognition in divided visual field tasks is affected by both intra- and inter-individual variables. For example, hemispheric linguistic abilities may vary within a given individual according to the language component being processed, whereas variations between individuals may be modulated by the individual's handedness and gender. The objective of this divided visual field study was to compare gender differences in right- and left-handers in relation to their hemispheric abilities in performing phonological and semantic tasks. The results indicate that for both types of processing, gender had a different impact on right- and left-handed groups. Unexpectedly, a gender difference in laterality pattern was found in left-handers but not in right-handers for both phonological and semantic abilities. Intriguingly, left-handed men displayed a more symmetrical laterality pattern in phonological and semantic abilities than left-handed women.

Real-life spatial skills, handedness, and family history of handedness.

According to , pronounced left hemisphere lateralization for language abilities in women, as in female absolute right-handers, limits their right hemisphere capacity and spatial abilities. This study examines the degree of handedness and the family history of non-right-handedness with respect to real-life spatial abilities in women. Twenty-four women had, first, to learn a new route and, second, to orient themselves within a labyrinth. In the former task, the number of errors and completion time were evaluated; in the latter task, degree of error for orienting was recorded. The results show that, contrary to Annett's prediction, right-handers with and without a family history of non-right-handedness did not differ on these measures. In addition, and unexpectedly, absolute right-handers were found to surpass non-absolute ones in the spatial orientation task. These findings do not support Annett's hypothesis and are discussed in relation to functional cerebral organization.

Phonological processing of words in right- and left-handers.

It is commonly accepted that phonology is the exclusive domain of the left hemisphere. However, this pattern of lateralization, which posits a right visual field advantage, has been questioned by several studies. In fact, certain factors such as characteristics of the stimuli and subjects' handedness can modulate the right visual field advantage. Thus, the goal of this study was to compare the hemispheric dynamics of right-handers and left-handers during a divided visual field presentation of words that varied in terms of their phonological transparency. For non-transparent words, the left hemisphere seems more competent in both handedness groups. With regard to transparent words, the right hemisphere of both groups also appears competent. Surprisingly, left-handers achieved optimal processing with a functionally isolated left hemisphere, whereas right-handers needed the participation of both hemispheres. The pattern of performance cannot be fully explained by either the callosal or the direct access model.

Semantic processing of words, cognitive resources and N400: an event-related potentials study.

The specificity of the right hemisphere (RH) contribution to the semantic processing of words is still debated. Indeed, the semantic impairments of right hemisphere damaged (RHD) subjects may be the expression of limited general cognitive resources rather than a specific impairment of semantic processing ([Monetta et al., 2001]; [Murray, 2000]). The purpose of this study was to evaluate the possibility that the N400 reflect the availability of cognitive resources through an analysis of its different amplitudes according to different semantic complexity level. Ten young adults without any history of neurological damage participated in a semantic categorization task with two different levels of difficulty based on prototypicality. Event related potential (ERP) signals from 64 electrodes were recorded. An N400 was observed during the processing of difficult words and distractors. The results show that the greatest N400 activation was observed during the processing of difficult words, thus reflecting a possible increase in the amount of required cognitive resources.