Cortical thickness and global/local visual abilities in children
Résumé
A visual scene consists of local elements (trees) that are arranged into a global configuration (a forest). Paradigms using large global forms composed of suitable arrangements of small local forms revealed a global precedence effect in adults, characterized by a global advantage (faster detection of global information than local parts) and an interference from global information during local processing. Even if behavioral studies evidenced a global precedence from 9 years of age, cortical structures underlying global precedence and global interference effects are still unknown in healthy children. In the present work, after a MRI session in a 3-Tesla MRI scanner, 10 years-old children were presented with a classic global/local selective attention task with congruent and incongruent conditions. Regression analyses (p<.01) between cortical thickness estimation (Destrieux Atlas) and responses times to global/local task showed thinner cortical thickness associated with a weaker global advantage in right frontal (middle, inferior and opercular parts) and in right temporal pole regions. A thinner cortical thickness was also associate with (1) increasing ability to deal with interference from local information in the right middle frontal cortex and (2) increasing ability to deal with interference from global information in right frontal middle, frontal inferior and orbital bi-lateral sulcus. The mainly right lateralized frontal network evidenced in the present work that allow children to efficiently deal with global/local visual information have potential implications for models of attentional selection and executive control.