Brain activity index of distractibility in normal school-age children

Children's attention is easily diverted from a current activity to a new ev ent in the environment. This was indexed in school-age children by diminish ed performance speed and accuracy in a visual discrimination task caused by task-irrelevant novel sounds. Event-related brain potentials (ERPs) elicit ed by these distracting sounds showed a prominent positive deflection that was generated by brain processes associated with involuntary switching of a ttention to novel sounds. Recordings of the magnetoencephalographic (MEG) c ounterpart of this brain activity revealed a major bilateral generator sour ce in the superior temporal cortex. However, ERP scalp distributions indica ted also overlapping brain activity generated in other brain areas involved in involuntary attention switching. Moreover, differences in ERP amplitude s and in their correlations with the reaction times between younger (7-10 y ears) and older (11-13 years) children indicated developmental changes in a ttentional brain functions. (C) 2001 Elsevier Science Ireland Ltd. All righ ts reserved.