This protocol aims to develop paradigms to identify the neural networks that underlie language processing in pre/early literate children. These studies are designed to test the hypothesis that language networks are strongly lateralized and regionally specific in children younger than eight. The study extends our investigations of paradigm development and language network organization in adults and older children (8-12) to the 4-7 year age group. Word reading, object naming, and auditory comprehension paradigms will be adapted for children 4-7 years old. Paradigm stimuli will be devised from pilot data obtained under protocol 01-N-181. Paradigms will be piloted in adults and older children (8-12 years) before young child studies (4-7 years) and will employ the 1.5 and 3T scanners. Paradigms will be designed to overcome limitations in previous studies: monitoring performance in the scanner, using 3T and event related designs to improve signal to noise and allow data analysis in relation to task item response, and improve motion correction, using language neutral control conditions, and using paradigms appropriate for pre-literate children. Data will be analyzed on an individual basis with AFNI and group analysis with SPM 99 using random effect analysis to identify brain regions associated with task performance. These paradigms will be used as language probes for other protocols designed to study the effect of acute and chronic disease states (e.g. stroke and epilepsy) on the plasticity of neuronal organization in language networks. In order to compare two non-invasive language mapping modes, we will perform magnetoencephalography with auditory category and description decision tasks.