Families with auditory temporal processing deficits are sought in order to identify the genes responsible for auditory temporal processing deficits. Children and adults with a diagnosis or history of language impairment in the family and their family members both affected and non-affected are eligible for this two-part study. In Part 1, participants undergo a series of language tests and listening tests to measure various characteristics of how they perceive sound. In Part 2, they are interviewed about language disorders, learning disabilities, and other medical problems of family members. This information is used to construct a pedigree (family tree diagram) showing the pattern of inheritance of family traits. Study subjects whose pedigree indicates that language disorders may be hereditary in their family will provide either a small blood sample (1 to 2 tablespoons) or a tissue specimen obtained from a cheek swab (rubbing the inside of the cheek with a small brush or cotton swabs). The sample will be used to isolate DNA for genetic analysis.