It is difficult to predict exactly the milestones and challenges a person diagnosed with a DCC will have. Some parents notice milestones are not met as infants or toddlers. Other parents notice differences as a child progress through the early years of school. Behaviorally individuals with DCC may fall behind their peers in social and problem-solving skills in elementary school or as they approach adolescence. In typical development, the fibers of the corpus callosum become more efficient as children approach adolescence. At that point children with an intact corpus callosum show rapid gains in abstract reasoning, problem solving, and social comprehension. Although a child with DCC may have kept up with his or her peers until this age, as the peer-group begins to make use of an increasingly efficient corpus callosum, the child with DCC falls behind in mental and social functioning. In this way, the behavioral challenges for individuals with DCC may become more evident as they grow into adolescence and young adulthood.