Dyslogic syndrome, sometimes referred to as developmental or congenital aphasia, consists of the inability to express oneself through language due to a central nervous system dysfunction. Symptoms may not be the result of a sensory or cognitive deficit, nor may they occur due to loss of prior linguistic abilities. The primary characteristic of dyslogia is difficulty with communication, which is likely to make learning more difficult and to cause frustration to the child. At times children with dyslogia may be misdiagnosed with mental retardation, deafness, auditory deficit, or psychological disorder due to similarities in behavioral patterns. True dyslogia is believed to be quite rare, although epidemiological information is not available.