APA Dictionary of Psychology

a set of nonprogressive movement and posture disorders that result from trauma to the brain occurring prenatally, during the birth process, or before the age of 5. Symptoms include spasticity, uncontrolled movements (see athetosis), paralysis, unsteady gait, and speech abnormalities (see dysarthria) but may be accompanied by other neurological symptoms, including cognitive changes, seizures, impaired vision, tactile impairment, hearing loss, and intellectual developmental disorder. CP is commonly classified into the following types: spastic, the most common, resulting from damage to the motor cortex, corticospinal tract, or pyramidal tract; dyskinetic, resulting from damage to the basal ganglia; ataxic, resulting from damage to the cerebellum; and mixed, in which more than one type is evident.