What type of cerebral palsy is characterized by slow writhing movements in an infant?

The type of cerebral palsy characterized by slow writhing movements in an infant is athetoid cerebral palsy. This condition results from lesions in the basal ganglia, which are responsible for controlling the smoothness and timing of movements. In children with athetoid cerebral palsy, the muscle tone can be fluctuating, leading to both hypotonia and hypertonia. The hallmark of this type is the presence of involuntary movements, which can be described as slow, twisting, or writhing motions. These movements typically affect the limbs and often hinder voluntary motor control, making it difficult for the child to maintain a stable posture or perform coordinated movements.

In contrast, spastic cerebral palsy is characterized by increased muscle tone and stiffness, leading to jerky and awkward movements. Ataxic cerebral palsy involves problems with balance and coordination, leading to unsteady gait and difficulty in fine motor tasks. Mixed cerebral palsy can exhibit characteristics of more than one type, combining elements of spastic and athetoid or other movement patterns. Athetoid cerebral palsy specifically stands out for its unique presentation of slow, writhing movements, making it the correct choice for this question.