apraxias

Apraxia is a neurological disorder characterized by an impaired ability to perform purposeful movements or gestures despite having the desire and the physical capacity to do so. The difficulty lies in planning and programming the motor sequences needed for skilled actions, rather than in weakness, sensory loss, or language comprehension.

Non-speech apraxias include several subtypes: ideomotor apraxia, ideational apraxia, limb-kinetic apraxia, buccofacial apraxia, constructional apraxia, and dressing apraxia. Ideomotor apraxia is the inability to perform an action on command despite understanding the gesture and being able to perform it spontaneously. Ideational apraxia involves a disruption in the conceptual sequence of actions, leading to errors in how to use objects. Limb-kinetic apraxia refers to clumsy, imprecise movements of the limbs. Buccofacial apraxia affects purposeful movements of the face and mouth. Constructional apraxia impairs drawing, building, or assembling, while dressing apraxia impairs clothing, often due to disturbances in body schema or spatial organization. Apraxia of speech is a related, distinct disorder of planning the movements for speaking, separate from muscle weakness (dysarthria).

Causes typically include stroke, traumatic brain injury, tumors, and progressive neurodegenerative diseases. It most often relates to left-hemisphere damage involving frontal and parietal networks that coordinate motor planning and execution.

Assessment involves comparing performance on instructed actions versus spontaneous use, imitation, and pantomime with objects, often supplemented by imaging. Treatment usually combines occupational therapy, speech-language therapy, and compensatory strategies such as breaking tasks into steps, providing cues, and using repetitive practice to improve performance. Prognosis depends on the underlying cause and lesion location.