Motor Aphasia Loss of Expressive Speech Impairment of expressive language and relative preservation of receptive language abilities. That is, the patient understands language (speech, writing) but cannot express it. Aphasia is caused by damage to parts of the brain responsible for understanding and using language. Common causes include:stroke, thought to be the most common cause, around one in three people experience some degree of aphasia after having a stroke.severe head injury. brain tumour.progressive neurological conditions (conditions that over time cause progressive brain and nervous system damage). Experience difficulties with understanding or expressing language. HP:0002427 Aphasia is one of the most common communication disorders to affect the brain. Although there are no official figures, the Stroke Association estimates more than 376,000 stroke survivors in the UK are living with aphasia. Aphasia can affect people of all ages, including children. It's most common in people over 65 years old as stroke and common progressive neurological conditions tend to affect older adults SCDO:0000773 Broca's Aphasia Sufficient Expressive Aphasia Abnormal Nervous System Physiology