Which of the following best defines aphasia?

Aphasia is a language disorder that impacts an individual’s ability to express and understand language. It can manifest as difficulties in speaking, writing, reading, or comprehending spoken language. This condition often arises due to brain damage, typically from a stroke or traumatic injury, which affects the language centers of the brain.

The definition encompasses both expressive language difficulties, where a person struggles to form meaningful sentences or may find it challenging to find specific words, and receptive language difficulties, where they might have trouble understanding what others are saying. This dual impact on both expression and reception of language distinguishes aphasia from other disorders that may affect sensory or motor functions.

In contrast, other options refer to various physical or sensory impairments not related to language. For example, a disorder affecting vision focuses on the visual system rather than language function. Similarly, a disorder of motor coordination pertains to physical movement and muscle control, while a condition affecting balance and movement is also unrelated to language processing. Hence, the correct definition of aphasia is specifically tied to language deficits, making the chosen answer the most accurate.