Define aphasia.

• A. Loss or impairment of memory.
• B. Loss or impairment of the ability to understand or express language.
• C. Pain sensation loss
• D. Inability to taste

Answer: (B)

Aphasia is a language disorder caused by brain injury that disrupts the ability to understand and/or express language. It can affect speaking, understanding spoken language, reading, and writing, depending on which parts of the brain are damaged. This makes the choice describing loss or impairment of understanding or expressing language the best fit. The other options refer to different senses or functions—memory loss (amnesia), loss of pain sensation (anesthesia), and loss of taste (ageusia)—which are not about language processing. Aphasia often results from stroke or head injury, most commonly affecting the language-dominant left hemisphere, and there are forms where speech is difficult to produce (expressive aphasia) or where understanding is impaired (receptive aphasia).