Wernicke's area receives information from the auditory cortex, and functions to assign word meanings. This is why damage to this area results in meaningless speech, often with paraphasic errors and newly created words or expressions. Paraphasia can involve substituting one word for another, known as semantic paraphasia, or substituting one sound or syllable for another, defined as phonemic paraphasia. This speech is often referred to as “word salad,” as speech sounds fluent but does not have sensible meaning. Normal sentence structure and prosody are preserved, with normal intonation, inflection, rate, and rhythm. This differs from Broca's aphasia, which is characterized by nonfluency. Patients are typically not aware that their speech is impaired in this way, as they have altered comprehension of their speech. Written language, reading, and repetition are affected as well.