Dysphasia is a speech disorder in which there is an impairment of speech and of comprehension of speech. It is caused by brain damage, usually in the left side of the brain which is responsible for language and communication.
The term dysphasia has been eclipsed by the modern usage of the term "aphasia" particularly in the field of speech/language pathology so as not to confuse with the swallowing disorder "dysphagia." Aphasia literally means no speech. But the speech impairment in aphasia could range from complete absence of speech to difficulty in naming a few objects. Aphasia is generally tested on the basis of comprehension of speech, fluency of speech, repetition and naming of objects. On this basis, aphasia can be classified as global aphasia, wernicke's aphasia, broca's aphasia, conduction aphasia, transcortical motor aphasia, transcortical sensory aphasia, anomic aphasia.