Stroke-induced aphasia refers to the inability to speak or unclear speech.
Based on anatomical knowledge of the brain, it is recognized that stroke-induced aphasia caused by cerebrovascular diseases is the result of damage to the cerebral cortex. Clinically, it can be divided into motor aphasia, sensory aphasia, naming aphasia, and semantic aphasia according to the damaged area of the cerebral cortex. If two or more types of aphasia occur simultaneously, it is called mixed aphasia.
What is motor aphasia?
Motor aphasia occurs when the fronto-inferior region of the cerebral cortex, also known as the motor speech center, is stimulated or damaged by either cerebral hemorrhage or thrombosis. Patients with motor aphasia can understand what others are saying, but cannot speak for themselves.
What is semantic aphasia?
Semantic aphasia occurs when the junction of the three lobes of the cerebral cortex (temporal, parietal, and occipital) is stimulated pathologically. This part of the cerebral cortex is responsible for integrating visual, auditory, and linguistic information to generate semantics, as well as speech symbols and syntactic codes that can express these semantics. The characteristic of semantic aphasia is the inability to understand complex grammatical structures. For example, patients cannot distinguish the meanings of “brother’s father” and “father’s brother.” They cannot comprehend passive voice sentences like “The apple was eaten by the child,” resulting in confusion about who ate whom.
What is sensory aphasia?
Sensory aphasia occurs when the posterior part of the temporal lobe, which is the sensory language center, is stimulated by the lesion in stroke patients. That is, patients can speak autonomously, but they are unclear about the meaning of their own words, and they cannot understand what others are saying. Therefore, they often give answers that are not relevant to the question, and their language has no logicality and even babbles. In this situation, relatives and others should show sympathy and understanding towards the patient, realizing that this is a pathological condition. Only through active treatment can sensory aphasia gradually recover.
What is nominal aphasia?
Nominal aphasia occurs when the posterior part of the temporal lobe and the inferior part of the parietal lobe are damaged. Patients lose the ability to name objects and can only describe their purposes instead of their names. For example, when showing a pencil, the patient can only say it is a “writing tool” but cannot call it a “pencil.”
