In medicine and neurology, receptive aphasia or Wernicke's aphasia is a subclass of fluent aphasias in which individuals have difficulty understanding written and spoken language because of damage to a distributed network of brain regions involved in language comprehension rather than a single isolated area. Patients with Wernicke's aphasia often have fluent speech, which is characterized by typical speech rate and effortless speech output, but the content may lack meaning or include incorrect or made-up words. Writing often reflects speech by lacking substantive content or meaning, and may contain paraphasias or neologisms, similar to how spoken language is affected. In most cases, motor deficits (i.e., hemiparesis) do not occur in individuals with Wernicke's aphasia. Therefore, they may produce a large amount of speech without much meaning. Individuals with Wernicke's aphasia commonly show anosognosia, meaning they may be unaware of their errors in speech and may not realize that their spoken language lacks meaning. They typically remain unaware of even their most profound language deficits. Like many acquired language disorders, Wernicke's aphasia can be experienced in many different ways and to many different degrees. Patients diagnosed with Wernicke's aphasia can show severe language comprehension deficits; however, this is dependent on the severity and extent of the lesion. Severity levels may range from being unable to understand even the simplest spoken and/or written information to missing minor details of a conversation. Many diagnosed with Wernicke's aphasia have difficulty with repetition in words and sentences and/or working memory. Wernicke's aphasia was named after German physician Carl Wernicke, who is credited with discovering the area of the brain responsible for language comprehension (Wernicke's area) and discovery of the condition which results from a lesion to this brain area (Wernicke's aphasia). Although Wernicke's area (left posterior superior temporal cortex) is known as the language comprehension area of the brain, defining the exact region of the brain is a more complicated issue. A 2016 study asked neuroscientists what portion of the brain they consider to be Wernicke's area, and results suggested that the classic "Wernicke–Lichtheim–Geschwind" model does not fully account for modern evidence about the distributed network of cortical and subcortical regions involved in language processing. This is because this model was created using an old understanding of human brain anatomy and does not take into consideration the cortical and subcortical structures responsible for language or the connectivity of brain areas necessary for production and comprehension of language. While there is no single, well-defined area solely responsible for language comprehension, Wernicke's aphasia is a well-documented clinical condition in which individuals have difficulty understanding language due to damage in key parts of the language network. A better way to describe aphasia is fluent or non-fluent rather than "expressive" or "receptive" given the typical presence of both expressive and receptive language deficits in all subtypes of aphasia.
Signs and symptoms People with Wernicke's aphasia often produce fluent but disorganized speech. Such speech may contain neologisms (made-up words) and semantic paraphasias (word substitutions). Although their speech sounds fluent, it can be difficult to follow because the content lacks meaning. The following are common symptoms seen in patients with Wernicke's aphasia:
… excerpt ends here. Continue reading the full article.
