Receptive aphasia
Wernicke's aphasia, also known as receptive aphasia, sensory aphasia or posterior aphasia, is a type of aphasia in which individuals have difficulty understanding written and spoken language. Patients with Wernicke's aphasia demonstrate fluent speech, which is characterized by typical speech rate, intact syntactic abilities and effortless speech output. Writing often reflects speech in that it tends to lack content or meaning. 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 are typically  unaware of their errors in speech and do not realize their speech may lack 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). Signs and symptoms. The following are common symptoms seen in patients with Wernicke's aphasia: How to differentiate from other types of aphasia Causes. The most common cause of Wernicke's aphasia is stroke. Strokes may occur when blood flow to the brain is completely interrupted or severely reduced. This has a direct effect on the amount of oxygen and nutrients being able  to supply the brain, which causes brain cells to die within minutes. "The middle cerebral arteries supply blood to the cortical areas involved in speech, language and swallowing. The left middle cerebral artery provides Broca's area, Wernicke's area, Heschl's gyrus, and the angular gyrus with blood". Therefore, in patients with Wernicke's aphasia, there is typically an occlusion to the left middle cerebral artery. As a result of the occlusion in the left middle cerebral artery, Wernicke's aphasia is most commonly caused by a lesion in the posterior superior temporal gyrus (Wernicke's area). This area  is posterior to the primary auditory cortex (PAC) which is responsible for decoding individual speech sounds. Wernicke's primary responsibility is to assign meaning to these speech sounds. The extent of the lesion will determine the severity of the patients deficits related to language. Damage to the surrounding areas (perisylvian region) may also result in Wernicke's aphasia symptoms due to variation in individual neuroanatomical structure and any co-occurring damage in adjacent areas of the brain. Diagnosis. Aphasia is usually first recognized by the physician who treats the person for his or her brain injury. Most individuals will undergo  a magnetic resonance imaging (MRI) or computed tomography (CT) scan to confirm the presence of a brain injury and to identify its precise location. In circumstances where a person is showing possible signs of aphasia, the physician will refer him or her to a speech-language pathologist (SLP) for a comprehensive speech and language evaluation. SLPs will examine the individual's ability to express him or herself through speech, understand language in written and spoken forms, write independently, and perform socially. The American Speech, Language, Hearing Association (ASHA) states a comprehensive assessment should be conducted in order to analyze the  patient's communication functioning on multiple levels; as well as the effect of possible communication deficits on activities of daily living. Typical components of an aphasia assessment include: case history, self report, oral-motor examination, language skills, identification of environmental and personal factors, and the assessment results. A comprehensive aphasia assessment includes both formal and informal measures. Formal assessments include: Informal assessments, which aid in the diagnosis of patients with suspected aphasia, include: Diagnostic information should be scored and analyzed appropriately. Treatment plans and individual goals should be developed based on diagnostic information, as well as patient and caregiver needs , desires, and priorities. Treatment. According to Bates et al. (2005), "the primary goal of rehabilitation is to prevent complications, minimize impairments, and maximize function". The topics of intensity and timing of intervention are widely debated across various fields. Results are contradictory: some studies indicate better outcomes with early intervention, while other studies indicate starting therapy too early may be detrimental to the patient's recovery. Recent research suggests, that therapy be functional and focus on communication goals that are appropriate for the patient's individual lifestyle. Specific treatment considerations for working with individuals with Wernicke's aphasia (or those who  exhibit deficits in auditory comprehension) include using familiar materials, using shorter and slower utterances when speaking, giving direct instructions, and using repetition as needed. Role of neuroplasticity in recovery. Neuroplasticity is defined as the brain's ability to reorganize itself, lay new pathways, and rearrange existing ones, as a result of experience. Neuronal changes after damage to the brain such as collateral sprouting, increased activation of the homologous areas, and map extension demonstrate the brain's neuroplastic abilities. According to Thomson, "Portions of the right hemisphere, extended left brain sites, or both have been shown to be recruited to perform  language functions after brain damage. All of the neuronal changes recruit areas not originally or directly responsible for large portions of linguistic processing. Principles of neuroplasticity have been proven effective in neurorehabilitation after damage to the brain. These principles include: incorporating multiple modalities into treatment to create stronger neural connections, using stimuli that evoke positive emotion, linking concepts with simultaneous and related presentations, and finding the appropriate intensity and duration of treatment for each individual patient. Auditory comprehension treatment. Auditory comprehension is a primary focus in treatment for Wernicke's aphasia, as it is the main deficit related to this  diagnosis. Therapy activities may include: Word retrieval. Anomia is consistently seen in aphasia, so many treatment techniques aim to help patients with word finding problems. One example of a semantic approach is referred to as semantic feature analyses. The process includes naming the target object shown in the picture and producing words that are semantically related to the target. Through production of semantically similar features, participants develop more skilled in naming stimuli due to the increase in lexical activation. Restorative therapy approach. Neuroplasticity is a central component to restorative therapy to compensate for brain damage. This approach is especially useful  in Wernicke's aphasia patients that have had a stroke to the left brain hemisphere. "Schuell's stimulation approach" is a main method in traditional aphasia therapy that follows principles to retrieve function in the auditory modality of language and influence surrounding regions through stimulation. The guidelines to have the most effective stimulation are as follows: Auditory stimulation of language should be intensive and always present when other language modalities are stimulated. Schuell's stimulation utilizes stimulation through therapy tasks beginning at a simplified task and progressing to become more difficult including: Social approach to treatment. The social approach involves  a collaborative effort on behalf of patients and clinicians to determine goals and outcomes for therapy that could improve the patient's quality of life. A conversational approach is thought to provide opportunities for development and the use of strategies to overcome barriers to communication. The main goals of this treatment method are to improve the patient's conversational confidence and skills in natural contexts using conversational coaching, supported conversations, and partner training. Additionally, it is important to include the families of patients with aphasia in treatment programs. Clinicians can teach family members how to support one another, and how  to adjust their speaking patterns to facilitate their loved one's treatment and rehabilitation. Prognosis. Prognosis is strongly dependent on the location and extent of the lesion (damage) to the brain. Many personal factors also influence how a person will recover, which include age, previous medical history, level of education, gender, and motivation. All of these factors influence the brain's ability to adapt to change, restore previous skills, and learn new skills. It is important to remember that all the presentations of Receptive Aphasia may vary. The presentation of symptoms and prognosis are both dependent on personal components related  to the individual's neural organization before the stroke, the extent of the damage, and the influence of environmental and behavioral factors after the damage occurs. The quicker a diagnosis of a stroke is made by a medical team, the more positive the patient's recovery may be. A medical team will work to control the signs and symptoms of the stroke and rehabilitation therapy will begin to manage and recover lost skills. The rehabilitation team may consist of a certified speech-language pathologist, physical therapist, occupational therapist, and the family or caregivers. The length of therapy will be different  for everyone, but research suggests that intense therapy over a short amount of time can improve outcomes of speech and language therapy for patients with aphasia. Research is not suggesting the only way therapy should be administered, but gives insight on how therapy affects the patient's prognosis.