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Deep Learning Technology: Sebastian Arnold, Betty van Aken, Paul Grundmann, Felix A. Gers and Alexander Löser. Learning Contextualized Document Representations for Healthcare Answer Retrieval. The Web Conference 2020 (WWW'20)
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Using verbal descriptions may be helpful for individuals with certain types of agnosia. Individuals such as prosopagnosics may find it useful to listen to a description of their friend or family member and recognize them based on this description more easily than through visual cues.
Alternate cues may be particularly useful to an individual with environmental agnosia or prosopagnosia. Alternate cues for an individual with environmental agnosia may include color cues or tactile markers to symbolize a new room or to remember an area by. Prosopagnosics may use alternate cues such as a scar on an individual's face or crooked teeth in order to recognize the individual. Hair color and length can be helpful cues as well.
One treatment thought to be effective is the repeated exposure to a particular face or object, where impaired perception may be reorganized in memory, leading to improvement on tests of imagery relative to tests of perception. The key factor for this type of treatment to be successful is a regular and consistent exposure, which will lead to improvements in the long run. Results may not be seen right away, but are eventually possible.
The best way to see if anomic aphasia has developed is by using verbal as well as imaging tests. The combination of the two tests seem to be most effective, since either test done alone may give false positives or false negatives. For example, the verbal test is used to see if there is a speech disorder, and whether it is a problem in speech production or in comprehension. Patients with Alzheimer's disease have speech problems that are linked to dementia or progressive aphasias which can include anomia. The imaging test, mostly done using MRI scans, is ideal for lesion mapping or viewing deterioration in the brain. However, imaging cannot diagnose anomia on its own because the lesions may not be located deep enough to damage the white matter or damage the arcuate fasciculus. However, anomic aphasia is very difficult to associate with a specific lesion location in the brain. Therefore, the combination of speech tests and imaging tests has the highest sensitivity and specificity.
It is important to first do a hearing test, in case the patient cannot clearly hear the words or sentences needed in the speech repetition test. In the speech tests, the person is asked to repeat a sentence with common words; if the person cannot identify the word but he or she can describe it, then the person is highly likely to have anomic aphasia. However, to be completely sure, the test is given while a test subject is in an fMRI scanner, and the exact location of the lesions and areas activated by speech are pinpointed. Few simpler or cheaper options are available, so lesion mapping and speech repetition tests are the main ways of diagnosing anomic aphasia.
There are few neuropsychological assessments that can definitively diagnose prosopagnosia. One commonly used test is the famous faces tests, where individuals are asked to recognize the faces of famous persons. However, this test is difficult to standardize. The Benton Facial Recognition Test (BFRT) is another test used by neuropsychologists to assess face recognition skills. Individuals are presented with a target face above six test faces and are asked to identify which test face matches the target face. The images are cropped to eliminate hair and clothes, as many people with prosopagnosia use hair and clothing cues to recognize faces. Both male and female faces are used during the test. For the first six items only one test face matches the target face; during the next seven items, three of the test faces match the target faces and the poses are different. The reliability of the BFRT was questioned when a study conducted by Duchaine and Nakayama showed that the average score for 11 self-reported prosopagnosics was within the normal range.
The test may be useful for identifying patients with apperceptive prosopagnosia, since this is mainly a matching test and they are unable to recognize both familiar and unfamiliar faces. They would be unable to pass the test. It would not be useful in diagnosing patients with associative prosopagnosia since they are able to match faces.
The Cambridge Face Memory Test (CFMT) was developed by Duchaine and Nakayama to better diagnose people with prosopagnosia. This test initially presents individuals with three images each of six different target faces. They are then presented with many three-image series, which contain one image of a target face and two distracters. Duchaine and Nakayama showed that the CFMT is more accurate and efficient than previous tests in diagnosing patients with prosopagnosia. Their study compared the two tests and 75% of patients were diagnosed by the CFMT, while only 25% of patients were diagnosed by the BFRT. However, similar to the BFRT, patients are being asked to essentially match unfamiliar faces, as they are seen only briefly at the start of the test. The test is not currently widely used and will need further testing before it can be considered reliable.
The 20-item Prosopagnosia Index (PI20) is a freely available and validated self-report questionnaire that is able to identify individuals with prosopagnosia. It has been validated against the famous faces test and Cambridge Face Memory Test, with evidence that PI20 scores are correlated with performance on these objective measures of face recognition. It can be downloaded from the Royal Society's Open Science website and on . Alternatively, the questionnaire can be completed online on the official website.
Cases with integrative agnosia appear to have medial ventral lesions in the extrastriate cortex. Those who have integrative agnosia are better able to identify inanimate than animate items, which indicates processes that lead to accurate perceptual organization of visual information can be impaired. This is attributed to the importance of perceptual updating of stored visual knowledge, which is particularly important for classes of stimuli that have many perceptual neighbors and/or stimuli for which perceptual features are central to their stored representations. Patients also show a tendency to process visual stimuli initially at a global rather than local level. Although the grouping of local elements into perceptual wholes can be impaired, patients can remain sensitive to holistic visual representations.
When determining whether a patient has form agnosia or integrative agnosia, an Efron shape test can be performed. A poor score on the Efron shape test will indicate form agnosia, as opposed to integrative agnosia. A good score on the Efron shape test, but a poor score on a figure-ground segmentation test and an overlapping figures test will indicate integrative agnosia. A patient with integrative agnosia will find it hard to group and segment shapes, especially if there are overlapping animate items or they can over segment objects with high internal detail. However, the patient should have and understand basic coding of shape.
Sensory aphasia cannot be diagnosed through the use of imaging techniques. Differences in cognition between asymptomatic subjects and affected patients can be observed via functional magnetic resonance imaging (fMRI). However, these results only reveal temporal differences in cognition between control and diagnosed subjects. The degree of progression during therapy can also be surveyed through cognition tests monitored by fMRI. Many patients’ progress is assessed over time via repeated testing and corresponding cerebral imaging by fMRI.
Specialists, like ophthalmologists or audiologists, can test for perceptual abilities. Detailed testing is conducted, using specially formulated assessment materials, and referrals to neurological specialists is recommended to support a diagnosis via brain imaging or recording techniques. The separate stages of information processing in the object recognition model are often used to localize the processing level of the deficit.
Testing usually consists of object identification and perception tasks including:
- object-naming tasks
- object categorization or figure matching
- drawing or copying real objects or images or illustrations
- unusual views tests
- overlapping line drawings
- partially degraded or fragmented image identification
- face or feature analysis
- fine line judgment
- figure contour tracking
- visual object description
- object-function miming
- tactile ability tests (naming by touch)
- auditory presentation identification
Sensory modality testing allows practitioners to assess for generalized versus specific deficits, distinguishing visual agnosias from optic aphasia, which is a more generalized deficit in semantic knowledge for objects that spans multiple sensory modalities, indicating an impairment in the semantic representations themselves.
Sensory aphasia is typically diagnosed by non-invasive evaluations. Neurologists, neuropsychologists or speech pathologists will administer oral evaluations to determine the extent of a patient’s comprehension and speech capability. Initial assessment will determine if the cause of linguistic deficiency is aphasia. If the diagnosis is then confirmed, testing will next address the type of aphasia and its severity. The Boston Diagnostic Aphasia Examination specializes in determining the severity of a sensory aphasia through the observation of conversational behaviors. Several modalities of perception and response are observed in conjunction with the subject’s ability to process sensory information. The location of the brain lesion and type of the aphasia can then be inferred from the observed symptoms. The Minnesota Test for Differential Diagnosis is the most lengthy and thorough assessment of sensory aphasia. It pinpoints weaknesses in the auditory and visual senses, as well as reading comprehension. From this differential diagnosis, a patient’s course of treatment can be determined. After treatment planning, the Porch Index of Communicative Ability is used to evaluate prognosis and the degree of recovery.
The nature of the alleged mental representations that underlie the act of pointing to target body parts have been a controversial issue. Originally, it was diagnosed as the effects of general mental deterioration or of aphasia on the task of pointing to body parts on verbal command. However, contemporary neuropsychological therapy seeks to establish the independence of autotopagnosia from other disorders. With such a general definition, a patient that presents with a dysfunction of or failure in accessing one of four mental representation systems suffers from autotopagnosia. Through observational testing, the type of mental misrepresentation of the body can be deduced: whether "semantic", "visuospatial", "somatosensory", or "motor misrepresentations". Neuropsychological tests can provide a proper diagnosis in regards to the specificity of patient’s agnosic condition.
1) Test 1: Body Part Localization: Free vision and no vision conditions
2) Test 2: On-line positioning of body vis-à-vis objects
3) Test 3: Localization of objects on the body surface
4) Test 4: Body part semantic knowledge
5) Test 5: Matching body parts: Effect of viewing angle
Management strategies for acquired prosopagnosia, such as a person who has difficulty recognizing people's faces after a stroke, generally have a low rate of success. Acquired prosopagnosia sometimes spontaneously resolves on its own.
Someone with jargon aphasia may exhibit the following behaviors[4]:
- Intermixing real words and nonsensical words while speaking or writing
- Failing to recognize mistakes being made while speaking or writing
- Using real words in incorrect situations
- Frequent, repetitive uttering of low frequency words
- The inability to say or write a specific word or phrase
Some of the specific types of language errors that occur are[5]:
Lexical (real word):
Semantic - Real word that was semantically related to target. ("dog" instead of "cat")
Formal - Real word that shared either the initial phoneme or at least 50% of phonemes with target. ("dog" instead of "desk" or "dog" instead of "frog")
Mixed - Real word that was both semantically and phonologically related to target. ("bicycle" instead of "motorcycle")
Visual - Real word of an item similar in visual form to the target. ("ball" instead of "orange")
Unrelated - Real word that was not related to the target in any obvious way. ("dog" instead of "apple")
Non-lexical (nonword):
Phonological - Nonword that shared either the initial phoneme or at least 50% of phonemes with target. ("deg" instead of "dog")
Neologistic - Nonword not reaching the criterion for phonological relatedness (i.e., sharing less than 50% of phonemes with the target and with a different initial phoneme). Nonwords that are pseudo compound words. ("kib" instead of "dog")
Other Errors:
Don’t know - Indication that response was unknown or if item was not responded to at all. ("I don’t know" or silence)
Description - Attempts to describe as opposed to name item. (Multiple word responses)
Jargon aphasia must be diagnosed through a series of tests. Since the number of individuals that have aphasia after suffering a stroke is high, a test is usually carried out soon after the stroke occurs. There is a list of basic exercises to help assess a person’s language skills, such as:
- Naming objects that begin with a certain letter
- Reading or writing
- Holding a conversation
- Understanding directions and commands
There is also a common test used, called the Boston Diagnostic Aphasia Examination test, which incorporates exercises that extensively review the person’s language skills[2].
Following are some precautions that should be taken to avoid aphasia, by decreasing the risk of stroke, the main cause of aphasia:
- Exercising regularly
- Eating a healthy diet
- Keeping alcohol consumption low and avoiding tobacco use
- Controlling blood pressure
As autotopagnosia is not a life-threatening condition it is not on the forefront of medical research. Rather, more research is conducted regarding treatments and therapies to alleviate the lesions and traumas that can cause autotopagnosia. Of all the agnosias, visual agnosia is the most common subject of investigation because it is easiest to assess and has the most promise for potential treatments. Most autotopagnosia studies are centered on a few test subjects as part of a group of unaffected or “controlled” participants, or a simple case study. Case studies surrounding a single patient are most common due to the vague nature of the disease.
When addressing Wernicke’s aphasia, according to Bakheit et al. (2007), the lack of awareness of the language impairments, a common characteristic of Wernicke’s aphasia, may impact the rate and extent of therapy outcomes. Klebic et al. (2011) suggests that people benefit from continuing therapy upon discharge from the hospital to ensure generalization. Robey (1998) determined that at least 2 hours of treatment per week is recommended for making significant language gains. Spontaneous recovery may cause some language gains, but without speech-language therapy, the outcomes can be half as strong as those with therapy.
When addressing Broca’s aphasia, better outcomes occur when the person participates in therapy, and treatment is more effective than no treatment for people in the acute period. Two or more hours of therapy per week in acute and post-acute stages produced the greatest results. High intensity therapy was most effective, and low intensity therapy was almost equivalent to no therapy.
People with global aphasia are sometimes referred to as having irreversible aphasic syndrome, often making limited gains in auditory comprehension, and recovering no functional language modality with therapy. With this said, people with global aphasia may retain gestural communication skills that may enable success when communicating with conversational partners within familiar conditions. Process-oriented treatment options are limited, and people may not become competent language users as readers, listeners, writers, or speakers no matter how extensive therapy is. However, people’s daily routines and quality of life can be enhanced with reasonable and modest goals. After the first month, there is limited to no healing to language abilities of most people. There is a grim prognosis leaving 83% who were globally aphasic after the first month they will remain globally aphasic at the first year. Some people are so severely impaired that their existing process-oriented treatment approaches offer signs of progress, and therefore cannot justify the cost of therapy.
Perhaps due to the relative rareness of conduction aphasia, few studies have specifically studied the effectiveness of therapy for people with this type of aphasia. From the studies performed, results showed that therapy can help to improve specific language outcomes. One intervention that has had positive results is auditory repetition training. Kohn et al. (1990) reported that drilled auditory repetition training related to improvements in spontaneous speech, Francis et al. (2003) reported improvements in sentence comprehension, and Kalinyak-Fliszar et al. (2011) reported improvements in auditory-visual short-term memory.
Most acute cases of aphasia recover some or most skills by working with a speech-language pathologist. Recovery and improvement can continue for years after the stroke. After the onset of Aphasia, there is approximately a six-month period of spontaneous recovery; during this time, the brain is attempting to recover and repair the damaged neurons. Improvement varies widely, depending on the aphasia's cause, type, and severity. Recovery also depends on the person's age, health, motivation, handedness, and educational level.
There is no one treatment proven to be effective for all types of aphasias. The reason that there is no universal treatment for aphasia is because of the nature of the disorder and the various ways it is presented, as explained in the above sections. Aphasia is rarely exhibited identically, implying that treatment needs to be catered specifically to the individual. Studies have shown that, although there is no consistency on treatment methodology in literature, there is a strong indication that treatment in general has positive outcomes. Therapy for aphasia ranges from increasing functional communication to improving speech accuracy, depending on the person's severity, needs and support of family and friends. Group therapy allows individuals to work on their pragmatic and communication skills with other individuals with aphasia, which are skills that may not often be addressed in individual one-on-one therapy sessions. It can also help increase confidence and social skills in a comfortable setting.
Evidence dose not support the use of transcranial direct current stimulation (tDCS) for improving aphasia after stroke.
Specific treatment techniques include the following:
- Copy and Recall Therapy (CART) - repetition and recall of targeted words within therapy may strengthen orthographic representations and improve single word reading, writing, and naming
- Visual Communication Therapy (VIC) - the use of index cards with symbols to represent various components of speech
- Visual Action Therapy (VAT) - typically treats individuals with global aphasia to train the use of hand gestures for specific items
- Functional Communication Treatment (FCT) - focuses on improving activities specific to functional tasks, social interaction, and self-expression
- Promoting Aphasic's Communicative Effectiveness (PACE) - a means of encouraging normal interaction between people with aphasia and clinicians. In this kind of therapy the focus is on pragmatic communication rather than treatment itself. People are asked to communicate a given message to their therapists by means of drawing, making hand gestures or even pointing to an object
- Melodic Intonation Therapy (MIT) - aims to use the intact melodic/prosodic processing skills of the right hemisphere to help cue retrieval of words and expressive language
- Other - i.e. drawing as a way of communicating, trained conversation partners
Semantic feature analysis (SFA) -a type of aphasia treatment that targets word-finding deficits. It is based on the theory that neural connections can strengthened by using using related words and phrases that are similar to the target word, to eventually activate the target word in the brain. SFA can be implemented in multiple forms such as verbally, written, using picture cards, etc. The SLP provides prompting questions to the individual with aphasia in order for the person to name the picture provided. Studies show that SFA is an effective intervention for improving confrontational naming.
Melodic intonation therapy is used to treat non-fluent aphasia and has proved to be effective in some cases. However, there is still no evidence from randomized controlled trials confirming the efficacy of MIT in chronic aphasia. MIT is used to help people with aphasia vocalize themselves through speech song, which is then transferred as a spoken word. Good candidates for this therapy include people who have had left hemisphere strokes, non-fluent aphasias such as Broca's, good auditory comprehension, poor repetition and articulation, and good emotional stability and memory. An alternative explanation is that the efficacy of MIT depends on neural circuits involved in the processing of rhythmicity and formulaic expressions (examples taken from the MIT manual: “I am fine,” “how are you?” or “thank you”); while rhythmic features associated with melodic intonation may engage primarily left-hemisphere subcortical areas of the brain, the use of formulaic expressions is known to be supported by right-hemisphere cortical and bilateral subcortical neural networks.
According to the National Institute on Deafness and Other Communication Disorders (NIDCD), involving family with the treatment of an Aphasic loved one is ideal for all involved, because while it will no doubt assist in their recovery, it will also make it easier for members of the family to learn how best to communicate with them.
There is no method available to completely cure anomic aphasia. However, there are treatments to help improve word-finding skills.
Although a person with anomia may find it difficult to recall many types of words such as common nouns, proper nouns, verbs, etc., many studies have shown that treatment for object words, or nouns, has shown promise in rehabilitation research. The treatment includes visual aids, such as pictures, and the patient is asked to identify the object or activity. However, if that is not possible, then the patient is shown the same picture surrounded by words associated with the object or activity. Throughout the process, positive encouragement is provided. The treatment shows an increase in word-finding during treatment; however, word identifying decreased two weeks after the rehabilitation period. Therefore, it shows that rehabilitation effort needs to be continuous for word-finding abilities to improve from the baseline. The studies show that verbs are harder to recall or repeat, even with rehabilitation.
Other methods in treating anomic aphasia include Circumlocution Induced Naming therapy (CIN), wherein the patient uses circumlocution to assist with his or her naming rather than just being told to name the item pictured after given some sort of cue. Results suggest that the patient does better in properly naming objects when undergoing this therapy because CIN strengthens the weakened link between semantics and phonology for patients with anomia, since they often know what an object is used for but cannot verbally name it.
Anomia is often burdensome on the families and friends of those suffering from it. One way to overcome this burden is computer-based treatment models, effective especially when used with clinical therapy. Leemann et al. provided anomic patients with computerized-assisted therapy (CAT) sessions, along with traditional therapy sessions using treatment lists of words. Some of the patients received a drug known to help relieve symptoms of anomia (levodopa) while others received a placebo. The researchers found that the drug had no significant effects on improvement with the treatment lists, but almost all of the patients improved after the CAT sessions. They concluded that this form of computerized treatment is effective in increasing naming abilities in anomic patients.
Additionally, one study researched the effects of using "excitatory (anodal) transcranial direct current stimulation" over the right temporo-parietal cortex, a brain area that seems to correlate to language. The electrical stimulation seemed to enhance language training outcome in patients with chronic aphasia.
The only way to treat aphasia is with speech and language therapy (SLT). It will not completely restore the person’s prior level of communication, but SLT can lead to a massive improvement of jargon aphasia. Recipients of this treatment typically achieve better use of residual language abilities, improved language skills, and the ability to communicate in a different way by making up for missing words in their speech[2].
One specific method that has shown to lead to improvements with certain symptoms is “phonological component analysis”, or PCA for short. Participants in PCA therapy tend to improve in the ability to name specific items that they are test on, as well as the decrease in use of nonwords to describe said items. Seeing promising results from this type of therapy has led to much optimism in hopes of developing more treatment methods for jargon aphasia[6].
If a suspected brain injury has occurred, the patient undergoes a series of medical imaging, which could include MRI(magnetic resonance imaging) or CT (computed tomography) scan. After the diagnosis of a brain injury, a speech and language pathologist will perform a variety of tests to determine the classification of aphasia. Additionally, the Boston Assessment of Severe Aphasia (BASA) is a commonly used assessment for diagnosing aphasia. BASA is used to determine treatment plans after strokes lead to symptoms of aphasia and tests both gestural and verbal responses. Cognitive functions can be assessed using the Cognitive Test Battery for Global Aphasia (CoBaGa). The CoBaGa is an appropriate measure to assess a person with severe aphasia because it does not require verbal responses, rather manipulative answers. The CoBaGa assesses cognitive functions such as attention, executive functions, logical reasoning, memory, visual-auditory recognition, and visual-spatial ability. Van Mourik et al. conducted a study in which they assessed the cognitive abilities of people with global aphasia using the Global Aphasic Neuropsychological Battery. This test assesses attention/concentration, memory, intelligence, and visual and auditory nonverbal recognition. The results of this study helped the researchers determine there were varying levels of severity among individuals with global aphasia.
Sign language therapy has been identified as one of the top five most common treatments for auditory verbal agnosia. This type of therapy is most useful because, unlike other treatment methods, it does not rely on fixing the damaged areas of the brain. This is particularly important with AVA cases because it has been so hard to identify the causes of the agnosia in the first place, much less treat those areas directly. Sign language therapy, then, allows the person to cope and work around the disability, much in the same way it helps deaf people. In the beginning of therapy, most will work on identifying key objects and establishing an initial core vocabulary of signs. After this, the patient graduates to expand the vocabulary to intangible items or items that are not in view or present. Later, the patient learns single signs and then sentences consisting of two or more signs. In different cases, the sentences are first written down and then the patient is asked to sign them and speak them simultaneously. Because different AVA patients vary in the level of speech or comprehension they have, sign language therapy learning order and techniques are very specific to the individual's needs.
Visual agnosia is an impairment in recognition of visually presented objects. It is not due to a deficit in vision (acuity, visual field, and scanning), language, memory, or low intellect. While cortical blindness results from lesions to primary visual cortex, visual agnosia is often due to damage to more anterior cortex such as the posterior occipital and/or temporal lobe(s) in the brain. There are two types of visual agnosia: apperceptive agnosia and associative agnosia.
Recognition of visual objects occurs at two primary levels. At an apperceptive level, the features of the visual information from the retina are put together to form a perceptual representation of an object. At an associative level, the meaning of an object is attached to the perceptual representation and the object is identified. If a person is unable to recognize objects because they cannot perceive correct forms of the objects, although their knowledge of the objects is intact (i.e. they do not have anomia), they have apperceptive agnosia. If a person correctly perceives the forms and has knowledge of the objects, but cannot identify the objects, they have associative agnosia.
Broadly, visual agnosia is divided into apperceptive and associative visual agnosia.
Apperceptive agnosia is failure of object recognition even when the basic visual functions (acuity, color, motion) and other mental processing, such as language and intelligence, are normal. The brain must correctly integrate features such as edges, light intensity, and color from sensory information to form a complete percept of an object. If a failure occurs during this process, a percept of an object is not fully formed and thus it cannot be recognized. Tasks requiring copying, matching, or drawing simple figures can distinguish the individuals with apperceptive agnosia because they cannot perform such tasks.
Associative agnosia is an inability to identify objects even with apparent perception and knowledge of them. It involves a higher level of processing than apperceptive agnosia. Individuals with associative agnosia can copy or match simple figures, indicating that they can perceive objects correctly. They also display the knowledge of objects when tested with tactile or verbal information. However, when tested visually, they cannot name or describe common objects. This means that there is an impairment in associating the perception of objects with the stored knowledge of them.
Although visual agnosia can be general, there exist many variants that impair recognition of specific types. These variants of visual agnosia include prosopagnosia (inability to recognize faces), pure word blindness (inability to recognize words, often called "agnosic alexia" or "pure alexia"), agnosias for colors (inability to differentiate colors), agnosias for the environment (inability to recognize landmarks or difficult with spatial layout of an environment, i.e. topographagnosia) and simultanagosia (inability to sort out multiple objects in a visual scene).
Speech and language therapy is typically the primary treatment for individuals with aphasia. The goal of speech and language therapy is to increase the person’s communication abilities to a level functional for daily life. Goals are chosen based on collaboration between speech language pathologists, patients, and their family/caregivers. Goals should be individualized based on the person’s aphasia symptoms and communicative needs. In 2016, Wallace et al. found the following outcomes were commonly prioritized in therapy: communication, life participation, physical and emotional well-being, normalcy, and health and support services. However, available research is inconclusive about which specific approach to speech and language therapy is most effective in treating global aphasia.
Therapy can be either group or individual. Group therapies that integrate the use of visual aids allow for enhanced social and communication-skill development. Group therapy sessions typically revolve around simple, preplanned activities or games, and aim to facilitate social communication.
One particular therapy designed specifically for treatment of aphasia is Visual Action Therapy (VAT). VAT is a non-verbal gestural output program with 3 phases and 30 total steps. The program teaches unilateral gestures as symbolic representations of real life objects. Research on the effectiveness of VAT is limited and inconclusive.
One important therapy technique includes teaching family members and caregivers strategies for more effectively communicating with their loved ones. Research offers such strategies including, simplifying sentences and using common words, gaining the person's attention before speaking, using pointing and visual cues, allowing for adequate response time, and creating a quiet environment free of distractions.
Another approach to speech and language treatment is constraint-induced language therapy (CILT). CILT involves teaching the patient to use speech in small segments but avoid using gestures and familiar words . The speech language pathologist provides positive feedback throughout and ignores any mistakes made by the patient. The intensity with which this treatment is provided has been debated in the literature. One study, performed in 2015, compared the outcomes of patients with aphasia who received CILT for either 30 hours total over 2 weeks or 30 hours distributed over 10 weeks. Results showed that both groups made significant speech and language improvements. Overall, CILT is an effective treatment at a variety of intensities.
Research supporting the efficacy of pharmacological treatments for aphasia is limited. To date, no large scale clinical trials have proven benefits of pharmacological treatment.
Apperceptive agnosia is a failure in recognition that is due to a failure of perception. In contrast, associative agnosia is a type of agnosia where perception occurs but recognition still does not occur. When referring to apperceptive agnosia, visual and object agnosia are most commonly discussed; This occurs because apperceptive agnosia is most likely to present visual impairments. However, in addition to visual apperceptive agnosia there are also cases of apperceptive agnosia in other sensory areas.
Treating auditory verbal agnosia with intravenous immunoglobulin (IVIG) is controversial because of its inconsistency as a treatment method. Although IVIG is normally used to treat immune diseases, some individuals with auditory verbal agnosia have responded positively to the use of IVIG. Additionally, patients are more likely to relapse when treated with IVIG than other pharmacological treatments. IVIG is, thus, a controversial treatment as its efficacy in treating auditory verbal agnosia is dependent upon each individual and varies from case to case.