Made by DATEXIS (Data Science and Text-based Information Systems) at Beuth University of Applied Sciences Berlin
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)
Funded by The Federal Ministry for Economic Affairs and Energy; Grant: 01MD19013D, Smart-MD Project, Digital Technologies
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.
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.
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.
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.
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.
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.
Agraphia cannot be directly treated, but individuals can be rehabilitated to regain some of their previous writing abilities.
For the management of phonological agraphia, individuals are trained to memorize key words, such as a familiar name or object, that can then help them form the grapheme for that phoneme. Management of allographic agraphia can be as simple as having alphabet cards so the individual can write legibly by copying the correct letter shapes. There are few rehabilitation methods for apraxic agraphia; if the individual has considerably better hand control and movement with typing than they do with handwriting, then they can use technological devices. Texting and typing do not require the same technical movements that handwriting does; for these technological methods, only spatial location of the fingers to type is required. If copying skills are preserved in an individual with apraxic agraphia, repeated copying may help shift from the highly intentional and monitored hand movements indicative of apraxic agraphia to a more automated control.
Micrographia is a condition that can occur with the development of other disorders, such as Parkinson's disease, and is when handwriting becomes illegible because of small writing. For some individuals, a simple command to write bigger eliminates the issue.
- Anagram and Copy Treatment (ACT) uses the arrangement of component letters of target words and then repeated copying of the target word. This is similar to the CART; the main difference is that the target words for ACT are specific to the individual. Target words that are important in the life of the individual are emphasized because people with deep or global agraphias do not typically have the same memory for the words as other people with agraphia may. Writing can be even more important to these people as it can cue spoken language. ACT helps in this by facilitating the relearning of a set of personally relevant written words for use in communication.
- Copy and Recall Treatment (CART) method helps to reestablish the ability to spell specific words that are learned through repeated copying and recall of target words. CART is more likely to be successful in treating lexical agraphia when a few words are trained to mastery than when a large group of unrelated words is trained. Words chosen can be individualized to the patient, which makes treatment more personalized.
- Graphemic buffer uses the training of specific words to improve spelling. Cueing hierarchies and copy and recall method of specific words are used, to work the words into the short-term memory loop, or graphemic buffer. The segmentation of longer words into shorter syllables helps bring words into short-term memory.
- Problem solving approach is used as a self-correcting method for phonological errors. The individual sounds out the word and attempts to spell it, typically using an electronic dictionary-type device that indicates correct spelling. This method takes advantage of the preserved sound-to-letter correspondences when they are intact. This approach may improve access to spelling memory, strengthen orthographic representations, or both.
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.
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.
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).
Topographical disorientation is usually diagnosed with the use of a comprehensive battery of neuropsychological tests combined with a variety of orientation tasks performed by the participants in both virtual and real surroundings. Performance on certain tests can identify underlying neurological disorders and verify the disorientation as a selective impairment. Brain imaging is used to determine regions of brain damage, if any. Navigational skills can be assessed by tests pertaining to memory, visual-perceptual abilities, object recognition, mental rotation, imagery abilities, and spatial abilities. More direct testing of navigation involves asking the patient to describe a route, read a map, draw a map, follow a route, or point out landmarks.
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.
Auditory agnosia is a form of agnosia that manifests itself primarily in the inability to recognize or differentiate between sounds. It is not a defect of the ear or "hearing", but a neurological inability of the brain to process sound meaning. It is a disruption of the "what" pathway in the brain. Persons with auditory agnosia can physically hear the sounds and describe them using unrelated terms, but are unable to recognize them. They might describe the sound of some environmental sounds, such as a motor starting, as resembling a lion roaring, but would not be able to associate the sound with "car" or "engine", nor would they say that it "was" a lion creating the noise. Auditory agnosia is caused by damage to the secondary and tertiary auditory cortex of the temporal lobe of the brain.
There are three primary distinctions of auditory agnosia that fall into two categories.
Ideational apraxia is a difficult disorder to diagnose. That is because the majority of individuals who have this disorder almost always have some other type of dysfunction such as agnosia or aphasia. The tests used to make an IA diagnosis can range from easy single object tasks to complex multiple object tasks. When being tested a patient may be asked to view twenty objects. They then have to demonstrate the use of each single object following three different ways of presenting the stimuli. The patient must then perform complex test where the examiner describes a task such as making coffee and the patient must show the sequential steps that makes a cup of coffee. The patients are then scored on how many errors are seen by the examiner. The errors of the patients in performing the MOT were scored according to a set of criteria partly derived from De Renzi and Lucchelli.
Assessment will usually include an interview with the child’s caregiver, observation of the child in an unstructured setting, a hearing test, and standardized tests of language and nonverbal ability. There is a wide range of language assessments in English. Some are restricted for use by speech and language professionals (therapists or SALTs in the UK, speech-language pathologists, SLPs, in the US and Australia).
A commonly used test battery for diagnosis of SLI is the Clinical Evaluation of Language Fundamentals (CELF).
Assessments that can be completed by a parent or teacher can be useful to identify children who may require more in-depth evaluation.
The Grammar and Phonology Screening (GAPS) test is a quick (ten minute) simple and accurate screening test developed and standardized in the UK. It is suitable for children from 3;4 to 6;8 years;months and can be administered by professionals and non-professionals (including parents) alike, and has been demonstrated to be highly accurate (98% accuracy) in identifying impaired children who need specialist help vs non-impaired children. This makes it potentially a feasible test for widespread screening.
The Children’s Communication Checklist (CCC–2) is a parent questionnaire suitable for testing language skills in school-aged children.
Informal assessments, such as language samples, may also be used. This procedure is useful when the normative sample of a given test is inappropriate for a given child, for instance, if the child is bilingual and the sample was of monolingual children. It is also an ecologically valid measure of all aspects of language (e.g. semantics, syntax, pragmatics, etc.).
To complete a language sample, the SLP will spend about 15 minutes talking with the child. The sample may be of a conversation (Hadley, 1998), or narrative retell. In a narrative language sample, the SLP will tell the child a story using a wordless picture book (e.g. "Frog Where Are You?", Mayer, 1969), then ask the child to use the pictures and tell the story back.
Language samples are typically transcribed using computer software such as the Systematic Analysis of Language Software (SALT, Miller et al. 2012), and then analyzed. For example, the SLP might look for whether the child introduces characters to their story or jumps right in, whether the events follow a logical order, and whether the narrative includes a main idea or theme and supporting details.
Phonagnosia (from Ancient Greek φωνή "phone", "voice" and γνῶσις "gnosis", "knowledge") is a type of agnosia, or loss of knowledge, that involves a disturbance in the recognition of familiar voices and the impairment of voice discrimination abilities in which the affected individual does not suffer from comprehension deficits. Phonagnosia is an auditory agnosia, an acquired auditory processing disorder resulting from brain damage, other auditory agnosias include cortical deafness and auditory verbal agnosia also known as pure word deafness.
Since people suffering from phonagnosia do not suffer from aphasia, it is suggested that the structures of linguistic comprehension are functionally separate from those of the perception of the identity of the speaker who produced it.
Phonagnosia is the auditory equivalent of prosopagnosia. Unlike Prosopagnosia, investigations of phonagnosia have not been extensively pursued. Phonagnosia was first described by a study by Van Lancker and Cantor in 1982. The subjects in this study were asked to identify which of four names or faces matched a specific famous voice. The subjects could not complete the task. Since then, there have been a couple studies done on patients with phonagnosia. The clinical and radiologic findings with computerized tomographic scans cat scan in these cases suggest that recognition of familiar voices is impaired by damage to the inferior and parietal regions of the right hemisphere while voice discrimination is impaired by temporal lobe damage of either hemisphere. These studies have also shown evidence for a double dissociation between voice recognition and voice discrimination. Some patients will perform normally on the discrimination tasks but poorly on the recognition tasks; whereas the other patients will perform normally on the recognition tasks but poorly on the discrimination tasks. Patients did not perform poorly on both tasks.
Associative phonagnosia is a form of phonagnosia that develops with dementia or other focal neurodegenerative disorders. Some research has led to questions of other impairments in phonagnosics. Recently, studies have shown that phonagnosics also have trouble in recognizing the sounds of familiar instruments. As it is with voices, they also show deficiency in distinguishing between sounds from different instruments. Although the disability is shown, phonagnosics are much less affected in this area of sound discrimination. In distinguishing voices, it is a complete agnosia, but this is not the case for musical instrument sounds, as they can correctly identify some of them. Controversy arises in that not all phonagnosics exhibit these symptoms, and so not all researchers agree that it should be attributed to the damage suffered that causes phonagnosia. Much debate has arisen over the fact that it seems that separate areas of the brain are utilized to handle information from language and music. This has led some researchers to skeptically consider this impairment as a clear symptom of the disorder. Again, more research is needed to create a clearer conclusion.
An interesting attribute that phonagnosics possess is that they can correctly detect emotions in voices when someone talks to them. They can also correctly match an emotion with a facial expression. Although surprising, this finding is sensible because it is known and well agreed upon that the limbic system, involved in expressing emotions and detecting emotions of others, is a separate system within the brain. The limbic system is made up of several brain structures including the hippocampus, amygdala, anterior thalamic nuclei, septum, limbic cortex and fornix.
Presently, there is no therapy or treatment for phonagnosia. Clearly, more research is needed to accomplish the feat of developing treatment for the disorder. The lack of treatment stems from the lack of knowledge about the disorder. Increased research will reveal vital information needed to formulate effective treatments and therapies.
Topographical disorientation, also known as topographical agnosia and topographagnosia, is the inability to orient oneself in one's surroundings as a result of focal brain damage. This disability may result from the inability to make use of selective spatial information (e.g., environmental landmarks) or to orient by means of specific cognitive strategies such as the ability to form a mental representation of the environment, also known as a cognitive map. It may be part of a syndrome known as visuospatial dysgnosia.
Visuospatial dysgnosia is a loss of the sense of "whereness" in the relation of oneself to one's environment and in the relation of objects to each other. Visuospatial dysgnosia is often linked with topographical disorientation.
There is currently no known curative treatment for SD. The average duration of illness is 8–10 years, and its progression cannot be slowed. Progression of SD can lead to behavioral and social difficulties, thus supportive care is essential for improving quality of life in SD patients as they grow more incomprehensible.
Continuous practice in lexical learning has been shown to improve semantic memory in SD patients.
SD has no known preventative measures.