Dysnomia (disorder)
From Wikipedia, the free encyclopedia
| Dysnomia Classification and external resources |
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| ICD-9 | 784.3 |
|---|---|
Dysnomia is a difficulty or inability to retrieve the correct word from memory when it is needed. Dysnomia can affect speech skills, writing abilities, or both.
Normal individuals will occasionally suffer problems recalling words. This only becomes a medical condition when the recall problems interfere with daily life. Doctors use neuropsychological tests to diagnose the condition.[1]
Dysnomia can develop because of brain trauma or can be a learning disability. Dysnomia from strokes or head injuries will frequently reduce or disappear with time.
The learning disability, however, cannot be cured. Patients can improve their life skills by using coping strategies.
Contents |
[edit] Overview
Word-recall problems become a medical condition when severe enough to interfere with a patient's daily life. Neuropsychological tests of dysnomic individuals show a significant difficulty recalling words or names. [2]
As a long-term condition, dysnomia can be:
- An inherited learning disability [3]
- A symptom of dementia, including Alzheimer's [4]
- A result of brain trauma, including accidents or stroke [5]
- A side-effect of certain drugs [6]
- A result of aging
Dysnomia can also describe a short-term problem in recalling words or names. In this case it is used as a symptom, not as a condition. Dysnomia can be a symptom of alcohol intoxication, low blood sugar, concussion, fluid/electrolyte imbalance, nutritional deficiencies, hyperthermia, hypothermia, hypoxemia, and other conditions and illnesses.
[edit] Symptoms
Dysnomia impairs an individual's ability to succeed in speech and writing tasks.
- People who have dysnomia may replace a word with a synonym in an attempt to express their thoughts without using the word they are having difficulty retrieving [7]
- Dysnomics will take longer to complete tests or leave timed tests incomplete.
- Dysnomics may pause or appear to struggle when trying to recall words or names
[edit] Dysnomia vs. anomia
The difference between dysnomia and anomia is the level of function. This is indicated by the nature of the names, dys-nomia vs. a-nomia. Anomia, "renders a person completely unable to name familiar objects, almost as if he or she were suddenly required to converse in a foreign language". Dysnomia, on the other hand, is a lesser level of dysfunction, a severe form of the "tip-of-the-tongue" feeling where the brain cannot recall the desired word or name. [8] [9]
Despite the difference, some sources interchange the terms. A review of available literature shows:
- The two diagnosis have similar, but separate references in diagnostic codes
- Anomia is cited more frequently/studied more frequently, possibly because anomic patients are more likely to be hospitalized or institutionalized
- Dysnomia appears more common in reference to a learning disability
- In cases where the two terms are used in the same materials, dysnomia is sometimes mentioned as the primary[10], other references place anomia first [11], and other references list both and treat them as synonyms [12].
Despite the separate diagnostic codes, a search of online materials failed to reveal clear clinical criteria for when dysnomia shifts to anomia.
[edit] Dysnomia and expressive aphasia
Dysnomia is a type of expressive aphasia [13] [14]
[edit] Relationship to dyslexia
Some models of dyslexia identify it as being caused by dysnomia. This model, "proposes that the deficit in verbal label retrieval creates a short-term memory deficit resulting in difficulty recalling word labels in reading." [15]
[edit] Testing methods
Doctors use neuropsychological tests to diagnose dysnomia and anomia. The tests can measure the condition's severity and identify/eliminate other neuropsychological conditions with similar symptoms. [16]
Rapid Automatized Naming is a good example of these tests. Rapid Automatized Naming times how quickly the patient can name common objects or colors. A typical test would have the patient rapidly name five pictures of common objects or colors appearing repeatedly on a computer screen. The doctor compares the completion time against average times for the patient's age group. [17]
[edit] Treatment
Doctors recommend different treatments based on the cause of the dysnomia.
Dysnomia caused by a brain trauma, including injury or stroke, is frequently treated by a speech pathologist using exercises to improve recall. (Examples: [18]) For brain trauma cases, doctors recommend that, "language therapy should begin as soon as possible and be tailored to the individual needs of the patient." [19]
Treatment is more difficult when dysnomia is caused by developmental issues. Since the area of the brain dealing with word recall has not fully developed, there is currently no way to cause the development or speed its process. In children with dysnomia, the condition may lessen or disappear as the child grows.
If a medication is causing dysnomia as a side effect, the prescribing doctor can offer alternatives.
A published case study reported that antidepressants helped a dysnomic patient. [20]
