| Aphasia | |
|---|---|
| Classification and external resources | |
| ICD-10 | F80.0-F80.2, R47.0 |
| ICD-9 | 315.31, 784.3, 438.11 |
| DiseasesDB | 4024 |
| MedlinePlus | 003204 |
| eMedicine | neuro/437 |
| MeSH | D001037 |
| Dysphasia | |
|---|---|
| Classification and external resources | |
| ICD-10 | F80.1, F80.2, R47.0 |
| ICD-9 | 438.12, 784.5 |
Aphasia (
/əˈfeɪʒə/ or /əˈfeɪziə/, from ancient Greek ἀφασία (ἄφατος, ἀ- + φημί), "speechlessness"[1]) is an impairment of language ability. This class of language disorder ranges from having difficulty remembering words to being completely unable to speak, read, or write.
Acute aphasia disorders usually develop quickly as a result of head injury or stroke, and progressive forms of aphasia develop slowly from a brain tumor, infection, or dementia.[2][3] The area and extent of brain damage or atrophy will determine the type of aphasia and its symptoms. Aphasia types include expressive aphasia, receptive aphasia, conduction aphasia, anomic aphasia, global aphasia, primary progressive aphasias and many others (see Category:Aphasias). Medical evaluations for the disorder range from clinical screenings by a neurologist to extensive tests by a Speech-Language Pathologist.[2][4]
Most acute aphasia patients can recover some or most skills by working with a Speech-Language Pathologist. This rehabilitation can take two or more years and is most effective when begun quickly. Only a small minority will recover without therapy, such as those suffering a mini-stroke. Improvement varies widely, depending on the aphasia's cause, type, and severity. Recovery also depends on the patient's age, health, motivation, handedness, and educational level.[2]
Contents |
Classification [link]
Classifying the different subtypes of aphasia is difficult and has led to disagreements among experts. The localizationist model is the original model, but modern anatomical techniques and analyses have shown that precise connections between brain regions and symptom classification don't exist. The neural organization of language is complicated; language is a comprehensive and complex behavior and it makes sense that it isn't the product of some small, circumscribed region of the brain.
No classification of patients in subtypes and groups of subtypes is adequate. Only about 60% of patients will fit in a classification scheme such as fluent/nonfluent/pure aphasias. There is a huge variation among patients with the same diagnosis, and aphasias can be highly selective. For instance, patients with naming deficits (anomic aphasia) might show an inability only for naming buildings, or people, or colors.[5]
Localizationist model [link]
The localizationist model attempts to classify the aphasia by major characteristics and then link these to areas of the brain in which the damage has been caused. The initial two categories here were devised by early neurologists working in the field, namely Paul Broca and Carl Wernicke. Other researchers have added to the model, resulting in it often being referred to as the "Boston-Neoclassical Model".
- Individuals with expressive aphasia (also called Broca's aphasia) were once thought to have frontal lobe damage, though more recent work by Dr. Nina Dronkers using imaging and 'lesion analysis' has revealed that patients with Expressive aphasia have lesions to the medial insular cortex. Broca missed these lesions because his studies did not dissect the brains of diseased patients, so only the more temporal damage was visible. Dronkers and Dr. Odile Plaisant scanned Broca's original patients' brains using a non-invasive MRI scanner to take a closer look. [6] Damage to a region of the motor association cortex in the left frontal lobe (Broca's area) disrupts the ability to speak.[7] Individuals with Expressive aphasia often have right-sided weakness or paralysis of the arm and leg, because the frontal lobe is also important for body movement. Video clips showing patients with Expressive-type aphasia can be found here.
- In contrast to Expressive aphasia, damage to the temporal lobe may result in a fluent aphasia that is called receptive aphasia (also known as Sensory aphasia and Wernicke's aphasia). These individuals usually have no body weakness, because their brain injury is not near the parts of the brain that control movement. A video clip with a patient exhibiting Receptive aphasia can be found here
- Working from Wernicke's model of aphasia, Ludwig Lichtheim proposed five other types of aphasia, but these were not tested against real patients until modern imaging made more in-depth studies available. The other five types of aphasia in the localizationist model are:
- Auditory verbal agnosia (also known as Pure Word Deafness)
- Conduction aphasia
- Apraxia of speech (now considered a separate disorder in itself)
- Transcortical motor aphasia (also known as Adynamic aphasia and Extrasylvian motor aphasia)
- Transcortical sensory aphasia
- Anomic aphasia, also known as Anomia, is another type of aphasia proposed under what is commonly known as the Boston-Neoclassical model, which is essentially a difficulty with naming.
- Global aphasia, results from damage to extensive portions of the perisylvian region of the brain. An individual with global aphasia will have difficulty understanding both spoken and written language and will also have difficulty speaking. This is a severe type of aphasia which makes it quite difficult when communicating with the individual.[8]
- Isolation Aphasia, also known as Mixed Transcortical Aphasia, is a type of disturbance in language skill that causes the inability to comprehend what is being said to you or the difficulty in creating speech with meaning without affecting the ability to recite what has been said and to acquire newly presented words. This type of aphasia is caused by brain damage that isolates the parts of the brain from other parts of the brain that are in charge of speech.[9] The brain damages are caused to left temporal/parietal cortex that spares the Wernicke's area. Isolation aphasia patients can repeat what other people say, thus they do recognize words but they can't comprehend the meaning of what they hear and repeat themselves. However, they can not produce meaningful speech of their own. [10]
Progressive aphasias [link]
Primary progressive aphasia (PPA) is associated with progressive illnesses or dementia, such as frontotemporal dementia / Pick Complex Motor neuron disease, Progressive supranuclear palsy, and Alzheimer's disease; which is the gradual process of losing the ability to think. It is characterized by the gradual loss of the ability to name objects. People suffering from PPA may have difficulties comprehending what others are saying. They can also have difficulty trying to find the right words to make a sentence.[11][12][13] There are three classifications of Primary Progressive Aphasia : Progressive nonfluent aphasia (PNFA), Semantic Dementia (SD), and Logopenic progressive aphasia (LPA)[14]
Progressive Jargon Aphasia is a fluent or receptive aphasia in which the patient's speech is incomprehensible, but appears to make sense to them. Speech is fluent and effortless with intact syntax and grammar, but the patient has problems with the selection of nouns. They will either replace the desired word with another that sounds or looks like the original one, or has some other connection, or they will replace it with sounds. Accordingly, patients with jargon aphasia often use neologisms, and may perseverate if they try to replace the words they can't find with sounds. Commonly, substitutions involve picking another (actual) word starting with the same sound (e.g. clocktower - colander), picking another semantically related to the first (e.g. letter - scroll), or picking one phonetically similar to the intended one (e.g. lane - late).
Fluent, non-fluent and "pure" aphasias [link]
The different types of aphasia can be divided into three categories: fluent, non-fluent and "pure" aphasias.[15]
- Receptive aphasias, also called Fluent aphasias, are impairments related mostly to the input or reception of language, with difficulties either in auditory verbal comprehension or in the repetition of words, phrases, or sentences spoken by others. Speech is easy and fluent, but there are difficulties related to the output of language as well, such as paraphasia. Examples of fluent aphasias are: Receptive aphasia, Transcortical sensory aphasia, Conduction aphasia, Anomic aphasia[15]
- Expressive aphasias, also called Nonfluent aphasias, are difficulties in articulating, but in most cases there is relatively good auditory verbal comprehension. Examples of nonfluent aphasias are: Expressive aphasia, Transcortical motor aphasia, Global aphasia[15]
- "Pure" aphasias are selective impairments in reading, writing, or the recognition of words. These disorders may be quite selective. For example, a person is able to read but not write, or is able to write but not read. Examples of pure aphasias are: Pure alexia, Agraphia, Auditory verbal agnosia[15]
Primary and secondary cognitive processes [link]
Aphasias can be divided into primary and secondary cognitive processes.
- Primary aphasia is due to problems with cognitive language-processing mechanisms, which can include: Transcortical sensory aphasia, Semantic Dementia, Apraxia of speech, Progressive nonfluent aphasia, and Expressive aphasia
- Secondary aphasia is the result of other problems, like memory impairments, attention disorders, or perceptual problems, which can include: Transcortical motor aphasia, Dynamic aphasia, Anomic aphasia, Receptive aphasia, Progressive jargon aphasia, Conduction aphasia, and Dysarthria.[16]
Cognitive neuropsychological model [link]
The cognitive neuropsychological model builds on cognitive neuropsychology. It assumes that language processing can be broken down into a number of modules, each of which has a specific function.[17] Hence there is a module which recognises phonemes as they are spoken and a module which stores formulated phonemes before they are spoken. Use of this model clinically involves conducting a battery of assessments (usually from the PALPA, the "psycholinguistic assessment of language processing in adult acquired aphasia ... that can be tailored to the investigation of an individual patient's impaired and intact abilities" [18]), each of which tests one or a number of these modules. Once a diagnosis is reached as to where the impairment lies, therapy can proceed to treat the individual module.
Signs and symptoms [link]
People with aphasia may experience any of the following behaviors due to an acquired brain injury, although some of these symptoms may be due to related or concomitant problems such as dysarthria or apraxia and not primarily due to aphasia.
- inability to comprehend language
- inability to pronounce, not due to muscle paralysis or weakness
- inability to speak spontaneously
- inability to form words
- inability to name objects
- poor enunciation
- excessive creation and use of personal neologisms
- inability to repeat a phrase
- persistent repetition of phrases
- paraphasia (substituting letters, syllables or words)
- agrammatism (inability to speak in a grammatically correct fashion)
- dysprosody (alterations in inflexion, stress, and rhythm)
- incomplete sentences
- inability to read
- inability to write
- limited verbal output
- difficulty in naming
- Speech disorder
Presentation [link]
Acute Aphasias
The following table summarizes some major characteristics of different acute of aphasia:
| Type of aphasia | Repetition | Naming | Auditory comprehension | Fluency |
|---|---|---|---|---|
| Receptive aphasia | mild–mod | mild–severe | defective | fluent paraphasic |
| Transcortical sensory aphasia | good | mod–severe | poor | fluent |
| Conduction aphasia | poor | poor | relatively good | fluent |
| Anomic aphasia | mild | mod–severe | mild | fluent |
| Expressive aphasia | mod–severe | mod–severe | mild difficulty | non-fluent, effortful, slow |
| Transcortical motor aphasia | good | mild–severe | mild | non-fluent |
| Global aphasia | poor | poor | poor | non-fluent |
| Mixed transcortical aphasia | moderate | poor | poor | non-fluent |
- Individuals with Receptive aphasia may speak in long sentences that have no meaning, add unnecessary words, and even create new "words" (neologisms). For example, someone with Receptive aphasia may say, "You know that smoodle pinkered and that I want to get him round and take care of him like you want before", meaning "The dog needs to go out so I will take him for a walk". They have poor auditory and reading comprehension, and fluent, but nonsensical, oral and written expression. Individuals with Receptive aphasia usually have great difficulty understanding the speech of both themselves and others and are therefore often unaware of their mistakes.
- Individuals with Transcortical sensory aphasia Similar deficits as in Receptive aphasia, but repetition ability remains intact.
- Individuals with Conduction aphasia is caused by deficits in the connections between the speech-comprehension and speech-production areas. This might be caused by damage to the arcuate fasciculus, the structure that transmits information between Wernicke's area and Broca's area. Similar symptoms, however, can be present after damage to the insula or to the auditory cortex. Auditory comprehension is near normal, and oral expression is fluent with occasional paraphasic errors. Repetition ability is poor.
- Individuals with Anomic aphasia is essentially a difficulty with naming. The patient may have difficulties naming certain words, linked by their grammatical type (e.g. difficulty naming verbs and not nouns) or by their semantic category (e.g. difficulty naming words relating to photography but nothing else) or a more general naming difficulty. Patients tend to produce grammatic, yet empty, speech. Auditory comprehension tends to be preserved.
- Individuals with Expressive aphasia frequently speak short, meaningful phrases that are produced with great effort. Expressive aphasia is thus characterized as a nonfluent aphasia. Affected people often omit small words such as "is", "and", and "the". For example, a person with Expressive aphasia may say, "Walk dog" which could mean "I will take the dog for a walk", "You take the dog for a walk" or even "The dog walked out of the yard". Individuals with Expressive aphasia are able to understand the speech of others to varying degrees. Because of this, they are often aware of their difficulties and can become easily frustrated by their speaking problems. It is associated with right
- Individuals with Transcortical motor aphasia Similar deficits as Expressive aphasia, except repetition ability remains intact. Auditory comprehension is generally fine for simple conversations, but declines rapidly for more complex conversations. It is associated with right hemiparesis, meaning that there can be paralysis of the patient's right face and arm.
- Individuals with Global aphasia have severe communication difficulties and will be extremely limited in their ability to speak or comprehend language. They may be totally nonverbal, and/or only use facial expressions and gestures to communicate. It is associated with right hemiparesis, meaning that there can be paralysis of the patient's right face and arm.
- Individuals with Mixed transcortical aphasia have similar deficits as in global aphasia, but repetition ability remains intact.
Subcortical aphasias
- Subcortical aphasias Characteristics and symptoms depend upon the site and size of subcortical lesion. Possible sites of lesions include the thalamus, internal capsule, and basal ganglia.
Causes [link]
Aphasia usually results from lesions to the language-relevant areas of the frontal, temporal and parietal lobes of the brain, such as Broca's area, Wernicke's area, and the neural pathways between them. These areas are almost always located in the left hemisphere, and in most people this is where the ability to produce and comprehend language is found. However, in a very small number of people, language ability is found in the right hemisphere. In either case, damage to these language areas can be caused by a stroke, traumatic brain injury, or other brain injury.
Aphasia may also develop slowly, as in the case of a brain tumor or progressive neurological disease, e.g., Alzheimer's or Parkinson's disease. It may also be caused by a sudden hemorrhagic event within the brain. Certain chronic neurological disorders, such as epilepsy or migraine, can also include transient aphasia as a prodromal or episodic symptom.[19]
Aphasia can result from Herpes Simplex virus (HSV) encephalitis. The (HSV) affects the frontal and temporal lobes, subcortical structures and the hippocampal tissue which can trigger aphasia. [20]
Aphasia is also listed as a rare side effect of the fentanyl patch, an opioid used to control chronic pain.[21]
Management [link]
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 isn't consistency on treatment methodology in literature, there is a strong indication that treatment in general has positive outcomes.[22]
A multi-disciplinary team, including doctors (often a physician is involved, but more likely a clinical neuropsychologist will head the treatment team), physiotherapist, occupational therapist, speech-language pathologist, and social worker, works together in treating aphasia. For the most part, treatment relies heavily on repetition and aims to address language performance by working on task-specific skills. The primary goal is to help the individual and those closest to them adjust to changes and limitations in communication.[22]
Treatment techniques mostly fall under two approaches:
- Substitute Skill Model - an approach that uses an aid to help with spoken language, i.e. a writing board
- Direct Treatment Model - an approach which targets deficits with specific exercises[22]
Several treatment techniques include the following:
- Visual Communication Therapy (VIC) - the use of index cards with symbols to represent various components of speech
- Visual Action Therapy (VAT) - involves training individuals to assign specific gestures for certain objects
- 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 patients and clinicians. In this kind of therapy the focus is on pragmatic communication rather than treatment itself. Patients are asked to communicate a given message to their therapists by means of drawing, making hand gestures or even pointing to an object.[23]
- Other - i.e. drawing as a way of communicating, trained conversation partners[22]
More recently, computer technology has been incorporated into treatment options. A key indication for good prognosis is treatment intensity. A minimum of 2–3 hours per week has been specified to produce positive results.[24] The main advantage of using computers is that it can greatly increase intensity of therapy. These programs consist of a large variety of exercises and can be done at home in addition to face-to-face treatment with a therapist. However, since aphasia presents differently among individuals, these programs must be dynamic and flexible in order to adapt to the variability in impairments. Another barrier is the capability of computer programs to imitate normal speech and keep up with the speed of regular conversation. Therefore, computer technology seems to be limited in a communicative setting, however is effective in producing improvements in communication training.[24]
Several examples of programs used are StepByStep, Linguagraphica, Computer-Based Visual Communication (C-VIC), TouchSpeak (TS), and Sentence Shaper.[24]
Melodic intonation therapy is often used to treat non-fluent aphasia and has proved to be very effective in some cases.[25]
Zolpidem, a drug with the trade name of Ambien, may provide short-lasting but effective improvement in symptoms of aphasia present in some survivors of stroke. The mechanism for improvement in these cases remains unexplained and is the focus of current research by several groups, to explain how a drug which acts as a hypnotic-sedative in people with normal brain function, can paradoxically increase speech ability in people recovering from severe brain injury. Use of zolpidem for this application remains experimental at this time, and is not officially approved by any pharmaceutical manufacturers of zolpidem or medical regulatory agencies worldwide.
History [link]
The first recorded case of aphasia is from an Egyptian papyrus, the Edwin Smith Papyrus, which details speech problems in a person with a traumatic brain injury to the temporal lobe.[26]
Notable cases [link]
See also [link]
References [link]
- ^ ἀφασία, Henry George Liddell, Robert Scott, A Greek-English Lexicon, on Perseus
- ^ a b c "Aphasia". MedicineNet.com. https://www.medicinenet.com/aphasia/article.htm. Retrieved 2011-05-23.
- ^ "American Speech-Language-Hearing Association (ASHA):- Aphasia Causes and Number". https://www.asha.org/public/speech/disorders/AphasiaCauses.htm.
- ^ "American Speech-Language-Hearing Association (ASHA):- Aphasia". https://www.asha.org/public/speech/disorders/Aphasia/.
- ^ Kolb, Bryan; Whishaw, Ian Q. (2003). Fundamentals of human neuropsychology. [New York]: Worth. pp. 502, 505, 511. ISBN 0-7167-5300-6. OCLC 464808209.
- ^ Dronkers NF, Plaisant O, Iba-Zizen MT, Cabanis EA (May 2007). "Paul Broca's historic cases: high resolution MR imaging of the brains of Leborgne and Lelong". Brain 130 (Pt 5): 1432–41. DOI:10.1093/brain/awm042. PMID 17405763. https://brain.oxfordjournals.org/content/130/5/1432.long.
- ^ Masdeu, Joseph (June 2000). "Aphasia". Archives of Neurology 57 (6).
- ^ Taylor Sarno, M. (2007). Neurogenic disorders of speech and language. In: O’Sullivan, S.B. & Schmitz, T.J. (2007). Physical Rehabilitation (5th ed.). Philadelphia (PA): F.A. Davis Company.
- ^ Carlson, Neil (2007). Psychology the Science of Behaviour. Toronto: Pearson. pp. 278. ISBN 978-0-205-64524-4.
- ^ Carlson, Neil (2007). Psychology the Science of Behaviour. Toronto: Pearson. pp. 305. ISBN 978-0-205-64524-4.
- ^ Mesulam MM (April 2001). "Primary progressive aphasia". Ann. Neurol. 49 (4): 425–32. DOI:10.1002/ana.91.abs. PMID 11310619.
- ^ Wilson SM, Henry ML, Besbris M, et al. (July 2010). "Connected speech production in three variants of primary progressive aphasia". Brain 133 (Pt 7): 2069–88. DOI:10.1093/brain/awq129. PMC 2892940. PMID 20542982. https://brain.oxfordjournals.org/content/133/7/2069.long#xref-ref-18-1.
- ^ Harciarek M, Kertesz A (September 2011). "Primary progressive aphasias and their contribution to the contemporary knowledge about the brain-language relationship". Neuropsychol Rev 21 (3): 271–87. DOI:10.1007/s11065-011-9175-9. PMC 3158975. PMID 21809067. https://www.springerlink.com/content/3334m228j54ntq10/?MUD=MP.
- ^ Harciarek M, Kertesz A (September 2011). "Primary progressive aphasias and their contribution to the contemporary knowledge about the brain-language relationship". Neuropsychol Rev 21 (3): 271–87. DOI:10.1007/s11065-011-9175-9. PMC 3158975. PMID 21809067. //www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=3158975.
- ^ a b c d Kolb, Bryan; Whishaw, Ian Q. (2003). Fundamentals of human neuropsychology. [New York]: Worth. pp. 502–504. ISBN 0-7167-5300-6. OCLC 464808209.
- ^ Rohrer JD, Knight WD, Warren JE, Fox NC, Rossor MN, Warren JD (January 2008). "Word-finding difficulty: a clinical analysis of the progressive aphasias". Brain 131 (Pt 1): 8–38. DOI:10.1093/brain/awm251. PMC 2373641. PMID 17947337. https://brain.oxfordjournals.org/content/131/1/8.long.
- ^ Luria's Areas of the Human Cortex Involved in Language Illustrated summary of Luria's book Traumatic Aphasia
- ^ Coltheart, Max; Kay, Janice; Lesser, Ruth (1992). PALPA psycholinguistic assessments of language processing in aphasia. Hillsdale, N.J: Lawrence Erlbaum Associates. ISBN 0-86377-166-1.
- ^ Quigg M, Fountain NB (March 1999). "Conduction aphasia elicited by stimulation of the left posterior superior temporal gyrus". J. Neurol. Neurosurg. Psychiatr. 66 (3): 393–6. PMC 1736266. PMID 10084542. //www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=1736266.
- ^ "Can Herpes Simplex Virus Encephalitis Cause Aphasia". https://www.tandfonline.com.myaccess.library.utoronto.ca/doi/pdf/10.1080/0300443032000088285.
- ^ "Fentanyl Transdermal Official FDA information, side effects and uses". Drug Information Online. https://www.drugs.com/pro/fentanyl-transdermal.html#A02A9CB6-35CF-4F01-A980-C3733E0F861A.
- ^ a b c d O’Sullivan, S. B., & Schmitz, T. J. (2007). Physical rehabilitation. (5th ed.). Philadelphia (PA): F. A. Davis Company.
- ^ Alexander, Michael P; Hillis, Argye E (2008). "Aphasia". In Georg Goldenberg; Bruce L Miller; Michael J Aminoff; Francois Boller; D F Swaab. Neuropsychology and Behavioral Neurology: Handbook of Clinical Neurology. 88. Elsevier Health Sciences. pp. 287-310. ISBN 978-0-444-51897-2. OCLC 733092630.
- ^ a b c van de Sandt-Koenderman WM (February 2011). "Aphasia rehabilitation and the role of computer technology: can we keep up with modern times?". Int J Speech Lang Pathol 13 (1): 21–7. DOI:10.3109/17549507.2010.502973. PMID 21329407.
- ^ Norton A, Zipse L, Marchina S, Schlaug G (July 2009). "Melodic intonation therapy: shared insights on how it is done and why it might help". Ann. N. Y. Acad. Sci. 1169: 431–6. DOI:10.1111/j.1749-6632.2009.04859.x. PMC 2780359. PMID 19673819. //www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2780359.
- ^ McCrory PR, Berkovic SF (December 2001). "Concussion: the history of clinical and pathophysiological concepts and misconceptions". Neurology 57 (12): 2283–9. PMID 11756611. https://www.neurology.org/cgi/content/abstract/57/12/2283.
- ^ Richardson, Robert G. (1995). Emerson: the mind on fire: a biography. Berkeley: University of California Press. ISBN 0-520-08808-5. OCLC 31206668.
External links [link]
 |
Look up aphasia or aphemia in Wiktionary, the free dictionary. |
- Academy of Aphasia
- Aphasia at the Open Directory Project
- Luria's Areas of the Human Cortex Involved in Language Illustrated summary of Luria's book Traumatic Aphasia
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https://wn.com/Aphasia
Aphasia (Japanese band)
Aphasia is a female heavy metal/hard rock band from Japan still active today. Their latest release is Sweet Illusion.
Discography
References
External links
Aphasia (disambiguation)
Aphasia is a loss of the ability to produce and/or comprehend language. The term may also refer to:
See also
Nat
Nat or NAT may refer to:
People
"Nat" may be a diminutive for:
Places
Entertainment
Society and culture
Commerce
Organizations
Nat (spirit)
The nats (Burmese: နတ်; MLCTS: nat; IPA: [naʔ]) are spirits worshipped in Burma (or Myanmar) in conjunction with Buddhism. They are divided between the 37 Great Nats and all the rest (i.e., spirits of trees, water, etc.). Almost all of the 37 Great Nats were human beings who met violent deaths (စိမ်းသေ, lit. "green death"). They may thus also be called nat sein (နတ်စိမ်း; lit. green spirits). The word 'sein', while meaning 'green', is being used to mean 'raw' in this context. There are however two types of nats in Burmese Buddhist belief.
Nat spirits are termed lower nats or auk nats (အောက်နတ်), whether named or unnamed, whereas ahtet nats (အထက်နတ်) or higher nat dewas inhabit the six heavens. Much like sainthood, nats can be designated for a variety of reasons, including those only known in certain regions in Burma. Nat worship is less common in urban areas than in rural areas, and is practised among ethnic minorities as well as in the mainstream Bamar society. It is however among the Buddhist Bamar that the most highly developed form of ceremony and ritual is seen.
Nat (Muslim)
The Nat are a Muslim community found in North India. A few are also found in the Terai region of Nepal. They are Muslim converts from the Hindu Nat caste.
History and origin
The Muslim Nat are a semi-nomadic community, traditionally associated rope dancing, juggling, fortune telling and begging. The Nat of Bihar are said to have immigrated from Middle east and Central Asia. They are found mainly in the districts of Madhubani, Darbhanga, Samastipur and Patna. They speak Urdu.
Present circumstances
The Muslim Nat are now mainly cattle dealers, while small number are involved in begging. They are one of the most marganalized Muslim community in Bihar. Almost all the Nat are landless. A small number of Nat have now settled down and are cultivators.
The Nat are strictly endogamous, and generally live in isolation from other Muslim communities in their neighbourhood. Although they are Sunni Muslims, they incorporate many folk beliefs.
In Uttar Pradesh, the Nat are said to have come originally from Chittaur in Rajasthan. They are found mainly in the districts of Varanasi, Allahabad, Barabanki and Jaunpur. The Nat speak Urdu and Hindi and converted to Islam during the rule of the Nawabs of Awadh, about two hundred years ago. The Muslim Nat consist of number of sub-groups, the main ones being the Aman, Goleri, Mahawat, Rari, Siarmaroa and Turkata. Many Nat are still involved with fortune telling and live a semi-nomadic lifestyle. Most Nat are now landless agricultural labourers, and are in depressed economic circumstances. The Nat are Sunni Muslims, but incorporate many folk beliefs.
