Anosognosia

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Anosognosia
ICD-10 R41.8
ICD-9 780.9

Anosognosia is a condition in which a person who suffers disability seems unaware of or denies the existence of his or her disability. This may include unawareness of quite dramatic impairments, such as blindness or paralysis. It was first named by neurologist Joseph Babinski in 1914, although relatively little has been discovered about the cause of the condition since its initial identification. The word comes from the Greek words "nosos" disease and "gnosis" knowledge.

Contents

[edit] Neurology

Anosognosia is relatively common following brain injury (e.g. 10%–18% in the case of hemiplegia/hemiparesis after stroke[1]), but can appear to occur in conjunction with virtually any neurological impairment. However, it is not related to global mental confusion (see delirium), cognitive flexibility, or other major intellectual disturbance. Anosognosia can be selective in that an affected person with multiple impairments may only seem unaware of one handicap, while appearing to be fully aware of any others. Those diagnosed with dementia of the Alzheimer's type often display this lack of awareness and insist that "There is nothing wrong with me!".

The condition does not seem to be directly related to sensory loss and is thought to be caused by damage to higher level neurocognitive processes which are involved in integrating sensory information with processes which support spatial or bodily representations (including the somatosensory system). Anosognosia is thought to be related to unilateral neglect, a condition often found after damage to the non-dominant (usually the right[2]) hemisphere of the cerebral cortex in which sufferers seem unable to attend to, or sometimes comprehend, anything on a certain side of their body[3] (usually the left).

[edit] Psychiatry

Although largely used to describe unawareness of impairment after brain injury or stroke, the term 'anosognosia' is occasionally used to describe the lack of insight shown by some people who suffer from psychosis, and who therefore do not have the insight to recognize that they suffer from a mental illness.

On reviewing the applicable literature, one researcher concluded that: "Poor insight in schizophrenia is associated with poorer medication compliance, poorer psychosocial functioning, poorer prognosis, increased relapses and hospitalization and poorer treatment outcomes."[4]

The three kinds of insight that are most vulnerable to severe mental illnesses are the awareness:[5]

  1. that a person is suffering from a mental disorder
  2. of the effects of medication; and
  3. of the social consequences of having a mental disorder.

[edit] Treatment

In regard to psychiatric patients, empirical studies verify that, for individuals with severe mental illnesses, lack of awareness of illness is significantly associated with both medication non-compliance and re-hospitalization.[6] Fifteen percent of individuals with severe mental illnesses who refuse to take medication voluntarily under any circumstances may require some form of coercion to remain compliant because of anosognosia.[7]

One study of voluntary and involuntary inpatients confirmed that committed patients require coercive treatment because they fail to recognize their need for care.[8] Predictably, the patients committed to the hospital had significantly lower measures of insight than the voluntary patients.

Anosognosia is also intimately related to other cognitive dysfunctions that may impair the capacity to continuously participate in treatment.[8] Other research has suggested that attitudes toward treatment can improve after involuntary treatment and that previously committed patients tend to later seek voluntary treatment.[9]

In regard to anosognosia for neurological patients, there are currently no long-term treatments for anosognosia, although, like unilateral neglect, caloric reflex testing (squirting ice cold water into the left ear) is known to temporarily ameliorate unawareness of impairment. It is not entirely clear how this works, although it is thought that the unconscious shift of attention or focus caused by the intense stimulation of the vestibular system temporarily influences awareness. Most cases of anosognosia appear to simply disappear over time, while other cases can last indefinitely. Normally, long-term cases are treated with cognitive therapy to train the patient to adjust for their inoperable limbs (though it is believed that these patients still are not "aware" of their disability).

[edit] See also

[edit] Footnotes

  1. ^ B Baier and H Karnath (2005 March), "Incidence and diagnosis of anosognosia for hemiparesis revisited", J Neurol Neurosurg Psychiatry 76 (3): 358–361, doi:10.1136/jnnp.2004.036731, http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1739568 
  2. ^ Breier J, Adair J C, Gold M, Fennell E, Gilmore R, Heilman K (1995), "Dissociation of anosognosia for hemiplegia and aphasia during left-hemisphere anesthesia", Neurology 45 (1), http://cat.inist.fr/?aModele=afficheN&cpsidt=3452304 
  3. ^ K M Heilman, A M Barrett, and J C Adair (1998 November 29), "Possible mechanisms of anosognosia: a defect in self-awareness", Philosophical Transactions of the Royal Society B: Biological Sciences 353 (1377): 1903–1909, http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1692420 
  4. ^ Schwartz RC (1998). "The relationship between insight, illness and treatment outcome in schizophrenia". Psychiatr Q 69 (1): 1–22. PMID 9536472. 
  5. ^ Amador XF, Strauss DH, Yale SA, Flaum MM, Endicott J, Gorman JM (1993). "Assessment of insight in psychosis". Am J Psychiatry 150 (6): 873–9. PMID 8494061. 
  6. ^ McEvoy J (1998). "The Relationship Between Insight in Psychosis and Compliance With Medications". in Xavier F. Amador & Anthony S. David eds. Insight and Psychosis. pp. 299. 
  7. ^ David, Anthony S.; Amador, Xavier Francisco (2004). Insight and psychosis: awareness of illness in schizophrenia and related disorders. Oxford [Oxfordshire]: Oxford University Press. pp. 293. ISBN 0-19-852568-0. 
  8. ^ a b McEvoy JP, Applebaum PS, Apperson LJ, Geller JL, Freter S (1989). "Why must some schizophrenic patients be involuntarily committed? The role of insight". Compr Psychiatry 30 (1): 13–7. doi:10.1016/0010-440X(89)90113-2. PMID 2564330. 
  9. ^ Kane JM, Quitkin F, Rifkin A, Wegner J, Rosenberg G, Borenstein M (1983). "Attitudinal changes of involuntarily committed patients following treatment". Arch. Gen. Psychiatry 40 (4): 374–7. PMID 6838317. 

[edit] Further reading

  • Amador, Xavier Francisco (2000). I am not sick, I don't need help!: helping the seriously mentally ill accept treatment: a practical guide for: families and therapists. Vida Press. ISBN 0-9677189-0-2. 
  • Berti A, Bottini G, Gandola M, et al (2005). "Shared cortical anatomy for motor awareness and motor control". Science 309 (5733): 488–91. doi:10.1126/science.1110625. PMID 16020740. 
  • Clare L, Halligan P (2006). "Neuropsychological Rehabilitation.". Pathologies of Awareness: Bridging the Gap between Theory and Practice. Taylor & Francis(Psychology Press). ISBN 9781841698106. 
  • Lysaker P, Bell M, Milstein R, Bryson G, Beam-Goulet J (1994). "Insight and psychosocial treatment compliance in schizophrenia". Psychiatry 57 (4): 307–15. PMID 7899525. 
  • McGlynn S, Schacter DL (1997). "The Neuropsychology of Insight: Impaired Awareness of Deficits in a Psychiatric Context". Psychiatric Annals 27: 806. 
  • Pia L, Neppi-Modona M, Ricci R, Berti A (2004). "The anatomy of anosognosia for hemiplegia: a meta-analysis". Cortex 40 (2): 367–77. doi:10.1016/S0010-9452(08)70131-X. PMID 15156794. 
  • Pia L, Tamietto M (2006). "Unawareness in schizophrenia: neuropsychological and neuroanatomical findings". Psychiatry Clin. Neurosci. 60 (5): 531–7. doi:10.1111/j.1440-1819.2006.01576.x. PMID 16958934. 
  • Prigatano, George P.; Schacter, Daniel L (1991). Awareness of deficit after brain injury: clinical and theoretical issues. Oxford [Oxfordshire]: Oxford University Press. ISBN 0-19-505941-7. 
  • Ramachandran, V. S.; Blakeslee, Sandra (1999). Phantoms in the brain: probing the mysteries of the human mind. New York: Quill. ISBN 0-688-17217-2. 
  • Vuilleumier P (2004). "Anosognosia: the neurology of beliefs and uncertainties" (PDF). Cortex 40 (1): 9–17. doi:10.1016/S0010-9452(08)70918-3. PMID 15070000. http://labnic.unige.ch/nic/papers/PV_CX2004.pdf. 
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