Anosognosia
| Anosognosia | |
|---|---|
| Pronunciation | |
| Specialty | Psychiatry, Neurology |
Anosognosia is a condition in which a person with a
Anosognosia is sometimes accompanied by asomatognosia, a form of neglect in which patients deny ownership of body parts such as their limbs. The name derives from Ancient Greek: ἀ-, a- ('without'), νόσος, nosos ('disease'), and γνῶσις, gnōsis ('knowledge').[5] It is considered a disorder that makes the treatment of the patient more difficult, since it may affect negatively the therapeutic relationship.[7]
Causes
Relatively little has been discovered about the cause of the condition since its initial identification. Recent empirical studies tend to consider anosognosia a multi-componential syndrome or multi-faceted phenomenon. That is, it can be manifested by failure to be aware of a number of specific deficits, including motor (
Anosognosia is relatively common following different causes of brain injury, such as stroke and
The condition does not seem to be directly related to
Anosognosia can be selective in that an affected person with multiple impairments may seem unaware of only one handicap, while appearing to be fully aware of any others.[13] This is consistent with the idea that the source of the problem relates to spatial representation of the body. For example, anosognosia for hemiplegia may occur with or without intact awareness of visuo-spatial unilateral neglect. This phenomenon of double dissociation can be an indicator of domain-specific disorders of awareness modules, meaning that in anosognosia, brain damage can selectively impact the self-monitoring process of one specific physical or cognitive function rather than a spatial location of the body.[1][2][14]
There are also studies showing that the maneuver of vestibular stimulation could temporarily improve both the syndrome of spatial unilateral neglect and of anosognosia for left hemiplegia. Combining the findings of hemispheric asymmetry to the right, association with spatial unilateral neglect, and the temporal improvement on both syndromes, it is suggested there can be a spatial component underlying the mechanism of anosognosia for motor weakness and that neural processes could be modulated similarly.[2] There were some cases of anosognosia for right hemiplegia after left hemisphere damage, but the frequency of this type of anosognosia has not been estimated.[1]
Anosognosia may occur as part of
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 with anorexia nervosa.[16] They do not seem to recognize that they have a mental illness. There is evidence that anosognosia related to schizophrenia may be the result of frontal lobe damage.[17]
Diagnosis
Clinically, anosognosia is often assessed by giving patients an anosognosia questionnaire in order to assess their metacognitive knowledge of deficits. However, neither of the existing questionnaires applied in the clinics are designed thoroughly for evaluating the multidimensional nature of this clinical phenomenon; nor are the responses obtained via offline questionnaire capable of revealing the discrepancy of awareness observed from their online task performance.[10][18] The discrepancy is noticed when patients showed no awareness of their deficits from the offline responses to the questionnaire but demonstrated reluctance or verbal circumlocution when asked to perform an online task. For example, patients with anosognosia for hemiplegia may find excuses not to perform a bimanual task even though they do not admit it is because of their paralyzed arms.[18]
A similar situation can happen to patients with anosognosia for cognitive deficits after traumatic brain injury when monitoring their errors during the tasks regarding their memory and attention (online emergent awareness) and when predicting their performance right before the same tasks (online anticipatory awareness).[19] It can also occur among patients with dementia and anosognosia for memory deficit when prompted with dementia-related words, showing possible pre-attentive processing and implicit knowledge of their memory problems.[20] Patients with anosognosia may also overestimate their performance when asked in first-person formed questions but not from a third-person perspective when the questions referring to others.[1][3][18]
When assessing the causes of anosognosia within stroke patients, CT scans have been used to assess where the greatest amount of damage is found within the various areas of the brain. Stroke patients with mild and severe levels of anosognosia (determined by response to an anosognosia questionnaire) have been linked to lesions within the temporoparietal and thalamic regions, when compared to those who experience moderate anosognosia, or none at all.[21] In contrast, after a stroke, people with moderate anosognosia have a higher frequency of lesions involving the basal ganglia, compared to those with mild or severe anosognosia.[21]
Treatment
In regard to anosognosia for neurological patients, no long-term treatments exist. As with
Neurorehabilitation is difficult because, as anosognosia impairs the patient's desire to seek medical aid, it may also impair their ability to seek rehabilitation.[23] A lack of awareness of the deficit makes cooperative, mindful work with a therapist difficult. In the acute phase, very little can be done to improve their awareness, but during this time, it is important for the therapist to build a therapeutic alliance with patients by entering their phenomenological field and reducing their frustration and confusion. Since severity changes over time, no single method of treatment or rehabilitation has emerged or will likely emerge.[24]
See also
- Anosodiaphoria
- Anton–Babinski syndrome
- Body schema
- Body transfer illusion
- Confabulation
- Cotard delusion
- Unilateral neglect(also known as hemispatial neglect)
References
- ^ a b c d e
Moro V, Pernigo S, Zapparoli P, Cordioli Z, Aglioti SM (November 2011). "Phenomenology and neural correlates of implicit and emergent motor awareness in patients with anosognosia for hemiplegia". Behavioural Brain Research. 225 (1): 259–269. S2CID 8389272.
- ^ PMID 17119302.
- ^ a b
Vuilleumier P (February 2004). "Anosognosia: the neurology of beliefs and uncertainties". Cortex; A Journal Devoted to the Study of the Nervous System and Behavior. 40 (1): 9–17. S2CID 4482597.
- ^ a b
Prigatano, George P.; Schacter, Daniel L (1991). Awareness of deficit after brain injury: clinical and theoretical issues. Oxford [Oxfordshire]: Oxford University Press. pp. 53–55. ISBN 978-0-19-505941-0.
- ^ ISBN 978-1-136-87486-4.
- ^
Ramachandran, V. S.; Blakeslee, Sandra (1999). ISBN 978-0-688-17217-6.
- ^ Castillero O (21 October 2016). "Anosognosia". Psicología y Mente (in Spanish). Archived from the original on 2020-04-17.
- PMID 37289520.
- PMID 15716526.
- ^ PMID 19202333.
- .
- PMID 9854262.
- ISBN 978-0-262-08338-6.
- S2CID 2436977.
- S2CID 29284758.
- ^ "Anosognosia/anosognosic - Eating Disorders Glossary". glossary.feast-ed.org. Retrieved 2015-06-23.
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- ^ S2CID 4484058.
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- ^ PMID 1412582.
- PMID 29518705.
- OCLC 496306119.
- S2CID 27815630.
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 978-0-9677189-0-3.
- Berti A, Bottini G, Gandola M, Pia L, Smania N, Stracciari A, et al. (July 2005). "Shared cortical anatomy for motor awareness and motor control". Science. 309 (5733): 488–491. S2CID 8423262.
- Clare L, Halligan P (2006). "Neuropsychological Rehabilitation.". Pathologies of Awareness: Bridging the Gap between Theory and Practice. Taylor & Francis(Psychology Press). ISBN 978-1-84169-810-6.
- Lysaker P, Bell M, Milstein R, Bryson G, Beam-Goulet J (November 1994). "Insight and psychosocial treatment compliance in schizophrenia". Psychiatry. 57 (4): 307–315. PMID 7899525.
- Pia L, Neppi-Modona M, Ricci R, Berti A (April 2004). "The anatomy of anosognosia for hemiplegia: a meta-analysis". Cortex; A Journal Devoted to the Study of the Nervous System and Behavior. 40 (2): 367–377. S2CID 4479704.
- Ramachandran, V. S.; Blakeslee, Sandra (1999). Phantoms in the brain: probing the mysteries of the human mind. New York: Quill. ISBN 978-0-688-17217-6.
- Torrey, E. Fuller (2012). The Insanity Offense. New York: W.W. Norton & Company. pp. 111–122. ISBN 978-0-393-34137-9.
- Vuilleumier P (February 2004). "Anosognosia: the neurology of beliefs and uncertainties". Cortex; A Journal Devoted to the Study of the Nervous System and Behavior. 40 (1): 9–17. S2CID 4482597.