Drug-induced amnesia

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Drug-induced amnesia is amnesia caused by drugs. Amnesia may be therapeutic for medical treatment or for medical procedures, or it may be a side-effect of a drug, such as alcohol, or certain medications for psychiatric disorders, such as benzodiazepines. [1] It is seen also with slow acting parenteral general anaesthetics.[ citation needed ]

Contents

Medical usage

Amnesia is desirable during surgery, so general anaesthesia procedures are designed to induce it for the duration of the operation. Sedatives such as benzodiazepines, which are commonly used for anxiety disorders, can reduce the encoding of new memories, particularly in high doses (for example, prior to surgery in order for a person not to recall the surgery). [2] Amnestic drugs can be used to induce a coma for a child breathing using mechanical ventilation, or to help reduce intracranial pressure after head trauma. [3] [ failed verification ]

Researchers are currently experimenting with drugs which induce amnesia in order to improve understanding of human memory, and develop better drugs to treat psychiatric disorders and memory-related disorders. People with Alzheimer's disease and other forms of dementia are likely to benefit. By understanding the ways in which amnesia-inducing drugs interact with the brain, researchers hope to better understand the ways in which neurotransmitters aid in the formation of memory. By stimulating rather than depressing these neurotransmitters, memory may improve. [1]

Holmes et al. (2010) [4] commented that the media misrepresented two recent studies as research on "erasing" traumatic memories, but showed the fear response associated with stressful memory could be greatly reduced whilst the factual memory of the trauma remained intact. Similarly, Brunet et al. (2008) found that the people with chronic posttraumatic stress disorder who were treated with propranolol for a single day had a reduced response to existing trauma while retaining memory of the trauma. [5] In the process of remembering, the memory needs to be restored in the brain. By introducing an amnesia-inducing drug during this process, the memory can be disrupted. While the memory remains intact, the emotional reaction is damped, making the memory less overwhelming. Researchers believe this drug will help patients with post-traumatic stress disorder be able to better process the trauma without reliving the trauma emotionally.[ citation needed ] This has raised legal and ethical concerns should drugs be found to have altered the memory of traumatic events that occur in victims of crimes (e.g. murder attempt), and whether it is therapeutically desirable to do so. [4] [6]

Non-medical drug-induced amnesia

Amnesia can result from a side-effect of prescription or non-prescription drugs. Both substance use and alcohol can cause both long-term and short-term memory loss, resulting in blackouts.

The most commonly used group of prescription drugs which can produce amnesia are benzodiazepines, especially if combined with alcohol, however, in limited quantities, triazolam (Halcion) is not associated with amnesia or memory impairment. [7]

In mythology

Nepenthe, literally named anti-sorrow, is a substance mentioned in the Odyssey given to Helen of Troy, said to originate from Egypt. Consumption causes sorrowful memories to be forgotten. [12] [13]

References

  1. 1 2 Curran, H. Valerie (2000). "Psychopharmacological Perspectives on Memory". In E. Tulving; F. I. M. Craik (eds.). Oxford Handbook of Memory. Oxford: Oxford University Press. pp. 539–554.
  2. Baddeley, Alan (2002). The handbook of memory disorders. New York: J. Wiley. pp. 127–8. ISBN   0470856300.
  3. Bernstein, Daniel (2003). Pediatrics for Medical Students . Philadelphia: Lippincott Williams & Wilkins. ISBN   0781729416.
  4. 1 2 Holmes, Emily A.; Sandberg, Anders; Iyadurai, Lalitha (2010). "Erasing trauma memories" (PDF). British Journal of Psychiatry. 197 (5). Royal College of Psychiatrists: 414–415. doi: 10.1192/bjp.197.5.414b . ISSN   0007-1250. PMID   21037221.
  5. Brunet, Alain; Orr, Scott P.; Tremblay, Jacques; Robertson, Kate; Nader, Karim; Pitman, Roger K. (May 2008). "Effect of post-retrieval propranolol on psychophysiologic responding during subsequent script-driven traumatic imagery in post-traumatic stress disorder" . J Psychiatr Res. 42 (6): 503–6. doi:10.1016/j.jpsychires.2007.05.006. PMID   17588604.
  6. Steckler, Thomas; Risbrough, Victoria (2012). "Pharmacological treatment of PTSD – Established and new approaches". Neuropharmacology. 62 (2): 617–627. doi: 10.1016/j.neuropharm.2011.06.012 . PMC   3204327 . PMID   21736888.
  7. Sadock, Benjamin (2008). Kaplan & Sadock's concise textbook of clinical psychiatry. Philadelphia: Wolters Kluwer/Lippincott Williams & Wilkins. ISBN   978-0781787468.
  8. Gray, Richard (2007-07-01). "Scientists find drug to banish bad memories". telegraph.co.uk. Archived from the original on 2009-11-18.
  9. Aelanna. "Dr. Mackenzie's Glossary of Terms". SCP Foundation. Retrieved 2 August 2015.
  10. "NIMH » Memory-sustaining Enzyme May Help Treat PTSD, Cognitive Decline". www.nimh.nih.gov. Archived from the original on 2018-04-23. Retrieved 2016-12-28.
  11. "Scientists raise new questions on molecular key to memory". Ars Technica. Retrieved 2016-12-28.
  12. πένθος . Liddell, Henry George ; Scott, Robert ; A Greek–English Lexicon at the Perseus Project.
  13. Homer; Murray, A.T. (1919). "4.219-221". Odyssey. "4.219-221". Odyssey (in Greek). At the Perseus Project.