World Library  
Flag as Inappropriate
Email this Article

Selective amnesia

Article Id: WHEBN0009461102
Reproduction Date:

Title: Selective amnesia  
Author: World Heritage Encyclopedia
Language: English
Subject: Source-monitoring error, Active recall, Lu Chao, Lost in the mall technique, Personal-event memory
Collection: Memory Biases, Memory Disorders
Publisher: World Heritage Encyclopedia
Publication
Date:
 

Selective amnesia

Selective amnesia is a type of

  1. ^ Hilgard, E. R., & Hommel, L. S. (1961) Selective amnesia for events within hypnosis in relation to repression. Journal of Personality, 29, 205-216
  2. ^ a b Bertrand, L. D., & Spanos, N. P. (1984). The organization of recall during hypnotic suggestions for complete and selective amnesia. Imagination, Cognition and Personality, 4(3), 249-261
  3. ^ a b Davidson, T. M., & Bowers, K. S. (1991). Selective hypnotic amnesia: Is it a successful attempt to forget or an unsuccessful attempt to remember? Journal of Abnormal Psychology, 100(2), 133-143
  4. ^ a b Clemes, S. R. (1964). Repression and hypnotic amnesia. Journal of Abnormal and Social Psychology, 69, 62-69
  5. ^ Stam, H. J., Radtke-Bodorik, H., & Spanos, N. P. (1980). Repression and hypnotic amnesia: A failure to replicate and an alternative formulation. Journal of Abnormal Psychology, 89(4), 551-559
  6. ^ a b Lewis, D. J., Miller, R. R., & Misanin, J. R. (1969). Selective amnesia in rats produced by electroconvulsive shock. Journal of Comparative and Physiological Psychology, 69(1), 136-140
  7. ^ a b Hölscher, C., & Schmidt, W. J. (1994). Quinolinic acid lesion of the rat entorhinal cortex pars medialis produces selective amnesia in allocentric working memory (WM), but not in egocentric WM. Behavioural Brain Research, 63(2), 187-194
  8. ^ a b Watanabe, S., Yanagisawa, N. (2000). Serial position effect and selective amnesia induced by scopolamine in mice. Nihon Shinkei Seishin Yakurigaku Zasshi = Japanese Journal of Psychopharmacology. 20(1), 17-20
  9. ^ a b Mathis, C., Lehmann, J., Ungerer, A. (1992). The selective protein-kinase-C inhibitor, NPC-15437, induces specific deficits in memory retention in mice. European Journal of Pharmacology. 220(1), 107-110
  10. ^ a b Alexander, L. (1953). The effect of electroshock on a "normal" person under recent stress: An experiment elucidating the influence of electroshock on the defensive operations of the ego. The American Journal of Psychiatry, 109, 696-698
  11. ^ a b Rodrigues, S. (2011). Using chemistry simulations: attention capture, selective amnesia and inattentional blindness. Chemistry Education Research and Practice. 12(1), 40-46
  12. ^ a b Scheerer, M., Goldstei, G. (1966). Denial and selective amnesia following brain damage – A case study. Neuropsychologia. 4(4), 357-363
  13. ^ a b Sirigu, A., & Grafman, J. (1996). Selective impairments within episodic memories. Cortex: A Journal Devoted to the Study of the Nervous System and Behavior, 32(1), 83-95
return p

end

', table.concat(classes, ' '), s )
%s
function p._hatnote(s, options) checkType('_hatnote', 1, s, 'string') checkType('_hatnote', 2, options, 'table', true) local classes = {'hatnote'} local extraclasses = options.extraclasses local selfref = options.selfref if type(extraclasses) == 'string' then classes[#classes + 1] = extraclasses end if selfref then classes[#classes + 1] = 'selfref' end return string.format( '

function p.hatnote(frame) local args = getArgs(frame) local s = args[1] local options = {} if not s then return p.makeWikitextError( 'no text specified', 'Template:Hatnote#Errors', args.category ) end options.extraclasses = args.extraclasses options.selfref = args.selfref return p._hatnote(s, options) end


-- Hatnote -- -- Produces standard hatnote text. Implements the template.


function p._formatLink(link, display) -- Find whether we need to use the colon trick or not. We need to use the -- colon trick for categories and files, as otherwise category links -- categorise the page and file links display the file. checkType('_formatLink', 1, link, 'string') checkType('_formatLink', 2, display, 'string', true) link = removeInitialColon(link) local namespace = p.findNamespaceId(link, false) local colon if namespace == 6 or namespace == 14 then colon = ':' else colon = end -- Find whether a faux display value has been added with the | magic -- word. if not display then local prePipe, postPipe = link:match('^(.-)|(.*)$') link = prePipe or link display = postPipe end -- Find the display value. if not display then local page, section = link:match('^(.-)#(.*)$') if page then display = page .. ' § ' .. section end end -- Assemble the link. if display then return string.format('%s', colon, link, display) else return string.format('%s%s', colon, link) end end

function p.formatLink(frame) local args = getArgs(frame) local link = args[1] local display = args[2] if not link then return p.makeWikitextError( 'no link specified', 'Template:Format hatnote link#Errors', args.category ) end return p._formatLink(link, display) end


-- Format link -- -- Makes a wikilink from the given link and display values. Links are escaped -- with colons if necessary, and links to sections are detected and displayed -- with " § " as a separator rather than the standard MediaWiki "#". Used in -- the template.


function p.makeWikitextError(msg, helpLink, addTrackingCategory) -- Formats an error message to be returned to wikitext. If -- addTrackingCategory is not false after being returned from -- Module:Yesno, and if we are not on a talk page, a tracking category -- is added. checkType('makeWikitextError', 1, msg, 'string') checkType('makeWikitextError', 2, helpLink, 'string', true) yesno = require('Module:Yesno') local title = mw.title.getCurrentTitle() -- Make the help link text. local helpText if helpLink then helpText = ' (help)' else helpText = end -- Make the category text. local category if not title.isTalkPage and yesno(addTrackingCategory) ~= false then category = 'Hatnote templates with errors' category = string.format( '%s:%s', mw.site.namespaces[14].name, category ) else category = end return string.format( '%s', msg, helpText, category ) end

function p.formatPageTables(...) -- Takes a list of page/display tables and returns it as a list of -- formatted links. Nil values are not allowed. local pages = {...} local links = {} for i, t in ipairs(pages) do checkType('formatPageTables', i, t, 'table') local link = t[1] local display = t[2] links[i] = p._formatLink(link, display) end return links end

function p.formatPages(...) -- Formats a list of pages using formatLink and returns it as an array. Nil -- values are not allowed. local pages = {...} local ret = {} for i, page in ipairs(pages) do ret[i] = p._formatLink(page) end return ret end

function p.findNamespaceId(link, removeColon) -- Finds the namespace id (namespace number) of a link or a pagename. This -- function will not work if the link is enclosed in double brackets. Colons -- are trimmed from the start of the link by default. To skip colon -- trimming, set the removeColon parameter to true. checkType('findNamespaceId', 1, link, 'string') checkType('findNamespaceId', 2, removeColon, 'boolean', true) if removeColon ~= false then link = removeInitialColon(link) end local namespace = link:match('^(.-):') if namespace then local nsTable = mw.site.namespaces[namespace] if nsTable then return nsTable.id end end return 0 end

local function removeInitialColon(s) -- Removes the initial colon from a string, if present. return s:match('^:?(.*)') end

local function getArgs(frame) -- Fetches the arguments from the parent frame. Whitespace is trimmed and -- blanks are removed. mArguments = require('Module:Arguments') return mArguments.getArgs(frame, {parentOnly = true}) end


-- Helper functions


local p = {}

local libraryUtil = require('libraryUtil') local checkType = libraryUtil.checkType local mArguments -- lazily initialise Module:Arguments local yesno -- lazily initialise Module:Yesno


return p-------------------------------------------------------------------------------- -- Module:Hatnote -- -- -- -- This module produces hatnote links and links to related articles. It -- -- implements the and meta-templates and includes -- -- helper functions for other Lua hatnote modules. --

end

', table.concat(classes, ' '), s )
%s
function p._hatnote(s, options) checkType('_hatnote', 1, s, 'string') checkType('_hatnote', 2, options, 'table', true) local classes = {'hatnote'} local extraclasses = options.extraclasses local selfref = options.selfref if type(extraclasses) == 'string' then classes[#classes + 1] = extraclasses end if selfref then classes[#classes + 1] = 'selfref' end return string.format( '

function p.hatnote(frame) local args = getArgs(frame) local s = args[1] local options = {} if not s then return p.makeWikitextError( 'no text specified', 'Template:Hatnote#Errors', args.category ) end options.extraclasses = args.extraclasses options.selfref = args.selfref return p._hatnote(s, options) end


-- Hatnote -- -- Produces standard hatnote text. Implements the template.


function p._formatLink(link, display) -- Find whether we need to use the colon trick or not. We need to use the -- colon trick for categories and files, as otherwise category links -- categorise the page and file links display the file. checkType('_formatLink', 1, link, 'string') checkType('_formatLink', 2, display, 'string', true) link = removeInitialColon(link) local namespace = p.findNamespaceId(link, false) local colon if namespace == 6 or namespace == 14 then colon = ':' else colon = end -- Find whether a faux display value has been added with the | magic -- word. if not display then local prePipe, postPipe = link:match('^(.-)|(.*)$') link = prePipe or link display = postPipe end -- Find the display value. if not display then local page, section = link:match('^(.-)#(.*)$') if page then display = page .. ' § ' .. section end end -- Assemble the link. if display then return string.format('%s', colon, link, display) else return string.format('%s%s', colon, link) end end

function p.formatLink(frame) local args = getArgs(frame) local link = args[1] local display = args[2] if not link then return p.makeWikitextError( 'no link specified', 'Template:Format hatnote link#Errors', args.category ) end return p._formatLink(link, display) end


-- Format link -- -- Makes a wikilink from the given link and display values. Links are escaped -- with colons if necessary, and links to sections are detected and displayed -- with " § " as a separator rather than the standard MediaWiki "#". Used in -- the template.


function p.makeWikitextError(msg, helpLink, addTrackingCategory) -- Formats an error message to be returned to wikitext. If -- addTrackingCategory is not false after being returned from -- Module:Yesno, and if we are not on a talk page, a tracking category -- is added. checkType('makeWikitextError', 1, msg, 'string') checkType('makeWikitextError', 2, helpLink, 'string', true) yesno = require('Module:Yesno') local title = mw.title.getCurrentTitle() -- Make the help link text. local helpText if helpLink then helpText = ' (help)' else helpText = end -- Make the category text. local category if not title.isTalkPage and yesno(addTrackingCategory) ~= false then category = 'Hatnote templates with errors' category = string.format( '%s:%s', mw.site.namespaces[14].name, category ) else category = end return string.format( '%s', msg, helpText, category ) end

function p.formatPageTables(...) -- Takes a list of page/display tables and returns it as a list of -- formatted links. Nil values are not allowed. local pages = {...} local links = {} for i, t in ipairs(pages) do checkType('formatPageTables', i, t, 'table') local link = t[1] local display = t[2] links[i] = p._formatLink(link, display) end return links end

function p.formatPages(...) -- Formats a list of pages using formatLink and returns it as an array. Nil -- values are not allowed. local pages = {...} local ret = {} for i, page in ipairs(pages) do ret[i] = p._formatLink(page) end return ret end

function p.findNamespaceId(link, removeColon) -- Finds the namespace id (namespace number) of a link or a pagename. This -- function will not work if the link is enclosed in double brackets. Colons -- are trimmed from the start of the link by default. To skip colon -- trimming, set the removeColon parameter to true. checkType('findNamespaceId', 1, link, 'string') checkType('findNamespaceId', 2, removeColon, 'boolean', true) if removeColon ~= false then link = removeInitialColon(link) end local namespace = link:match('^(.-):') if namespace then local nsTable = mw.site.namespaces[namespace] if nsTable then return nsTable.id end end return 0 end

local function removeInitialColon(s) -- Removes the initial colon from a string, if present. return s:match('^:?(.*)') end

local function getArgs(frame) -- Fetches the arguments from the parent frame. Whitespace is trimmed and -- blanks are removed. mArguments = require('Module:Arguments') return mArguments.getArgs(frame, {parentOnly = true}) end


-- Helper functions


local p = {}

local libraryUtil = require('libraryUtil') local checkType = libraryUtil.checkType local mArguments -- lazily initialise Module:Arguments local yesno -- lazily initialise Module:Yesno


-- Module:Hatnote -- -- -- -- This module produces hatnote links and links to related articles. It -- -- implements the and meta-templates and includes -- -- helper functions for other Lua hatnote modules. --


References

The following section is a summary of a case study performed by Sirigu and Grafman in 1996.[13] Patient B was a male in his fifties. He suffered from a heart attack that caused damage to his cerebral anoxia. Due to his injury, he developed severe selective amnesia for the people and dates associated with both personal and public events. Though he could describe what happened during the event as well as the setting of the event, he could not give any information about the event’s date or the people involved. His amnesia was temporally limited, affecting only his memories of the last two to three decades. This finding suggests that specific aspects of knowledge is stored separately, allowing for selective amnesia to affect one aspect of an event and not another.[13]

Patient B

The following section is a summary of a case study performed by Scheerer and Goldstei in 1966.[12] Patient A was a 36-year-old mechanic, formerly in the Navy, who had a wife and three children. Due to an unfortunate accident, Patient A’s frontal lobe experienced significant damage. This brain damage resulted in a slight decrease in cognitive and physical skills as well as a change in personality. There were also some specific memory problems suggestive of selective amnesia. For example, Patient A worked with the same doctor for many years. However, if the doctor was absent for several days, Patient A was unable to remember him or, if Patient A did remember him, he thought the doctor was a Naval officer. Also, Patient A could only vaguely remember events that happened recently. For instance, he could remember if someone had visited him the day before but could not remember who had visited him. He could also report that he had formerly been in the Navy and that he had a wife and children, but there were many gaps and inconsistencies in his memory. While studying these inconsistencies, Scheerer and Goldstei found that Patient A’s memory was sharpest for positive memories and weakest for negative memories. The study of Patient A gives evidence to the theory that patients with selective amnesia cling to specific memories, specifically positive memories. However, this fixation on positive memories causes patients to misremember negative or neutral life events, causing their memory to appear disjointed and defective.[12]

Patient A

Because of the relative rarity of naturally occurring clinical selective amnesia, many case studies have been undertaken to learn more about the cause and course of the disorder.

Case studies

All people experience selective amnesia in their lives, and this selective amnesia may allow individuals to use their attention more effectively.[11] In these studies, selective amnesia is defined as the phenomena experienced when a participant pays attention to the information given but then almost immediately forgets it. Rodrigues (2011) conducted a study in which participants were put into pairs and each pair was given five minutes to interact with an assigned stimuli. The participants’ actions and speech were recorded during this time. After the five minutes were completed, the experimenter questioned the participants about why the participants made certain decisions or said certain things. Rodrigues found that inattention blindness, attention capture, and selective amnesia all played a role in the participant’s overall accuracy. Thus, even though most other forms of amnesia are harmful, selective amnesia may play a practical, and even helpful, role in our lives.[11]

Selective amnesia in everyday life

It has been suggested that inducing selective amnesia for particular events or stimuli in patients may be an effective tool in psychotherapy.[10] Alexander (1953) found that administering electroconvulsive therapy (ECT) to patients suffering from a traumatic life event induces selective amnesia for the traumatic event without effecting the patient’s surrounding memories. This finding, as well as other similar findings, has been used to form a hypothesis concerning the mechanisms underlying ECT. This hypothesis states that the most decisive effect of ECT is the arousal of the active defensive operations in the brain. They further hypothesize that the arousal of these operations makes ECT an effective treatment for depression and other psychotic disorders in which the brain’s defensive operations are ineffective. This hypothesis would also explain why ECT is an ineffective treatment for disorders in which the defensive operations are overactive such as anxiety disorders. Thus, selective amnesia, if utilized under the correct circumstances, may be useful in a therapeutic setting.[10]

Use in treatment

Some research suggests that selective amnesia may be the result of a deficit in memory consolidation.[9] Mathis and colleagues (1992) investigated the effect of protein kinase C (PKC) on the memories of rats and found that they could induce a dose-dependent deficit in memory retention. They classified this memory deficit as selective amnesia. In this experiment, mice were trained to avoid a certain leg of a Y-shaped maze. After training, the experimenters gave a dose of NPC 15437 to the mice and noticed that the mice exhibited selective amnesia for the temporal aspect of the task but not the spatial aspect. The experimenters eliminated the possibly that this amnesia was due to a deficit in memory acquisition and retrieval, concluding that PKC interferes with the mechanisms behind memory consolidation.[9]

Memory consolidation

Watanabe and Yanagisawa (2000) found that the serial position effect may determine the task’s susceptibility to selective amnesia.[8] In their study, the researchers put mice through a maze with six ‘gates’. Each of these ‘gates’ had three doors, two of them locked and the third unlocked. They found that the mice were better at remembering the position of the unlocked gate if the gate’s position was taught at the beginning or end of the trial. These findings provide support for the primacy effect and recency effect of serial positioning. Watanabe and Yanagisawa then took this a step further and injected some of the mice with high and low doses of scopolamine. At low doses, scopolamine intensified the primacy effect of serial positioning, and at high doses, scopolamine created major defects in general learning abilities. Their findings suggest that scopolamine may contain a property which plays a role in selective amnesia, specifically as it relates to serial positioning.[8]

Serial position

In an experiment investigating the functional role of the entorhinal cortex pars medialis in memory formation, Hölscher and Schmidt (1994) found that they could produce selective amnesia for specific types of memories by creating lesions in the brains of rats.[7] In this experiment, both lesioned and non-lesioned rats were placed in an eight-armed maze with food in one of the arms. The rats had to orientate themselves to their surroundings to find the food. Rats with lesions showed significant memory problems, including memory failure and increased memory retrieval times, during trials in which they had to orient themselves using distal cues, the most distant cues. The researcher labeled these memory problems as selective amnesia. They also found that lesion-ed rats had a more difficult time finding the food when it was moved to a different arm. When the lesion-ed rats had to orient themselves in an egocentric test using proprioceptive cue, there were no detectable memory defects. This finding suggests that the type of memory a subject is trying to remember may influence the subject’s susceptibility to selective amnesia.[7]

Types of memory

One’s familiarity with a task influences how selective amnesia affects the subject’s memories.[6] To study this phenomena, Lewis and colleagues (1969) taught rats a simple passive avoidance task, a fear-aggravated test used to evaluate learning and memory in rodent models. Some rats were allowed to familiarize themselves with the task while others were only allowed to experience the task once. After the rats had completed their task a pre-determined number of times, the experimenters administered an electroconvulsive shock to the rats meant to induce selective amnesia. These shocks varied in duration, lasting from zero to five seconds. The results of this study showed that only the rats unfamiliar with the task demonstrated selective amnesia 24 hours later. The rats that were familiar with the task seemed to display normal memory for the task. Thus, there might be a particular stage in the memory process that is vulnerable to selective amnesia. The current hypothesis is that this vulnerable stage is located during the transition from active memory to short term memory.[6]

Familiarity

People may be more susceptible to hypnotic amnesia if the words they are asked to forget (or remember) have significant emotional connotations.[4] Clemes (1964) was able to identify participants’ critical words—words that are linked with inner conflict—and neutral words—words that are not linked with inner conflict. He then placed the participants under hypnosis and listed nine critical words and nine neutral words. Participants were then instructed, under the influence of hypnosis, to forget half of the words they were given. They found that participants are more likely to forget critical words than neutral words.[4] However, a replication study conducted by Stam and colleagues (1980) failed to replicate these results, suggesting that these conclusions may be invalid.[5]

Emotional connotations

Factors of selective amnesia

[3] In another experiment, Davidson and Bower (1991) found that participants with selective amnesia due to hypnosis were able to remember all non-amnesic information with near perfect recall. They also noticed that the participants recalled this information in very structured ways (usually in the same order the information was given). These results suggest that people experiencing hypnosis are still able to attend to important retrieval cues even though they are not able to recall the material specifically targeted by the amnesia.[2] Bertrand and Spanos (1984) were able to study the process of [3][2] Researchers have used the relationship between hypnosis and selective amnesia to study specific memory processes including memory recall and retrieval cues.

Use in memory research

[1] Hypnotic amnesia, or forgetting under

Overview

Hypnosis and selective amnesia

  • Hypnosis and selective amnesia 1
    • Overview 1.1
    • Use in memory research 1.2
  • Factors of selective amnesia 2
    • Emotional connotations 2.1
    • Familiarity 2.2
    • Types of memory 2.3
    • Serial position 2.4
    • Memory consolidation 2.5
  • Use in treatment 3
  • Selective amnesia in everyday life 4
  • Case studies 5
    • Patient A 5.1
    • Patient B 5.2
  • References 6

Contents

This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
 
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
 
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.
 



Copyright © World Library Foundation. All rights reserved. eBooks from World eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.