L9 Intrusive Thinking Flashcards
Learning Objectives
- Describe some everyday examples of intrusive thinking, and examples of how intrusive thoughts are triggered.
- Describe examples of how intrusions may interfere with everyday life, and how they manifest in different mental disorders
- Describe methods for investigating intrusive thoughts, and elaborate on the pros and cons of each method.
- Describe mechanistic accounts of intrusive thinking, and intrusive memories in particular, and apply them to a case.
in this flashcards
- lecture
- chapter from script of congress where researchers were investigating intrusive thoughts
What is an intrusive thought?
- Classic definition: “any distinct, identifiable, cognitive event that is unwanted, unintended and recurrent. It interrupts the flow of thought, interferes in task performance, is associated with negative affect, and is difficult to control”
- in brief: “conscious, involuntary and unwanted thought”
! this definition does not capture all forms
> e.g. not always negative affect
What are the main features of intrusions? (x11)
(article)
1- Consciousness
> experienced mental events; you are not aware necessarily that is an intrusion, but you are aware that you are having those thoughts
2- Unwantedness/desirability
> not necessarily negative in content, but unwanted in the moment because they distract from task. Not necessarily unwanted (e.g. rumination in depression), so this is still unclear in definition
3- Involuntary/Controllability
> does it mean that they pop in your mind without you deliberately thinking about them (involuntary), or that once they appear, are difficult to ignore or suppress (uncontrollable)? Depends on how broad your definition is
4- Disruptiveness
> interrupts and disrupts current cognition; even if individual does not experience it as intrusive, it’s still maladaptive
5- Salience
> captures attention (vivid, novel, incongruent, aspects, …)
6- Valence
> not necessarily negative (e.g. being in love, feelings of grandeur, insights)
7- Content and Shape
> verbal thoughts, slips of action, mental images; past, present, future (varies)
8- Punctate vs Extended
> appear unexpectedly, last for limited or extended period of time (e.g. rumination, flashbacks). If they last long, they become primary cognitive processes > should it still be considered an intrusion?
9- Recurrence
> frequency and/or recurrent content
10- Trigger
> can come from external and internal cues, but intrusion because it interrupts
11- Agency
> also internal agency
What is a better definition of intrusive thought?
- singular parts explained
- “interruptive, salient, experienced mental events”
> interruptive→ it interrupts the stream of thoughts, task that you’re doing, …
> salient→ needs to draw attention (intense, not neutral)
> experienced mental event→ we need to be conscious
What are the usual contents of the intrusive thoughts?
- past and future emotional events
> e.g. future wedding you’re excited about; future doctor’s appointment you’re worried about, … - unsolved problems/tasks
> e.g. tip-of-tongue feeling of thought; something that you can’t stop thinking about while doing something else - uncertain events
> e.g. did I lock the door? did I turn off the gas? - frequent stimuli
> e.g. earworm (song stuck in your head)
Content of intrusive thoughts in healthy individuals (x8)
(article)
*1- Emotionally salient events
> e.g. traumatic event, first love, …
*2- Incompletions
> when start a process and leave it incomplete, thoughts about it keep coming back until the process is completed
> thoughts might be amplified by salience or emotional intensity of incomplete process
> “tip-of-tongue” sensation (processes still go on in background of our mind, like insight problems)
3- Intentions
> actions that you are postponing; you put them on to-do list, but still pop up in your mind
4- Anticipated events
> especially if they carry both positive and negative emotions (e.g. a friend visiting)
*5- Uncertain events
> about past (e.g. have I locked the door?)
> about future (helps prepare for different outcomes)
6- Dissonant facts, events or beliefs
> e.g. dissonance between action and self-perception
> this discrepacy can lead to intrusions about whether we should change our self-image (cognitive dissonance)
*7- Frequent events, stimuli or ideas
> e.g. a song heard a thousand times will become a ear-worm
> salience, emotionality and dissonance are not necessary
8- Images
> experiences of perception that occur in the absence of external sensory input
> both about past and future
> can be both benign, or set off cascade of disruptive cognitive processes
what forms can the intrusive thoughts have?
- usually they are verbal thoughts
- often, they take form of images
> “representations and the accompanying experience of sensory information without direct external stimulus”
what are the qualities of the intrusive images?
- they can be of many modalities (auditory, feeling, …)
- “Here and Now” quality (it feels real)
> e.g. Proust’s madeleine
> e.g. feeling embarassment when passing through place you once fell - strong link to emotions
the Triggers of intrusive thoughts
+ link to cognitive control
- intrusive thoughts seem to come out of nowhere, but usually they are triggered by associated cues:
> External cues→ sight, sound, smell, words, …
> Internal cues→ mood, physiology, …
!- probability increases with diminished cognitive control
> e.g. sleep loss; drugs; alcohol; …
> you are less able to inhibit control
External and internal triggers (x3)
(article)
1- Cue-driven retrieval
> specific stimuli in the world or concepts in memory
> e.g. hearing a song, seeing someone’s face
2- Matching mood and physiological state
> memories are encoded together with context (e.g. environment, mood, or arousal state
> chance of retrieving memory is higher when one is in specific physiological state
> e.g. events occurring when in angry mood are more easily recalled when again in angry mood
3- Diminished cognitive control
> that would lead for example to less inhibitory control
> e.g. sleep deprivation, general fatigue, stress, lack of exercise, …
> this puts individuals at risk of developing clinical intrusions
the importance of Control in intrusive thinking
- need to control the thought + distress are what define intrusive thoughts
- a spontaneous thought/memory that causes a lot of distress is usually intrusive
> not about the content, but about the moment of intrusion (!)
> content can also be neutral or positive - many situations require you to control your thoughts
Desirability of control
- contexts in everyday life where people are motivated to forget thoughts (x9)
(article)
1- Concentration during tasks
> achieving concentration is adaptive
2- Executing high-performance cognitive and motor skills
> top athletes need to concentrate, and get rid of “chocking under pressure” feeling
3- Regulating pain
> people that went through trauma tolerate pain longer and have less pain catastrophizing
> controlling intrusive thoughts about pain reduces suffering and increases ability to pursue other goals
4- Regulating affect
> intrusions can change the emotions (e.g. you see your ex’es car and become sad)
> by controlling intrusions, we seek emotional homeostasis
5- Persisting in the face of failure
> thoughts about failure are unpleasant and undermine feelings of competence and control
→ abandon goals earlier than they should
> limits personal growth
6- Protecting self-image
> people try to forget embarassing situations/things that undermine own self-confidence
> greater forgetting for negative feedback (in healthy individuals)
> positive self-illusion and forget threats to positive self-image (associated to better mental health)
7- Justifying inappropriate behavior
> dissonance is created between one’s beliefs and deeds
> people forget their own ethical lapses
8- Maintaining attitudes and beliefs
> dissonance between own beliefs (e.g. politics, religion) and contradictory evidence
9- Forgiving others and maintaining attachment
> suppressing intrusive thoughts about anger towards others in order to forgive them (e.g. partner or boss; ameliorates relationships)
The taxonomy of intrusive thoughts
(she said that this is not in the literature but that it is important to know)
(see graph)
1- there are Involuntary autiobiographical memories and Involuntary thoughts
> these are Spontaneous
→ do they interrupt ongoing thought process? / do they interefere with what you were doing?
→ If yes, then…
2. Intrusive memory and Intrusive thought
> these are Interruptive, Salient and/or Distressing
3. Clinical (Obsession - e.g. OCD)
> these are Impairing
4. Flashback (e.g. PTSD)
> Impairing + Nowness
when Proust was eating a madeleine, he got transported back to his childhood
- is this an intrusion?
- what does this show?
- content: positive
- sponaneous thought: ✓
- distressing: ✗
- salient: ✓
- interruptive:
> if yes→ intrusive
> if no→ not intrusive
→ this shows that despite the positive content, if the thought interrupts activities/other thoughts, then it is intrusive
→ she then adds that it is also about the distress; if it is really distressing, the moment does not matter, it is still considered an intrusion
= therefore, an intrusion is characterized by being interrupting and/or distressing
Now, focusing on clinical intrusions
- what distinguishes a clinical vs non-clinical intrusion?
- Negative appraisal of intrusions (“something is wrong with me”) [most important]
Clinical intrusions are also…
- Interrupting
- Distressing (can be from content, but not necessarily)
- Frequency
- Avoidance behavior
wanted intrusions
(article)
Not all intrusions are unwanted - e.g.:
- to dampen present agony (suicidal ideation)
- mentally expose oneself to feared situation in the future (worry)
- cravings (unwanted only when trying to abstain)
Everyday manifestation of intrusive thinking
(article)
- people engage in “mind wandering” 50% of awake time→ is this everyday intrusive thinking?
Mind wandering is…
1- Unwanted
> it disrupts task performance across many cognitively demanding domains (e.g. causes car accidents
> useful for distal tasks (e.g. planning)
= creates problems & contributes to tasks
2- Unintended
> lack of meta-awareness is associated to disruptive mind wandering and about unwanted thoughts
3- Recurrent
> content varies, so whether it is recurrent depends on the level of analysis
4- Associated with Negative Affect
> when mind wandering, less happiness than when on task
> also depends on content
5- Difficulty of Control
> if you think you can’t control it, you do it more often
Negative appraisal
+ Thought-action fusion
- negative appraisal is key characteristic of a clinical intrusion
> e.g. most new parents (~90%) experienced intrusive images, (e.g. the baby suffocating, having an accident, being harmed)
> only those who believe that having such thoughts makes those events more likely to occur show a higher probability of experiencing OCD symptoms later on
→ Thought-action fusion: belief that thinking about something makes it more likely to happen
> this is predictor of OCD
(appraisal of intrusions both pre- and post-trauma are predictive of PTSD development)
Clinical intrusions
Intrusions as Transdiagnostic Symptoms
- high prevalence in clinical samples (transdiagnostic)
- PTSD & Depression→ past events
- other disorders→ fears of future, hypothetical catastrophic outcomes, (or different reality)
> e.g. OCD, panic disorder, health anxiety, social anxiety, eating disorder, bipolar disorder, psychosis
Clinical intrusions
- what are the most prototypical forms of intrusions?
- PTDS→ intrusive memories, flashbacks, …
- OCD→ obsessions, compulsions
> OCD will be talked about more in the next block, now the focus is on PTSD
OCD - DSM-V
- criteria
- Ego-dystonic note
- Obsessions:
> Recurrent, intrusive, persistent, unwanted, urges, or images
> The attempt to ignore, suppress, or neutralize such thoughts, urges, or images - Compulsions:
> Repetitive behaviors or mental actions that a person feels compelled to perform - in response to obsessions or according to rigid rules - to prevent distress or dreaded event
> Acts that are excessively or unlikely to prevent the dreaded situation - The thoughts or activities are time consuming (>1h per day), causing clinically significant distress
! obsessions are often Ego-Dystonic
> e.g. aggressive thoughts about harming children
> e.g. obscene images/impulses in church
> e.g. unacceptable sexual acts
Posttraumatic Stress Disorder
- DSM-V criteria
(A. Exposure to traumatic event)
!! B. Intrusion sumptoms (one or more):
1. Recurrent, involuntary, and intrusive distressing memories of the trauma
2. Recurrent, distressing dreams related to the event(s)
3. Dissociative reactions (e.g. flashbacks) in which the individual feels or acts as if the trauma(s) were recurring
4. Intense or prolonged distress or physiological reactivity in response to reminders of the trauma(s)
5. Marked physiological reactions to internal or external cues that symbolize or resemble an aspect of the traumatic event(s)
(C. Avoidance, negative alterations, …
F. Symptoms start or worsened after trauma, present >1 month)
! called “Re-experiencing” in past DSM versions
Intrusive memories of trauma
- studies + results
- intrusive memories are very common after experiencing a trauma
- there was a huge train crash (Pécrot, Belgium) that was witnessed by a lot of people
> 86% experienced intrusive memories after 3 weeks - In a study of motor vehicle accident patients:
> 76% had intrusive memories in the
first few weeks
> 25% at 3 months
> 24% at 1 year
→ this means that people with intrusive memories after three months, were very likely to have them after one year
Pécrot study - overview of important findings
Is there a significant difference in the following between clinical and non-clinical PTSD patients?
- presence of initial intrusion (no)
- content of intrusions (no)
- presence of other symptoms
Does the initial presence or the frequency of intrusions predict later PTSD?
(Pécrot study)
(see graph)
- on graph you can see % of intrusions in PTSD patients and non-PTSD patients
- there is significant difference at the start as well, but it is not significant enough to predict later PTSD onset at individual level
→ so answer is yes and no
what are some common intrusive memories of trauma?
- what do they involve?
(Pécrot study)
- involve sensory experiences
> sounds (crash, victims)
> visual images (visual remains, victims)
> thoughts (victims, relatives)
does the content of trauma intrusion distinguish clinical vs non-clinical intrusions?
(Pécrot study)
(see graph)
- 50% of participants presented sensory experiences only, both in PTSD and no PTSD patients
→ this shows that content of intrusions does not distinguish between clinical and non-clinical intrusions
What other symptoms did intrusions lead to?
(Pécrot study)
+ Avoidance
- distress (66%)
- cognitive avoidance (66%)
- hypervigilance (62%)
→ intrusions usually lead to other symptoms as well
Avoidance
(see graph)
- at 1 week→ no one was avoiding memories of trauma (yet)
- at 6 months→ big avoidance in PTSD people, but just little avoidance in no-PTSD people
what do the cognitive models of PTSD say?
(Pécrot study)
- intrusive memories of trauma are at the core of all symptoms
- they are the driver of the three other symptoms clusters: avoidance, negative alterations in cognition and mood, hyperarousal
- in turn, avoidance maintains symptoms
> e.g. if no exposure→ no new neutral associations
Less prototypical forms of intrusive thinking
(+ article)
We talked about the most common types (PTSD and OCD) already, but there are intrusions in other disorders as well:
-
Substance use disorder (craving)
> can happen at different stages of the addition, and it can come from internal and external cues. It’s the first cause leading to drug taking and relapse. Becomes more of an intrusion in later stages. -
Mood disorders (rumination, flash forward)
> rumination, sucidal thoughts, negative automatic thoughts (on negative schemata) and flight of ideas (mania). Rumination usually on the cause of distress, shortcomings, failures and mistakes. -
Anxiety (worry, future)
> for anxious arousal, the intrusive thoughts concern e.g. panic attacks, phobic object, …
> for anxious apprehension, intrusive thoughts are related to future events (intolerance of uncertainty) - Bipolar disorder (flash forward)
-
Psychosis (hallucinations, thought insertions)
> thought insertion (e.g.) are salient, interruptive and unwanted, but attributed to outside agent, and delusional people do not perceive them as interruptive -
ADHD (impulsive action, inattention, mind wandering)
> are distracting internal thoughts intrusions? (disruptive and maladaptive, but not unwanted and default)
(for Psychosis and Attention deficit disorder, the rules on whether the above are considered clinical are less clear)
Measuring Intrusions
- what are the challenges?
- looking at physiological response
→ what is the causal direction? - how do we invoke spontaneous thoughts?
> most times, we don’t know the triggers - self report
→ people don’t remember their own intrusions
→ people would need to know exact definition of intrusion
→ people migh lie because of shame (e.g. of content), or distress (traumatic content)
= hard to study the timing of the intrusions
Overview
Research paradigms & putative mechanisms
- Experience sampling
- Trauma Film Paradigm → single vs dual trace
- Think/ No think paradigm → (deficit in) cognitive control
- Memory processing
- Pavlovian conditioning → e.g. Contemporary Learning Theory
Experience sampling
(way to sample intrusions)
(see picture)
- invoking intrusions in lab by letting participants do very poor tasks
> e.g. having to press button when seeing number 3, for 20 min
- this is a very boring task, and participants get distracted
- people asked to report distractions and intrusions
> either they stop the task every time they have an intrusion and write it down
> or researchers stop task every few minutes and ask participants what they are thinking about
= shows that having an experience and knowing that you’re having an experience are different things
what are the pros and cons of experience sampling?
Pros:
- both naturally occurring intrusions and intrusions cued by peculiar prompts
- translation from lab to real-life
Cons:
- Requires meta-awareness (the participants need to be aware of when they are having an intrusion)
> hard to realize, if doing a boring task (awareness usually after 30s)
> can be compromised in clinical populations
- non clinical participants don’t really know what an intrusion is
> i.e. without a clear event or cue to induce intrusions
- No control over event, peri-event factors (for intrusions relating to past events)
> e.g. for something happened in the past, we can only rely on participant’s memory and report
- No control over timing of intrusion
> no precise report of timing of intrusion
- Involuntariness difficult to verify
> e.g. to some degree, worry is voluntary
How can we study triggers of intrusions?
- intrusions are often images of the worst moment of the trauma
- knowing how they arise and persist may point at targets for treatment
→ to study this, we want to manipulate event itself (memory research)
Multi-store Memory Model
+ related research questions
(see graph)
- Atkinson & Shiffrin
- sensory input→ sensory memory→ attention→ short-term memory (+ maintenance reharsal)→ encoding→ long-term memory (+retrieval→ short-term m.)
Research questions
- what is it about stimulus that makes something intrusive?
- does it have to be long, hard, unexpected, physically endangering, … ?
- how does attention change when consuming lots of alcohol?
- what happens during and shortly after event that makes certain memories engrained in brain?
> Single and Dual Trace theory
How are traumatic memories encoded and retrieved in autiobiographical memory?
- Single Trace Theory
- (memory is stronger)
- enhanced memory activation
→ this creates noradrenaline
→ this consolidates memory better in long-term memory
→ better memory is more accessible
→ more intrusive and distressing recollections
= emotional intensity strengthens memory consolidation making memory much more accessible
= emotional memories are simply stronger memories, making them more accessible and easily triggered
What is the evidence for the single trace theory?
(article)
Emotional memories are…
- typically vivid
- often particularly resistant to the passive processes that usually lead memories to be forgotten over time
How are traumatic memories encoded and retrieved in autiobiographical memory?
- Dual Trace Theory
- memory is not stronger, but less contextualized and more fragmented (more selective)
- overwhelming stress
→ over-consolidation of perceptual elements
→ this impairs integration with contextual fears in autiobiographical memories
> (not integrated in whole story line, context is not consolidated)
> we can’t recall where, when, how it happened
→ more fragmented memory
→ traumatic recollections feel as if they were happening in the present (e.g. PTSD)
= stress disrupts proper memory integration, making the trauma feel ever-present
what is evidence in favor of the dual trace theory?
(article)
- the intrusiveness of a memory can be selectively reduced while leaving the voluntary recall of a memory intact (and vice versa)
- these types of memories might rely on distinct systems or at least distinct representations
Trauma film paradigm + diary
- method used in research to study how people repond to traumatic experiences (memories and intrusions)
- participants shown distressing film clips
- in the following week, participants keep a diary of any intrusive memories regarding film clips
- after 1 week, participants took a test of vulontary memory
→ helps us test voluntary and involuntary memory
How can control processes limit encoding and consolidation of intrusive memories?
(article)
- engaging in a competing visuospatial task, during or shortly after experiencing an event, can reduce the frequency of intrusions of that
event over the subsequent week - when people are instructed to forget the immediately preceding memory item in a list, the instruction has a large impact on later retention of the memory, rendering to-be-forgotten items signifi cantly less accessible, even for emotionally unpleasant scenes
= participants can successfully block the encoding of recent events into long-term memory when motivated to do so
What are the Pros of the trauma film paradigm?
Pros
1- Controlled environment
> researchers can control the type of trauma shown and factors around it
2- Reliable memory testing
> “golden standard” for accuracy of memory
> allows comparison to measures of voluntary recall
> since everyone sees the same film, researchers can accurately measure how well memories are formed and recalled
3- Relatively high ecological validity
> compared to pictures, conditioning, …
> watching a film is more like real-life experiences
What are the Cons of the trauma film paradigm?
1- Requires meta-awareness
2- Film only a proxy for trauma, not autiobiographical
> it’s not a real trauma and you are only a witness
> much more effective if you are actor in situation
3- No control over timing of intrusions
> form of real-life experience sampling
4- Involuntariness difficult to verify
5- Ethical? Informed consent, proper screening, and if necessary, after care!
Irish clip on car crush
- what can we learn from this?
- wear a seat belt
- the “hotspot” can be anything, from the glass shattering, any sentence said before the crush, the blood, the screams, seeing someone being couply in cars, the honking, …
- when asking people that experienced a traumatic event, often they are not able to report events cronologically
> as the perceptual memories are very strong but not integrated with the context of the trauma
(she didn’t say that one model is better than the other, she just connected the fragments one to this clip)
Cognitive models of PTSD
- how do intrusions arise?
(this is the cognitive take on how traumatic memories are encoded and consolidated)
- Poorly processed trauma memory
> fragmented and disorganized
- Strong perceptual priming
> sensory based fragments (unconstrained by context) are activated by stimuli that resemble elements of the hotspot, or that were persent around the time of the hotspot
> the context helps us place the memory in the past, but if it’s not complete, then the memory might come back as present
Think/No think paradigm
- if Film Paradigm focuses on the encoding, the Think/no think Paradigm focuses on the retrieval processes
- “how well are you able to suppress thoughts at a later time point?”
Think/No think Paradigm
(see picture)
- all participants study associations between words and images
- in second phase, the words would come back either in red or green, without the image
> if word in green→ participants had to recall image
> if word in red→ participants had to inhibit image
Think/No think Paradigm - results
- if actively suppressed memory, there is worse recall afterwards, even when asked to try to remember image
- active suppression has lasting effect
- “amnesic shadow” surrounds images that were once actively suppressed
- suppression-induced forgetting → increases with the number of times that people suppress the unwanted content
> if try to recall image in another context to the one of experiment, memory might be a bit more easily recalled
Suppression-induced forgetting
(article)
- not only for simple pairs, but also for objects or complex scenes
- irrespective of whether neutral or negatively valenced
- influences both explicit and implicit memories
- reduction in affective responses to the suppressed content when participants see it later
= retrieval suppression (healthy p.) regulates the negative affect associated with intrusive memories - linked to lower rumination, greater thought control, fewer intrusive memories
> psychiatric populations struggle with cognitive control (→ difficulty in suppressing)
What are the pros of the Think/No think paradigm?
1- Environment control
> control over event and ‘peri-trauma’ factors
2- Accurate memory testing
> ’golden standard’ for accuracy of memory, which allows comparison to measures of voluntary recall
3- Control over timing of intrusion (ideal for concurrent neural/ physiological assessments)
4- Clear inference of involuntariness
> since participants were asked not to think about it, any intrusion is clear evidence of involuntary thought
> intrusions occur about 30% of no-think trials, providing a clear, measurable way to assess how vulnerable someone is to unwanted thoughts
What are the Cons of Think/No think paradigm?
1- Requires meta-awareness
2- Demand bias? (participants are instructed to suppress)
3- Low ecological validity
Cognitive control for retrieval suppression
(this is the cognitive take on how traumatic memories are recalled)
- poor cognitive control leads to involuntary retrievals of past and imagined events
- insufficient inhibition of hippocampus and amygdala
- lack of sleep and pre-existing conditions can worsen this, creating a vicious cycle
(see pictures)
trauma→ no cognitive control→ daily problems→ no cognitive control→ …
Is suppression maladaptive?
(article)
- many clinicians would say that it is (might lead to psychiatric disorders
- however, there is evidence that suppresssion is natural and evolutionary:
1. Functional purpose of concentrating on task and suppressing distractions
2. to achieve emotional balance after upsetting event we need to “get over” unwelcome thoughts
3. after trauma, in healthy individuals intrusive memories should diminish over time (natural to reduce them)
4. people that cannot discard anxious thoughts about future events are “less healthy”
5. controlling cognition and behavior is not only desirable but an essential capacity of intelligence
what are the difficulties with using White Bear suppression as model for controlling intrusions?
(article)
- The task is self-defeating because it requires one to violate the task’s goals to check whether the goal is being accomplished
- the White Bear Suppression Inventory measures both thought suppression frequency and experience of intrusiveness (only the latter correlates with clinical symptoms)
- this task shows non significant differences between control and clinical participants (not valid)
- patients have difficulties applying inhibitory control (rather than bysuppression being intrinsically maladaptive)
= suppression is healthy coping response that, when disordered, poses risk factor in developing intrusive symptoms
The problems with the definition of suppression
(lecture + article)
Retrieval suppression has been mistakenly equated to:
- White bear suppression
> the task asks to suppress a specific thought, which creates a paradox because we need to remember not to think about the white bear, making us thinking about it
→ in retrieval suppression, there is no specific content to be inhibited, we just rather have to suppress whatever is associated to the reminder
-
Expressive suppression
> inhibit behaviors associated with emotional states (you have retrieved the memory but you try to suppress the expression of the emotion - “poker face”)
> involves motor control (not control over thoughts or feelings)
→ in retrieval suppression, we suppress mnemonic processes and content - (cognitive) Avoidance of reminders
> entirely avoiding reminders that could trigger unwanted thoughts or emotions
> not confronting triggers → preserved without alterations (maladaptive process - “not dealing with problems”)
→ in retrieval suppression, you don’t avoid reminders, you confront them directly and suppress whatever is associated to them - (General) Distraction
> removal of attention from emotions/thoughts and refocusing it onto other unrelated stimuli
~ General distraction: attention shifts to stimuli unrelated to the intruding thoughts
~ Specific distraction: interacting with reminders
> general distraction functions as avoidance, while specific distraction functions as thought substitution (generating alternative associations in response to reminder)
→ general distraction ≠ retrieval suppression
Why do we have intrusions?
- process salient experiences
> you are confronted with images until brain deals with them - opportunity to update the memory
> e.g. through reconsolidation, integration, extinction, … - to guide future behaviors (warning signal, survival)
> remembering past catastrophes
> simulating future scenarios to assess dangers
(see graph)
(not sure, these are just hypotheses)
Remember? Extinction vs reconsolidation
- Extinction: repeated presentation of a conditioned stimulus leads to the progressive decrease in behavioral expression of a memory
- Reconsolidation: the presentation of an isolated retrieval initiates molecular cascades that can be bidirectionally modulated to either strengthen or weaken memory trace
! intrusive memories might be resistant to modification (we need more research)
(here the article re-explained how reconsolidation works)
Retrieval-induced forgetting
(article)
- Retrieval Competition: stimuli are often associated to multiple different memories, and the brain must choose the correct memory among many competing traces
> Retrieval Interference: competition between memories - to successfully retrieve desired memory, the brain must suppress competing memories, but this leads to the suppressed memories being harder to recall later
- Retrieval-induced forgetting: the act of remembering something can cause the forgetting of other related memories (that were suppressed during the retrieval)
the role of retrieval-induced forgetting in clinical settings
+ thought substitution
(article)
- might be crucial to reduce the accessibility of negative interpretations and intrusions (via choosing to remember positive events)
- Thought Substitution: participants instructed to stop retrieval of unwanted memory by retrieving different content
Retrieval-practice paradigm
- participants learn to associate cue with multiple associates
> then asked to retrieve subset of the items, but not the rest - focuses on thought substitution, not thought suppression (like think-no think paradigm)
! allows us to understand memory inhibition mechanisms, both at neural level and foundational neurobiological level
Tetris - memory updating
- tetris, emdr, … have been proven successful to update memories, when they are in the active (labile) state
- interfering with vividness of image itself (you are not unlearning the memory)
(see picture)
Classical Conditioning
+ Odor study
- some say that intrusive memories are conditioned response
> e.g. intrusions can be other reaction to conditioned stimulus (together with sweating, startle reflex, pupil dialation, …)
Odor-evoked intrusions
- unfamiliar odour paired with a specific adverse event (distressing film) triggers memories of that event one week later, but not other events encoded in close temporal proximity
→ intrusive memories have very clear cues specificity
intrusive traumatic memory = conditioned response?
- Neutral stimulus (CS) triggers intrusions of aversive outcome (US)
- when intrusions are excessive or fail to extinguish → clinical
- there is some lab evidence
→ however, difficult to identify what is a CS and what is a US in real-life events
