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A proposed clinical-neuroscience framework of intrusive memories breaking intrusive memories into five component parts.
Source publication
This hypothesis and theory paper presents a pragmatic framework to help bridge the clinical presentation and neuroscience of intrusive memories following psychological trauma. Intrusive memories are a hallmark symptom of post-traumatic stress disorder (PTSD). However, key questions, including those involving etiology, remain. In particular, we know...
Citations
... This reliving may distinguish TR-IMs from other forms of episodic memory and contributes to their dissociative counterpart -flashbacksin posttraumatic stress disorder (PTSD) [8,9]. Additionally, IMs exhibit distinct cognitive-affective properties, such as significant emotional distress and "attentional hijacking" [10,11]. Various conceptual models of TR-IMs have emerged from these phenomenological properties, especially in relation to PTSD. ...
Trauma-related intrusive memories (TR-IMs) possess unique phenomenological properties that contribute to adverse post-traumatic outcomes, positioning them as critical intervention targets. However, transdiagnostic treatments for TR-IMs are scarce, as their underlying mechanisms have been investigated separate from their unique phenomenological properties. Extant models of more general episodic memory highlight dynamic hippocampal-cortical interactions that vary along the anterior-posterior axis of the hippocampus (HPC) to support different cognitive-affective and sensory-perceptual features of memory. Extending this work into the unique properties of TR-IMs, we conducted a study of eighty-four trauma-exposed adults who completed daily ecological momentary assessments of TR-IM properties followed by resting-state functional magnetic resonance imaging (rs-fMRI). Spatiotemporal dynamics of anterior and posterior hippocampal (a/pHPC)-cortical networks were assessed using co-activation pattern analysis to investigate their associations with different properties of TR-IMs. Emotional intensity of TR-IMs was inversely associated with the frequency and persistence of an aHPC-default mode network co-activation pattern. Conversely, sensory features of TR-IMs were associated with more frequent co-activation of the HPC with sensory cortices and the ventral attention network, and the reliving of TR-IMs in the “here-and-now” was associated with more persistent co-activation of the pHPC and the visual cortex. Notably, no associations were found between HPC-cortical network dynamics and conventional symptom measures, including TR-IM frequency or retrospective recall, underscoring the utility of ecological assessments of memory properties in identifying their neural substrates. These findings provide novel insights into the neural correlates of the unique features of TR-IMs that are critical for the development of individualized, transdiagnostic treatments for this pervasive, difficult-to-treat symptom.
... Previous studies have shown that the higher levels of vividness in negative mental imagery are associated with greater distress [35,37]. Intensely vivid mental imagery is prevalent across a spectrum of psychopathologies, encompassing anxiety disorders [38], post-traumatic stress disorder [39], schizophrenia [32], and substance use disorder [40]. Alexithymia has also been associated with challenges in affect-related mentalization [41]. ...
This study aims to explore the mediating role of mental imagery in the relationship between alexithymia and parental psychological control among Chinese university students. Conducted between March and April 2023, this descriptive study involved 282 volunteer participants from a university in southern China. Data collection included the Toronto Alexithymia Scale (TAS), the Parental Psychological Control Scale (PPC), and the Vividness of Visual Mental Imagery questionnaire (VVIQ). The results revealed that: (1) based on established cut-off, 81 students were identified as highly alexithymic; (2) the alexithymia group scored higher on both the TAS and PPC and lower on the VVIQ compared to the non-alexithymia and possible-alexithymia groups; and (3) mediating analysis demonstrated a strong and positive correlation between parental psychological control and alexithymia for all participants, with visual mental imagery mediating this relationship. This study underscores the interconnectedness of parental psychological control, visual mental imagery, and alexithymia among college students. The theoretical and clinical implications of these findings are also discussed.
... Vividness refers to the clarity with which an individual subjectively perceives a mental image (Sutin and Robins, 2007). Highly vivid MI are ubiquitous in psychopathology and contribute to the psychological suffering of individuals (Clark and Mackay, 2015;Connor et al., 2014;Hirsch and Holmes, 2007;Pearson et al., 2015). This also applies to behaviours such as food cravings (Kemps and Tiggemann, 2015) and suicidality (Ng et al., 2016). ...
Background
Mental imagery, or ‘seeing with the mind’s eye’ (Kosslyn et al . 2001), provokes strong emotional responses (Ji et al ., 2016). To date, there is a lack of data on the content and clinical characteristics (e.g. vividness, likelihood, emotional effects) of spontaneous mental images (MI) in people with bipolar disorder (BD) according to their thymic states.
Aim
The current study sought to assess the characteristics associated with the contents of MI in people with BD.
Method
Forty-two euthymic individuals diagnosed with BD (American Psychiatric Association, 2013) were asked to self-report their MI during depression, (hypo)mania and euthymia. Participants also rated levels of vividness, likelihood and emotional activation related to MI (i.e. valence, arousal, type of emotion).
Results
The contents of the MI revealed phenomenological aspects of BD. Different themes were associated with each thymic phase. In (hypo)mania and in euthymia, the mental images were assessed as being as vivid as probable ( p >.05). (Hypo)manic and euthymic-related MI activated more pleasure than displeasure ( p <.001) and were mainly associated with joy. In depression, MI were assessed as more vivid than likely ( p <.05). In depression, MI activated more displeasure than pleasure ( p <.0001) and induced mainly sadness.
Discussion
Overall, a congruence between the contents of images and the three thymic phases was found. The content of the MI was related to self-reported emotional effects that were congruent with the thymic phases concerned. The results add new clinical information for the use of imagery-based cognitive therapy in individuals with BD.
... In this approach, participants view film clips depicting negative events in a laboratory setting and complete a week-long intrusion diary (Holmes & Bourne, 2008;Holmes et al., 2004). Studies using the trauma film paradigm have identified that individuals with heightened trait anxiety are more likely to experience intrusions following negative events (Clark & Mackay, 2015;Laposa & Alden, 2008;Logan & O'Kearney, 2012;Regambal & Alden, 2009). Trait anxiety refers to a stable dispositional characteristic reflecting the degree to which an individual will experience an elevated anxious mood in response to an environmental stressor (Endler, 1997). ...
... The results of the current study also demonstrated that attentional bias to negative information observed at longer stimulus exposure duration (ABNII1000), mediated the relationship between heightened trait anxiety and elevated intrusion frequency. The present finding is consistent with previous research that has demonstrated an association between attentional bias and intrusion frequency (Clark & Mackay, 2015;Laposa & Alden, 2008;Logan & O'Kearney, 2012;Regambal & Alden, 2009). While the results of the present experiment are statistically significant, it should be noted that the amount magnitude of this effect is very small. ...
Background and objectives:
Research shows that individuals with heightened trait anxiety are more likely to experience intrusions; however, the mechanism that accounts for this relationship is unclear. Two alternative hypotheses were tested to determine the nature of the associations between trait anxiety, attentional bias to negative information, and intrusion vulnerability.
Methods:
Intrusions were elicited using the trauma film paradigm, and post-event attentional bias to negative information was assessed using the dot-probe task. Participants then completed a week-long intrusions diary.
Results:
Results showed that attentional bias to negative information mediated the effect of heightened trait anxiety on elevated intrusion frequency. It was also revealed that heightened trait anxiety was associated with elevated intrusion-related distress, though attentional bias to negative information did not mediate this relationship.
Limitations:
Our sample was comprised of undergraduate students who were not selected based on a previous pathology. Replication in clinical samples is warranted.
Conclusions:
These findings provide new insight regarding individual differences in the experience of intrusions and suggest that both the frequency and distress associated with intrusions could represent clinical targets.
... Unlike in PTSD, symptoms emerging after an experimental trauma only last for hours to days and decline within 1 week (Holmes et al., 2004;James et al., 2016). In sum, the trauma film paradigm provides an ideal setting to bridge clinical and nonclinical samples in a highly controlled setting to examine the development of PTSD symptoms (Clark & Mackay, 2015). ...
Recent findings indicate that sleep after trauma compared to sleep loss inhibits intrusive memory development, possibly by promoting adequate memory consolidation and integration. However, the underlying neural mechanisms are still unknown. Here, we examined the neural correlates underlying the effects of sleep on traumatic memory development in 110 healthy participants using a trauma film paradigm and an implicit memory task with fMRI recordings in a between-subjects design. To further facilitate memory integration, we used targeted memory reactivation (TMR) to reactivate traumatic memories during sleep. We found that sleep (i.e., nap) compared to wakefulness reduced the number of intrusive traumatic memories for the experimental trauma groups. TMR during sleep only descriptively reduced the intrusions further. On the level of brain activity, increased activity in the anterior and posterior cingulate cortex, retrosplenial cortex and precuneus was found in the experimental trauma group compared to the control group after wakefulness. After sleep, on the other hand, these findings could not be found in the experimental trauma groups compared to the control group. Sleep compared to wakefulness increased activity in the cerebellum, fusiform gyrus, inferior temporal lobe, hippocampus, and amygdala during implicit retrieval of trauma memories in the experimental trauma groups. Activity in the hippocampus and the amygdala predicted subsequent intrusions. Results demonstrate the beneficial behavioral and neural effects of sleep after experimental trauma and provide indications for early neural predictor factors. This study has implications for understanding the important role of sleep for personalized treatment and prevention in posttraumatic stress disorder.
... On their own, intrusive memories can cause clinical levels of distress or impairment (Iyadurai et al. 2019). Intrusive memories are known to impact cognitive functioning, especially attention and concentration (Clark and Mackay 2015;Holmes and Mathews 2010 ). They are a core component of trauma-related disorders such as PTSD (American Psychiatric Association 2013) and are prominent across many disorders, including SUD (Brewin et al. 2010). ...
Substance use disorders (SUD) represent a pervasive and ongoing public health crisis responsible for many deaths and hospitalizations each year. Despite decades of research, we have yet to develop an effective cross-substance treatment model. Many who seek and enter treatment for SUD end up relapsing despite their intentions. Inconsistency in treatment success necessitates the identification of novel, universal therapeutic targets in the underlying core mechanisms of SUD. Determining the cognitive mechanisms which promote addictive behaviors is an essential first step to fully understand relapse and maintenance in SUD. The goal of the current review is to explore underlying cognitive processes which prolong SUD despite treatment. Through this, we propose a mechanistic model for how intrusive cognitions may jeopardize symptom improvement and SUD treatment success via risky decision making. Intrusive cognitions - images, words, memories, or impulses - demand little cognitive effort, and lend themselves to quick action and decisions. In the current paper, we present evidence which shows how intrusive cognitions, poorly inhibited, could impair the decision making process in SUD and lead to subsequent addictive behaviors.
... Intrusive memories are targeted in post-traumatic stress disorder (PTSD) through imagery based techniques such as imaginal exposure or imagery rescripting (Clark and Mackay, 2015). Treatment of intrusions via imagery rescripting has gained momentum in recent years, due to findings that this technique has the capacity to modify non-fear-related emotions such as shame, guilt or anger (Dibbets and Arntz, 2016). ...
Intrusive autobiographical memories are a prominent feature of depression implicated in the onset and course of the disorder. Current cognitive behavioural treatment of depression does not specify techniques to address intrusive memories. Imagery rescripting has been demonstrated to be effective in the treatment of trauma-related intrusive memories. This paper illustrates the application of imagery rescripting as a stand-alone treatment for two patients experiencing a current major depressive episode. The two cases are described in detail and follow-up data are reported. Both patients experienced clinically significant and reliable change in their depression scores and no longer met criteria for a current major depressive episode at post-assessment, with gains maintained at 3-month follow-up. Implications are discussed for the theoretical mechanisms of change of this intervention as well as methods to overcome common treatment obstacles that arise in depression.
Key learning aims
(1) To learn how intrusive autobiographical memories are implicated in the onset and maintenance of depression.
(2) To learn the limitations that may present clinically when applying verbal-linguistic techniques such as cognitive restructuring to intrusive memories.
(3) To learn when imagery rescripting may be required to treat intrusive memories and how to implement this technique to overcome traditional treatment obstacles in depression.
... Distressing episodes of our life sometimes hijack our current focus of attention, disrupting cognitive or emotional goals. 1 When these sensory images abruptly and involuntarily penetrate our consciousness, the brain can prevent their retrieval using inhibitory control. [2][3][4] This process often results in a form of active forgetting, reducing the long-term accessibility of unwanted memory traces. ...
Intrusive memories hijack consciousness and their control may lead to forgetting. However, the contribution of reflexive attention to qualifying a memory signal as interfering is unknown. We used machine learning to decode the brain's electrical activity and pinpoint the otherwise hidden emergence of intrusive memories reported during a memory suppression task. Importantly, the algorithm was trained on an independent attentional model of visual activity, mimicking either the abrupt and interfering appearance of visual scenes into conscious awareness or their deliberate exploration. We could generalize the decoding of intrusion into conscious awareness and the decoding accuracy increased when the algorithm was trained using a model of reflexive attention. Conscious detection of intrusive activity decoded from the brain signal was central to the future silencing of suppressed memories and later forgetting. Unwanted memories require the reflexive orienting of attention and access to consciousness to be suppressed effectively by inhibitory control.
... Cortical volumes of interest (VOI's) investigation included frontal and temporal cortices, brain regions typically associated with cognitive domains such as learning, memory, executive functions, and information processing speed 12-16 ; limbic system (including the hippocampus, amygdala, parahippocampal regions including the entorhinal cortex), brain regions typically associated with processing and consolidation of traumatic, and stressful memories 17,18 ; and the occipital lobes, brain regions typically associated with reexperiencing of traumatic memories through mental imagery, states of depersonalization, and dissociation. [19][20][21] Magnetic Resonance Imaging Neurodegeneration Analysis Quantitative volumetric analysis of cortical gray matter volumes was performed utilizing the T1 MPRAGE scans and NeuroQuant (CorTechs Labs, Inc, San Diego, CA), a Food and Drug Administration (FDA) approved software package for automatic labeling, visualization, and volumetric quantification of structural brain VOI's (as percentage of total intracranial volume) which then compares them to an age-and sex-matched normative cohort, generating a brain atrophy report of the responders' volumetric percentiles as compared with norms. 22 We compiled bilateral volumetric percentile data from the 12 study participants and set the cut-off for identifying VOI neurodegeneration at the 5th percentile for age, as per NeuroQuant guidelines. ...
... A relatively unusual hippocampal-sparing form of AD has been reported to occur at a younger age which may apply to WTC responders now at midlife presenting with earlyonset MCI or CI, as this early-onset form of AD is marked by a more pronounced longitudinal cognitive decline and a shorter disease duration as well as earlier mortality. [33][34][35] Moreover, half of these 12 WTC responders displayed neurodegeneration and high FTP retention in the occipital lobe which has been associated with visual hallucinations in AD as a result of atrophy 36 and is a region typically affected in advanced AD. 37 The occipital lobes and/or occipitoparietal border zones are involved in posterior cortical atrophy, 38 as well as in PTSD patients, 39 the latter possibly related to recurring visual "flashbacks" of mental imagery from chronically reexperiencing traumatic events [19][20][21]40 which may pertain to those experienced by WTC responders at September 11, 2001. Recent evidence has linked such PTSD states with underlying neuroinflammation, 41,42 leading to subsequent neurodegeneration, 36,37,39,43,44 thereby warranting a closer investigation and monitoring of WTC responder PTSD symptomatology as a possible contributor to the observed neurocognitive dysfunction which was recently suggested in one of our studies. ...
Purpose Incidence of early onset neurocognitive dysfunction has been reported in World Trade Center (WTC) responders. Ongoing studies are investigating the underlying etiology, as we are concerned that an underlying risk of neurodegenerative dementia may be occurring because of their stressful and neurotoxic exposures to particulate matter when they responded to the search and rescue efforts on September 11, 2001. The purpose of this study is to report preliminary results from two ongoing positron emission tomography (PET)/magnetic resonance imaging (MRI) imaging studies investigating the presence of Alzheimer's disease (AD) biomarkers, such as β-amyloid, tau, and neurodegeneration, and compare our findings to published norms.
Methods We present findings on 12 WTC responders diagnosed with either cognitive impairment (CI) or mild cognitive impairment (MCI), now at midlife, who underwent PET/MRI brain imaging as part of ongoing studies. Six responders with CI received [18F] florbetaben (FBB) to detect β-amyloidosis and six separate responders with MCI received [18F] flortaucipir (FTP) to detect tauopathy. All 12 responders underwent concomitant MRI scans for gray matter volume analysis of neurodegeneration.
Results PET analysis revealed 50% FBB and 50% of FTP scans were clinically read as positive and that 50% of FTP scans identified as consistent with Braak's stage I or II. Furthermore, one responder identified as centiloid positive for AD. Gray matter volumes from MRI analyses were compared with age/sex-matched norms (Neuroquant), identifying abnormally low cortical volumes in the occipital and temporal lobes, as well as the inferior temporal gyri and the entorhinal cortex.
Conclusion These preliminary results suggest that WTC responders with neurocognitive dysfunction may be at increased risk for a neurodegenerative dementia process as a result of their exposures at September 11, 2001.
... Some recent studies identified brain activation patterns during encoding and early retrieval, which appear to be specific to memories that later become intrusive (Clark & Mackay, 2015). In one study, overactivation of cortical brain regions subserving memory formation (left inferior frontal gyrus and bilateral middle temporal gyrus) during the encoding of scenes that later became intrusive versus scenes that were equally graphic but did not become intrusive were observed (Bourne et al., 2013;Clark et al., 2016; see also Clark et al., 2014, for an alternative analysis of the same data). ...
Background: Posttraumatic stress disorder (PTSD) is a debilitating illness associated with distressing symptoms and a high societal burden. Objective: To investigate the neurobiological underpinnings of PTSD to improve our understanding of this disorder and its treatment. Methods: This article reviews currently researched mechanisms that can explain the development of PTSD symptoms. It presents key findings on neural (i. e., brain functioning and brain structure), neuroendocrine (i. e., noradrenergic and hypothalamic-pituitary-adrenal axis activity), and related (epi)genetic changes in individuals with PTSD. Furthermore, it presents preliminary research examining the reversibility of these alterations during psychotherapeutic treatment. Results: PTSD is characterized by specific neurobiological alterations, with preliminary findings indicating that at least some of these may normalize during psychotherapy. Discussion: A multidimensional perspective on the development, maintenance, and treatment of PTSD has the potential to improve our understanding of the causal processes underlying the disorder and may ultimately inform the conception of novel treatments.
