Mapping autobiographical memory in schizophrenia: Clinical implications

Self-concept and Narrative Identity in Youth at Clinical High Risk for Psychosis

BACKGROUND AND HYPOTHESIS

Disturbances of the narrative self and personal identity accompany the onset of psychotic disorders in late adolescence and early adulthood (a formative developmental stage for self-concept and personal narratives). However, these issues have primarily been studied retrospectively after illness onset, limiting any inferences about their developmental course.

STUDY DESIGN

Youth at clinical high risk for psychosis (CHR) (n = 49) and matched healthy comparison youth (n = 52) completed a life story interview (including self-defining memory, turning point, life challenge, and psychotic-like experience) and questionnaires assessing self-esteem, self-beliefs, self-concept clarity, and ruminative/reflective self-focus. Trained raters coded interviews for narrative identity themes of emotional tone, agency, temporal coherence, context coherence, self-event connections, and meaning-making (intraclass correlations >0.75). Statistical analyses tested group differences and relationships between self-concept, narrative identity, symptoms, and functioning.

STUDY RESULTS

CHR participants reported more negative self-esteem and self-beliefs, poorer self-concept clarity, and more ruminative self-focus, all of which related to negative symptoms. CHR participants narrated their life stories with themes of negative emotion and passivity (ie, lack of personal agency), which related to positive and negative symptoms. Reflective self-focus and autobiographical reasoning were unaffected and correlated. Autobiographical reasoning was uniquely associated with preserved role functioning.

CONCLUSIONS

This group of youth at CHR exhibited some, but not all, changes to self-concept and narrative identity seen in psychotic disorders. A core theme of negativity, uncertainty, and passivity ran through their semantic and narrative self-representations. Preserved self-reflection and autobiographical reasoning suggest sources of resilience and potential footholds for cognitive-behavioral and metacognitive interventions.

The positive dimension of schizotypy is associated with self-report measures of autobiographical memory and future thinking but not experimenter-scored indices

ABSTRACTThe ability to remember our past and to imagine the future are critical to our sense of self. Previous research has indicated that they are disrupted in schizophrenia. However, it is unclear (i) whether this is found when examining experimenter-scored indices of content and/or participants' self-report of phenomenological characteristics, and (ii) how these abilities might be related to symptoms. This study sought to address these questions by taking a dimensional approach and measuring positive and negative schizotypal experiences in healthy people (n = 90). Participants were given cue words. For some, they remembered an event from the past and for others they generated an event in the future. No significant relationships were found with any aspect of schizotypy when participants' descriptions were scored by the experimenter according to a standardised episodic content measure. In contrast, several significant positive correlations were observed for past memory and future thinking when examining the positive dimension of schizotypy and participants' ratings, particularly to sensory characteristics of the experience and mental pre- or reliving. These results indicate enhanced subjective experiences of autobiographical memory and future thinking in those who report delusional and hallucinatory-like occurrences, which might be linked to mental imagery or metacognitive alterations.

Improving autobiographical memory in schizophrenia using wearable cameras: A single-case experimental study

Autobiographical memory (AM) impairments influence both sense of identity and social functioning of patients with schizophrenia. However, cognitive remediation methods addressing these difficulties do not sufficiently consider the heterogeneity of this disorder and frequently face methodological limitations. The aim of the present study was to evaluate the efficacy of a method using a wearable camera (NarrativeClip®), through an alternating treatments design across two types of AM training. In parallel, repeated measures were used to appreciate the efficacy, specificity, and generalizability of the programme's benefits. Three patients were invited to wear the camera during 24 personal events. Ten of these events memories were trained by visual cueing (wearable camera condition), 10 others by verbal cueing (written diary condition) and 4 were not trained (control condition). Using pictures collected by the wearable camera seemed particularly relevant, since it promoted more detailed recalls than the diary method, from the first training session and until the end of a one-year follow-up. In addition, the repeated measures performed revealed (1) the efficacy (improvement in AM capacities after participating in the programme), (2) specificity (persistence of working memory deficits), and (3) generalizability (improvement in measures of episodic memory) of our cognitive remediation programme's effects.

Autobiographical memory in chronic schizophrenia: A follow-up study

Chronic schizophrenia is a very disabling disease and patient's social integration remains difficult. One important aspect is autobiographical memory (AM) as it is impaired in schizophrenia and highly correlated to patient's outcome, since its closely linked to self and identity. Reduced specificity and lack of details are characteristics of patients' AM, but its longitudinal course in schizophrenia remains unclear. We examined 21 patients who underwent our protocol twice with an interval of 7 years. AM was assessed using a semi-structured interview, covering four periods of life and addressing semantic knowledge and autobiographical episodes as well as their details. The results can be divided into three parts, separating semantic memories, specific autobiographical memories and details describing the latter. While a significant deterioration of semantic AM over time could be revealed, the specificity of the free recalled autobiographical episodes remained rather stable - albeit on a low level. In contrast, unique events were remembered with significantly less details at follow-up than at the first examination. While floor-effects given a relatively small number of unique events have to be considered, semantic AM and episodic details seem to be a valuable target for AM remediation given their further deterioration over time.

Spurious Autobiographical Memory of Psychosis: A Mechanistic Hypothesis for the Resolution, Persistence, and Recurrence of Positive Symptoms in Psychotic Disorders

Psychotic disorders are complex disorders with multiple etiologies. While increased dopamine synthesis capacity has been proposed to underlie psychotic episodes, dopamine-independent processes are also involved (less responsive to dopamine receptor-blocking medications). The underlying mechanism(s) of the reduction in antipsychotic responsiveness over time, especially after repeated relapses, remain unclear. Despite the consistent evidence of dopamine overactivity and hippocampal volume loss in schizophrenia, few accounts have been provided based on the interactive effect of dopamine on hippocampal synapse plasticity mediating autobiographical memory processes. The present hypothesis builds upon previous works showing the potential effects of dopamine overactivity on hippocampal-mediated neuroplasticity underlying autobiographical memory, alongside known patterns of autobiographical memory dysfunction in psychosis. We propose that spurious autobiographical memory of psychosis (SAMP) produced during active psychosis may be a key mechanism mediating relapses and treatment non-responsiveness. In a hyperdopaminergic state, SAMP is expected to be generated at an increased rate during active psychosis. Similar to other memories, it will undergo assimilation, accommodation, and extinction processes. However, if SAMP fails to integrate with existing memory, a discontinuity in autobiographical memory may result. Inadequate exposure to normalizing experiences and hyposalience due to overmedication or negative symptoms may also impede the resolution of SAMP. Residual SAMP is hypothesized to increase the propensity for relapse and treatment non-responsiveness. Based on recent findings on the role of dopamine in facilitating hippocampal synapse plasticity and autobiographical memory formation, the SAMP hypothesis is consistent with clinical observations of DUP effects, including the repetition of contents in psychotic relapses as well as the emergence of treatment non-responsiveness after repeated relapses. Clinical implications of the hypothesis highlight the importance of minimizing active psychosis, integrating psychosis memory, avoiding over-medication, and fostering normalizing experiences.

Rumination as a Transdiagnostic Phenomenon in the 21st Century: The Flow Model of Rumination

Rumination and its related mental phenomena share associated impairments in cognition, such as executive functions and attentional processes across different clinical conditions (e.g., in psychotic disorders). In recent decades, however, the notion of rumination has been increasingly narrowed to the "self-focused" type in depressive disorders. A closer review of the literature shows that rumination may be construed as a broader process characterized by repetitive thoughts about certain mental contents that interfere with one's daily activities, not only limited to those related to "self". A further examination of the construct of rumination beyond the narrowly focused depressive rumination would help expand intervention opportunities for mental disorders in today's context. We first review the development of the clinical construct of rumination with regard to its historical roots and its roles in psychopathology. This builds the foundation for the introduction of the "Flow Model of Rumination (FMR)", which conceptualizes rumination as a disruption of a smooth flow of mental contents in conscious experience that depends on the coordinated interactions between intention, memory, affect, and external events. The conceptual review concludes with a discussion of the impact of rapid technological advances (such as smartphones) on rumination. Particularly in contemporary societies today, a broader consideration of rumination not only from a cognition viewpoint, but also incorporating a human-device interaction perspective, is necessitated. The implications of the FMR in contemporary mental health practice are discussed.

Autobiographical memory impairment in chronic schizophrenia: Significance and clinical correlates

Previous studies of autobiographical memory (AM) in schizophrenia yielded a reduction of specificity, richness of details and conscious recollection, which indicate both, quantitative and qualitative AM changes. However, their associations with psychopathological symptoms and neuropsychological deficits were not resolved. Therefore, we sought to investigate AM with respect to psychopathology and neuropsychology in patients with chronic schizophrenia to rule out the influence of different courses of the disease. AM of four lifetime periods was examined in 75 patients and 50 healthy controls by using a semi-structured interview. The recalled episodes were rated for memory specificity. Subsequently, one single event of each period of life was rated for details and experiential aspects of reliving (originality, vividness/visual imagery, emotional re-experiencing and emotional valence). When contrasted with healthy controls, patients recalled a significantly reduced number of episodes and personal semantic facts; moreover, memory specificity of AM was significantly lower in patients than controls. While the richness of details calculated for single events showed only minor, non-significant group differences, vividness and emotional re-experiencing were significantly less pronounced in the patient group. Along with this, AM performance correlated significantly with negative symptoms including apathy as well as verbal memory and executive functions. Our results underline the significance of overgenerality as a key feature of AM in schizophrenia as well as a dissociation between intact number of details of single events and reduced vividness and emotional re-experiencing. The extent of negative symptoms including apathy and impairments of verbal memory/executive functions may explain AM deficits in chronic schizophrenia.

“I remember the attack”: a pilot study investigating flashbulb memory in individuals with schizophrenia

Flashbulb memories are autobiographical memories for important and emotional events, which have the particularity of being at the intersection of personal and public events. Autobiographical memory impairments are highly prevalent in schizophrenia, a psychiatric condition intrinsically linked to self-disorders. Thus, we aimed to evaluate flashbulb and event memory functioning in individuals with schizophrenia. Twenty-four individuals diagnosed with schizophrenia and 25 control participants were tested on a flashbulb memory questionnaire about the July 14th, 2016, Nice (France) terrorist attack, including questions on flashbulb and event memory, certainty, vividness, rehearsal, emotion, novelty, consequentiality, implication, and importance. Participants also underwent cognitive assessments. Analysis showed lower scores for both flashbulb and event memories in patients compared to control participants. Subjective ratings of the phenomenological characteristics of flashbulb memory were similar between the two groups overall. However, individuals with schizophrenia reported having higher levels of emotion when they first learned about the attack compared to the control group. Our results replicate findings of impaired autobiographical memory functioning in schizophrenia and extend these findings to public events. Our findings also indicate that flashbulb memories may lead to substantial contextual recall in schizophrenia patients and that collective memories, such as a terrorist attack, can have a profound emotional impact on patients.

Autobiographical memory and the self on the psychosis continuum: investigating their relationship with positive- and negative-like symptoms

Autobiographical memory is severely impaired in schizophrenia, but previous work has largely treated both as unitary concepts. Here, we examined how various dimensions of autobiographical memory relate to different aspects of psychosis. Participants were recruited from the general population (Study 1, N = 264) and a university subject pool (Study 2, N = 305). We examined different measures of autobiographical memory and self (i.e., involuntary memory, autobiographical recollection, self-knowledge and self-awareness), at the trait level in Study 1 and both trait and state levels in Study 2, as a function of positive-and negative-like symptoms of psychosis. Across both studies, positive and negative dimensions of psychosis were found to be related to an increase in involuntary memories (i.e., the spontaneous recall of personal memories), and to lower self-concept clarity and insight. Positive and negative dimensions of psychosis correlated differently with autobiographical recollection characteristics, measured at both trait (Studies 1 and 2) and state levels (Study 2). Positive-like symptoms (in particular hallucination-proneness) showed a stronger and more consistent pattern of correlations than negative-like symptoms. These findings call for a dimensional approach to the relationship between autobiographical memory and psychosis symptoms in clinical and non-clinical individuals, to better understand the breakdown of autobiographical memory in the psychopathology of psychosis.

Functional disconnection between subsystems of the default mode network in schizophrenia

BACKGROUND

A dysfunctional default mode network (DMN) has been reported in patients with schizophrenia. However, the stability of the deficits has not been determined across different stages of the disorder.

METHODS

We examined the functional connectivity of the DMN subsystems of 125 patients with first-episode schizophrenia (FES) or recurrent schizophrenia (RES), compared to that of 82 healthy controls. We tested the robustness of the findings in an independent cohort of 158 patients and 39 healthy controls. We performed resting-state functional connectivity analysis, and examined the strength of the connections within and between the three subsystems of the DMN (core, dorsal medial prefrontal cortex [dMPFC], and medial temporal lobe [MTL]). We also analyzed the connectivity correlations to symptoms and illness duration.

RESULTS

We found reduced connectivity strength between the core and MTL subsystems in schizophrenia patients compared to controls, with no differences between the FES and RES patient groups; these findings were validated in the second sample. Schizophrenia patients also showed a significant reduction in connectivity within the MTL and between the dMPFC-MTL subsystems, similarly between FES and RES groups. The connectivity strength within the core subsystem was negatively correlated with clinical symptoms in schizophrenia. There was no significant correlation between the DMN subsystem connectivity and illness duration.

CONCLUSIONS

DMN subsystem connectivity deficits are present in schizophrenia, and the homochronicity of their appearance indicates the trait-like nature of these alterations. The DMN deficit may be useful for early diagnosis, and MTL dysfunction may be a crucial mechanism underlying schizophrenia.

Autobiographical memory in schizophrenia: The role of metacognition

BACKGROUND

Autobiographical memory is an important component of declarative memory, which refers to the ability to recall personal events that happened in the past. This requires that the person senses or experiences himself/herself in the past (i.e., conscious recollection). For people with schizophrenia, conscious recollection can be particularly difficult, resulting in difficulty accessing detailed, specific autobiographical information. Our hypothesis is that the ability to monitor and think about one's cognitive processes (metacognition) is a requisite for conscious recollection, and that it mediates the association between having schizophrenia and recalling fewer specific, personal memories.

METHODS

Participants were 30 adults with schizophrenia and 30 matched healthy controls. The main assessment instruments were the Metacognition Assessment Scale-Abbreviated (MAS-A) and the Autobiographical Memory Test (AMT). Severity of symptoms was assessed using the Positive and Negative Syndrome Scale (PANSS) for schizophrenia. Cognitive performance was measured with the Screen for Cognitive Impairment in Psychiatry (SCIP). Mediation analysis was conducted following Baron and Kenny's procedure.

RESULTS

People with schizophrenia had more semantic associations and fewer specific memories than controls in the AMT. Metacognition (MAS-A total score) partially mediated the association between having schizophrenia and recalling fewer specific past events, even after controlling for cognitive impairment as a potential confounding source.

CONCLUSIONS

Metacognitive ability, which can be improved with available programs, intervenes in the process of accessing autobiographical memories in people with schizophrenia. Practical implications of this finding are discussed.

Narrative identity in the psychosis spectrum: A systematic review and developmental model

Individuals with schizophrenia-spectrum disorders face profound challenges as they attempt to maintain identity through the course of illness. Narrative identity-the study of internalized, evolving life stories-provides a rich theoretical and empirical perspective on these challenges. Based on evidence from a systematic review of narrative identity in the psychosis spectrum (30 studies, combined N = 3859), we argue that the narrative identities of individuals with schizophrenia-spectrum disorders are distinguished by three features: disjointed structure, a focus on suffering, and detached narration. Psychotic disorders typically begin to emerge during adolescence and emerging adulthood, which are formative developmental stages for narrative identity, so it is particularly informative to understand identity disturbances from a developmental perspective. We propose a developmental model in which a focus on suffering emerges in childhood; disjointed structure emerges in middle and late adolescence; and detached narration emerges before or around the time of a first psychotic episode. Further research with imminent risk and early course psychosis populations would be needed to test these predictions. The disrupted life stories of individuals on the psychosis spectrum provide multiple rich avenues for further research to understand narrative self-disturbances.

The stability of visual perspective and vividness during mental time travel

When remembering or imagining, people can experience an event from their own eyes, or as an outside observer, with differing levels of vividness. The perspective from, and vividness with, which a person remembers or imagines has been related to numerous individual difference characteristics. These findings require that phenomenology during mental time travel be trait-like-that people consistently experience similar perspectives and levels of vividness. This assumption remains untested. Across two studies (combined N = 295), we examined the stability of visual perspective and vividness across multiple trials and timepoints. Perspective and vividness showed weak within-session stability when reported across just a few trials but showed strong within-session stability when sufficient trials were collected. Importantly, both visual perspective and vividness demonstrated good-to-excellent across-session stability across different delay intervals (two days to six weeks). Overall, our results suggest that people dependably experience similar visual phenomenology across occurrences of mental time travel.

How to project oneself without positive and integrated memories? Exploration of self-defining memories and future projections in bipolar disorder

Bipolar disorder (BD) is a disabling disorder with functional impact on everyday life. Recent studies suggest that autobiographical memory impairment may contribute to the maintenance of psychopathology, leading to enduring altered self-construct. Moreover, past personal experiences also support the ability to project oneself into the future to pre-experience an event, this capacity can be modified by psychiatric disorders. Self-defining memories and future projections by accessing highly significant events that are vivid and focused on central goals or enduring concerns can both provide a better understanding of the impact of disorders on self-perception and on the ability to project oneself into the future. Therefore we proposed to explore self-defining memories and future projections in BD patients (n = 25) compared to control participants (n = 25). BD patients' self-defining events were associated with more tension, life-threatening events, and negative emotion. BD patients also reported less integrated past but not less integrated future self-defining events. And their future projections were more closely related to leisure, and associated with positive emotions, compared to controls. For both groups, the future projections were less specific, integrated, and tense than the memories. These results question the self-coherence of patients' identity and should be confirmed to propose appropriate interventions to project oneself adaptively into the future and contribute to a better outcome.

Unraveling the role of retrieval deficits in autobiographical memory impairment in schizophrenia: A comparison of involuntary and voluntary autobiographical memories

Patients with schizophrenia show severe autobiographical memory impairment, thought to reflect retrieval deficits caused by executive dysfunction. However, prior research has focused exclusively on strategic (voluntary) retrieval, and ignored involuntary retrieval resulting from automatic and associative processes, involving minimal cognitive control. We report two studies with patients diagnosed with schizophrenia (Ns = 40 and 50 respectively) comparing their impairment in involuntary versus voluntary autobiographical memory. We use two different methodologies, not previously used in schizophrenia research: a naturalistic study involving real-life data and an experimental setup. Both studies consistently showed that involuntary and voluntary autobiographical memories were similarly impaired in schizophrenia. The absence of interaction effects between group and retrieval suggests that schizophrenic patients did not benefit from memory tasks involving little retrieval effort. These findings suggest that autobiographical memory impairment in schizophrenia are not caused by problems with self-initiated voluntary retrieval, but instead likely reflect encoding or binding deficits.

Remembering the past to live better in the future: A feasibility randomised controlled trial of memory specificity training for motivation in psychosis

BACKGROUND AND OBJECTIVES

People with a diagnosis of psychosis often experience low motivation and reduced activity levels. Autobiographical memory deficits have been identified in people with psychosis and this may limit the role of memory retrieval in supporting motivation. This pilot study adapted a recently developed protocol, Memflex, which aims to enhance autobiographical memory and has shown promise in depression. Our brief intervention targets experiential negative symptoms of psychosis using supported autobiographical memory retrieval.

METHOD

A sample of 31 participants with psychosis were recruited from inpatient and community settings and randomised in a 2:1 ratio to either a basic recall control or an enhanced recall intervention group. Participants were asked to generate positive autobiographical memories linked to activities they wish to repeat in the future. The enhanced recall condition received additional prompts from the Memflex protocol, and the basic recall condition received no additional support.

RESULTS

The intervention delivered was acceptable (rated >80%) and feasible (94% adherence) to those who took part. Participants were able to generate positive autobiographical memories linked to their goals and experienced appropriate emotions linked to these. The controlled preliminary effect sizes (0.2-0.34) showed encouraging signals for self-efficacy, motivation and a reduction in negative mood.

LIMITATIONS

As this was a pilot study with a small sample size between-group tests of statistical significance were not conducted, and therefore findings should be interpreted with caution.

CONCLUSIONS

These findings suggest that guided autobiographical memory retrieval may be an effective way tool for targeting motivation in people with psychosis.

Cognitive Intervention Targeting Autobiographical Memory Impairment in Patients With Schizophrenia Using a Wearable Camera: A Proof-of-Concept Study

Autobiographical memory (AM) impairment in schizophrenia affects the richness of detail in personal memories and is one of the major predictors of patients' social functioning. Despite the empirical evidence attributing these difficulties to a defective encoding process, cognitive remediation interventions targeting AM in schizophrenia often focus on the remote past, making it difficult to address the consequences of poor encoding. Our study evaluated the efficacy of an innovative approach using a wearable camera (NarrativeClip®) in reinforcing the encoding of recent daily life events in patients with schizophrenia. Seventeen patients with schizophrenia and 15 control participants wore the camera during four consecutive days. Then, memories of events experienced during these days were reinforced using different types of retrospective, i.e. interventions designed to promote a re-encoding of the event. We evaluated two types of retrospective using the camera pictures: a simple visual retrospective and a visual retrospective associated with a specific event-cueing (VisR+EC). These two techniques were compared to a verbal retrospective and to the absence of retrospective. Our results showed that the VisR+EC allowed patients to retrieve as many details as the control group at a two-week interval. However, patients' memories remained impaired when a simple visual or a verbal retrospective was used. Our study provides encouraging results to foster the use of a wearable camera in individualized cognitive remediation programs for AM impairment in schizophrenia.

Seeing or hearing one's memories: Manipulating autobiographical memory imagery in schizophrenia

The prevalence of auditory hallucinations in schizophrenia, and theories suggesting a link between autobiographical memory and hallucination, raise the possibility of a dominant role of auditory imagery in autobiographical remembering in patients with schizophrenia, whereas visual imagery is dominant in autobiographical memory of healthy adults. The present study explored this possibility by comparing autobiographical memory characteristics, according to sensory modality, in patients with schizophrenia versus healthy controls. Twenty-eight patients and 28 matched controls were asked to retrieve autobiographical memories that were dominated by auditory, visual, gustatory-olfactory, or tactile imagery. ANOVA analysis showed that patients rated their memories lower on specificity, contextual information, feeling of reliving, overall vividness, coherence and autobiographical me-ness (i.e. whether an autobiographical memory is experienced as belonging to the self), ps < 0.03, compared with control participants. The effects of sensory modality imagery were largely similar for patients and controls, as no interaction effects were observed. The findings did not support a dominance of auditory imagery in patients' autobiographical memory. In the patient group, reduced autobiographical me-ness was predicted by lower ratings of contextual information related to the setting of the event. Future research should examine whether these effects extend to involuntary autobiographical memory in schizophrenia.

Functioning of autobiographical memory specificity and self-defining memories in people with cancer diagnosis

OBJECTIVES

Cognitive and emotional disturbances have been associated with the diagnosis and treatment of cancer. Autobiographical memory is one of the specific cognitive processes affected during this disease. The current study had two main aims: (1) to compare the functioning of autobiographical memory specificity and its related variables (executive functioning, depression and perceived stress) in a group of persons with cancer and a control group; and (2) to analyze whether the experience of cancer evolved into a self-defining memory in the sample of participants diagnosed with this disease.

METHOD

The study sample comprised 62 participants, 31 in the group with a cancer diagnosis and 31 in the control group. Autobiographical memory specificity, executive functions, depression, stress and self-defining memory were evaluated in the current study.

RESULTS

Depressive symptomatology and reduced executive functioning, but not perceived stress levels, are related and are predictors of autobiographical memory specificity. In addition, the identified characteristics of the self-defining memories were associated with the cancer experience as a threat to physical integrity and an awareness of the meaning of life.

CONCLUSION

This emerging research line is especially important in view of its possible impacts on patients' well-being, due to the importance of psychological processes in cancer disease.

A review of autobiographical memory studies on patients with schizophrenia spectrum disorders

BACKGROUND

Patients suffering from schizophrenia spectrum disorders demonstrate various cognitive deficiencies, the most pertinent one being impairment in autobiographical memory. This paper reviews quantitative research investigating deficits in the content, and characteristics, of autobiographical memories in individuals with schizophrenia. It also examines if the method used to activate autobiographical memories influenced the results and which theoretical accounts were proposed to explain the defective recall of autobiographical memories in patients with schizophrenia.

METHODS

PsycINFO, Web of Science, and PubMed databases were searched for articles published between January 1998 and December 2018. Fifty-seven studies met the inclusion criteria. All studies implemented the generative retrieval strategy by inducing memories through cue words or pictures, the life-stage method, or open-ended retrieval method. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement guidelines were followed for this review.

RESULTS

Most studies reported that patients with schizophrenia retrieve less specific autobiographical memories when compared to a healthy control group, while only three studies indicated that both groups performed similarly on memory specificity. Patients with schizophrenia also exhibited earlier reminiscence bumps than those for healthy controls. The relationship between comorbid depression and autobiographical memory specificity appeared to be independent because patients' memory specificity improved through intervention, but their level of depression remained unchanged. The U-shaped retrieval pattern for memory specificity was not consistent. Both the connection between the history of attempted suicide and autobiographical memory specificity, and the relationship between psychotic symptoms and autobiographical memory specificity, remain inconclusive. Patients' memory specificity and coherence improved through cognitive training.

CONCLUSIONS

The overgeneral recall of autobiographical memory by patients with schizophrenia could be attributed to working memory, the disturbing concept of self, and the cuing method implemented. The earlier reminiscence bump for patients with schizophrenia may be explained by the premature closure of the identity formation process due to the emergence of psychotic symptoms during early adulthood. Protocol developed for this review was registered in PROSPERO (registration no: CRD42017062643).

Self-defining Memories Predict Engagement in Structured Activity in First Episode Psychosis, Independent of Neurocognition and Metacognition

BACKGROUND

Self-defining memories (SDMs) are vivid personal memories, related to narrative identity. Individuals with schizophrenia report less specific, more negative, and extract less meaning from these memories compared to control groups. SDMs have been shown to be predicted by neurocognition, associated with metacognition, and linked to goal outcomes in healthy controls. As neurocognition and metacognition are known predictors of poor functioning in psychosis, SDMs may also be a predictor. No study has assessed the relationship to functioning or pattern of SDMs in first episode psychosis (FEP).

METHODS

This was a cross-sectional study involving 71 individuals with FEP and 57 healthy controls who completed an SDM questionnaire. FEP participants completed measures of neurocognition, metacognition (Metacognitive Assessment Interview), functional capacity (The University of California, San Diego [UCSD] Performance-Based Skills Assessment), and functional outcome (Time-Use Survey).

RESULTS

SDMs reported by individuals with FEP were less integrated compared to healthy controls. Within the FEP sample, holding less specific memories was associated with engagement in significantly fewer hours of structured activity per week and specificity of SDMs mediated the relationship between neurocognition and functional outcome, independent of metacognition.

CONCLUSION

This is the first study to assess SDMs in FEP and to explore the important role of SDMs on clinical outcomes, compared to healthy controls. This study suggests that elaborating on specific SDMs is a valid therapeutic target and may be considered a tool to improve daily functioning in FEP.

Retrieval of negative autobiographical memories is associated with hostile attributions in ambiguous situations amongst people with schizophrenia

Schizophrenia is characterised by difficulty understanding the thoughts and intentions of other people. Misunderstandings could lead people to attribute hostility to others' actions. Theories suggest that we use our autobiographical memories to inform our understanding of other people but no study has examined the relation between memory and hostile attributions in schizophrenia. People with (n = 42) and without (n = 34) schizophrenia diagnoses completed The Ambiguous Intentions and Hostility Questionnaire (AIHQ) to assess their tendency to attribute hostility to other people's actions and the Autobiographical Memory Test (AMT) to assess their ability to recall specific positive and negative autobiographical memories. In linear regressions the interaction between diagnostic group and the proportion of specific negative memories participants retrieved explained significant variance in each AIHQ index. Follow-up correlation analyses showed that participants with schizophrenia who retrieved more negative memories also attributed greater hostility to other people's actions (r = 0.47) and reported that they would respond with greater aggression (r = 0.59). These correlations were in the opposite direction for controls. People with schizophrenia may use their memories for negative past events to understand the actions and intentions of other people, leading to attributions of hostility for otherwise benign actions.

Brain-Derived Neurotrophic Factor: A Key Molecule for Memory in the Healthy and the Pathological Brain

Brain Derived Neurotrophic Factor (BDNF) is a key molecule involved in plastic changes related to learning and memory. The expression of BDNF is highly regulated, and can lead to great variability in BDNF levels in healthy subjects. Changes in BDNF expression are associated with both normal and pathological aging and also psychiatric disease, in particular in structures important for memory processes such as the hippocampus and parahippocampal areas. Some interventions like exercise or antidepressant administration enhance the expression of BDNF in normal and pathological conditions. In this review, we will describe studies from rodents and humans to bring together research on how BDNF expression is regulated, how this expression changes in the pathological brain and also exciting work on how interventions known to enhance this neurotrophin could have clinical relevance. We propose that, although BDNF may not be a valid biomarker for neurodegenerative/neuropsychiatric diseases because of its disregulation common to many pathological conditions, it could be thought of as a marker that specifically relates to the occurrence and/or progression of the mnemonic symptoms that are common to many pathological conditions.

Functional fractionation of default mode network in first episode schizophrenia

A disruption in the connectivity between brain regions may underlie the core pathology in schizophrenia. One of the most consistent observations in human functional imaging is a network of brain regions referred to as the default network (DMN) that contains core subsystem, the dorsomedial prefrontal cortex (dMPFC) subsystem and the medial temporal lobe (MTL) subsystem, with differential contributions. The goal of this study was to examine abnormalities of different DMN subsystems in first episode schizophrenia and associations between these abnormalities and individual psychopathology. We recruited 203 patients and 131 healthy controls. A seed-based resting-state functional connectivity (RSFC) analysis on the 2D surface was conducted. Individual DMN functional connectivity matrices were then obtained by calculating spatial correlations between pairs of RSFC maps, characterizing the functional fractionation of the DMN. Patients showed patterns similar to controls but markedly reduced strength of DMN fractionation, with the degree centrality of the MTL subsystem significantly reduced, including the posterior inferior parietal lobule (pIPL), parahippocampal cortex (PHC) and lateral temporal cortex (LTC). Patients also exhibited hypo-connectivity within the MTL subsystem and between the MTL and dMPFC subsystems. Clinical symptoms were negatively correlated with degree centrality of LTC, pIPL and PHC in patients. Hyper-fractionation of different DMN components implied that communication and coordination throughout the dissociated components of the DMN are functionally over-segregated in schizophrenia. The associations between the hyper-fractionation with clinical symptoms suggest a role of the high fractionation in the DMN in the abnormal neuropathology observed in schizophrenia.

Association Between Connectivity of Hippocampal Sub-Regions and Auditory Verbal Hallucinations in Schizophrenia

Background: Hippocampal dysconnectivity has been detected in schizophrenia patients with auditory verbal hallucinations (AVHs). Neuroanatomical evidence has indicated distinct sub-regions in the hippocampus, but which sub-regions within the hippocampus may emerge dysfunction in the brain network, and the relationship between connection strength and the severity of this debilitating disorder have yet to be revealed. Masked independent component analysis (mICA), i.e., ICA restricted to a defined region of interest, can provide insight into observing local functional connectivity in a particular brain region. We aim to map out the sub-regions in the hippocampus with dysconnectivity linked to AVHs in schizophrenia.

Methods: In this functional magnetic resonance imaging study of schizophrenia patients with (n = 57) and without (n = 83) AVHs, and 71 healthy controls, we first examined hippocampal connectivity using mICA, and then the correlation between connection metric and clinical severity was generated.

Results: As compared with patients without AVHs, mICA showed a group of hyper-connections for the left middle part, as well as another group of hypo-connections for the bilateral antero-lateral and right antero-medial parts in patients with AVHs. Connectivity was linked to the clinical symptoms scores in the sample of patients with AVHs.

Conclusion: These findings demonstrate that the left middle part is more densely connected, but the bilateral antero-lateral and right antero-medial parts are more sparsely connected in schizophrenia patients with AVHs. The findings in the present study show proof of precious location in the hippocampus mediating the neural mechanism behind AVHs in schizophrenia.

Understanding the reminiscence bump: A systematic review

One of the most consistently observed phenomena in autobiographical memory research is the reminiscence bump: a tendency for middle-aged and elderly people to access more personal memories from approximately 10-30 years of age. This systematic review (PROSPERO 2017:CRD42017076695) aimed to synthesize peer-reviewed literature pertaining to the reminiscence bump. The researchers conducted searches in nine databases for studies published between the date of inception of each database and the year 2017. Keywords used included: reminiscence, bump, peak, surge, blip, reminiscence effect, and reminiscence component. Sixty-eight quantitative studies, out of 523, met the inclusion criteria. The researchers implemented a thematic analytic technique for data extraction. Four main themes were generated: methods of memory activation/instruction for life scripts, types of memory/life scripts recalled, location of the reminiscence bump, and theoretical accounts for the bump. The two prevailing methods of memory activation implemented were the cuing method and important memories method. Three types of memories/life scripts were recalled: personal/autobiographical memory, memories for public events, and life script events. The findings illustrate differing temporal periods for the bump: approximately 10-30 years for memories for important events, approximately 5-30 years for memories that were induced by word cues, and 6-39 years for studies using life scripts. In explaining the bump, the narrative/identity account and cultural life script account received the most support.

When your face describes your memories: facial expressions during retrieval of autobiographical memories

Thanks to the current advances in the software analysis of facial expressions, there is a burgeoning interest in understanding emotional facial expressions observed during the retrieval of autobiographical memories. This review describes the research on facial expressions during autobiographical retrieval showing distinct emotional facial expressions according to the characteristics of retrieved memoires. More specifically, this research demonstrates that the retrieval of emotional memories can trigger corresponding emotional facial expressions (e.g. positive memories may trigger positive facial expressions). Also, this study demonstrates the variations of facial expressions according to specificity, self-relevance, or past versus future direction of memory construction. Besides linking research on facial expressions during autobiographical retrieval to cognitive and affective characteristics of autobiographical memory in general, this review positions this research within the broader context research on the physiologic characteristics of autobiographical retrieval. We also provide several perspectives for clinical studies to investigate facial expressions in populations with deficits in autobiographical memory (e.g. whether autobiographical overgenerality in neurologic and psychiatric populations may trigger few emotional facial expressions). In sum, this review paper demonstrates how the evaluation of facial expressions during autobiographical retrieval may help understand the functioning and dysfunctioning of autobiographical memory.

The effect of impaired verbal memory retrieval on autobiographical memory across different life periods in schizophrenia

OBJECTIVES

Autobiographical memory (AM) involves recollection of personal events and facts about one's life. Αim of the present study was to investigate AM in schizophrenia patients, and, in particular, patients' ability to recall autobiographical memories after controlling for verbal memory and verbal fluency deficits.

METHOD

Participants included 40 schizophrenia patients (23 male) and 40 healthy controls (23 male), matched for age, gender, educational level, and premorbid intellectual functioning. Participants' verbal memory (list learning and story recall) and verbal fluency were assessed. AM was evaluated by the Questionnaire of Autobiographical Memory, consisting of the Personal Semantic Memory scale and the Autobiographical Incidents scale. Furthermore, personal incidents' specificity was examined.

RESULTS

Schizophrenia patients showed deficits in verbal memory and verbal fluency, as well as in both semantic and episodic AM compared with healthy controls. Deficits were shown in episodic and semantic memories of events and facts dating to three different life periods (childhood, early adulthood and recent life). Regarding specificity of recalled events, patients reported fewer specific autobiographical incidents than controls. After controlling AM deficits for patients' verbal memory and verbal fluency impairment, it was shown that schizophrenia patients recalled fewer memories of autobiographical incidents dating only to recent life, compared with healthy controls.

CONCLUSIONS

Schizophrenia patients showed impaired AM after controlling for verbal memory and verbal fluency impairment only in regard with personal episodic memories from recent life. Current findings raise the important issue of cognitive remediation therapy in schizophrenia.

The neural correlates of self-referential memory encoding and retrieval in schizophrenia

BACKGROUND

Enhanced memory for self-oriented information is known as the self-referential memory (SRM) effect. fMRI studies of the SRM effect have focused almost exclusively on encoding, revealing selective engagement of the medial prefrontal cortex (mPFC) during "self" relative to other processing conditions. Other critical areas for self-processing include ventrolateral prefrontal cortex (vlPFC), temporo-parietal junction (TPJ) and posterior cingulate/precuneus (PCC/PC). Previous behavioral studies show that individuals with schizophrenia fail to benefit from this memory boost. However, the neural correlates of this deficit, at either encoding or retrieval, are unknown.

METHODS

Twenty individuals with schizophrenia and 16 healthy controls completed an event-related fMRI SRM paradigm. During encoding, trait adjectives were judged in terms of structural features ("case" condition), social desirability ("other" condition), or as self-referential ("self" condition). Participants then completed an unexpected recognition test (retrieval phase). We examined BOLD activation during both encoding and retrieval within mPFC, vlPFC, TPJ, and PCC/PC regions-of-interest (ROIs).

RESULTS

During encoding, fMRI data indicated both groups had greater activation during the "self" relative to the "other" condition across ROIs. Controls showed this primarily in mPFC whereas patients showed this in PCC/PC. During retrieval, fMRI data indicated controls showed differentiation across ROIs between "self" and "other" conditions, but patients did not.

CONCLUSIONS

Results suggest regional differences in the neural processing of self-referential information in individuals with schizophrenia, perhaps because representation of the self is not as well established in patients relative to controls. The current study presents novel findings that add to the literature implicating impaired self-oriented processing in schizophrenia.

Personality traits are associated with the valence of future imagined events in individuals with schizophrenia

The relationships between the valence (positive or negative) of future imagined events and personality dimensions were examined in patients with schizophrenia. Correlational analyses showed that Extraversion was positively associated with the simulation of more positive future events whereas a statistical trend between Neuroticism and negative emotional valence was found. As in nonclinical individuals, personality is related to characteristics of mental time travel in schizophrenia patients.

Pathways from Trauma to Psychotic Experiences: A Theoretically Informed Model of Posttraumatic Stress in Psychosis

In recent years, empirical data and theoretical accounts relating to the relationship between childhood victimization and psychotic experiences have accumulated. Much of this work has focused on co-occurring Posttraumatic Stress Disorder or putative causal mechanisms in isolation from each other. The complexity of posttraumatic stress reactions experienced in psychosis remains poorly understood. This paper therefore attempts to synthesize the current evidence base into a theoretically informed, multifactorial model of posttraumatic stress in psychosis. Three trauma-related vulnerability factors are proposed to give rise to intrusions and to affect how people appraise and cope with them. First, understandable attempts to survive trauma become habitual ways of regulating emotion, manifesting in cognitive-affective, behavioral and interpersonal responses. Second, event memories, consisting of perceptual and episodic representations, are impacted by emotion experienced during trauma. Third, personal semantic memory, specifically appraisals of the self and others, are shaped by event memories. It is proposed these vulnerability factors have the potential to lead to two types of intrusions. The first type is anomalous experiences arising from emotion regulation and/or the generation of novel images derived from trauma memory. The second type is trauma memory intrusions reflecting, to varying degrees, the retrieval of perceptual, episodic and personal semantic representations. It is speculated trauma memory intrusions may be experienced on a continuum from contextualized to fragmented, depending on memory encoding and retrieval. Personal semantic memory will then impact on how intrusions are appraised, with habitual emotion regulation strategies influencing people's coping responses to these. Three vignettes are outlined to illustrate how the model accounts for different pathways between victimization and psychosis, and implications for therapy are considered. The model is the first to propose how emotion regulation and autobiographical memory may lead to a range of intrusive experiences in psychosis, and therefore attempts to explain the different phenomenological associations observed between trauma and intrusions. However, it includes a number of novel hypotheses that require empirical testing, which may lead to further refinement. It is anticipated the model will assist research and practice, in the hope of supporting people to manage the impact of victimization on their lives.