Autobiographical Memory Disturbances in Schizophrenia and the Psychosis Continuum: Integrating New Insights

Involuntary autobiographical memories are mental representations of personally experienced past events that come to mind spontaneously, with no preceding attempt to recall them. They have been showed to be more frequent and more emotional in the psychosis continuum. Although schizophrenia is strongly associated with thought disorders, including cognitive intrusions of thought, images, semantic knowledge, research on patients' involuntary autobiographical memories is limited. We undertook two studies to compare involuntary and voluntary remembering in schizophrenia and the conditions in which involuntary memories occurs in those patients, both in daily life (n = 40), using a diary method, and in an experimental context (n = 50). Overall, results showed that the conditions of elicitation of involuntary memories differ in patients, as patients were more sensitive to memory triggers, especially internal triggers, in comparison to controls. Relatedly, patients' involuntary memories—mostly related to mundane events with low emotional load—were experienced more frequently. Although patients' involuntary and voluntary memories were less clear, more poorly contextualized and associated with a lower belief in occurrence than those of controls, patients considered them as more central to the self, in comparison to controls. The results are discussed in relation to patients' self-reflective impairments.

This thesis examines age-related positivity effect in autobiographical memories. The goal was to gather further evidence to validate the Socioemotional Selectivity Theory (SST) and the Cognitive Control Theory (CCT) that explains why older adults would retrieve more positive and less negative memories when compared to younger adults. According to the SST, positivity effect in older adults occurs in view of their motivational shifts due to the limited time remaining in their life. Older adults work towards achieving their emotionally meaningful goals by recalling positive life experiences thus giving the positivity effect. The CCT, however, emphasises the importance of having sufficient cognitive resources, besides emotionally positive goals, to exercise cognitive control in order to achieve the positivity effect. Older adults with intact cognitive resources are more likely to direct their cognition towards recalling more positive memories. Because earlier studies mostly included Western and North European participants and produced contradictory findings, this thesis examines the plausibility of these two theories with samples taken from a non-Western country such as Malaysia. Six studies were conducted. Studies 1, 3, 4, 5, and 6 examined the SST, while studies 2, 3, 4, and 5 tested the CCT. In all studies except Study 5, participants retrieved autobiographical memories in response to cue words. Four studies compared the content of autobiographical memories retrieved by younger and older adult participants (Studies 1, 4, 5, & 6). Study 2 only involved older adults with the aim to examine if their cognitive performances were correlated with memory elements that were judged positive or negative. Study 3 compared younger and older participants, but it did not investigate memory elements; it only examined the overall valence ratings of the memories. In validating the SST, contradictory findings were revealed. Study 1 provided evidence to support the SST as older adults retrieved more positive events and expressed more positive emotions in their memories compared to younger adults. Study 3, which examined autobiographical memories retrieved under divided and full attention conditions clearly failed to support the SST as under full attention condition there was no age difference in the average emotional ratings of the memories. Study 4 examined age-related positivity effect in voluntary and involuntary autobiographical memories, and did not find support for the SST as younger and older participants’ voluntary memories contained an almost equal number of positive and negative elements. Study 5 examined positivity effect in recent and remote autobiographical memories, which also did not lend support to the SST because older and younger adults were not different in terms of positive elements reported in both types of memories. Study 6, however, offered strong support for the SST in which younger and older adults’ memories were primed with either neutral or spiritual phrases. The memories retrieved by older adults, when primed with neutral phrases, contained more positive elements compared to the negative elements while for the younger adults, their memories contained similar positive and negative elements. The studies examining the validity of CCT (Studies 2, 3, 4 and 5) also provided some supportive evidence. Study 2, which involved only older adults, revealed a significant negative correlation between negative memory elements and short-term spatial memory, meaning that the poorer the cognitive control, the more negativity is in older adults’ autobiographical memories. However, this study did not show significant correlation between positive elements and executive function. In Study 3, the memories retrieved by older adults under divided attention condition were rated as less pleasant compared to the memories retrieved under full attention condition. The divided attention condition was synonymous with the impaired cognitive control. Study 4 also supported CCT in terms of negative elements; older adults retrieved more negative elements in their involuntary memories (allowed less cognitive control) compared to voluntary memories (allowed more cognitive control). Older adults’ voluntary memories, however, did not contain more positive elements than involuntary memories that were expected for the support of CCT. Study 5 lent support to the CCT because there was more positive elements in remote (permitted more cognitive control) than recent memories (permitted less cognitive control) retrieved by older adults. Finally, as the supports for SST and CCT were not undisputed, recommendations for further research were outlined.

Involuntary autobiographical memories are memories of personally experienced events that come to mind spontaneously, whereas voluntary (i.e., deliberately recalled) memories are based on strategic retrieval processes, reflecting a goal-directed search.Previous work using an on-line recording methodology (i.e., a mechanical counter) has shown that involuntary compared with voluntary memories are three times as frequent in daily life, but there is evidence to suggest that frequency estimates of involuntary memories are sensitive to the methods used to make the recordings.Here, we use different types of on-line recording devices across three studies.In Study 1, using a mechanical counter, we replicated previous work showing that involuntary memories are almost three times as frequent as their voluntary counterparts.In Studies 2 and 3, we used smartphones to assess on-line frequency and found that the shift in recording device led to a decrease in the frequency of involuntary but not of voluntary memories.Furthermore, the smartphone assessment showed that involuntary memories were more frequent in the middle of the day, whereas voluntary retrieval was evenly distributed across the day.Voluntary relative to involuntary memories were estimated to serve more problem solving and directive functions in Studies 1 and 2 and as being more functionally relevant to the ongoing situation in Study 3. In conclusion, regardless of recording device, involuntary memories are at least as frequent as their voluntary counterparts, but are perceived to be less functionally relevant to the immediate retrieval context.

Ways of sampling voluntary and involuntary autobiographical memories in daily life.

Previous studies have produced inconsistent results concerning the two components of autobiographical memory--personal semantic memory and episodic memory. Results in subjects with mild cognitive impairment (MCI) and dementia of Alzheimer's type (DAT) have varied concerning the existence of a temporal gradient in retrograde amnesia. These results have important theoretical implications regarding multiple trace theory versus standard consolidation models of long-term memory (LTM). We investigated whether this variability arises from differences in the methods used in assessing autobiographical memory. We examined patterns of memory impairment in 20 healthy elderly controls, 20 MCI subjects, and 10 DAT subjects using the Autobiographical Memory Interview (AMI) of Kopelman and the Autobiographical Interview (AI) of Levine. Both the AMI and AI were modified to allow for the test scores to be derived from a single interview without fatiguing the subjects. On the AMI, DAT subjects were significantly impaired on both components of autobiographical memory--episodic memory and personal semantics--with episodic memory showing a significant though gentle temporal gradient sparing childhood memories. Using the AI test, subjects with DAT showed impaired recall of episodic details (but not personal semantics), again with a gentle temporal gradient. Differences between the two interview methods (fewer epochs in the AMI; fewer memories per epoch in the AI) were found to have a significant impact on the pattern of findings; fewer epochs in the AMI brought out the temporal gradient, and fewer memories per epoch (in the AI) diminished it. These data show the importance of technical details of the different tests in favouring one versus another LTM theory. The data are not purely compatible with either theory.

The frequency and characteristics of involuntary autobiographical memories were compared in 25 stable dysphoric and 28 non-dysphoric participants, using a new laboratory-based task (Schlagman & Kvavilashvili, 2008). Participants detected infrequent target stimuli (vertical lines) in a simple vigilance task and recorded any involuntary autobiographical memories that came to mind, mostly in response to irrelevant words presented on the screen. Dysphoric participants reported involuntary memories as frequently and as quickly as non-dysphoric participants and their memories were not repetitive intrusive memories of negative or traumatic events. Additional content analysis showed that dysphoric participants did not recall more memories of objectively negative events (e.g., accidents, illnesses, deaths) than non-dysphoric participants. However, significant group differences emerged in terms of a mood congruency effect whereby dysphoric participants rated their memories as more negative than non-dysphoric participants. Moreover, the proportion of negatively rated involuntary memories was related to lower mood ratings at the end of the session in the dysphoric but not in the non-dysphoric group. Finally, groups did not differ on several memory characteristics such as vividness, specificity (high in both groups) and rates of rehearsal (low in both groups). Theoretical and practical implications of these findings for research on depression and autobiographical memory are discussed.

Alzheimer's disease (AD) is characterized by severe memory alterations, affecting especially memories of personal past events. Until now, autobiographical memory impairments have been characterized using formal memory assessments, requiring patients to strategically and deliberately recall past events. However, contrary to this highly cognitively demanding mode of memory recall, autobiographical memories frequently come to mind unexpectedly based on automatic associative processes. The involuntary recall of personal memories is effortless and possibly represents a preserved way for AD patients to remember past events. This study aimed to investigate involuntary autobiographical memory in AD patients and compare the characteristics of these memories with those of healthy controls. Involuntary autobiographical memory was measured in 24 AD patients and 24 matched control participants using self-report measures. Participants were asked to report the frequency with which involuntary autobiographical memories were experienced in their daily life and to describe and self-assess one example of an involuntary memory. We showed that AD patients and control participants did not differ in terms of the frequency or subjective characteristics of their involuntary autobiographical memories in daily life, except for feelings of intrusiveness. Compared to control participants, AD patients reported their involuntary autobiographical memories as being more intrusive. In addition, more negative and vague involuntary autobiographical memories were associated with greater depressive symptoms. These findings open up a new avenue for research to better understand the extent to which involuntary autobiographical memory might be preserved in AD patients and why these memories may in turn become intrusive to patients.

In two studies, we compared the characteristics and retrieval times of involuntary and voluntary autobiographical memory under controlled laboratory conditions. A new laboratory task of involuntary autobiographical memories involved detecting vertical lines in a stream of stimuli with horizontal lines (an undemanding vigilance task) and recording any involuntary memories during the session. The majority of these memories were reported as being triggered by irrelevant cue phrases presented on the screen. Voluntary autobiographical memories were sampled via a standard word-cue method in Session 2. The results showed that involuntary memories were more specific and were retrieved significantly faster than voluntary memories. They were also more likely to be triggered by negative cues, whereas cue valence did not have any effect on the number of voluntary memories. Furthermore, laboratory involuntary memories did not differ from naturalistic involuntary memories recorded in a diary by the same participants (Study 2). Taken together, these results have important implications for current theories of autobiographical memory, and they open up interesting avenues for future research.

We utilised the recently developed continuous word association task (CWAT) to investigate whether attributes of involuntary autobiographical memory, including gender and cue valence effects, were similar to those found for voluntary autobiographical memory, as well as investigating the role of individual differences in memory production. A total of 80 undergraduate volunteers reported involuntary memories that came to mind during the word association task and completed measures of trait dissociation and psychosis-proneness. Involuntary memories showed similar cue valence effects to those typically found with voluntary memories but the usual gender effect was only apparent once participants learned the task involved autobiographical memory. The total number of involuntary autobiographical memories produced in response to negative cue words was related to greater trait dissociation and psychosis-proneness. The implications for differences between voluntary and involuntary autobiographical memory are discussed.

Involuntary autobiographical memories as a transdiagnostic factor in mental disorders.

Research on involuntary autobiographical memories has shown that such memories are also experienced as byproducts of voluntarily produced autobiographical memories [Mace, 2006. Episodic remembering creates access to involuntary conscious memory: Demonstrating involuntary recall on a voluntary recall task. Memory, 14(8), 917–924]. This study examined perceptions of these memories with respect to their evoking voluntary memories. Participants were engaged in an autobiographical memory recall task, and asked to report on the experience of involuntary memories. They were asked to report if involuntary memories and evoking voluntary memories were related, from the same lifetime period, if the involuntary memories had utility and relevance for evoking memories, and if the involuntary memories were experienced as intrusive. The results showed that involuntary memories were related to evoking voluntary memories, frequently from the same lifetime period, and generally not experienced as intrusive. While mostly perceived as relevant to evoking memories, less than one-half of the involuntary memories were perceived as useful. The results raise questions about the functional nature of this type of involuntary remembering.

I evaluate the conception of direct retrieval as originally formulated in the Self-Memory System model (Conway & Pleydell-Pearce [2000]. The construction of autobiographical memories in the self-memory system. Psychological Review, 107(2), 261–288. https://doi.org/10.1037/0033-295X.107.2.261). In the hierarchical memory organisation proposed in the Self-Memory System model, direct retrieval is described as a bottom-up associative process. While its theoretical role within this model is clear, systematic empirical examination of direct retrieval, viewed as a natural and observable phenomenon, has been hampered by inconsistent operationalisations. Here, I suggest that direct retrieval should be treated as a theoretical concept, aiming at explaining the phenomenon of involuntary (spontaneously arising) autobiographical memories. I evaluate predictions derived from the concept of direct retrieval against findings on involuntary autobiographical memories obtained over the past 25 years. Most of these predictions are consistent with the evidence, notably, the enhanced episodic specificity and constructive nature of involuntary autobiographical memories. However, the theory also has critical limitations. It did not predict the frequent occurrence of involuntary recollections in daily life, exceeding the prevalence of voluntary memories. Additionally, it overlooked the early emergence of spontaneously arising event memories in ontogenesis and their presence in other species, such as great apes. Future advancements of the Self-Memory System model should integrate evolutionary perspectives to address these limitations.

Involuntary autobiographical memories are memories of personal events that come to mind spontaneously-that is, with no conscious initiation of the retrieval process. Such spontaneously arising memories were long ignored in cognitive psychology, which generally has focused on controlled and strategic forms of remembering, studied in laboratory settings. Recent evidence shows that involuntary memories of past events are highly frequent in daily life, and that they represent a context-sensitive, and associative way of recollecting past events that involves little executive control. They operate by constraints that favour recent events and events with a distinct feature overlap to the current situation, which optimizes the probability of functional relevance to the ongoing situation. In addition to adults, they are documented in young children and great apes and may be an ontogenetic and evolutionary forerunner of strategic retrieval of past events. Findings suggest that intrusive involuntary memories observed clinically after traumatic events should be viewed as a dysfunctional subclass of otherwise functional involuntary autobiographical memories. Because of their highly constrained, situation-dependent and automatic nature, involuntary autobiographical memories form a distinct category of spontaneous thought that cannot be equated with mind wandering. This article is part of the theme issue 'Offline perception: voluntary and spontaneous perceptual experiences without matching external stimulation'.

Involuntary autobiographical memories come to mind effortlessly and unintended, but the mechanisms of their retrieval are not fully understood. We hypothesize that involuntary retrieval depends on memories that are highly accessible (e.g., intense, unusual, recent, rehearsed), while the elaborate search that characterizes voluntary retrieval also produces memories that are mundane, repeated or distant - memories with low accessibility. Previous research provides some evidence for this 'threshold hypothesis'. However, in almost every prior study, participants have been instructed to report only memories while ignoring other thoughts. It is possible that such an instruction can modify the phenomenological characteristics of involuntary memories. This study aimed to investigate the effects of retrieval intentionality (i.e., wanting to retrieve a memory) and selective monitoring (i.e., instructions to report only memories) on the phenomenology of autobiographical memories. Participants were instructed to (1) intentionally retrieve autobiographical memories, (2) intentionally retrieve any type of thought (3) wait for an autobiographical memory to spontaneously appear, or (4) wait for any type of thought to spontaneously appear. They rated the mental content on a number of phenomenological characteristics both during retrieval and retrospectively following retrieval. The results support the prediction that highly accessible memories mostly enter awareness unintended and without selective monitoring, while memories with low accessibility rely on intention and selective monitoring. We discuss the implications of these effects.

Involuntary (spontaneously arising) autobiographical memories and involuntary future thoughts are common in daily life, but their frequency and emotional intensity vary among individuals. Theories of hallucination in schizophrenia have hypothesized a key role for involuntary memories; however, this idea has been little examined. We report two studies, designed to address the role of involuntary mental events in relation to hallucination proneness. Both studies showed that the self-reported frequency of involuntary memories and future projections was a robust predictor of hallucination proneness, even when controlling for measures of unwanted thoughts and rumination (Study 1) and measures of depression, dissociation, executive functions, imagery abilities, and personality (Study 2). In Study 1, the emotional intensity of involuntary memories and future projections also predicted hallucination proneness. The findings open a new avenue of research addressing the role of involuntary autobiographical memories and future projections in relation to hallucination and psychosis.