Gender, personality, and involuntary autobiographical memory

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.     

Retrieval effort or intention: Which is more important for participants’ classification of involuntary and voluntary memories?

Theories of autobiographical memory distinguish between involuntary and voluntary memories. While involuntary memories are retrieved with no conscious intention and are therefore unexpected, voluntary memories are both intended and expected. Recent research has shown that participants sometimes classify their memories as either involuntary or voluntary based on retrieval effort instead of intention. These findings question whether intention really is the defining difference between these two types of retrieval or whether retrieval effort is also an important determinant. In two experimental studies, we investigated the extent to which participants rely on retrieval effort while classifying their memories as involuntary or voluntary. We created experimental conditions that maximize the probability of one type of retrieval while minimizing the probability of another type. Participants reported autobiographical memories in each condition while the programme registered their retrieval time. They then classified their memories as either voluntary or involuntary and rated all memories on perceived retrieval effort. This gave us four categories of memories: experimentally defined voluntary and involuntary memories with an objective measure of effort (retrieval time) and subjectively classified involuntary and voluntary memories with a subjective measure of effort. This allowed us to investigate the relative contribution of intention and effort to involuntary and voluntary memories. We replicated and extended previous findings by showing that the majority of memories were classified as involuntary independently of whether they were retrieved in the experimentally defined voluntary or involuntary condition. This could indicate that subjective effort is more important than intention for the involuntary–voluntary distinction in contrast with existing theories. We discuss theoretical and methodological implications of this finding.     

Involuntary autobiographical memories in and outside the laboratory: How different are they from voluntary autobiographical memories?

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.     

The reappearance hypothesis revisited: Recurrent involuntary memories after traumatic events and in everyday life

Recurrent involuntary memories are autobiographical memories that come to mind with no preceding retrieval attempt and that are subjectively experienced as being repetitive. Clinically, they are classified as a symptom of posttraumatic stress disorder. The present work is the first to systematically examine recurrent involuntary memories outside clinical settings. Study 1 examines recurrent involuntary memories among survivors of the tsunami catastrophe in Southeast Asia in 2004. Study 2 examines recurrent involuntary memories in a large general population. Study 3 examines whether the contents of recurrent involuntary memories recorded in a diary study are duplicates of, or differ from, one another. We show that recurrent involuntary memories are not limited to clinical populations or to emotionally negative experiences; that they typically do not come to mind in a fixed and unchangeable form; and that they show the same pattern regarding accessibility as do autobiographical memories in general. We argue that recurrent involuntary memories after traumas and in everyday life can be explained in terms of general and well-established mechanisms of autobiographical memory.     

Ways of sampling voluntary and involuntary autobiographical memories in daily life

Cognitive psychologists have often equaled retrieval of personal events with voluntary recall from autobiographical memory, but more recent research shows that autobiographical memories often come to mind involuntarily—that is, with no retrieval effort. Voluntary memories have been studied in numerous laboratory experiments in response to word-prompts, whereas involuntary memories primarily have been examined in an everyday living context, using a structured diary procedure. However, it remains unclear how voluntary memories sampled in the laboratory map onto self-prompted voluntary memories in daily life. Here, we used a structured diary procedure to compare different types of voluntary autobiographical memories to their involuntary counterparts. The results replicated previous findings with regard to differences between word-prompted voluntary and involuntary memories, whereas there were fewer differences between self-prompted voluntary and involuntary memories. The findings raise the question as to what is the best way of sampling voluntary memories and the best comparison for involuntary memories.     

Involuntary autobiographical memories are highly dependent on abstract cuing: the Proustian view is incorrect

This study investigated whether involuntary autobiographical memories are more likely to be elicited by fundamental sensory/perceptual cues (the popular Proustian interpretation) or abstract type of cues (thought and language based cues). Participants recorded their involuntary memories and the cues that elicited them outside of the laboratory for a period of two weeks. The results showed that involuntary memories were more likely to be elicited by abstract types of cues than sensory/perceptual cues, thus indicating that the popular Proustian view is incorrect. The higher rate of abstract cuing suggests that involuntary memory retrieval shares some common features with voluntary memory retrieval. Copyright © 2004 John Wiley & Sons, Ltd.     

Episodic remembering creates access to involuntary conscious memory: Demonstrating involuntary recall on a voluntary recall task

The idea that involuntary memory retrieval might occur during voluntary memory retrieval can be traced back to Ebbinghaus (1885/1964). However, methodological challenges have stood in the way of testing this idea. Recent diary studies of naturally occurring involuntary memories have provided insights into how this idea could be tested (Berntsen, 1998; Mace, 2005b, 2006). These studies have shown that the contents of an involuntary memory sometimes trigger additional involuntary memories, a process called chaining. It was hypothesised that chaining should also occur on autobiographical memory tasks, and this was tested in the present study by asking participants in an autobiographical memory task to report the presence of involuntary memories while they were performing the task. The results showed that involuntary memories did occur when participants were recalling the past. The results also showed involuntary memories dissociating from voluntary memories on two independent measures, thereby enhancing the credibility of the results.     

Episodic remembering creates access to involuntary conscious memory: demonstrating involuntary recall on a voluntary recall task

The idea that involuntary memory retrieval might occur during voluntary memory retrieval can be traced back to Ebbinghaus (1885/1964). However, methodological challenges have stood in the way of testing this idea. Recent diary studies of naturally occurring involuntary memories have provided insights into how this idea could be tested (Berntsen, 1998; Mace, 2005b, 2006). These studies have shown that the contents of an involuntary memory sometimes trigger additional involuntary memories, a process called chaining. It was hypothesised that chaining should also occur on autobiographical memory tasks, and this was tested in the present study by asking participants in an autobiographical memory task to report the presence of involuntary memories while they were performing the task. The results showed that involuntary memories did occur when participants were recalling the past. The results also showed involuntary memories dissociating from voluntary memories on two independent measures, thereby enhancing the credibility of the results.     

How intention to retrieve a memory and expectation that a memory will come to mind influence the retrieval of autobiographical memories

While involuntary memories are retrieved with no intention and are usually unexpected (when one is not waiting for a memory to arise), voluntary memories are intended and expected (when one is searching and waiting for a memory to arise). The present study aimed to investigate the effects of retrieval intentionality (i.e. wanting to retrieve a memory) and monitoring processes (i.e. waiting for a memory to appear) during autobiographical memory retrieval. In addition, we introduced two novel laboratory conditions that have not been used in previous research on voluntary memories: in the first, participants were asked to report anything they could think of in response to each cue word; in the second, they could skip a word if nothing came to mind. These novel manipulations allowed us to differentiate between voluntary memories retrieved in response to experimenter-generated cues (when participants were forced to provide a memory or a thought for each cue) and self-selected cues (when participants were free to not answer a cue if they found it too difficult). We found that highly accessible memories were mostly experienced when retrieval was involuntary and unexpected, while memories with low accessibility were accessed through intentional retrieval and monitoring processes. Response times for memories recalled in the experimenter-generated cue conditions were longer compared to the self-selected cue conditions. This novel finding shows that experimenter-generated recall favours memories with low accessibility; it further supports the idea that, in a substantial number of trials, voluntary memories are directly rather than effortfully retrieved. The idea that the driving force behind differences between involuntary and voluntary memories is not the intention per se is further discussed.     

Current concerns in involuntary and voluntary autobiographical memories

Involuntary autobiographical memories are conscious memories of personal events that come to mind with no preceding attempts at retrieval. It is often assumed that such memories are closely related to current concerns – i.e., uncompleted personal goals. Here we examined involuntary versus voluntary (deliberately retrieved) autobiographical memories in relation to earlier registered current concerns measured by the Personal Concern Inventory (PCI; Cox & Klinger, 2000). We found no differences between involuntary and voluntary memories with regard to frequency or characteristics of current concern-related contents. However, memories related to current concerns were rated as more central to the person’s identity, life story and expectations for the future than non-concern-related memories, irrespective of mode of recall. Depression and PTSD symptoms correlated positively with the proportion of current concern-related involuntary and voluntary memories. The findings support the view that involuntary and voluntary remembering is subject to similar motivational constraints.     

How intention and monitoring your thoughts influence characteristics of autobiographical memories

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.     

The characteristics of involuntary and voluntary autobiographical memories in depressed and never depressed individuals

This study compares involuntary and voluntary autobiographical memories in depressed and never depressed individuals. Twenty depressed and twenty never depressed individuals completed a memory diary; recording their reactions to 10 involuntary and 10 voluntary memories over 14-30days. Psychiatric status (Structured Clinical Interview for DSM-IV, SCID-1), psychopathology, rumination and avoidance were assessed. For both groups, involuntary memories more frequently lead to strong reactions than voluntarily memories. For both modes of retrieval, depressed individuals reported more frequent negative reactions than never depressed individuals and rated memories as more central to identity with higher levels of rumination and avoidance. Depressed individuals retrieved both positive and negative memories during involuntary retrieval. These findings support the view that involuntary memory retrieval represents a basic mode of retrieval during healthy and disordered cognition, and that during depression, both involuntary and voluntary memories are central to identity and associated with rumination and avoidance.     

Does retrieval intentionality really matter? Similarities and differences between involuntary memories and directly and generatively retrieved voluntary memories

Theories of autobiographical memory distinguish between involuntary and voluntary retrieval as a consequence of conscious intention (i.e., wanting to remember). Another distinction can be made between direct and generative retrieval, which reflects the effort involved (i.e., trying to remember). However, it is unclear how intention and effort interacts. For example, involuntary memories and directly retrieved memories have been used interchangeably in the literature to refer to the same phenomenon of effortless, non‐strategic retrieval. More recent theoretical advances suggest that they are separate types of retrieval, one unintentional (involuntary), another intentional and effortless (direct voluntary retrieval), and a third intentional and effortful (generative voluntary retrieval). Whether this also entails differing phenomenological characteristics, such as vividness, rehearsal, or emotional valence, has not been previously investigated. In the current study, participants reported memories in an experimental paradigm designed to elicit voluntary and involuntary memories and rated them on a number of characteristics. If intention affects the retrieval process, then we should expect differences between the characteristics of involuntary and directly retrieved memories. The results imply that retrieval intention seems to differentiate how a memory appears in a person's mind. Furthermore, we argue that these differences in part could result from differences in encoding and consolidation.     

Visual object imagery and autobiographical memory: Object Imagers are better at remembering their personal past

In the present study we examined whether higher levels of object imagery, a stable characteristic that reflects the ability and preference in generating pictorial mental images of objects, facilitate involuntary and voluntary retrieval of autobiographical memories (ABMs). Individuals with high (High-OI) and low (Low-OI) levels of object imagery were asked to perform an involuntary and a voluntary ABM task in the laboratory. Results showed that High-OI participants generated more involuntary and voluntary ABMs than Low-OI, with faster retrieval times. High-OI also reported more detailed memories compared to Low-OI and retrieved memories as visual images. Theoretical implications of these findings for research on voluntary and involuntary ABMs are discussed.     

Priming autobiographical memories: How recalling the past may affect everyday forms of autobiographical remembering

This study investigated the idea that when one recalls past episodes, that the content of those memories will activate additional episodic memories with like content, and such memories will then have the potential of surfacing in subsequent acts of involuntary and voluntary recall. We tested the episodic content priming hypothesis in two experiments. In Experiment 1, priming group participants first recalled memories about specific activities or events and then they were subsequently engaged in a word-cue voluntary autobiographical memory task. The results showed that priming group participants produced more episodic memories involving the primed content on this task than control participants occupied in the same task. In Experiment 2, episodic content priming was further tested on a measure of involuntary autobiographical memory (i.e., the vigilance task). The results on this task also revealed support for the episodic content priming hypothesis, including after a delay of 24 h.     

The episodic nature of involuntary autobiographical memories

Involuntary autobiographical memories are conscious and unintended recollections of personal experiences. In Study 1, involuntary memories were compared with voluntary word-cued memories, both retrieved in naturalistic settings via a self-paced procedure. The involuntary memories more frequently referred to specific episodes, came with more physical reaction, had more impact on mood, and dealt with more unusual and less positive events. Study 2 demonstrated that these differences were not due to differences between verbal and nonverbal cues, by using Francis Galton's "memory walk" as a nonverbal method to cue voluntary memories. In both studies, systematic differences were found between specific and nonspecific memories. The findings show that the way autobiographical memories are sampled greatly affects the findings and that involuntary retrieval more often provides access to memories of specific episodes and associated emotional states.     

The effect of emotional stress on involuntary and voluntary conscious memories

Clinical theories of post-traumatic stress disorder often claim that intrusive (involuntary) memories favour emotionally stressful material and that these memories come with more sensory imagery and emotional reliving compared to voluntary memories. However, these assumptions have not been verified experimentally. Here we obtained recordings of emotional reactions to aversive pictures at the time of encoding, as well as records of involuntary and voluntary memories of these pictures in a subsequent diary study. A comparison of individual ratings, obtained during encoding, of pictures recalled involuntarily and voluntarily showed that emotional stress at encoding increased overall accessibility, independent of whether recall was voluntary or involuntary. However at the time of recall, voluntary memories scored higher on narrative content and on measures of imagery. The findings are compatible with research on emotion and memory in general, but challenge clinical claims of differential involuntary versus voluntary access to emotionally stressful events.     

Memory in posttraumatic stress disorder: properties of voluntary and involuntary, traumatic and nontraumatic autobiographical memories in people with and without posttraumatic stress disorder symptoms

One hundred fifteen undergraduates rated 15 word-cued memories and their 3 most negatively stressful, 3 most positive, and 7 most important events and completed tests of personality and depression. Eighty-nine also recorded involuntary memories online for 1 week. In the first 3-way comparisons needed to test existing theories, comparisons were made of memories of stressful events versus control events and involuntary versus voluntary memories in people high versus low in posttraumatic stress disorder (PTSD) symptom severity. For all participants, stressful memories had more emotional intensity, more frequent voluntary and involuntary retrieval, but not more fragmentation. For all memories, participants with greater PTSD symptom severity showed the same differences. Involuntary memories had more emotional intensity and less centrality to the life story than voluntary memories. Meeting the diagnostic criteria for traumatic events had no effect, but the emotional responses to events did. In 533 undergraduates, correlations among measures were replicated and the Negative Intensity factor of the Affect Intensity Measure correlated with PTSD symptom severity. No special trauma mechanisms were needed to account for the results, which are summarized by the autobiographical memory theory of PTSD.     

A content analysis of involuntary autobiographical memories: examining the positivity effect in old age

Although research on autobiographical memory is growing steadily, very little is known about involuntary autobiographical memories that are spontaneously recalled in everyday life. In addition, very few studies have examined the actual content of autobiographical memories and how the content might change as a function of age. The present study carried out a content analysis of involuntary autobiographical memories recorded by young (N = 11) and old (N = 10) volunteers over a period of 1 week. A total of 224 memories were classified into 17 categories according to the type of content recalled (e.g., births, holidays, school). The results support the socioemotional theory of ageing (Carstensen, Isaacowitz & Charles, 1999) by showing that although young and old adults recalled a similar number of memories with a typically positive content (e.g., holidays, special occasions), older adults recalled very few memories with a typically negative content (e.g., accidents, stressful events). Moreover, even when such negative memories were recalled, they were rated by older adults as neutral or even positive. This so-called positivity effect in old age could not be entirely explained by participants' ratings of mood at the time of recall. Theoretical and practical implications of these findings for ageing and autobiographical memory research are discussed.     

Relationship between frequency of involuntary autobiographical memories and cognitive failure

Involuntary autobiographical memories are memories of personal experiences that pop into mind without a conscious attempt at their retrieval. This study investigated individual differences in the number of involuntary autobiographical memories, and explored the relationship between the frequency of occurrence in involuntary autobiographical memory and cognitive failures in everyday memory, as indexed by metamemory questionnaires. A total of 24 undergraduate students reported involuntary autobiographical memories in controlled field interviews, and completed the Everyday Memory Questionnaire and the Cognitive Failures Questionnaire. The results showed that, despite controlled conditions, considerable individual differences were observed in the number of involuntary autobiographical memories reported while walking along a prescribed route on the campus, and that reported memories were predominantly serving self function. In addition, the number of involuntary autobiographical memories was positively related to cognitive failures in everyday memory: participants who acknowledged more problems in everyday memory had a higher frequency of involuntary memories. The implications of these results are discussed in terms of the complementary function of involuntary autobiographical memory in everyday life.