Spontaneous future cognitions: an integrative review

On second thoughts: Testing the underlying mechanisms of spontaneous future thought

The human capacity to imagine possible future events unintentionally, with minimal cognitive effort, is termed spontaneous future thought (SFT). This paper addresses an important theoretical question for cognitive science: What are the possible cognitive mechanisms underlying such SFT experiences? We contrasted three hypotheses present in the literature: the online construction hypothesis, the recasting hypothesis, and the memories of future thoughts hypothesis. Study 1 (N = 41) used novel subjective ratings which challenged the recasting mechanism: SFTs were mostly rated as dissimilar to autobiographical memories, suggesting they are not simply past experiences 'recast' as future events. Study 2 (N = 90) used a novel experimental paradigm, comparing effects of voluntary episodic future constructions and non-personal narratives upon subsequent spontaneous thought sampling. Results suggested that voluntary future constructions remain accessible to spontaneous retrieval, supporting the memories of future thoughts hypothesis. This finding, and other data presented across the two studies, still indicates a role for online construction processes in SFT, but further empirical work is needed to clarify how and when constructive processes are engaged in SFT. Taken together, these two studies represent initial efforts to elucidate the mechanisms underlying SFT, providing the first proof-of-principle that deliberately envisioned future events can reappear, without intention, in consciousness at some later time, and further supporting the dual process account of future thinking. These methods and findings provide a firm basis for subsequent experimental and longitudinal research on SFT.

Mental threat rehearsal increases fear generalization

BACKGROUND AND OBJECTIVES

Fear generalization to harmless stimuli characterizes anxiety-related disorders, but much remains unknown about its determinants. Based on studies showing that mental imagery of threat can increase conditioned fear responding, we tested whether it also facilitates fear generalization, and whether threat inflation moderates this effect.

METHODS

In a fear conditioning study, 120 participants first completed an acquisition phase, in which one of two pictures was followed by an aversive sound (human scream). Then, the sound was presented 11 times at an increasing (threat inflation) or constant volume (no threat inflation). Finally, a generalization stimulus was presented, and some participants were asked to imagine the last sound (threat rehearsal) and others were not (no threat rehearsal).

RESULTS

Bayesian informative hypotheses tests indicated that imagery-based threat rehearsal increased generalization of threat expectancy, and, combined with threat inflation, it also resulted in stronger generalized distress.

LIMITATIONS

due to the absence of a test phase, it is unclear whether our effects would transfer to other GSs and whether they would persist beyond the manipulation phase.

CONCLUSIONS

Mental imagery of threat may put individuals at risk for fear generalization. Future studies should examine whether modulating imagery may prevent clinical anxiety.

A dual process model of spontaneous conscious thought

In the present article, I review theory and evidence on the psychological mechanisms of mind wandering, paying special attention to its relation with executive control. I then suggest applying a dual-process framework (i.e., automatic vs. controlled processing) to mind wandering and goal-directed thought. I present theoretical arguments and empirical evidence in favor of the view that mind wandering is based on automatic processing, also considering its relation to the concept of working memory. After that, I outline three scenarios for an interplay between mind wandering and goal-directed thought during task performance (parallel automatic processing, off-task thought substituting on-task thought, and non-disruptive mind wandering during controlled processing) and address the ways in which the mind-wandering and focused-attention spells can terminate. Throughout the article, I formulate empirical predictions. In conclusion, I discuss how automatic and controlled processing may be balanced in human conscious cognition.

The frequency and cueing mechanisms of involuntary autobiographical memories while driving

Involuntary autobiographical memories (IAMs) have been typically studied with paper diaries, kept for a week or longer. However, such studies are unable to capture the true frequency of IAMs, nor the level of detail that would give new insights into the mechanisms of IAMs. To address this gap, a new audio-recording method was developed and tested on the first author who recorded 674 IAMs while driving a car on a 30-40-minute-long habitual route on 20 occasions. Results revealed very high frequency of IAMs (almost 34 per journey) that were reported more often in response to dynamic (one-off) than static cues. Moreover, a substantial number of memory chains and long-term priming of IAMs by previously encountered incidental stimuli were also recorded. Based on these results, a new theoretical model is proposed in which the occurrence of IAMs is determined by an interplay of factors at the time of the IAM, such as the type of ongoing activity and internal or external triggers, as well as different types of long-term priming. The results also have practical implications for studying mind-wandering and safety issues in driving and aircraft-flying, where periods of concentration are followed by monotony and less demanding tasks.

Sleeping poorly is robustly associated with a tendency to engage in spontaneous waking thought

We spend approximately-one third of our lives sleeping, and spontaneous thoughts dominate around 20-50% of our waking life, but little is known about the relation between the two. Studies examining this relationship measured only certain aspects of sleep and certain forms of spontaneous thought, which is problematic given the heterogeneity of both conceptions. The scarce literature suggests that disturbed sleep and the frequency of spontaneous waking thoughts are associated, however this could be caused by shared variance with negative affect. We report a comprehensive survey study with a large range of self-reported sleep and spontaneous thought measures (N = 236), showing that poorer sleep quality, more daytime-sleepiness, and more insomnia symptoms, consistently predicted higher tendencies to engage in disruptive spontaneous thoughts, independently of trait negative affect, age and gender. Contrarily, only daytime sleepiness predicted positive-constructive daydreaming. Findings underscore the role of sleep for spontaneous cognition tendencies.

Sleep well, mind wander less: A systematic review of the relationship between sleep outcomes and spontaneous cognition

Despite an upsurge of research on spontaneous cognition, little is known about its associations with sleep-related outcomes. This systematic review, following PRISMA guidelines, examined the relationship between sleep and spontaneous thoughts, across different definitions and measurements of sleep outcomes and spontaneous cognition, and a diversity of methodologies. Twenty-one articles with survey and/or experimental designs were identified. Self-reported disturbed sleep-comprising poor sleep quality, more insomnia symptoms, more daytime sleepiness and a tendency towards eveningness-and experimentally induced sleep deprivation were associated with a tendency to engage in disruptive mind wandering and daydreaming, but not positive-constructive daydreaming. Findings regarding circadian fluctuation in spontaneous thoughts were mixed and inconclusive. This systematic review bridges the gap between the sleep and spontaneous cognition research by contributing to the understanding of potential psychological and cognitive mechanisms of spontaneous cognition, as well as by elucidating the emotional and cognitive consequences of disturbed sleep.

Effects of inhibitory control capacity and cognitive load on involuntary past and future thoughts: A laboratory study

The present study focused on involuntary thoughts about personal past events (i.e., involuntary autobiographical memories; IAMs), and involuntary thoughts about future events and plans (i.e., involuntary future thoughts; IFTs). The frequency of these involuntary thoughts is influenced by cognitive demands of ongoing activities, but the exact underlying mechanism(s) has yet to be revealed. The present study tested two possible explanations: (1) the special inhibitory mechanism switches on when one is engaged in attentionally demanding activities; (2) different levels of cognitive load interfere with cue-noticing that act as triggers for IAMs and IFTs. We report a study with pre-selected groups of participants that differed in terms of their individual level of inhibitory control capacity (high vs. low), and completed both standard and attentionally demanding versions of a laboratory vigilance task with irrelevant cue-words to trigger IAMs and IFTs, and random thought-probes to measure their frequency. To examine the level of incidental cue-noticing, participants also completed an unexpected cue-recognition task. Despite large differences between groups in inhibitory control capacity, the number of IFTs and IAMs, reported in the attentionally demanding condition, was comparable. In addition, high cognitive load reduced the number of IAMs, but not IFTs. Finally, the recognition of incidental cues encountered in the vigilance task was reduced under high cognitive load condition, indicating that poor cue-noticing may be the main underlying mechanism of cognitive load effect rather than the lack of inhibitory resources needed to suppress involuntary retrieval. This and other possible mechanisms and avenues for future research are discussed.

Emotional mental imagery generation during spontaneous future thinking: relationship with optimism and negative mood

Optimism is known to buffer against negative mood. Thus, understanding the factors that contribute to individual variation in optimism may inform interventions for mood disorders. Preliminary evidence suggests that the generation of mental imagery-based representations of positive relative to negative future scenarios is related to optimism. This study investigated the hypothesis that an elevated tendency to generate positive relative to negative mental imagery during spontaneous future thinking would be associated with reduced negative mood via its relationship to higher optimism. Participants (N = 44) with varied levels of naturally occurring negative mood reported current levels of optimism and the real-time occurrence and characteristics of spontaneous thoughts during a sustained attention computer task. Consistent with hypotheses, higher optimism statistically mediated the relationship between a higher proportional frequency of positive relative to negative mental imagery during spontaneous future thinking and lower negative mood. Further, the relationship between emotional mental imagery and optimism was found for future, but not past, thinking, nor for verbal future or past thinking. Thus, a greater tendency to generate positive rather than negative imagery-based mental representations when spontaneously thinking about the future may influence how optimistic one feels, which in turn may influence one's experience of negative mood.

Personal characteristics of World War Two survivor offspring related to the presence of indirect intrusions

Background: A substantial proportion of clinical World War Two survivor offspring reports intrusions about war events they did not experience themselves. Objective: To help identify factors that contribute to the development of such indirect intrusions (i.e. intrusions about non-self-experienced traumatic events), we examined the personal characteristics of survivor offspring that were related to the presence of indirect intrusions. To explore the specificity of these relationships, we compared characteristics related to the presence of indirect and direct intrusions (i.e. intrusions about self-experienced traumatic events). Methods: Participants (N = 98) were post-war offspring of World War Two survivors in treatment in one of two clinics specialized in mental health services for war victims. We assessed the presence of indirect and direct intrusions as well as the following personal characteristics: gender, education level, trait dissociation, affect intensity, attentional control, mental imagery, fantasy proneness, and current psychopathology. Results: Reports of indirect intrusions were more frequent in individuals high in fantasy proneness, trait dissociation, and current psychopathology. Reports of direct intrusions were more frequent in women, individuals scoring high on trait dissociation, affect intensity, and current psychopathology. Fantasy proneness was a unique correlate of indirect intrusions. Conclusions: These findings are consistent with the idea that intrusions are the result of (re)constructive processes affected by several factors including personal characteristics.

HIGHLIGHTS

Offspring of World War Two survivors often experience indirect intrusions.We examined personal characteristics related to indirect and direct intrusions.Fantasy proneness was the best predictor of indirect intrusions.Gender was the best predictor of direct intrusions.

The role of inhibitory control and ADHD symptoms in the occurrence of involuntary thoughts about the past and future: An individual differences study

In everyday life, people often experience involuntary thoughts about their personal past and future events in response to incidental cues in the environment. Yet, despite the abundance of such cues, our consciousness is not constantly flooded by these involuntary autobiographical memories (IAMs) and involuntary future thoughts (IFTs). The main goal of the present study was to further investigate the possibility that cognitive inhibitory control keeps these involuntary cognitions at bay. To test this inhibition hypothesis, we conducted a large-scale study (n = 157) in which groups of participants with different levels of inhibitory control (low, medium, high) and individuals with ADHD spectrum symptoms were engaged in a laboratory vigilance task in which the frequency of IFTs and IAMs was assessed. Contrary to predictions, although participants across groups differed significantly in terms of their individual inhibitory control capacity, the number of IFTs and IAMs reported during the vigilance task was comparable. In addition, individuals with the ADHD spectrum symptoms did not report more spontaneous thoughts compared to other groups. Together, these findings lend little support for the idea that inhibition is a key mechanism that regulates the occurrence of IAMs and IFTs in everyday life. Other possible mechanisms and avenues for future research are discussed.

Acute impact of self-guided mental imagery on craving in cocaine use disorder: a mixed-methods analysis of a randomized controlled trial

Mental imagery manipulations are used to treat several psychological disorders, but their utility in treating cocaine use disorder (CUD) is unknown. Using prompted re-experiences and simulations with contrasting valence, we assessed the acute impact of a deliberate mental imagery task on cocaine craving.

DESIGN

A quantitative-qualitative 'mixed-methods' analysis of data collected for a randomized controlled trial that was stopped prematurely.

SETTING

UK National Health Service addictions treatment clinic and outpatient clinical research facility (laboratory).

PARTICIPANTS

Adults with CUD. The original target sample was 120. All participants enrolled at the point the original trial was stopped were included (38 enrolled, 31 completed study).

INTERVENTIONS

Personalized (3-minute) cue-exposure (handling cocaine paraphernalia and watching video of drug preparation), immediately followed by a single 5-minute, audio-recorded, self-guided and verbally described imagery task with random assignment to one of four conditions: two mental imagery memory re-experiences (positive image before initiation to cocaine use or a negative image of a 'worst time' adverse cocaine use episode) or two future simulations (positive theme of recovery from CUD or negative theme of worsened CUD).

MEASUREMENTS

Task transcripts were rated for imagery detail using five dimensions using a six-point scale of imagery detail (ID) (total score = 0-25) and thematically coded. The outcome measure was cocaine craving using the Craving Experiences Questionnaire-strengths version (CEQ-S11; score = 0-110) reported at baseline, arrival at the laboratory, and immediately after the cue-exposure and mental imagery tasks.

FINDINGS

A mixed-effects, longitudinal, restricted linear regression, with the past-positive imagery condition as referent, showed main effects of reduced craving after the imagery task (b = -29.2, 95% confidence interval (CI) = -45.3 to -13.1, P-value < 0.001) and increased craving for the future-negative task (b = 14.2, 95% CI = 0.1-28.4, P-value 0.049). There was a future-negative task by post-imagery craving interaction (b = 28.1, 95% CI = 0.1-56.1, P-value 0.049). A theory-driven, deductive/inductive qualitative analysis of the transcripts revealed six major themes: sensory characteristics, CUD vicious cycle, self-care, emotions and appraisals, social role and CUD recovery. Positively themed simulations included interpersonal connections and rewarding activity; negative images included personal adversity, with appraisals of self-criticism and hopelessness. Transcripts with more imagery detail were not associated with significantly greater reductions in craving in the positive or negative imagery task (r = -0.32, 95% CI = -0.69 to 0.13 and r = 0.06, 95% CI = -0.58 to 0.53, respectively).

CONCLUSION

In people with cocaine use disorder, after cue-exposure, a self-guided imagery task with positive themes reduced craving, whereas mental imagery simulating worsened cocaine use disorder did not appear to.

Episodic-semantic interactions in spontaneous thought

The distinction between a semantic memory system, encompassing conceptual knowledge, and an episodic memory system, characterized by specific episodes, is one of the most important theoretical proposals in cognitive science. However, the distinction between systems has rarely been discussed in relation to spontaneous thought that comes to mind with reduced cognitive effort and intentionality. In this review, we propose that the growing research on spontaneous thought can contribute to current discussions on the interaction between the episodic and semantic systems. Firstly, we review research that shows that, as in deliberate retrieval, spontaneous thoughts are influenced by both episodic and semantic memory, as reflected by the mix of semantic and episodic elements in descriptions of spontaneous thoughts, as well as semantic priming effects in spontaneous thoughts. We integrate the current evidence based on the interplay between cues and semantic activation. Namely, we suggest that cues are key to access episodic memory and modulate the frequency of spontaneous thought, while semantic activation modulates the content of spontaneous thought. Secondly, we propose that spontaneous retrieval is a privileged area to explore the question of functional independence between systems, because it provides direct access to the episodic system. We review the evidence for spontaneous thought in semantic dementia, which suggests that episodic and semantic systems are functionally independent. We acknowledge the scarcity of evidence and suggest that future studies examine the contents of spontaneous thought descriptions and their neural correlates to test the functional relationship and inform the interaction between episodic and semantic systems.

Spontaneous and deliberate future thinking: a dual process account

In this article, we address an apparent paradox in the literature on mental time travel and mind-wandering: How is it possible that future thinking is both constructive, yet often experienced as occurring spontaneously? We identify and describe two 'routes' whereby episodic future thoughts are brought to consciousness, with each of the 'routes' being associated with separable cognitive processes and functions. Voluntary future thinking relies on controlled, deliberate and slow cognitive processing. The other, termed involuntary or spontaneous future thinking, relies on automatic processes that allows 'fully-fledged' episodic future thoughts to freely come to mind, often triggered by internal or external cues. To unravel the paradox, we propose that the majority of spontaneous future thoughts are 'pre-made' (i.e., each spontaneous future thought is a re-iteration of a previously constructed future event), and therefore based on simple, well-understood, memory processes. We also propose that the pre-made hypothesis explains why spontaneous future thoughts occur rapidly, are similar to involuntary memories, and predominantly about upcoming tasks and goals. We also raise the possibility that spontaneous future thinking is the default mode of imagining the future. This dual process approach complements and extends standard theoretical approaches that emphasise constructive simulation, and outlines novel opportunities for researchers examining voluntary and spontaneous forms of future thinking.

Inducing positive involuntary mental imagery in everyday life: an experimental investigation

Positive involuntary mental imagery occurs frequently in daily life but evidence as to its functions and importance is largely indirect. The current study investigated a method to induce positive involuntary imagery in daily life, which would allow direct testing of its impact. An unselected student sample (N = 80) completed a single session of a positive imagery cognitive bias modification (CBM) paradigm, which involved listening to and imagining brief positive imagery scripts. Participants then recorded any involuntary memories of the imagined training scenarios in a three-day diary before returning to the lab for a follow-up assessment. Participants were randomised to imagine the scenarios in either an emotionally involved or emotionally detached manner, providing a test of the role of emotion in the subsequent experience of involuntary memories. Participants reported experiencing involuntary memories of the training scenarios in their daily life, but the number recorded did not differ between the experimental conditions. Exploratory analyses suggested that more vivid imagery and recall testing were associated with a greater number of involuntary memories. The study highlights the potential of the imagery CBM paradigm to further our understanding of the functions and potential importance of positive involuntary mental imagery in daily life.

Intrusions related to indirectly experienced events in clinical offspring of World War Two survivors

Negative events may not only linger on in the form of intrusive memories in the minds of those directly exposed but also in those who are only indirectly confronted with these events. The aim of the present study was to investigate if intrusions referring to indirectly experienced traumatic events do indeed occur, and to compare their frequency and characteristics to intrusions about directly experienced negative events. Participants (N = 98) were adult postwar offspring of World War Two survivors currently in treatment in one of two clinics specialized in the treatment of war victims. We examined the frequency and characteristics of intrusions about indirectly experienced (i.e., parent war-related) events and two types of directly (self-) experienced events: Self-experienced traumatic events and negative events related to participants' upbringing. Intrusions referring to indirectly experienced traumatic events did indeed occur. The frequency as well as other characteristics of these intrusions did not differ from those of both types of intrusions about directly experienced events. The similarities between intrusions related to different types of events emphasize the (re)constructive nature of memory. Our findings indicate that traumatic events not only affect those directly involved but may also continue to plague the next generation.

Zooming In and Out on One's Life: Autobiographical Representations at Multiple Time Scales

The ability to decouple from the present environment and explore other times is a central feature of the human mind. Research in cognitive psychology and neuroscience has shown that the personal past and future is represented at multiple timescales and levels of resolution, from broad lifetime periods that span years to short-time slices of experience that span seconds. Here, I review this evidence and propose a theoretical framework for understanding mental time travel as the capacity to flexibly navigate hierarchical layers of autobiographical representations. On this view, past and future thoughts rely on two main systems-event simulation and autobiographical knowledge-that allow us to represent experiential contents that are decoupled from sensory input and to place these on a personal timeline scaffolded from conceptual knowledge of the content and structure of our life. The neural basis of this cognitive architecture is discussed, emphasizing the possible role of the medial pFC in integrating layers of autobiographical representations in the service of mental time travel.

Involuntary autobiographical memories and future projections in social anxiety

Intrusive involuntary memories and images are a cardinal phenomenon in a range of psychological disorders, but not systematically examined in social anxiety. We examined potential biases upon generating involuntary versus voluntary memories and future projections in individuals with high and low levels of social anxiety. Participants recorded involuntary and voluntary autobiographical events, and their associated emotional response in a structured mental time travel diary. High social anxiety was associated with more intense anxiety and embarrassment and greater use of a range of emotion regulation strategies upon generating all types of autobiographical events. Involuntary (versus voluntary) memories and future events were associated with a heightened emotional response independent of social anxiety, and memories were associated with more embarrassment than imagined future events. The effects of high versus low social anxiety and involuntary versus voluntary generation process were independent from each other. The findings have implications for affective and cognitive models of involuntary memories and future projections in emotional disorders.

Event Representations and Predictive Processing: The Role of the Midline Default Network Core

The human brain is tightly coupled to the world through its sensory‐motor systems—but it also spends a lot of its metabolism talking to itself. One important function of this intrinsic activity is the establishment and updating of event models—representations of the current situation that can predictively guide perception, learning, and action control. Here, we propose that event models largely depend on the default network (DN) midline core that includes the posterior cingulate and anterior medial prefrontal cortex. An increasing body of data indeed suggests that this subnetwork can facilitate stimuli processing during both naturalistic event comprehension and cognitive tasks in which mental representations of prior situations, trials, and task rules can predictively guide attention and performance. This midline core involvement in supporting predictions through event models can make sense of an otherwise complex and conflicting pattern of results regarding the possible cognitive functions subserved by the DN.

Stawarczyk, Bezdek, and Zacks offer neuroscience evidence for a midline default network core, which appears to coordinate internal, top‐down mentation with externally‐triggered, bottom‐up attention in a push‐pull relationship. The network may enable the flexible pursuance of thoughts tuned into or detached from the current environment.

Spontaneous future cognition: the past, present and future of an emerging topic

In this Editorial, we discuss the past, present and future of an emerging and fast-developing field-spontaneous future cognition. In tracking the past of this research, the trajectories of research on mind-wandering, episodic future thinking and prospective memory are briefly examined, and their relation with spontaneous future cognition demarcated. Three broad methodological approaches (questionnaire, naturalistic and laboratory) used to study spontaneous future thoughts are described, providing an overview of the field. The present state of this research is represented by a themed analysis of the articles included in this Special Issue. The breadth of studies (covering cognitive mechanisms, developmental stages and psychopathology) have already led to important insights, especially concerning the conditions in which spontaneous future thoughts most commonly arise and who may be predisposed to experiencing them. In the future, greater effort should focus on developing a theoretical account of spontaneous future cognition-this may increase our understanding of how and why spontaneous future thoughts occur. If future research in this area reflects the diversity and depth within this Special Issue, a flourishing of research on spontaneous future cognition will be on the horizon in years or perhaps decades to come.

The tendency for experiencing involuntary future and past mental time travel is robustly related to thought suppression: an exploratory study

Involuntary mental time travel (MTT) refers to projecting oneself into the past or into the future without prior conscious effort. The previous studies have shown high inter-individual variability in the frequency of involuntary MTT, but a few systematic studies exist. In three exploratory studies, we investigated the relation between individual differences in experiencing involuntary past and future MTT, and selected emotional and cognitive processes, with a special focus on thought suppression. Across all three studies, thought suppression emerged as a robust predictor of involuntary MTT above and beyond emotion-related variables, mind-wandering, daydreaming styles, and demographic variables. Findings from Studies 1 and 2 showed that higher thought suppression consistently predicted both more frequent involuntary past and future MTT across an American and a Danish sample, whereas rumination and emotion regulation were less consistently related to involuntary MTT. In Study 3, thought suppression reliably predicted more frequent involuntary MTT, even when controlling for mind-wandering, as well as for positive and negative daydreaming styles, which were all related to greater involuntary MTT. Overall, the individual differences assessed showed similar relationships to the tendency for having past and future involuntary MTT, with the possible exception of daydreaming styles, which appeared more strongly related to future-directed involuntary MTT.