Mentally Simulate Research Articles

Mental Simulation as Substitute for Experience

AbstractPeople spend a considerable amount of their time mentally simulating experiences other than the one in which they are presently engaged, as a means of distraction, coping, or preparation for the future. In this integrative review, we examine four (non‐exhaustive) cases in which mentally simulating an experience serves a different function, as a substitute for the corresponding experience. In each case, mentally simulating an experience evokes similar cognitive, physiological, and/or behavioral consequences as having the corresponding experience in reality: (i) imagined experiences are attributed evidentiary value like physical evidence, (ii) mental practice instantiates the same performance benefits as physical practice, (iii) imagined consumption of a food reduces its actual consumption, and (iv) imagined goal achievement reduces motivation for actual goal achievement. We organize these cases under a common superordinate category and discuss their different methodological approaches and explanatory accounts. Our integration yields theoretical and practical insights into when and why mentally simulating an experience serves as its substitute.

Effectiveness of a brief intervention using process-based mental simulations in promoting muscular strength in physical education

This study examined the effectiveness of a brief theory-based intervention on muscular strength among adolescents in a physical education setting. The intervention adopted a process-based mental simulation technique. The self-reported frequency of practising for and actual levels of abdominal muscular strength/endurance as one component of health-related physical fitness was targeted. Adolescents aged 16–19 years ( n = 105) from nine classes were cluster-randomly assigned to experimental, mere-measurement control, and no-measurement control groups. All participants performed the one-minute sit-up test at baseline and four weeks later to measure their abdominal muscular strength/endurance. In the middle of the four-week period, participants allocated to the experimental group mentally simulated the process (i.e. practising) for doing better on the follow-up test relative to the baseline. Results revealed a significant effect of the process mental simulation on test performance at follow-up, but no effect on self-reported frequency of practising for the follow-up test. There was no evidence for the mediation of the effect of process mental simulation on test performance by planning, motivation, or anxiety variables. Results supported the effectiveness of the process mental simulation intervention in enhancing muscular strength among adolescents in a physical education setting, but not in promoting frequency of practise. The latter may be due to the process mental simulation not increasing the frequency but rather the quality of practising. This knowledge could help physical education teachers to facilitate adolescents’ endeavours in improving their muscular strength as one component of health-related physical fitness.

When do language comprehenders mentally simulate locations?

Abstract Embodied approaches to comprehension propose that understanding language entails performing mental simulations of its content. The evidence, however, is mixed. Action-sentence Compatibility Effect studies (Glenberg and Kaschak 2002) report mental simulation of motor actions during processing of motion language. But the same studies find no evidence that language comprehenders perform spatial simulations of the corresponding locations. This challenges simulation-based approaches. If locations are not represented in simulation, but are still understood, then simulation may be unnecessary for understanding. We conducted a Location-sentence Compatibility experiment, to determine whether understanders mentally simulate locations. People did indeed simulate locations, but only when sentences used progressive (and not perfect) grammatical aspect. Moreover, mental simulations of locations differed for language about concrete versus abstract events. These findings substantiate the role of mental simulation in language understanding, while highlighting the importance of the grammatical form of utterances as well as their content.

Mental simulation and experience as determinants of performance expectancies in people with schizophrenia spectrum disorder

People with schizophrenia demonstrate both impairment in mental time travel and reduced expectancies of performance on future tasks. We aimed to reconcile these findings within the Kahneman and Tversky (1982) simulation heuristic framework by testing a key prediction that impaired future simulation would be associated with reduced performance expectancies in people with schizophrenia spectrum disorder (SZSPEC). A total of 54 individuals (30 people with SZSPEC and 24 healthy controls) generated mental simulations of everyday scenarios; after each response they rated performance expectations, distress and the similarity of the scenario to experience. Independent raters coded the coherence of responses. We found that people with SZSPEC had, compared to healthy controls, lower performance expectations and greater anticipated distress when imaging everyday scenarios. Lower performance expectancies were associated with lower experience of similar scenarios, greater negative symptoms and social withdrawal in the SZSPEC group. The current study confirmed previous findings of both impaired mental simulation and abnormal performance expectations in people with SZSPEC, together with the association of the latter with negative symptoms. Experience with social or occupational activities plays a more important role in determining performance expectancies in people with SS than the ability to mentally simulate scenarios.

Gender differences in mental simulation during sentence and word processing

Text comprehension requires readers to mentally simulate the described situation by reactivating previously acquired sensory and motor information from (episodic) memory. Drawing upon research demonstrating gender differences, favouring girls, in tasks involving episodic memory retrieval, the present study explores whether gender differences exist in mental simulation in children (Grades 4 to 6). In Experiment 1, 99 children performed a sentence–picture verification task measuring mental simulation at sentence level. In Experiment 2, 97 children completed a lexical decision task in which imageability of words was manipulated to measure mental simulation at word level. Only for girls we found faster reaction times for matching versus mismatching sentence–picture pairs (Experiment 1) and high‐imageability versus low‐imageability words (Experiment 2). The results suggest that girls construct more coherent and vivid mental simulations than boys and rely more heavily on these representations. The results emphasize the importance of including gender into reading comprehension research. [Correction added on 13 June 2016, after first online publication: The affiliation of author “Björn B. de Koning” was previously wrong and has been corrected in this current version.]

Body Constraints on Motor Simulation in Autism Spectrum Disorders

Developmental data suggested that mental simulation skills become progressively dissociated from overt motor activity across development. Thus, efficient simulation is rather independent from current sensorimotor information. Here, we tested the impact of bodily (sensorimotor) information on simulation skills of adolescents with Autism Spectrum Disorders (ASD). Typically-developing (TD) and ASD participants judged laterality of hand images while keeping one arm flexed on chest or while holding both arms extended. Both groups were able to mentally simulate actions, but this ability was constrained by body posture more in ASD than in TD adolescents. The strong impact of actual body information on motor simulation implies that simulative skills are not fully effective in ASD individuals.

A Neural Architecture for Performing Actual and Mentally Simulated Movements During Self-Intended and Observed Bimanual Arm Reaching Movements

Dexterous reaching, pointing, and grasping play a critical role in human interactions with tools and the environment, and it also allows individuals to interact with one another effectively in social settings. Developing robotic systems with mental simulation and imitation learning abilities for such tasks seems a promising way to enhance robot performance as well as to enable interactions with humans in a social context. In spite of important advances in artificial intelligence and smart robotics, current robotic systems lack the flexibility and adaptability that humans so naturally exhibit. Here we present and study a neural architecture that captures some critical visuo-spatial transformations that are required for the cognitive processes of mental simulation and imitation. The results show that our neural model can perform accurate, flexible and robust 3D unimanual and bimanual actual/imagined reaching movements while avoiding extreme joint positions and generating kinematics similar to those observed with humans. In addition, using visuo-spatial transformations, the neural model was able to observe/imitate bimanual arm reaching movements independently of the viewpoint, distance and anthropometry between the demonstrator and imitator. Our model is a first step towards developing a more advanced neurally-inspired hierarchical architecture that integrates mental simulation and sensorimotor processing as it learns to imitate dexterous bimanual arm movements.

Tool use imagery triggers tool incorporation in the body schema.

Tool-use has been shown to modify the way the brain represents the metrical characteristics of the effector controlling the tool. For example, the use of tools that elongate the physical length of the arm induces kinematic changes affecting selectively the transport component of subsequent free-hand movements. Although mental simulation of an action is known to involve -to a large extent- the same processes as those at play in overt motor execution, whether tool-use imagery can yield similar effects on the body representation remains unknown. Mentally simulated actions indeed elicit autonomic physiological responses and follow motor execution rules that are comparable to those associated with the correspondent overt performance. Therefore, here we investigated the effects of the mental simulation of actions performed with a tool on the body representation by studying subsequent free-hand movements. Subjects executed reach to grasp movements with their hand before and after an imagery task performed with either a tool elongating their arm length or, as a control, with their hand alone. Two main results were found: First, in agreement with previous studies, durations of imagined movements performed with the tool and the hand were similarly affected by task difficulty. Second, kinematics of free-hand movements was affected after tool-use imagery, but not hand-use imagery, in a way similar to that previously documented after actual tool-use. These findings constitute the first evidence that tool-use imagery is sufficient to affect the representation of the user's arm.

Using imagery perspective to access two distinct forms of self-knowledge: Associative evaluations versus propositional self-beliefs.

When mentally simulating life events, people may visualize them from either an actor's 1st-person or observer's 3rd-person visual perspective. Two experiments demonstrated that visual perspective differentially determines reliance on 2 distinct forms of self-knowledge: associative evaluations of the simulated environment and propositional self-beliefs about relevant values and preferences. Implicit measures indexed associative evaluations of environmental stimuli (political candidates, outgroups); explicit measures indexed propositional self-beliefs about relevant personal values or preferences. A separate session manipulated participants' visual perspective for mentally simulating a pertinent event (voting, interracial interaction) as they forecasted their behavior or feelings if that event occurred. Forecasts corresponded more closely with associative evaluations from the 1st-person than 3rd-person perspective but more closely with propositional self-beliefs from the 3rd-person than 1st-person. Results have practical implications for channeling the power of mental simulation to desired ends and theoretical implications for understanding the pathways by which imagery and mental simulation shape cognition.

Discriminating Taxonomic Categories and Domains in Mental Simulations of Concepts of Varying Concreteness

Most studies of conceptual knowledge in the brain focus on a narrow range of concrete conceptual categories, rely on the researchers' intuitions about which object belongs to these categories, and assume a broadly taxonomic organization of knowledge. In this fMRI study, we focus on concepts with a variety of concreteness levels; we use a state of the art lexical resource (WordNet 3.1) as the source for a relatively large number of category distinctions and compare a taxonomic style of organization with a domain-based model (an example domain is Law). Participants mentally simulated situations associated with concepts when cued by text stimuli. Using multivariate pattern analysis, we find evidence that all Taxonomic categories and Domains can be distinguished from fMRI data and also observe a clear concreteness effect: Tools and Locations can be reliably predicted for unseen participants, but less concrete categories (e.g., Attributes, Communications, Events, Social Roles) can only be reliably discriminated within participants. A second concreteness effect relates to the interaction of Domain and Taxonomic category membership: Domain (e.g., relation to Law vs. Music) can be better predicted for less concrete categories. We repeated the analysis within anatomical regions, observing discrimination between all/most categories in the left mid occipital and left mid temporal gyri, and more specialized discrimination for concrete categories Tool and Location in the left precentral and fusiform gyri, respectively. Highly concrete/abstract Taxonomic categories and Domain were segregated in frontal regions. We conclude that both Taxonomic and Domain class distinctions are relevant for interpreting neural structuring of concrete and abstract concepts.

Dominant vs. nondominant arm advantage in mentally simulated actions in right handers

Although plentiful data are available regarding mental states involving the dominant-right arm, the evidence for the nondominant-left arm is sparse. Here, we investigated whether right-handers can generate accurate predictions with either the right or the left arm. Fifteen adults carried out actual and mental arm movements in two directions with varying inertial resistance (inertial anisotropy phenomenon). We recorded actual and mental movement times and used the degree of their similarity as an indicator for the accuracy of motor imagery/prediction process. We found timing correspondences (isochrony) between actual and mental right arm movements in both rightward (low inertia resistance) and leftward (high inertia resistance) directions. Timing similarities between actual and mental left arm movements existed for the leftward direction (low inertia resistance) but not for the rightward direction (high inertia resistance). We found similar results when participants reaching towards the midline of the workspace, a result that excludes a hemispace effect. Electromyographic analysis during mental movements showed that arm muscles remained inactivate, thus eliminating a muscle activation strategy that could explain intermanual differences. Furthermore, motor-evoked potentials enhancement in both right and left biceps brachii during mental actions indicated that subjects were actively engaged in mental movement simulation and that the disadvantage of the left arm cannot be attributed to the nonactivation of the right motor cortex. Our findings suggest that predictive mechanisms are more robust for the right than the left arm in right-handers. We discussed these findings from the perspective of the internal models theory and the dynamic-dominance hypothesis of laterality.

When the left hand does not know what the left hand is doing: response mode affects mental rotation of hands

Mentally simulating a movement is known to share temporal and kinematic characteristics with the execution of the same movement, and this is thought to be reflected in the sharing of neural resources between the two activities. A powerful method of implicitly facilitating such mental simulation (or motor imagery) in individuals is to present them with a picture of a hand and ask them to identify its laterality (i.e. left or right). The mental rotation undertaken in order to complete this hand laterality recognition task (HLRT) provides an effective form of motor imagery, and the task has become an influential tool in clinical and experimental studies. However, performance on the task is modified by numerous factors, and there is a suggestion that the method of response demanded by different versions of the task may have a modulating effect. Here, we compared performance on the HLRT when responding verbally or manually in a group of unimpaired right-handed participants. For manual responses, we also compared performance when participants responded unimanually, using the index and middle fingers of their dominant or non-dominant hand. Performance was poorer for the manual compared to the verbal condition both in terms of accuracy and response time. Furthermore, for manual responses, the requirement to make a response with a specific limb selectively disrupted the ability to recognise an image of the corresponding limb. The disruption is considered to reflect difficulty in concurrently planning two actions with the same limb (manual response and mental rotation). Implications for the interpretation of existing and future studies are discussed.

The case of the missing pronouns: Does mentally simulated perspective play a functional role in the comprehension of person?

Language comprehenders can mentally simulate perceptual and motor features of scenes they hear or read about (Barsalou, 1999; Glenberg & Kaschak, 2002; Zwaan, Stanfield, & Yaxley, 2002). Recent research shows that these simulations adopt a particular perspective (Borghi, Glenberg, & Kaschak, 2004; Brunyé, Ditman, Mahoney, Augustyn, & Taylor, 2009). Moreover, features of utterances influence the perspective that comprehenders are led to adopt. For instance, language about you primes a participant visual perspective, while third person he and she prime an observer perspective. But what role does perspectival mental simulation play in the comprehension of person? On the one hand, the different perspectives adopted during language understanding could be necessary for successfully determining the meaning of an utterance. However, current empirical evidence is also compatible with the possibility that adopting a perspective in mental simulation is not essential to comprehending who did what to whom. If the latter is the case, then we should be able to find cases where language comprehenders understand who did what to whom without measurably performing mental simulation from a particular perspective. A candidate language that might display such a case is Japanese, where grammatical subject pronouns can be omitted when the subject is inferable from context. We replicated a previously used method for assessing perspectival mental simulation during language comprehension, but tailored it to Japanese. The results showed that when pronouns were present, like in English, sentences facilitated identification of an image matching the proposed perspective associated with the mentioned pronoun. This replicated the previous finding for English. But when the subject pronoun was omitted, so that the sentence did not explicitly mention the subject, there was no such effect. Nonetheless, native comprehenders of Japanese automatically and easily tracked who the subjects of the sentences with omitted subjects were. Together, these findings suggest that while grammatical person modulates visual perspective in mental simulation, visual perspective is not necessary for successful identification and representation of event participants.

The Mixed Instrumental Controller: Using Value of Information to Combine Habitual Choice and Mental Simulation

Instrumental behavior depends on both goal-directed and habitual mechanisms of choice. Normative views cast these mechanisms in terms of model-free and model-based methods of reinforcement learning, respectively. An influential proposal hypothesizes that model-free and model-based mechanisms coexist and compete in the brain according to their relative uncertainty. In this paper we propose a novel view in which a single Mixed Instrumental Controller produces both goal-directed and habitual behavior by flexibly balancing and combining model-based and model-free computations. The Mixed Instrumental Controller performs a cost-benefits analysis to decide whether to chose an action immediately based on the available “cached” value of actions (linked to model-free mechanisms) or to improve value estimation by mentally simulating the expected outcome values (linked to model-based mechanisms). Since mental simulation entails cognitive effort and increases the reward delay, it is activated only when the associated “Value of Information” exceeds its costs. The model proposes a method to compute the Value of Information, based on the uncertainty of action values and on the distance of alternative cached action values. Overall, the model by default chooses on the basis of lighter model-free estimates, and integrates them with costly model-based predictions only when useful. Mental simulation uses a sampling method to produce reward expectancies, which are used to update the cached value of one or more actions; in turn, this updated value is used for the choice. The key predictions of the model are tested in different settings of a double T-maze scenario. Results are discussed in relation with neurobiological evidence on the hippocampus – ventral striatum circuit in rodents, which has been linked to goal-directed spatial navigation.

Imagined sensory experiences can shape person perception: It's a matter of visual perspective

Psychological warmth serves as a fundamental dimension of human social cognition. From impressions of strangers to appraisals of groups, assessments of warmth (vs. coldness) comprise an elemental building block of social perception. Using embodiment as a guiding framework, research has demonstrated that perceptions of others along the warm-cold dimension can be elicited by sensory experiences (e.g., physical warmth). Here we show that effects of this kind can also be triggered by mentally simulating physical temperature, but only under certain theoretically important imagery conditions. Specifically, impressions of a target were impacted by imagined warmth or coldness (i.e., thinking about holding a cup of hot/iced coffee) only when an event was simulated from an egocentric (i.e., first-person) perspective. No such effect emerged when an allocentric (i.e., third-person) orientation was adopted. This finding underscores the functional nature of mental simulation and identifies spatial visual perspective as a critical boundary condition of embodied cognition.

How mindset influences self-efficacy beliefs and unhealthy snacking

An effective strategy for improving diet is making plans for how to cope with future tempting situations. It is helpful to mentally simulate future tempting situations, i.e. “high-risk situations”, to construct effective coping plans and prevent lapses (Marlatt & Gordon, 1985)[[Au: The reference “Marlatt and Gordon (1985)” is cited in the text but not listed. Please check.]]. Many people, however, overestimate their ability to resist temptation during mental simulation, resulting in ineffective coping plans. The present study aimed to examine whether consideration of different aspects of future situations during coping planning influence self-beliefs and subsequent enactment of plans. Participants either focused on factors preceding succumbing to temptation (process mindset, e.g. boredom) vs. factors resulting from succumbing (outcome mindset, e.g. guilt), after which they reported self-efficacy beliefs, and kept a snack diary for one week to measure subsequent goal-congruent behavior. Results show that those considering the outcome (vs. process) had higher self-efficacy beliefs and consumed fewer unhealthy snacks. Thinking about negative consequences of goal-inconsistent behavior may be a powerful tool to elicit persistence and renewed efforts to goal attainment. It is concluded that high self-efficacy beliefs – whether realistic or not – may be self-fulfilling in the context of healthy eating. This conclusion counteracts the idea that inflated self-efficacy beliefs have detrimental consequences for enacting goal-directed behavior (Nordgren et al., 2009)[[Au: The reference “Nordgren et al. (2009)” is cited in the text but not listed. Please check.]].

Effect of levodopa on both verbal and motor representations of action in Parkinson’s disease: A fMRI study

Previous studies have demonstrated that non-demented Parkinson’s disease (PD) patients have a specific impairment of verb production compared with noun generation. One interpretation of this deficit suggested the influence of striato-frontal dysfunction on action-related verb processing. The aim of our study was to investigate cerebral changes after motor improvement due to dopaminergic medication on the neural circuitry supporting action representation in the brain as mediated by verb generation and motor imagery in PD patients. Functional magnetic resonance imaging on 8 PD patients in “ON” dopaminergic treatment state (DTS) and in “OFF” DTS was used to explore the brain activity during three different tasks: Object Naming (ObjN), Generation of Action Verbs (GenA) in which patients were asked to overtly say an action associated with a picture and mental simulation of action (MSoA) was investigated by asking subjects to mentally simulate an action related to a depicted object. The distribution of brain activities associated with these tasks whatever DTS was very similar to results of previous studies. The results showed that brain activity related to semantics of action is modified by dopaminergic treatment in PD patients. This cerebral reorganisation concerns mainly motor and premotor cortex suggesting an involvement of the putaminal motor loop according to the “motor” theory of verb processing.

The “Visual Depiction Effect” in Advertising: Facilitating Embodied Mental Simulation through Product Orientation

This research demonstrates that visual product depictions within advertisements, such as the subtle manipulation of orienting a product toward a participant’s dominant hand, facilitate mental simulation that evokes motor responses. We propose that viewing an object can lead to similar behavioral consequences as interacting with the object since our minds mentally simulate the experience. Four studies show that visually depicting a product that facilitates more (vs. less) embodied mental simulation results in heightened purchase intentions. The studies support our proposed embodied mental simulation account. For instance, occupying the perceptual resources required for embodied mental simulation attenuates the impact of visual product depiction on purchase intentions. For negatively valenced products, facilitation of embodied mental simulation decreases purchase intentions.

Effect of volitional relaxation and motor imagery on F wave and MEP: Do these tasks affect excitability of the spinal or cortical motor neurons?

Objective To test if simple motor imagery, like thumb abduction, preferentially influences the excitability of the spinal or cortical motoneurons. Methods Ten healthy subjects underwent two separate experiments, each consisting of recording F waves and MEPs from abductor pollicis brevis (APB) in three consecutive sessions: (1) baseline, (2) after immobilizing APB for 3 h, and (3) after brief muscle exercise. During the immobilization, the subjects were instructed to volitionally relax APB in experiment 1 (relaxation task), and mentally simulate thumb abduction without actual movement in experiment 2 (imagery task). Results Relaxation task suppressed both MEPs and F waves. Motor imagery reduced this suppression, restoring F waves nearly completely (94%) and MEPs only partially (77%). Hence, the rest-induced decline of MEPs in part results from cortical modulation. In contrast, statistical analysis revealed no differences in imagery-induced recovery of motoneuron excitabilities whether assessed by F wave or MEP. Thus, increased excitability of spinal motoneurons responsible for F-wave changes also accounts for recovery of MEPs. Conclusions Volitional relaxation depresses the spinal and cortical motoneurons, whereas mental simulation counters rest-induced suppression primarily by restoring spinal excitability. Significance The present findings help elucidate physiologic mechanisms underlying motor imagery.

Blind ethics: Closing one’s eyes polarizes moral judgments and discourages dishonest behavior

Four experiments demonstrate that closing one’s eyes affects ethical judgment and behavior because it induces people to mentally simulate events more extensively. People who considered situations with their eyes closed rather than open judged immoral behaviors as more unethical and moral behaviors as more ethical. In addition, considering potential decisions with closed eyes decreased stated intentions to behave ethically and actual self-interested behavior. This relationship was mediated by the more extensive mental simulation that occurred with eyes closed rather than open, which, in turn, intensified emotional reactions to the ethical situation. We discuss the implications of these findings for moral psychology and ethical decision making.