The traces of imagination: early attention bias toward positively imagined stimuli

To imagine our future can be a source of motivation. Mental imagery, an internally generated perceptual experience, has long been thought to drive and guide behavior by representing a desired goal (McMahon, 1973). In the treatment of psychological disorders, these properties of mental imagery may prove useful to promote adaptive behaviors (Renner et al., 2021). By imagining the positive emotional impact of prospective activities, reward anticipation may be strengthened and, in turn, motivate behavioral engagement (Renner et al., 2021; Rösch et al., 2021).

Previous work has shown that mental imagery has the capacity to evoke emotions on a subjective, physiological and neural level (Holmes & Mathews, 2010; Ji et al., 2016). Mental imagery relies on similar neural processes as perception and, thus, is thought to function as a simulation of reality inducing similar emotional and behavioral responses (Dijkstra et al., 2019, 2021; Ji et al., 2016; Lang, 1978; Sambuco et al., 2020). Indeed, multiple experiments have demonstrated that imagining emotional (positive and negative) events increases emotional engagement more than imagining neutral events (Brandi et al., 2021; Henderson et al., 2018) or thinking about emotional events verbally (Holmes et al., 2006, 2008; Nelis et al., 2015). On a physiological level, mental imagery of emotional compared to neutral events further has been associated with enhanced pupil dilation, reflecting higher levels of emotional arousal (Henderson et al., 2018). This is mirrored by evidence suggesting that the inability to perform visual imagery while reading emotional imagery-provoking scenarios (i.e. verbal-focused processing) is related to a lack of emotional arousal, evidenced by an attenuated skin conductance response (Wicken et al., 2021). Likewise, neural activation in emotion processing brain regions, such as the ventromedial prefrontal cortex and striatum, has been shown to scale with the affective value of imagined experiences (Benoit et al., 2014; Lee et al., 2021). Together, these findings highlight a unique relation between mental imagery and emotion. Imagining the positive emotional impact of engaging in activities, thus, may be well suited to amplify behavioral motivation.

Recent studies have focused on the use of positive imagery to promote behavioral motivation. In these studies, individuals were asked to schedule and then imagine performing everyday activities, focusing on the most positive aspects of the activities (Heise et al., 2022; Ji et al., 2021; Renner et al., 2019). Compared to individuals who were asked to only schedule activities (without mental imagery) or to imagine the process of performing activities (without a focus on positive aspects), individuals who positively imagined performing the activities reported greater anticipatory pleasure (i.e. pleasure experienced when imagining the activity), anticipated pleasure (i.e. pleasure expected to be experienced when performing the activity) and behavioral motivation. However, in contrast to performing a verbal-reasoning task, mental imagery only increased anticipatory pleasure but not anticipated pleasure and behavioral motivation (Ji et al., 2021). Further support for the motivational effect of mental imagery is provided by Hallford et al. (2020), who showed that nominating and imagining upcoming positive events enhances ratings of pleasant anticipation and behavioral intention relative to baseline. A study by Linke and Wessa (2017) corroborates these findings on a more implicit level. Compared to a waitlist control condition, the authors found faster approach tendencies toward positive activities following a 2-week mental imagery training during which participants imagined activities they found personally enjoyable. This also fits well with the work by Oettingen (2014) showing that imagining personal goals and how to achieve them increases behavioral motivation. Thus, initial evidence indeed suggests that positive imagery of everyday activities promotes behavioral motivation.

To use the increase in behavioral motivation through positive imagery to promote adaptive behaviors effectively, a more in depth understanding of the involved cognitive mechanisms is important. For behavioral motivation to give rise to motivated behavior, activities first need to be attended to. The role of attention in motivated behavior, however, has not yet been thoroughly investigated in this context. A meta-analytic review by Pool et al. (2016) showed that positive stimuli attract attention especially during the early stages of attentional processing. Also referred to as motivated attention (Lang et al., 1997), this type of attention bias has been seen for positive stimuli as well as for neutral stimuli with an acquired positive value (Pool et al., 2016). The latter, for instance, has been shown to increase visual search efficiency when it serves as the target and to decrease it when it serves as the distractor (Anderson & Yantis, 2012; Kristjánsson et al., 2010). Interestingly, visual attention can be biased regardless of whether stimulus-reward pairings are previously trained or merely instructed without additional training (Tibboel & Liefooghe, 2020). Paulus et al. (2022) further demonstrated that vividly imagining an interaction with liked or disliked people at neutral places shapes individuals’ attitudes toward the places in the respective direction. This imagery-based evaluative conditioning (Hofmann et al., 2010) may also take place during positive imagery of prospective activities, during which activities are associated with positive emotions. Positively imagined activities could, thus, be expected to gain attentional priority due to their increase in positive value.

This study examined the influence of positive imagery of everyday activities on attention using a visual probe task with concurrent eye tracking. Results showed that positive compared to neutral imagery increases self-reported behavioral motivation and biases the direction, but not the duration, of gaze on objects associated with the imagined activities. A post-hoc analysis revealed that the observed direction bias was more pronounced in individuals with greater depressive symptom severity. However, no evidence was found to suggest that the direction bias was related to subjective reports of behavioral motivation.

Imagining the positive emotional impact of performing an activity relative to a neutral circumstance of the activity shifted early attention, but not sustained attention, toward objects involved in the imagined activity. This is in line with Pool et al. (2016), who showed that positive stimuli attract attention especially during the early stages of attentional processing. It has been suggested that this is because desired stimuli attract attention automatically without conscious awareness (Frankland et al., 2016; Theeuwes, 2010; Theeuwes & Belopolsky, 2012). The lack of evidence for sustained attention on positively imagined objects, thus, could indicate that the positive imagery manipulation was not strong enough to influence a conscious evaluation of the stimuli at a later point in time. As predicted, however, positively imagined objects appear to have captured early attention due to an increase in positive value. This is in line with recent work suggesting that mental imagery can affect the evaluation of real-life environments (Benoit et al., 2019; Paulus et al., 2022). Paulus et al. (2022), as mentioned previously, demonstrated that imagining an interaction with liked or disliked individuals at an initially neutral place changes a person’s attitude toward that place in the respective direction. This imagery-based evaluative conditioning (Hofmann et al., 2010) could, thus, explain the present findings. The positive valence of emotions experienced during positive imagery (unconditioned stimulus) might have transferred to the simultaneously depicted objects (conditioned stimulus), thereby increasing their saliency during the subsequent visual probe task. Activities imagined in a positive compared to a neutral manner, indeed, were evaluated more positively by participants. They gave higher ratings of reward experienced during the positive imagery as well as higher ratings of anticipated reward and motivation to perform the activities. However, no evidence was found to suggest that these subjective reports were associated with the observed bias in initial orientation. It has been previously argued that early attention as opposed to sustained attention occurs independent of conscious awareness (Frankland et al., 2016; Theeuwes, 2010; Theeuwes & Belopolsky, 2012). In keeping with this, self-report measures assessing the reflection of performance (explicit processing) and behavioral measures assessing performance itself (implicit processing) do not always correspond (Dang et al., 2020). This could explain why behavioral motivation and early attention were not related in the present study. However, temporary goals have been argued to influence automatic attention processes (Vogt et al., 2020). A recent meta-analytic review by Hardman et al. (2021) further suggested that state motivation is a key determinant of attention bias for appetitive (food) stimuli. Contrary to this, in the present study, motivation was assessed specifically for each stimulus rather than as a general motivational state of the individual. Moreover, it is possible that the difference in inherent (food) versus acquired (objects associated with positive imagery) motivational value of stimuli might play an important role. It may also be that participants memorized objects imagined in a positive manner better than objects imagined in a neutral manner. Previous work, indeed, has shown a memory benefit for emotional compared to neutral material (Kensinger & Corkin, 2003). As reward associations can magnify the effect of memory on attention already in the early stages of perceptual processing (Doallo et al., 2013), the observed shift in early attention could also be explained by a better memory of positively imagined objects. Although more research is needed to fully understand the lack of relation between behavioral motivation and early attention in this context, this study highlights the potential of positive imagery to increase behavioral motivation and shift early attention toward activities through an increase in positive value.

Directing attention using positive imagery may prove useful to motivate the engagement in adaptive behaviors. Indeed, enhancing the saliency of (monetary) rewards has been recently found to increase motivated behavior in an effort-based decision-making task (Renz et al., 2021). Similarly, in real-life behavioral contexts, shifting early attention toward healthy food and lifestyle choices has been found to positively influence motivational approach (Suri & Gross, 2015). This is particularly interesting in light of clinical interventions aiming to promote behavioral activation. Here, positive imagery has been proposed as a motivational amplifier addressing reward anticipation deficits in depression (Renner et al., 2019, 2021). Previous research has suggested that these deficits in reward anticipation are the primary factor for reduced reward-motivated behavior (Bakker et al., 2017; Gorka et al., 2014; Sherdell et al., 2012). Moreover, depression has been associated with difficulties in the prioritization of environmental stimuli (Whitton et al., 2015). By shifting early attention toward environmental stimuli predictive of reward, positive imagery, thus, may be well suited to target these deficits in depression. Indeed, in the present study, individuals with greater depressive symptom severity were more susceptible to the positive imagery manipulation and showed a more pronounced shift in early attention. This further signifies the applicability of positive imagery in the context of depression.

The present study elucidates early attention as a cognitive mechanism affected by positive imagery. As early attention plays an important role in motivated behavior, applying positive imagery to increase the saliency of adaptive behaviors in the environment may be a valuable instrument to promote behavioral activation. One potential target group for this treatment are individuals with depressive symptoms, as they appear to be especially susceptible to positive imagery.