Schema-related eye movements support episodic simulation

Internal coupling: Eye behavior coupled to visual imagery

Our eyes do not only respond to visual perception but also to internal cognition involving visual imagery, which can be referred to as internal coupling. This review synthesizes evidence on internal coupling across diverse domains including episodic memory and simulation, visuospatial memory, numerical cognition, object movement, body movement, and brightness imagery. In each domain, eye movements consistently reflect distinct aspects of mental imagery typically akin to those seen in corresponding visual experiences. Several findings further suggest that internal coupling may not only coincide with but also supports internal cognition as evidenced by improved cognitive performance. Available theoretical accounts suggest that internal coupling may serve at least two functional roles in visual imagery: facilitating memory reconstruction and indicating shifts in internal attention. Moreover, recent insights into the neurobiology of internal coupling highlight substantially shared neural pathways in externally and internally directed cognition. The review concludes by identifying open questions and promising avenues for future research such as exploring moderating roles of context and individual differences in internal coupling.

Eye movements reinstate remembered locations during episodic simulation

Imagining the future, like recalling the past, relies on the ability to retrieve and imagine a spatial context. Research suggests that eye movements support this process by reactivating spatial contextual details from memory, a process termed gaze reinstatement. While gaze reinstatement has been linked to successful memory retrieval, it remains unclear whether it supports the related process of future simulation. In the present study, we recorded both eye movements and audio while participants described familiar locations from memory and subsequently imagined future events occurring in those locations while either freely moving their eyes or maintaining central fixation. Restricting viewing during simulation significantly reduced self-reported vividness ratings, supporting a critical role for eye movements in simulation. When viewing was unrestricted, participants spontaneously reinstated gaze patterns specific to the simulated location, replicating findings of gaze reinstatement during memory retrieval. Finally, gaze-based location reinstatement was predictive of simulation success, indexed by the number of internal (episodic) details produced, with both measures peaking early and co-varying over time. Together, these findings suggest that the same oculomotor processes that support episodic memory retrieval - that is, gaze-based reinstatement of spatial context - also support episodic simulation.

Peering into the future: Eye movements predict neural repetition effects during episodic simulation

Imagining future scenarios involves recombining different elements of past experiences into a coherent event, a process broadly supported by the brain's default network. Prior work suggests that distinct brain regions may contribute to the inclusion of different simulation features. Here we examine how activity in these brain regions relates to the vividness of future simulations. Thirty-four healthy young adults imagined future events with familiar people and locations in a two-part study involving a repetition suppression paradigm. First, participants imagined events while their eyes were tracked during a behavioral session. Immediately after, participants imagined events during MRI scanning. The events to be imagined were manipulated such that some were identical to those imagined in the behavioral session while others involved new locations, new people, or both. In this way, we could examine how self-report ratings and eye movements predict brain activity during simulation along with specific simulation features. Vividness ratings were negatively correlated with eye movements, in contrast to an often-observed positive relationship with past recollection. Moreover, fewer eye movements predicted greater involvement of the hippocampus during simulation, an effect specific to location features. Our findings suggest that eye movements may facilitate scene construction for future thinking, lending support to frameworks that spatial information forms the foundation of episodic simulation.

Scene construction in healthy aging - Exploring the interplay between task complexity and oculomotor behaviour

Mounting evidence indicates a close correspondence between episodic memory, mental imagery, and oculomotor behaviour. It remains unclear, however, how oculomotor variables support endogenously driven forms of mental imagery and how this relationship changes across the adult lifespan. In this study we investigated age-related changes in oculomotor signatures during scene construction and explored how task complexity impacts these processes. Younger and cognitively healthy older participants completed a guided scene construction paradigm where scene complexity was manipulated according to the number of elements to be sequentially integrated. We recorded participants' eye movements and collected subjective ratings regarding their phenomenological experience. Overall, older adults rated their constructions as more vivid and more spatially integrated, while also generating more fixations and saccades relative to the younger group, specifically on control trials. Analyses of participants' total scan paths revealed that, in the early stages of scene construction, oculomotor behaviour changed as a function of task complexity within each group. Following the introduction of a second stimulus, older but not younger adults showed a significant decrease in the production of eye movements. Whether this shift in oculomotor behaviour serves a compensatory function to bolster task performance represents an important question for future research.

Looking at Mental Images: Eye-Tracking Mental Simulation During Retrospective Causal Judgment

How do people evaluate causal relationships? Do they just consider what actually happened, or do they also consider what could have counterfactually happened? Using eye tracking and Gaussian process modeling, we investigated how people mentally simulated past events to judge what caused the outcomes to occur. Participants played a virtual ball-shooting game and then-while looking at a blank screen-mentally simulated (a) what actually happened, (b) what counterfactually could have happened, or (c) what caused the outcome to happen. Our findings showed that participants moved their eyes in patterns consistent with the actual or counterfactual events that they mentally simulated. When simulating what caused the outcome to occur, participants moved their eyes consistent with simulations of counterfactual possibilities. These results favor counterfactual theories of causal reasoning, demonstrate how eye movements can reflect simulation during this reasoning and provide a novel approach for investigating retrospective causal reasoning and counterfactual thinking.

A language of episodic thought?

We propose that episodic thought (i.e., episodic memory and imagination) is a domain where the language-of-thought hypothesis (LoTH) could be fruitfully applied. On the one hand, LoTH could explain the structure of what is encoded into and retrieved from long-term memory. On the other, LoTH can help make sense of how episodic contents come to play such a large variety of different cognitive roles after they have been retrieved.

"Look at the future": Maintained fixation impoverishes future thinking

We evaluated the relationship between eye movements and future thinking. More specifically, we evaluated whether maintained fixation could influence cognitive characteristics of future thinking. We invited participants to imagine future events in two conditions: while freely exploring a white wall and while fixating a cross on the wall. Results demonstrated fewer and longer fixations, as well as fewer and shorter saccades during maintained fixation condition than in the free gaze condition. Shorter total amplitude of saccades was also observed during the maintained fixation condition than during the free-gaze condition. Regarding the cognitive characteristics of future thinking, fewer spatiotemporal details and less visual imagery, slower retrieval time, and shorter descriptions were observed for future thinking during maintained fixation than during free-gaze condition. These results demonstrate that maintaining fixation results in an effortful construction of future scenarios. We suggest that maintained fixation limits the cognitive resources that are required for future thinking.