I am a cognitive scientist investigating how prior knowledge shapes human memory and imagination. My research spans two complementary domains: visual memory and counterfactual thinking. Across both areas, I explore how existing knowledge structures—whether as semantic representations or plausibility judgments—profoundly influence how we remember the past and imagine alternatives.
My main research objective is understanding how our knowledge of the world drives visual memory. I am interested in how semantic representations shape different forms of memory: whether maintaining visual stimuli in mind for short periods of time, vividly recalling something, or recognizing it from similar alternatives. Overall, my experimental work reveals that visual memory relies fundamentally on knowledge frameworks that organize visual information according to existing conceptual structures rather than purely sensory qualities.
My research explores the cognitive mechanisms underlying counterfactual thinking—our ability to imagine alternatives to past events. I investigate how plausibility shape different aspects of counterfactual cognition: from phenomenological characteristics such as vividness to later recall. Overall, my experimental work reveals that counterfactual thinking relies fundamentally on plausibility as an organizing principle that structures how we imagine alternative possibilities.
When we perceive a scene, our brain processes various types of visual information simultaneously, ranging from sensory features, such as line orientations and colors, to categorical features, such as objects and their arrangements. Whereas the role of sensory and categorical visual representations in predicting subsequent memory has been studied using isolated objects, their impact on memory for complex scenes remains largely unknown. To address this gap, we conducted an fMRI study in which female and male participants encoded pictures of familiar scenes (e.g., an airport picture) and later recalled them, while rating the vividness of their visual recall. Outside the scanner, participants had to distinguish each seen scene from three similar lures (e.g., three airport pictures). We modeled the sensory and categorical visual features of multiple scenes using both early and late layers of a deep convolutional neural network. Then, we applied representational similarity analysis to determine which brain regions represented stimuli in accordance with the sensory and categorical models. We found that categorical, but not sensory, representations predicted subsequent memory. In line with the previous result, only for the categorical model, the average recognition performance of each scene exhibited a positive correlation with the average visual dissimilarity between the item in question and its respective lures. These results strongly suggest that even in memory tests that ostensibly rely solely on visual cues (such as forced-choice visual recognition with similar distractors), memory decisions for scenes may be primarily influenced by categorical rather than sensory representations.
Some memories are vivid and detailed, while others are vague and indistinct. Although a common experience, the cognitive mechanisms underlying these differences remain poorly understood. A common explanation for what makes mental representations vivid is their shared properties with visual perception. However, recent research has shown that semantic properties of stimuli strongly influence their representations. To determine the extent to which visual and/or semantic properties influence memory vividness, we first examined whether individual stimuli reliably elicit similar subjective feelings of vividness across different subjects. Next, we explored how vividness relates to visual (i.e., color and brightness) and semantic (i.e., taxonomic category) properties of naturalistic images (Experiment 1). We found that vividness ratings were consistent across subjects; crucially, this consistency depended not only on the visual properties of the stimuli but also on their semantic properties. We then employed Deep Neural Networks to select stimuli based on their visual or semantic features (Experiment 2). Our results showed that stimuli selected for their semantic—but not those selected purely for their visual—properties reliably elicited vivid memories. Finally, we demonstrated that even in a purely visual recall test (Experiment 3), where both encoding and retrieval operations focused exclusively on the visual properties of a mnemonic cue, memory vividness still depended on the integration of visual and semantic stimuli representations. Together, our findings demonstrate, at multiple levels of inference, that although vividness is often compared to perception, this subjective quality of memory is shaped by our knowledge of the world.
Episodic counterfactual thinking (ECT) consists of imagining alternative outcomes to past personal events. Previous research has shown that ECT shares common neural substrates with episodic future thinking (EFT): our ability to imagine possible future events. Both ECT and EFT have been shown to critically depend on the hippocampus, and past research has explored hippocampal engagement as a function of the perceived plausibility of an imagined future event. However, the extent to which the hippocampus is modulated by perceived plausibility during ECT is unknown. In this study, we combine two functional magnetic resonance imaging datasets to investigate whether perceived plausibility modulates hippocampal activity during ECT. Our results indicate that plausibility parametrically modulates hippocampal activity during ECT, and that such modulation is confined to the left anterior portion of the hippocampus. Moreover, our results indicate that this modulation is positive, such that increased activity in the left anterior hippocampus is associated with higher ratings of ECT plausibility. We suggest that neither effort nor difficulty alone can account for these results, and instead suggest possible alternatives to explain the role of the hippocampus during the construction of plausible and implausible ECT.
People often engage in episodic counterfactual thinking, or mentally simulating how the experienced past might have been different from how it was. A commonly held view is that mentally simulating alternative event outcomes aids in managing future uncertainty and improving behavior, for which episodic counterfactual simulations need to be remembered. Yet the phenomenological factors influencing the memorability of counterfactual simulations remain unclear. To investigate this, we conducted two experiments using a paradigm where participants recalled autobiographical memories. After 1 week, they created counterfactual mental simulations of these memories, integrating a new object into each one and rating them on various phenomenological characteristics. Memory for these counterfactual mental simulations was tested the next day by recalling the new object. Across the two experiments we found that objects included in more plausible counterfactual simulations were better remembered compared with implausible counterfactual simulations. Our findings suggest that generating episodic counterfactual simulations perceived as plausible enhances their memorability, similar to other memory phenomena in which schematic knowledge improves subsequent episodic memory.
People often engage in episodic counterfactual thinking, simulating alternative ways in which past events might have unfolded. Existing research has shown that the perceived plausibility of episodic counterfactual simulations influences judgments of regret, mood, prosocial behavior, and false memories. However, knowledge about the factors influencing the perceived plausibility of episodic counterfactuals is limited or derived from studies using hypothetical scenarios. In this study, we test three potential factors that influence the perceived plausibility of episodic counterfactual thoughts: the difficulty of generating the simulation, the vividness of the simulation, and a sampling process that prioritizes plausible alternatives. Experiment 1 (N = 91) showed that while plausibility is related to both difficulty and vividness, it does not depend solely on either factor. Experiment 2 (N = 468) demonstrated that when people generate episodic counterfactual thoughts, they initially produce the most plausible and vivid mental simulations, without concurrent changes in difficulty. These findings suggest that the vividness and difficulty of a mental simulation do not determine the plausibility of episodic counterfactual thinking. Taken together, our results provide support for a sampling process that prioritizes the generation of more plausible and vivid counterfactual alternatives over less difficult ones.
The capacity for goal-directed behavior relies on the generation and implementation of task sets. While task sets are traditionally defined as mnemonic ensembles linking task goals to stimulus–response mappings, we here asked the question whether they may also entail information about task difficulty: does the level of focus required for performing a task become incorporated within the task set? We addressed this question by employing a cued task-switching protocol, wherein participants engaged in two intermixed tasks with trial-unique stimuli. Both tasks were equally challenging during a baseline and a transfer phase, while their difficulty was manipulated during an intermediate learning phase by varying the proportion of trials with congruent versus incongruent response mappings between the two tasks. Comparing congruency effects between the baseline and transfer phases, Experiment 1 showed that the task with a low (high) proportion of congruent trials in the learning phase displayed reduced (increased) cross-task interference effects in the transfer phase, indicating that the level of task focus required in the learning phase had become associated with each task set. Experiment 2 indicated that strengthening of task focus level in the task with a low proportion of congruent trials was the primary driver of this effect. Experiment 3 ruled out the possibility of cue–control associations mediating this effect. Taken together, our results show that task sets can become associated with the focus level required to successfully implement them, thus significantly expanding our concept of the type of information that makes up a task set.
