Touching objects to "check" that they are real is a widespread phenomenon — seen both in famous anecdotes, everyday life and eventually in clinical cases of OCD. Tangibility, as the direct contact with objects, seems to give us a straightforward, first-hand sense of what is both present and real. But is that some common sense assumption — that touch is less likely to deceive us — or other factors at play? In this talk, I want to explore how tangibility — our experience of touch — relates to our sense of reality, and what this reveals about the different contributions of perceptual vs. metacognitive aspects on how we perceive objects or the world as real.

Our brain is able to turn external signals coming into our senses into a vivid and coherent experience of reality. At the same time, our brain is also able to generate sensory experience in the absence of external signals via imagination. Contrary to our intuition, our experience of reality is not an objective reflection of the external world, since the brain has no direct access to that. Instead, what we perceive as reality is an inference that the brain makes about its own activity, which is both externally driven (by sensory input) and internally driven (by imagination). Recent research has shown that imagining something leads to similar patterns of activity in sensory cortex as perceiving that same thing in reality. This raises the question; how does our brain determine whether sensory activity represents reality or imagination? In this talk I will discuss our recent attempts to answer this question with empirical research. We developed an experimental paradigm that generates confusions between imagination and perception in healthy volunteers, allowing us to precisely characterize the parameters that lead to these confusions. We then used a combination of psychophysics, computational modelling and neuroimaging to characterize underlying mechanisms. Initial findings suggest that the sense of reality is determined by the strength of sensory signals. This means that if imagination gets strong enough, it feels real. Furthermore, something can feel real (experience) but we might still know it is not real (belief), such as during lucid dreaming. We aim to explain these dissociations by proposing a hierarchical architecture for inferences on reality where lower levels reflect sensory activity and higher levels reflect metacognitive judgements about this activity. I will discuss potential implications of these findings for our understanding of psychiatric disorders of reality monitoring and end by outlining future directions. 

According to traditional phenomenology, perception involves the feeling that its object is real, whereas imagination involves the sense that its object is not real, or unreal. In other words, the formal object of perception is reality, whereas the formal object of imagination is unreality. Nevertheless, there seem to be cases where we feel that what we imagine is real, even if we do not believe that it is. The talk explores some of these cases, in relation to two relevant notions in recent philosophy of imagination, namely "constrained imagination" (Amy Kind) and "actuality-oriented imagination" (Daniel Munro). Examining the sense of reality in imagination can help us elucidate its role in other attitudes, including perception and memory.

Recent work in the philosophy of memory has rekindled a long-standing preoccupation in the history of the subject with the question as to what distinguishes remembering from imagining. In this context, the idea that remembering involves a 'feeling of pastness' (or similar) has also been revived, and has been given an update, in so far as it has been claimed that certain empirical studies have unearthed the psychological underpinnings of the feeling in question. I look at some of the motivations that have been given for the relevant sets of views, the explanatory role the purported 'feeling of pastness' is meant to play in them, and how the empirical findings have been interpreted in this context. I argue that some of the existing work in this area fails to take sufficient account of the difference between two quite different explanatory questions, making the term 'feeling of pastness' a misnomer. 

Suppose you episodically remember the moment at which you looked at the sunset on the first day of your last summer vacation. Prompted to describe this mental state, you’ll probably say that what is represented is conscious as having actually occurred, or that it feels real. Most episodic memories come with a sense of reality, they have an “assertive phenomenology” (Fernandez, 2006). This talk will investigate what the sense in question is. It will do so by discussing some main views about the phenomenology of episodic remembering. I will consider and discuss three candidate accounts. Two of them are one-tiered accounts, one accounting for the assertive phenomenology in terms of the propositional content of a memory (Fernández, 2019), the other in terms of a particular type of experiential knowledge retained by a memory (Hoerl, 2022). The third one is a two-tiered account in terms of epistemic feelings associated to a memory (Dokic, 2014, 2021; Perrin et al., 2020). I will argue that the latter should be preferred. To do so, I will draw on empirical studies of two symmetrical cases. On the one hand, non-believed memories, that is episodic memories from which belief has been withdrawn, but which “continue to feel … as if [the event apparently remembered] had occurred” (Mazzoni et al., 2010, my emphasis); on the other hand, derealized memories, that is episodic memories that come with a “sense of unreality” of what is remembered (Sierra, 2009), however believed they are otherwise.