Other-centred bias in perception and epistemic justification. (under review) PDF
According to traditional phenomenal approaches to perceptual justification, perceptual experience provides rational support for actions, beliefs, and intentions. When you see a banana as yellow, that perceptual experience makes it reasonable for you to believe that the banana is yellow. But decades of research show that other people have an implicit impact on individual perception and cognition: perception is often other-centred or "altercentric". This influence even occurs with the mere presence of others: we unconsciously and spontaneously encode others’ perceptual perspectives and shift our frame of reference accordingly. What is the epistemic standing of altercentic biased perception? This paper introduces and maps the epistemic profile of this phenomenon. I contrast altercentric bias with closely related phenomena, including cognitive penetrability of perception and exogenous attention capture. I argue that under certain conditions it poses unique and novel problems to the epistemic justificatory role of perception.
Explaining joint attention: Between epistemic justification and psychological processing. (under review) OSF Preprint
The ability to engage in joint attention, in which two individuals attend to the same object or event together, is considered fundamental for language learning, for understanding others and for joint actions. Joint attention is often defined as a mutually open, or transparent relation between co-attenders. But how should this openness be characterised? Two broad theoretical views have been proposed. One view reductively accounts for the mutual awareness characteristic of joint attention in terms of individual mental states and properties. According to non-reductive views, in contrast, mutual awareness is based on some primitive intersubjective relation, which is irreducible to the individual states of its relata. I argue that tensions in these approaches arise from the attempt to address both normative and cognitive explananda simultaneously. Both approaches are primarily designed to tackle the normative epistemological concerns of joint attention, and their problems arise when they conflate these concerns with psychological ones. Drawing from evidence in developmental and cognitive psychology, I outline the case for a cognitive-first account of joint attention based on a weaker notion of openness and mutual awareness. I conclude by assessing the epistemic implications of this account.
Peer-reviewed publications
Battich, L., Pacherie, E., & Grèzes, J. (2025) Social perspective-taking influences on metacognition. Cognition, 254, 105966. doi: 10.1016/j.cognition.2024.105966. pdf
We often effortlessly take the perceptual perspective of others: we represent some aspect of the environment that others currently perceive. However, taking someone's perspective can interfere with one's perceptual processing: another person's gaze can spontaneously affect our ability to detect stimuli in a scene. But it is still unclear whether our cognitive evaluation of those judgements is also affected. In this study, we investigated whether social perspective-taking can influence participants' metacognitive judgements about their perceptual responses. Participants performed a contrast detection task with a task-irrelevant avatar oriented either congruently or incongruently to the stimulus location. By "blindfolding" the avatar, we tested the influence of social perspective-taking versus domain-general directional orienting. Participants had higher accuracy and perceptual sensitivity with a congruent avatar regardless of the blindfold, suggesting a directional cueing effect. However, their metacognitive efficiency was modulated only by the congruency of a seeing avatar. These results suggest that perceptual metacognitive ability can be socially enhanced by sharing perception of the same objects with others.
Yavuz, M., Bonicalzi, S., Schmitz, L., Battich, L., Esmaily, J., & Deroy, O. (2025). Rational choices elicit stronger sense of agency in brain and behavior. Cognition, 254, 106062. doi: 10.1016/j.cognition.2025.106062. pdf
The sense of agency is the subjective feeling of control over one's own actions and the associated outcomes. Here, we asked whether and to what extent the reasons behind our choices (operationalized by value differences, expected utility, and counterfactual option sets) drive our sense of agency. We simultaneously tested these three dimensions during a novel value-based decision-making task while recording explicit (self-reported) and implicit (brain signals) measures of agency. Our results show that choices that are more reasonable also come with a stronger sense of agency: humans report higher levels of control over the outcomes of their actions if (1) they were able to choose between different option values compared to randomly picking between options of identical value, (2) their choices maximizes utility (compared to otherwise) and yields higher than expected utility, and (3) they realize that they have not missed out on hidden opportunities. EEG results showed supporting evidence for factors (1) and (3): We found a higher P300 amplitude for picking than choosing and a higher Late-Positive Component when participants realized they had missed out on possible but hidden opportunities. Together, these results suggest that human agency is not only driven by the goal-directedness of our actions but also by their perceived rationality.
Battich, L. & Deroy, O. (2023). Cognitive penetration and implicit cognition. In Thompson, R.J. (Ed.), Routledge Handbook of Philosophy and Implicit Cognition (pp. 144-152). Routledge. pdf
Cognitive states, such as beliefs, desires and intentions, may influence how we perceive people and objects. If this is the case, are those influences worse when they occur implicitly rather than explicitly? Here we show that cognitive penetration in perception generally involves an implicit component. First, the process of influence is implicit, making us unaware that our perception is misrepresenting the world. This lack of awareness is the source of the epistemic threat raised by cognitive penetration. Second, the influencing state can be implicit, though it can also be or become explicit. Being unaware of the content of the influencing state, we argue, does not make as much difference to the epistemic threat as it does to the epistemic responsibility of the agent. Implicit influencers cannot be examined for their accuracy and justification, and cannot be voluntarily accepted by the perceiver. Conscious awareness, however, is not sufficient for attributing blame to the agent. An equally important condition is the degree of control that they can exercise to change the contents that influence perception or stop their influence. Here we suggest that such control can also result from social influence, and that cognitive penetrability of perception is therefore also a social issue.
Battich, L., Garzorz, I., Wahn, B., & Deroy, O. (2021). The impact of joint attention on the sound-induced flash illusions. Attention, Perception, & Psychophysics, 83(8), 3056–3068. doi: 10.3758/s13414-021-02347-5. pdf
Humans coordinate their focus of attention with others, either by gaze following or prior agreement. Though the effects of joint attention on perceptual and cognitive processing tend to be examined in purely visual environments, they should also show in multisensory settings. According to a prevalent hypothesis, joint attention enhances visual information encoding and processing, over and above individual attention. If two individuals jointly attend to the visual components of an audiovisual event, this should affect the weighing of visual information during multisensory integration. We tested this prediction in this preregistered study, using the well-documented sound-induced flash illusions, where the integration of an incongruent number of visual flashes and auditory beeps results in a single flash being seen as two (fission illusion) and two flashes as one (fusion illusion). Participants were asked to count flashes either alone or together, and expected to be less prone to both fission and fusion illusions when they jointly attended to the visual targets. However, illusions were as frequent when people attended to the flashes alone or with someone else, even though they responded faster during joint attention. Our results reveal the limitations of the theory that joint attention enhances visual processing as it does not affect temporal audiovisual integration.
Battich, L. and Geurts, B. (2021). Joint attention and perceptual experience. Synthese, 198(9), 8809-8822. doi: 10.1007/s11229-020-02602-6. pdf
Joint attention customarily refers to the coordinated focus of attention between two or more individuals on a common object or event, where it is mutually "open" to all attenders that they are so engaged. We identify two broad approaches to analyse joint attention, one in terms of cognitive notions like common knowledge and common awareness, and one according to which joint attention is fundamentally a primitive phenomenon of sensory experience. John Campbell's relational theory is a prominent representative of the latter approach, and the main focus of this paper. We argue that Campbell's theory is problematic for a variety of reasons, through which runs a common thread: most of the problems that the theory is faced with arise from the relational view of perception that he endorses, and, more generally, they suggest that perceptual experience is not sufficient for an analysis of joint attention.
Battich, L., Fairhurst, M., & Deroy, O. (2020). Coordinating attention requires coordinated senses. Psychonomic Bulletin & Review, 27(6), 1126–1138. doi: 10.3758/s13423-020-01766-z. pdf
From playing basketball to ordering at a food counter, we frequently and effortlessly coordinate our attention with others towards a common focus: we look at the ball, or point at a piece of cake. This non-verbal coordination of attention plays a fundamental role in our social lives: it ensures that we refer to the same object, develop a shared language, understand each other’s mental states, and coordinate our actions. Models of joint attention generally attribute this accomplishment to gaze coordination. But are visual attentional mechanisms sufficient to achieve joint attention, in all cases? Besides cases where visual information is missing, we show how combining it with other senses can be helpful, and even necessary to certain uses of joint attention. We explain the two ways in which non-visual cues contribute to joint attention: either as enhancers, when they complement gaze and pointing gestures in order to coordinate joint attention on visible objects, or as modality pointers, when joint attention needs to be shifted away from the whole object to one of its properties, say weight or texture. This multisensory approach to joint attention has important implications for social robotics, clinical diagnostics, pedagogy and theoretical debates on the construction of a shared world.
Battich, L. (2018). Are non-human primates Gricean? Intentional communication in language evolution. Pulse: A History, Sociology and Philosophy of Science Journal. Vol. 5, 70-88. pdf, journal page
The field of language evolution has recently made Gricean pragmatics central to its task, particularly within comparative studies between human and non-human primate communication. The standard model of Gricean communication requires a set of complex cognitive abilities, such as belief attribution and understanding nested higher-order mental states. On this model, non-human primate communication is then of a radically different kind to ours. Moreover, the cognitive demands in the standard view are also too high for human infants, who nevertheless do engage in communication. In this paper I critically assess the standard view and contrast it with an alternative, minimal model of Gricean communication recently advanced by Richard Moore. I then raise two objections to the minimal model. The upshot is that this model is conceptually unstable and fails to constitute a suitable alternative as a middle ground between full-fledged human communication and simpler forms of non-human animal communication.