> [!NOTE] > [[the structure]] here is all over the place # [[Psychedelic Aesthetics]]: A [[Predictive Processing]] Approach ## 1. [[Introduction This]] paper explores [[the relationship between]] [[aesthetic experience]] and [[psychedelic experience]]. Intuitions might pull either way here. On the one hand, people who have taken psychedelics will very often speak about their experiences in aesthetic terms. On the other, one might place LSD, magic mushrooms, and similar substances in the 'mindless hedonism' category: tripping is not, in and of itself, aesthetic, in the same way that getting drunk is not, in and of itself, aesthetic. A skeptic might try to make their complaints more acute by asking us to consider two connected questions. First, what are [[the objects]] of an aesthetic [[psychedelic experience]]? We typically think of the targets of [[aesthetic appreciation]] as shareable (you and I can both appreciate the same painting or landscape, for example). But psychedelic experiences vary considerably across individuals and occurrences. Neither does it seem plausible to say that [[the objects]] of appreciation are the psychedelic substances themselves: the perceivable properties of a tab of acid (size, shape, taste) are not that much different from a postage stamp. This leads directly to the second difficult question: how do we appreciate whatever it is we are appreciating? Traditional models of [[aesthetic appreciation]] focus on [[perceptual attention]] to publicly accessible objects or events. But psychedelic experiences involve profound alterations to the very mechanisms of perception and attention. In this paper, I argue that we can make sense of psychedelic [[aesthetic experience]] by drawing on three [[theoretical frameworks]]: predictive processing accounts of perception, Hohwy's model of introspection, and Nanay's account of aesthetic appreciation. Together, these provide the resources to answer both questions posed above. I propose that the objects of psychedelic aesthetic experience are novel relationships between altered perceptual processing and altered perceptual content—what I will call "psychedelic experience-content properties." These properties become available for appreciation through unique forms of distributed attention made possible by psychedelic-induced changes to predictive processing. This approach not only clarifies how psychedelic experiences can be genuinely aesthetic but also offers insights into aesthetic experience more broadly. ## 2. Predictive Processing and Perception ### 2.1 The Basics of Predictive Processing To understand psychedelic aesthetics, we first need a framework for understanding perception itself. The predictive processing framework offers a powerful and increasingly well-supported model of how our brains make sense of sensory input. According to this framework, perception is not a passive, bottom-up process of building representations from incoming sensory data. Instead, perception involves the brain actively generating predictions about what it expects to encounter, then comparing these predictions with actual sensory input. Any mismatch between prediction and input generates "prediction error," which the brain tries to minimize. This prediction error minimization happens across multiple levels of a hierarchical system. Higher levels in the cortex generate predictions that cascade down to lower levels, while prediction errors travel back up the hierarchy to update the brain's internal models. Over time, this process allows the brain to construct increasingly accurate models of the causal structure of the world. Crucially, this system doesn't just passively adjust predictions to match input. It can also minimize prediction error by acting on the world to make sensory input match predictions (known as "active inference"), or by adjusting the relative weight given to predictions versus sensory input through "precision-weighting." Precision-weighting determines how much influence a given prediction error has on updating our models. High-precision prediction errors drive substantial updates to our models, while low-precision errors are effectively ignored. This mechanism serves as the brain's way of handling uncertainty—giving more weight to reliable information and less to unreliable information. This precision-weighting mechanism proves crucial for understanding both attention and aesthetic experience. When we attend to something, we're effectively increasing the precision of prediction errors associated with that thing, allowing those errors to have greater influence on our perceptual models. ### 2.2 The Relationship Between Predictive Processing and Aesthetic Experience The predictive processing framework offers natural resources for understanding aesthetic experience. In ordinary perception, prediction errors serve primarily as learning signals—prompting updates to our models to better predict future input. But in aesthetic contexts, prediction errors can take on a different character. Art often creates what we might call "controlled prediction errors"—mismatches between expectation and sensory input that aren't immediately resolved. Think of the deliberately ambiguous perspectives in cubist paintings, the unexpected harmonies in jazz, or the subverted narrative expectations in experimental film. These don't simply update our models and disappear; instead, they create a productive tension that sustains aesthetic engagement. What distinguishes aesthetic prediction errors from ordinary ones? Several factors seem important: 1. They occur within a controlled context where immediate action isn't required 2. They remain partially unresolved, creating productive tension 3. They reveal something about the nature of our perceptual processes themselves 4. They involve precision-weighting across multiple levels of processing simultaneously This last point deserves elaboration. Aesthetic experience often involves a unique distribution of attention—what Nanay (2016) calls "distributed attention"—where we attend simultaneously to multiple aspects or levels of a phenomenon. In predictive processing terms, this means precision-weighting that enhances prediction errors at multiple levels of the predictive hierarchy. With this basic framework in place, we can now turn to how predictive processing helps us understand introspection—a crucial step toward understanding psychedelic aesthetic experience. ## 3. Introspection as Prediction Error Minimization ### 3.1 Hohwy's Model of Introspection Introspection—our ability to attend to our own experiences—presents an interesting challenge for predictive processing accounts. How can the brain, which is normally busy predicting the external world, turn its predictive machinery on itself? Jakob Hohwy (2013) offers an elegant solution, suggesting that introspection employs the same prediction error minimization mechanisms used in external perception, but directed at experiences themselves. In ordinary perception, the brain minimizes prediction error between its models and sensory input from the world. In introspection, it minimizes prediction error between higher-level models of experience and the experiences themselves. But when would we need to introspect? Hohwy suggests we engage in introspection when we encounter "violations of experiential expectation"—when our experiences themselves don't match what we expect them to be like. For example: - When pain is unexpectedly sharp despite a light impact - When scratching an itch produces pain rather than relief - When colors suddenly appear unusually bright - When expected perceptual effects don't materialize In these cases, simple adjustments to our models of the world don't resolve the prediction error. Instead, we must consider whether something unusual is happening with our perceptual processes themselves. This triggers introspection—prediction error minimization directed at experience. Hohwy points out an interesting feature of introspection he calls "introspective dissonance." When we introspect, our experiences seem both easily accessible and certain (I know I'm in pain) yet also elusive and uncertain (I struggle to precisely characterize exactly what this pain is like). This dissonance emerges naturally from the hierarchical structure of predictive processing. ### 3.2 The Hierarchical Structure of Experience To understand introspective dissonance, we need to recognize that experiences themselves are represented across multiple levels of the predictive hierarchy: - Higher levels represent general categories and integrated features of experience (e.g., "I'm experiencing blue") - Lower levels represent more specific, detailed aspects of experience (e.g., the exact shade, texture, and spatial distribution of blueness) The certainty in introspection comes from accessing high-level representations, which are relatively stable and integrated. These high-level representations are "winners" in the predictive competition—hypotheses with the highest posterior probability. They engage higher levels of the perceptual hierarchy marked by invariance and perspective-independence, making them relatively easy to access. The uncertainty comes when we try to access lower-level aspects of experience, which contain more noise, variability, and fine-grained detail. As Hohwy puts it, introspective attention is "doomed to failure because the very existence of high-level representations that are not bound to concurrent sensory evidence depends upon a suppression of precision at sensory levels." This hierarchical structure explains both the certainty and uncertainty of introspection. It also reveals something important: introspection itself involves navigating relationships between different levels of experiential representation. ### 3.3 Experience-Content Properties These relationships between different levels of experiential representation constitute what I'll call "experience-content properties." These are relational properties that cannot be fully characterized without reference to both: 1. The qualities of the experience itself (how it feels, its phenomenal character) 2. What the experience represents (what it's about, its intentional content) For example, when you experience pain, there's a relationship between the sharp, burning quality of the pain experience and what this tells you about the damage to your body. Or when you see vibrant colors, there's a relationship between the intensity of your color experience and the surface reflectance properties it represents. These experience-content properties emerge from cross-level predictions in the predictive hierarchy—predictions that link experiential qualities to what they represent. When we introspect effectively, we're attending to these relationships. This concept of experience-content properties provides a crucial link between introspection and aesthetic appreciation, particularly as understood through Nanay's account of picture perception. ## 4. Nanay's Model of Picture Perception and Aesthetic Experience ### 4.1 Picture Perception as Multi-level Representation Bence Nanay's work on picture perception offers valuable insights for understanding aesthetic experience. Nanay observes that when we look at pictures, we perceive both the two-dimensional surface (with its marks, colors, and textures) and the three-dimensional scene depicted. This creates a unique perceptual state where we represent both aspects simultaneously. Nanay argues that we don't alternate between seeing the surface and seeing the depicted scene (as Gombrich suggested), nor do we simply imagine seeing the depicted scene while actually perceiving only the surface (as Walton proposed). Rather, we genuinely perceive both, though we typically attend only to the depicted scene. In predictive processing terms, picture perception involves predictions at multiple levels of the hierarchy: - Predictions about the physical properties of the picture surface - Predictions about the depicted three-dimensional scene - Crucially, predictions about how specific surface features create specific depicted content When we look at pictures, our visual system maintains these different sets of predictions simultaneously, though we normally focus our attention (precision-weighting) on the depicted content rather than the surface. ### 4.2 Design-Scene Properties The key insight from Nanay's account for our purposes involves what he calls "design-scene properties." These are relational properties that cannot be fully characterized without reference to both the picture's surface and the depicted scene. Nanay defines design-scene properties as "relational properties that cannot be fully characterized without reference to both the picture's surface and to the three-dimensional object visually encoded in the surface." For example, when looking at a Miró drawing where two simple curved lines somehow depict an expressive human face, we can appreciate the relationship between those specific lines (surface properties) and the specific facial features they depict (scene properties). Similarly, when appreciating Cézanne's landscapes, we might notice the relationship between individual brushstrokes and the pine needles they depict. Within the predictive processing framework, design-scene properties emerge from cross-level predictions that link specific surface features to specific depicted content. These cross-level predictions represent how particular marks on the surface give rise to particular aspects of the depicted scene. ### 4.3 Aesthetic Appreciation as Distributed Attention Nanay argues that aesthetic appreciation of pictures involves a special form of attention he calls "distributed attention." When appreciating pictures aesthetically, our attention is "focused with regards to objects but distributed with regards to properties." We focus on the picture as a single object but distribute our attention across both its surface properties and the properties of the depicted scene. This distributed attention enables us to appreciate design-scene properties—the relationships between surface features and depicted content. In predictive processing terms, aesthetic appreciation involves precision-weighting that enhances prediction errors at multiple levels of the hierarchy simultaneously, making us sensitive to both surface and depicted content. The parallels with introspection are striking. Just as introspection involves attending to relationships between different levels of experiential representation (experience-content properties), aesthetic appreciation of pictures involves attending to relationships between different levels of pictorial representation (design-scene properties). Both require a form of distributed attention that spans multiple levels of the predictive hierarchy. This conceptual connection between introspection and aesthetic appreciation provides the foundation for understanding psychedelic aesthetics. ## 5. Psychedelic Experience Through the Predictive Processing Lens ### 5.1 How Psychedelics Alter Predictive Processing Recent neuroscientific research suggests that psychedelics like LSD and psilocybin work by temporarily disrupting normal predictive processing. The REBUS model (RElaxed Beliefs Under pSychedelics) proposed by Carhart-Harris and Friston (2019) argues that psychedelics decrease the precision of high-level priors while increasing the precision of bottom-up prediction errors. In normal perception, high-level priors constrain the interpretation of incoming sensory data, allowing only those interpretations that fit with our existing models. This ensures perceptual stability but can also lead to rigidity. Psychedelics appear to relax these constraints by reducing the influence of high-level priors, allowing bottom-up information to have greater influence on perception. The neuropharmacological mechanism involves serotonin 2A receptor activation, which disrupts the functioning of cortical pyramidal neurons that normally encode high-level priors. This disruption leads to several characteristic effects: 1. Increased entropy in neural activity (more random, less constrained) 2. Enhanced bottom-up information flow 3. Decreased top-down constraint 4. Altered precision-weighting across the predictive hierarchy These neural changes manifest as the classic psychedelic experiences: visual distortions, synesthesia, ego dissolution, and altered conceptual thinking. But they also create unique conditions for aesthetic experience. ### 5.2 The Objects of Psychedelic Aesthetic Experience We can now address our first question: what are the objects of psychedelic aesthetic experience? I propose that psychedelic experiences make available novel experience-content properties—relationships between altered perceptual processing and altered perceptual content that aren't accessible in ordinary states of consciousness. These novel relationships become the objects of aesthetic appreciation. Consider visual distortions. When walls appear to "breathe" under psychedelics, this isn't simply a hallucination. Rather, it reflects an altered relationship between visual processing and visual content. Specifically, the brain's normal predictions about the stability of surfaces are relaxed, allowing bottom-up information about subtle changes in light, shadow, and texture to have greater influence on perception. What makes this aesthetic rather than merely unusual is that these novel experience-content properties reveal something important about the nature of perception itself. They make visible the usually invisible constructive processes that underlie ordinary perception. Other examples include: - Enhanced pattern recognition, where meaningful patterns emerge from normally unremarkable textures - Synesthesia, where cross-modal relationships between sensory modalities become directly perceivable - Altered self-experience, where the predictive processes that constitute the sense of self become accessible to awareness These novel experience-content properties are the objects of psychedelic aesthetic experience—the "what" that is being appreciated. ### 5.3 Mechanisms of Psychedelic Aesthetic Appreciation This brings us to our second question: how do we appreciate these novel experience-content properties? The mechanism is a uniquely altered form of distributed attention. Psychedelics create conditions where attention can be distributed across levels of processing that are normally inaccessible to awareness. By disrupting the normal hierarchical organization of predictive processing, psychedelics allow us to attend simultaneously to multiple levels of perceptual construction. This altered distribution of attention enables appreciation of the relationships between normally unconscious perceptual processes and their conscious contents. It's analogous to how aesthetic appreciation of pictures involves distributed attention to both surface and depicted content, but psychedelics extend this distribution to include normally unconscious aspects of perceptual processing. The result is a meta-perceptual awareness—an awareness not just of what we perceive but of how we perceive. This meta-perceptual awareness is central to psychedelic aesthetic experience. It allows us to appreciate the constructive nature of perception in a direct, experiential way that isn't possible in ordinary states of consciousness. ## 6. Analyzing Specific Psychedelic Phenomena as Aesthetic ### 6.1 Visual Distortions and Pattern Recognition Visual distortions are among the most common psychedelic effects. Surfaces may appear to breathe or flow, colors may intensify, and patterns may emerge from normally homogeneous textures. These effects can be understood as altered experience-content properties. Consider the common experience of seeing meaningful patterns in textures like wood grain, clouds, or carpets—a phenomenon known as pareidolia. In ordinary perception, our visual system suppresses most instances of pareidolia through strong top-down constraints. We might occasionally see a face in a cloud, but these perceptions are fleeting and easily dismissed. Under psychedelics, these constraints are relaxed, allowing pattern-recognition mechanisms to operate more freely. The experience reveals the normally hidden constructive processes of perception—how our visual system actively organizes sensory input into meaningful patterns rather than passively registering pre-existing patterns in the world. What makes this aesthetic is the distributed attention it enables—attention not just to the patterns themselves but to the relationship between perceptual processes and perceptual content. We become aware of how our perceptual processes actively construct the patterns we see, creating an appreciation of the creative aspects of ordinary perception. ### 6.2 Synesthesia and Cross-modal Binding Synesthesia—the blending of sensory modalities where sounds might be seen or colors might be heard—offers another example of psychedelic aesthetic experience. In ordinary perception, our sensory modalities are integrated but distinct. Under psychedelics, the boundaries between modalities become more permeable, revealing cross-modal relationships that normally remain implicit. Music might trigger visual imagery that seems perfectly matched to the sonic qualities, or textures might evoke tastes. These experiences reveal the cross-modal predictions that underlie ordinary perception—how our brains integrate information across sensory modalities to construct a unified experience. By making these cross-modal relationships more explicit, psychedelics allow them to become objects of aesthetic appreciation. The aesthetic quality comes from distributed attention to both the individual sensory contents and the relationships between them. We appreciate not just the sound or the imagery but the specific way they relate to each other—the "design-scene properties" of cross-modal experience. ### 6.3 Altered Self-Experience Perhaps the most profound aesthetic dimension of psychedelic experience involves alterations to the sense of self. These range from subtle changes in body image to complete "ego dissolution" where the boundary between self and world temporarily disappears. From a predictive processing perspective, the sense of self emerges from hierarchical predictions about the boundary between organism and environment. These predictions normally operate automatically and unconsciously, maintaining a stable sense of self across changing contexts. Psychedelics disrupt these predictions, making the constructive nature of selfhood directly accessible to awareness. This can reveal how the sense of self is not a fixed entity but an ongoing process of prediction and error minimization. The aesthetic dimension comes from distributed attention to both the content of self-experience and the processes that construct it. We appreciate the relationship between specific aspects of selfhood and the predictive processes that give rise to them—the "design-scene properties" of self-experience. This can connect to profound aesthetic traditions across cultures, from Buddhist contemplative practices to romantic notions of the sublime, where altered self-experience serves as a gateway to aesthetic insight. ## 7. Addressing Philosophical Objections ### 7.1 The Problem of Shareability A significant objection to understanding psychedelic experiences as aesthetic concerns shareability. Traditional aesthetic objects like paintings or symphonies can be experienced by multiple people, while psychedelic experiences seem private and variable. The predictive processing account offers a response: what's shared in psychedelic aesthetic experience is not specific content but structural features of altered predictive processing. Different individuals may experience different contents, but the underlying alterations to predictive mechanisms show consistent patterns across individuals. This is analogous to how different viewers might notice different specific design-scene properties in a painting while all engaging in the same general form of distributed attention. The shareability lies in the structure of the aesthetic engagement rather than in identical content. Moreover, phenomenological reports from psychedelic experiences show remarkable similarities across individuals and cultures, suggesting greater shareability than might initially appear. These similarities reflect common alterations to predictive processing mechanisms that all humans share. ### 7.2 The Problem of Evaluation Another objection concerns evaluation: if psychedelic experiences can be aesthetic, can they be evaluated as better or worse, more or less successful? Traditional aesthetic evaluation applies criteria like coherence, complexity, expressiveness, and insight. These criteria can be adapted to psychedelic aesthetic experiences by focusing on the quality of the relationship between altered processing and altered content. A "successful" psychedelic aesthetic experience might involve: - Rich and complex experience-content properties - Coherent relationships between different levels of processing - Novel insights into the nature of perception or consciousness - Integration of the experience into broader understanding Unsuccessful experiences might involve overwhelming confusion, inability to maintain distributed attention, or failure to form meaningful relationships between processing and content. This approach allows for aesthetic evaluation without reducing the value of psychedelic experiences to purely therapeutic or hedonistic terms. ## 8. Conclusion: Toward a Predictive Processing Aesthetics This paper has offered a new framework for understanding psychedelic experiences as aesthetic by drawing on predictive processing, introspection, and theories of aesthetic attention. I've argued that psychedelic aesthetic experiences involve the appreciation of novel experience-content properties through uniquely distributed forms of attention. These experience-content properties—relationships between altered perceptual processing and altered perceptual content—become accessible through psychedelic-induced changes to predictive processing. This approach addresses both questions posed at the outset: the objects of psychedelic aesthetic experience are novel experience-content properties, and we appreciate them through distributed attention across multiple levels of perceptual processing. Beyond clarifying psychedelic aesthetics, this framework offers broader insights for aesthetic theory. It suggests that aesthetic experience generally involves a meta-perceptual dimension—awareness not just of what we perceive but of how we perceive. This dimension is especially pronounced in psychedelic states but present to some degree in all aesthetic experience. Future research might explore how this framework applies to other altered states like meditation, dreaming, or aesthetic absorption. It might also investigate the neural mechanisms of distributed attention in aesthetic contexts and develop more refined criteria for evaluating psychedelic aesthetic experiences. By bringing psychedelic experiences into aesthetic discourse, we gain new perspectives on both. Psychedelic experiences are not merely strange sensations or mystical insights but can involve sophisticated forms of aesthetic appreciation. And aesthetic theory is enriched by considering how altered states reveal dimensions of experience that remain implicit in ordinary perception. The predictive processing framework provides the conceptual resources for this integration, offering a unified account of perception, introspection, aesthetic appreciation, and psychedelic experience. This synthetic approach not only addresses philosophical questions about psychedelic aesthetics but opens new avenues for understanding the nature of aesthetic experience itself. ## References - Carhart-Harris, R. L., & Friston, K. J. (2019). REBUS and the anarchic brain: Toward a unified model of the brain action of psychedelics. Pharmacological Reviews, 71(3), 316-344. - Hohwy, J. (2013). The predictive mind. Oxford University Press. - Nanay, B. (2016). Aesthetics as philosophy of perception. Oxford University Press. - Nanay, B. (2011). Pictures, phenomenology and cognitive neuroscience. The British Journal of Aesthetics, 51(2), 151-167. - Clark, A. (2016). Surfing uncertainty: Prediction, action, and the embodied mind. Oxford University Press. - Letheby, C. (2021). Philosophy of psychedelics. Oxford University Press. - Noë, A. (2015). Strange tools: Art and human nature. Hill and Wang.