A Handle on Consciousness: Telepresence within the Brain By George Goutos (goutos@comcast.net) Abstract This paper uses the metaphor of a telepresence setup, where an individual on Earth controls a humanoid robot on Mars, to conceptually explore the concept of dissociating consciousness within the brain. This scenario challenges traditional views by suggesting that just as conscious experience can be mediated and extended through technology, the physical localization of consciousness in the brain is also mediated. The potential roles of the cerebellum and brainstem in maintaining a first-person perspective, integrating sensory experiences, and contributing to a unified sense of self and conscious awareness are discussed. The paper engages with existing theories to highlight the need to account for the cerebellum's contributions and concludes with suggestions for future empirical and theoretical research, along with a discussion of the broader philosophical implications. PART 2 TELEPRESENCE WITHIN THE BRAIN Introduction The traditional view of consciousness locates it firmly within the cerebral cortex, emphasizing the role of cortical networks in integrating sensory and motor information to produce a unified conscious experience. This paper challenges this cerebral-centric view by conceptually suggesting that the first-person perspective, a key component of consciousness, may be localized in subcortical regions such as the cerebellum and brainstem. Telepresence Analogy Imagine a scenario where a person's consciousness seems to be separate from their physical location, illustrated through a telepresence setup. Picture an individual on Earth controlling a humanoid robot on Mars. This robot, designed to mimic human appearance and behavior, acts as a bridge between the two worlds. Through a two-way communication link, the robot's onboard processor sends high-resolution sensory data back to the human operator, who then sends motor commands to the robot. This setup allows the operator to remotely control the humanoid, experiencing the Martian environment as if they were physically present. The humanoid robot functions as an extension of the operator's senses, transmitting visual, auditory, tactile, and other information. By controlling the robot's movements and actions, the operator can interact with the Martian environment in real-time, enhancing the feeling of presence. This immersive experience makes it seem as though the operator's consciousness is "located" on Mars. A New Locale Imagine this operator and a humanoid robot having been connected through a telepresence setup since childhood, with Mars as the only environment they know. The operator interacts exclusively with the world via the humanoid, creating a deeply integrated system between human and machine. While this is a theoretical scenario, experiments in virtual and augmented reality show that people can easily adapt to new environments, suggesting that their consciousness, or 'first-person perspective,' becomes aligned with the new landscape as they explore it while their true first-person perspective remains physically anchored. This human-robot interaction (Figure 1) challenges traditional views on consciousness, prompting us to reconsider where our first-person perspective truly resides. If asked, the humanoid will affirm it has a first-person perspective, attributing this to its onboard processor, or 'brain.' As external observers, we recognize that the humanoid is mistaken about the source of its consciousness, which is in fact generated remotely by the operator. Figure 1 Operator on Earth linked wirelessly to Humanoid on Mars. Argument: The Origin of First-Person Perspective Premise 1: The humanoid asserts it possesses a first-person perspective. This premise is based on the humanoid's responses, which suggest it has a first-person perspective of its environment and of its ‘self’. Premise 2: The humanoid believes its first-person perspective originates in its head. This belief is a natural consequence of the humanoid's sensory and cognitive integration. It assumes that the source of consciousness is the same as the physical location of sensory processing, its onboard processor or ‘brain’. Premise 3: The source of the humanoid's perspective is external to its head and body. In the scenario, the humanoid’s sensory inputs and motor outputs are mediated by a remote operator. The operator is the actual source of the humanoid's first-person perspective, challenging the assumption that consciousness must reside where sensory and motor processes occur. Premise 4: The humanoid's perspective is a projection of the operator's perspective. This premise suggests that the humanoid's conscious experience is not intrinsic to the humanoid itself but is a projection of the operator’s consciousness. The humanoid acts as an interface for the operator’s experiences. Conclusion: The humanoid is mistaken in its belief that its first-person perspective originates in its head, its onboard processor. The humanoid’s responses to the location of its own consciousness are fundamentally flawed, as its experiences are generated and controlled remotely. Inference: This raises the possibility that our own first-person perspective might also originate in a location other than where it's thought to be localized. It might originate from somewhere external to our brain or it might originate within our brain but not where our sensory processes occur. The Law of Projection The law of projection, introduced by Smythies in 1954, explains that when a sensory pathway is stimulated centrally, like in the somatosensory cortex of the parietal lobe, the sensation is perceived as coming from the periphery rather than the point of stimulation. This principle helps explain phenomena such as phantom limb sensations, where individuals feel sensations in a limb that is no longer there. Similarly, in a telepresence setup, when a humanoid's finger is touched, the operator experiences the sensation as if it occurred at the robot's artificial nerve ending. This setup challenges the traditional view that consciousness is strictly tied to the brain's physical location, suggesting that consciousness can be experienced as being in a different, distant environment. Anatomical and Functional Characteristics of the Brain The brain consists of the forebrain, the midbrain, and the hindbrain. This paper is concerned primarily with the cerebrum, part of the forebrain, and the cerebellum/brainstem, parts of the hindbrain (Figure 2). The cerebrum includes the two cerebral hemispheres. Figure 2 Cerebellum, Brainstem (with Pons), and Cerebrum Role of the Cerebellum The cerebellum's intricate structure, characterized by uniform folia, allows efficient processing of sensory inputs and motor outputs. Sensory information is received via the cortico-ponto-cerebellar pathways, integrated, and then motor commands are sent back to the cerebral cortex through the cerebello-thalamic and thalamo-cortical pathways (Figure 3). The cortico-ponto-cerebellar pathways are among the most densely packed and highly integrated neural pathways in the brain, reflecting their critical role in linking the cerebral cortex with the cerebellum. The pons acts as a bridge between the cerebellum and cerebrum. Functionally, the cerebellum acts as a predictive model, adjusting motor commands to match sensory feedback, crucial for smooth movements and establishing a stable sense of self. Studies on cerebellar-like structures in sharks and other vertebrates highlight the cerebellum's evolutionary role in complex behaviors. These models of cerebellar function across species contribute to understanding the cerebellum's importance in self-perception. Figure 3 Exploded View of Cerebellum and Cerebrum Role of the Brainstem The cerebellum and brainstem deserve significant attention in understanding consciousness. The brainstem, the most ancient brain part, is crucial for basic physiological functions and the first to develop during embryogenesis. It integrates and coordinates essential survival functions, continuously adapting through complex firing patterns and plasticity. Neurons in the brainstem and cerebellum engage in complex firing patterns modulated by various factors, reflecting the brain's adaptability. The brainstem connects to the deep cerebellar nuclei via pathways like the Guillain-Mollaret-Fuchs (GMF) triangle, refining their functions from embryogenesis through childhood. General anesthetics induce unconsciousness by affecting brainstem networks that regulate wakefulness. Recent research suggests that the cerebellum has significant roles in cognitive functions, emotional regulation, and possibly consciousness (Ito, 2008). Its predictive modeling and integrative capabilities provide a stable reference point for the sense of self, playing a potentially underappreciated role in maintaining conscious experience. Models of Consciousness Centralized models argue that consciousness arises from complex neural processes within the brain, particularly the cerebral cortex, which integrates sensory, motor, and cognitive information. While this model explains many aspects of consciousness, the telepresence analogy questions the necessity of localized neural activity. It suggests that consciousness might not be as straightforwardly localized as commonly thought. The Implicit Self The cerebellum shapes our spatial and temporal sense of self, anchoring us within the brain's continuum. John Montgomery and David Bodznick highlight Masao Ito's view of the cerebellum as the 'brain for the implicit self,' suggesting a ‘self’ adept at differentiating itself from 'other' in interactions with the physical world (Montgomery, Bodznick, 2016). Researchers refer to this as a 'predictive model,' anticipating outcomes based on sensory inputs and motor commands. This predictive capability, refined through reflex motor learning and classical conditioning, contributes to the 'cerebellar self,' a stable construct ensuring precise neural signal coordination. Unlike more dynamic brain structures, the cerebellar self serves as a consistent anchor for self-perception. The Brain and Telepresence: An Analogy The cerebrum and hindbrain both fit within our skull, making it difficult to pinpoint where our first-person perspective originates and where it manifests. The cerebrum processes sensory information and outputs motor commands, which has led researchers to primarily focus on it for both originating and manifesting consciousness. But the hindbrain also processes sensory information and motor commands. Our telepresence analogy suggests we should also consider the hindbrain. Split Origin More interestingly, there’s a third possibility: that the origination and manifestation of our first-person perspective is split within the brain. Mapping the telepresence setup onto the brain, the cerebrum could function as the 'humanoid,' while the hindbrain serves as the operator. In the telepresence model, the cerebrum, like the humanoid, handles sensory organs and motor capabilities, while the hindbrain, like the operator, controls processes from behind the scenes (Figure 4). This analogy suggests that while consciousness appears to manifest in the cerebrum, the hindbrain might play a more significant role, subtly generating the overall experience, orchestrating it quietly in the background. Figure 4 Telepresence Analogy: Operator is to Humanoid as Hindbrain (Cerebellum) is to Cerebrum The first-person perspective The first-person perspective has been referenced multiple times in this paper without in-depth examination. In Part 1 (Goutos, 2024), it was proposed that there might be a unique first-person property responsible for our unique first-person perspectives, accessed by the brain from an external source. This concept, that a first-person perspective might arise from outside the brain, will be explored in Part 3. Suffice it to say here that while this seems to challenge traditional physicalist or materialist views, it can align with these views by positing that such a source, a ‘field’ perhaps, conforms to the laws of physics – be they known or yet-unknown. Reconsidering the Hindbrain's Role in Consciousness The debate over the cerebellum's role in consciousness often centers on its traditional view as primarily a motor coordination hub. This perspective excludes the cerebellum from discussions of consciousness, as it does not show independent signs of conscious experience as does the cerebral cortex. Cerebellar Agenesis For example, individuals with cerebellar agenesis, a condition where the cerebellum is absent, are often reported to lead "normal," and therefore, sentient lives. However, this conclusion may be too simplistic. While the cerebellum's role in motor coordination is well-established, the assumption that cerebellar agenesis does not affect consciousness is debated (Masi, 2003). Criticism and Insights Glickstein (1994) refuted the idea that individuals with complete cerebellar agenesis can be symptom-free, noting significant motor deficits in detailed clinical descriptions. These findings indicate that the absence of the cerebellum does have noticeable effects, raising questions about its broader contributions to brain function, including potential roles in consciousness. The conclusion that individuals with cerebellar agenesis exhibit conscious awareness is supported by their ability to perform cognitive tasks, engage in meaningful communication, and respond to their environment in ways that demonstrate self-awareness and understanding. Clinical observations and neuropsychological assessments reveal that these individuals can recognize themselves, understand and produce language, follow complex instructions, and interact socially, indicating the presence of conscious thought and awareness (Lemon, Edgley 2010). However, it is arguable that these tasks could be carried out by a philosophical zombie, a being that behaves like a normal human but lacks conscious experience. Currently, no definitive test for consciousness exists. There are various tests that assess levels of alertness and wakefulness, but these primarily measure behavioral and physiological responses rather than the presence of a first-person perspective. Split-Brain Research Split-brain research provides unique insights into consciousness, especially concerning hemispheric specialization and communication. In cases where patients have undergone a callosotomy, severing the corpus callosum, studies generally show that these individuals maintain a unified sense of consciousness despite the disconnection between their cerebral hemispheres. The persistence of a unified sense of self and coherent behavior in split-brain patients suggests that inter-hemispheric communication may not be as crucial to consciousness as previously thought. This observation leads to speculation about other brain regions' roles in maintaining unified consciousness, with the cerebellum emerging as a potential candidate. The cerebellum's extensive connectivity with both cerebral hemispheres and its role in coordinating sensory and motor information position it as a possible integrative center supporting a unified conscious experience. Studies, including the influential "Split brain: divided perception but undivided consciousness" by Pinto et al. (2017), have not extensively, if at all, explored the cerebellum's role in this context. Cerebellar Organizational Structure The cerebellum is traditionally viewed as a structure primarily involved in motor coordination, overshadowed by the cerebrum's more dynamic capabilities. Critics often cite the cerebellum’s seemingly rigid and mechanical organization as evidence that it is too isolated from the cerebrum’s interconnected neural network to play a significant role in consciousness. Integrated Information Theory (IIT) This critique aligns with Integrated Information Theory (IIT), which suggests that consciousness arises from the complex integration of information across a network of neurons. Tononi (2008) argues that the cerebellum’s modular and segregated design may inhibit the high levels of integration necessary for consciousness. He likens the cerebellum to a meticulously organized library—efficient in processing and sorting information but lacking the interconnectedness required for a deeper conscious experience. Holistic View However, this interpretation does not fully account for the cerebellum's extensive neural connections and potential contributions to consciousness. The role of the hindbrain in establishing the ‘self’ and possibly the first-person perspective might be analogous to 'common ground' in an electronic circuit, serving as a stable reference point while other components operate at various voltage potentials. Just as each key on an electric keyboard is associated with a unique voltage potential, relative to ground, and produces a unique tone, sensory signals in the brain - representing qualia - might be processed in relation to a comparable 'ground-zero'-like reference point in the cerebellum. This grounding could be crucial for interpreting sensory inputs, suggesting that the cerebellum, with its connections to the brainstem, to the stable ‘self’, and to other regions, may provide a foundational reference point for our perceptual experiences. It may explain why, as far as is known, stimulating bits of the cerebellum doesn’t impact directly on qualia. The stimulation must arrive from without. When the somatosensory cortex of the parietal lobe is stimulated, a first-person perspective of a touch is generated and felt. Perhaps it originated in the cerebellum but was felt in the cerebrum. “This developing view of the cerebellum helps to explain the relatively low profile of the cerebellum in our collective consciousness. ‘It works so well that it can largely be ignored.’” (Montgomery, Bodznick 2016). Literature Review: The Cerebellum and Consciousness The traditional focus on the cerebral cortex in consciousness studies has led to the relative neglect of the cerebellum. However, emerging research indicates that the cerebellum may play a more complex role than previously understood. For instance, Schmahmann and Sherman (1998) identified the cerebellar cognitive affective syndrome, which includes impairments in executive function, spatial cognition, linguistic processing, and affect regulation, suggesting that the cerebellum's functions extend beyond motor control to influence cognitive and emotional processes integral to conscious experience. Predictive Processing Framework Recent theories in neuroscience and philosophy, such as the Predictive Processing framework, propose that the brain constructs a model of the world to predict sensory inputs and minimize prediction error. The cerebellum's role in fine-tuning predictions based on sensory feedback could be crucial in this context, contributing to the brain's ability to generate coherent and unified conscious experiences. Integrated Information Theory (IIT) Integrated Information Theory (IIT) posits that consciousness corresponds to the capacity of a system to integrate information, quantified as phi (Φ). The cerebellum's low Φ is thought to indicate a lesser role in conscious experience. However, this view may underestimate the cerebellum's potential contributions to the global neural dynamics essential for consciousness. Global Workspace Theory (GWT) In contrast, Global Workspace Theory (GWT), which emphasizes the broadcasting of information across a neural workspace, might suggest a limited role for the cerebellum, as it is not traditionally considered part of the global workspace. However, the cerebellum’s dense reciprocal connections with the cerebral cortex and subcortical structures imply that it could influence global neural states more than GWT acknowledges. Higher-Order Theories (HOTs) Higher-Order Theories (HOTs) of consciousness argue that consciousness arises from a higher-order representation of a mental state. While HOTs typically focus on cortical areas involved in generating these higher-order representations, the cerebellum’s involvement in cognitive and affective processes, such as those evidenced by cerebellar cognitive affective syndrome, suggests that it might contribute to the broader architecture of consciousness by modulating these higher-order processes. Directions for Future Research Empirical Studies Neuroimaging and Connectivity: Future research should employ advanced neuroimaging techniques to map the functional connectivity between the cerebellum, brainstem, and cerebral cortex. Understanding these pathways can shed light on how the cerebellum integrates sensory and motor information and its potential role in conscious processing. Cerebellar Agenesis Case Studies: Detailed longitudinal studies on individuals with cerebellar agenesis can provide insights into how the absence of cerebellar structures affects consciousness and self-perception, particularly focusing on the first-person perspective meaning of consciousness rather than its awake/aware connotation. Comparing cognitive and affective profiles with those of individuals with intact cerebellums can highlight the cerebellum's contributions to conscious experience. Split-Brain Research: Revisiting split-brain studies with a focus on the cerebellum's involvement can help determine whether this structure plays a role in maintaining unified consciousness. Experimentation should include tasks that require interhemispheric communication, potentially revealing cerebellar contributions to integrated conscious states. Theoretical Development Integrated Information Theory (IIT): Extending IIT to incorporate cerebellar functions could refine our understanding of how integrated information across neural networks contributes to consciousness. This includes developing models that account for the cerebellum’s potential role in minimizing prediction errors and maintaining neural coherence. Global Workspace Theory (GWT): Expanding GWT to include cerebellar contributions can help explain how information is broadcast across neural networks. This theoretical extension should consider how cerebellar inputs might influence the global workspace and contribute to conscious access. Higher-Order Theories (HOTs): Integrating the cerebellum into HOTs involves considering how cerebellar processes might support higher-order representations. This theoretical approach can explore how the cerebellum’s predictive functions and error correction mechanisms influence higher-order cognitive processes and conscious states. Broader Philosophical Implications The proposal that the cerebellum and brainstem play significant roles in consciousness challenges traditional views that primarily focus on the cerebral cortex. This shift has several philosophical implications: Redefining Consciousness If the cerebellum contributes to consciousness, we must reconsider definitions that limit conscious experience to cortical activities. This broader view necessitates a more inclusive understanding of the neural basis of consciousness. The Nature of the Self Exploring the cerebellum's role in maintaining a unified sense of self invites us to rethink the nature of personal identity. The cerebellum's involvement suggests that selfhood might be more complex than previously thought. Mind-Body Relationship The idea that consciousness might involve cerebellar and brainstem structures adds complexity to the mind-body problem. It suggests that consciousness arises from a more intricate interplay of neural processes, challenging simplistic dualistic or reductive materialist perspectives. Ethical Considerations Understanding consciousness as a distributed process involving the cerebellum and brainstem has ethical implications for medical practices. It could influence approaches to brain injuries, neurodegenerative diseases, and the development of brain-machine interfaces, emphasizing the need to preserve and support these regions in therapeutic contexts. Conclusion This exploration into consciousness, using telepresence as a metaphor, suggests that the cerebellum and brainstem may play central roles in the origins of consciousness. The cerebellum, often considered a mere motor coordinator, forms a stable sense of self and, together with the brainstem, contribute to a first-person perspective. Drawing a parallel between human-humanoid interaction in telepresence and cerebellum-cerebrum interaction within the brain highlights this idea. Just as the humanoid mistakenly believes its first-person perspective resides with it when it truly resides with the human operator, our first-person perspective, traditionally thought to reside in the cerebrum, might in fact originate in the cerebellum. This insight underscores the need for a comprehensive understanding of consciousness that considers all potential contributors, including the hindbrain. The potential roles of the cerebellum and brainstem in consciousness challenge traditional views. While research has explored these structures empirically and theoretically, future work should revisit their contributions afresh. This could offer broader philosophical insights into the first-person perspective, consciousness, and the mind-body relationship. An expanded view invites a more holistic approach, incorporating traditionally overlooked regions to develop a comprehensive theory of consciousness. “Modern neuroscience language has delicately shifted. What was the ‘seat of the soul’ is now the ‘seat of the self.’ New brain scanning methods provide evidence to ‘pinpoint the “seat of self-consciousness.” [in reference to the cerebellum] (Montgomery, Bodznick 2016). --- Glossary of Key Technical Terms (Alphabetical Order) Brainstem: The lower part of the brain that connects to the spinal cord, responsible for regulating vital body functions such as breathing, heart rate, and sleep. Callosotomy: A surgical procedure that severs the corpus callosum, the structure that connects the two hemispheres of the brain, often used to treat severe epilepsy. Cerebellar Agenesis: A rare condition where the cerebellum is absent from birth, leading to various motor and cognitive impairments. Cerebellar Cognitive Affective Syndrome: A condition characterized by impairments in cognitive functions, such as planning and verbal fluency, and affective functions, such as emotional regulation, due to damage or dysfunction of the cerebellum. Cerebellum: A part of the brain located at the back of the skull, responsible for coordinating voluntary movements, balance, and posture. It may also play a role in cognitive and emotional functions. Cerebello-Thalamic Pathways: Neural pathways that connect the cerebellum to the thalamus, which then relays information to the cerebral cortex. Cerebral Cortex: The outer layer of the brain's cerebrum, involved in complex brain functions such as thought, perception, and voluntary movement. Cortico-Ponto-Cerebellar Pathways: Neural pathways that connect the cerebral cortex to the pons and cerebellum, involved in coordinating motor control. Consciousness: The state of being aware of and able to think about one's own existence, thoughts, and surroundings. Used synonymously here with sentience and first-person perspective. Dissociation: The separation of certain mental processes from the conscious awareness, or the separation of consciousness from the physical body or brain location. Embryogenesis: The process by which the embryo is formed and develops, from fertilization to the fetal stage. Firing Patterns: The sequence and timing of electrical impulses generated by neurons, which are crucial for neural communication and brain function. First-Person Perspective: The subjective point of view of an individual, characterized by personal experiences and self-awareness. Global Workspace Theory (GWT): A theory that posits consciousness arises from the broadcasting of information across a global workspace in the brain, allowing for the integration and coordination of various cognitive processes. Higher-Order Theories (HOTs): Theories of consciousness that suggest conscious experience depends on higher-order representations of mental states, often involving self-awareness and reflection. Integrated Information Theory (IIT): A theoretical framework that proposes consciousness arises from the integration of information across a network of neurons, quantified as a value called phi (Φ). Phantom Limb Sensations: The feeling that an amputated or missing limb is still attached to the body and moving appropriately with other body parts. Philosophical Zombie: a being in a thought experiment in the philosophy of mind that is physically identical to a normal human being but does not have conscious experience. Philosophy of Mind: A branch of philosophy that studies the nature of the mind, mental events, mental functions, consciousness, and their relationship to the physical body, particularly the brain. Plasticity: The brain's ability to change and adapt due to experience, which includes changes in neural pathways and synapses. Predictive Model: A theory that the brain continuously makes predictions about sensory input and adjusts its actions based on the accuracy of these predictions. Predictive Processing Framework: A theory that suggests the brain constantly generates and updates a model of the environment to predict sensory inputs and minimize prediction errors. Qualia: The individual instances of subjective, conscious experiences, such as the redness of an apple or the pain of a headache. Somatosensory Cortex: The part of the sensory system concerned with the perception of touch, pressure, pain, temperature, and proprioception (the sense of the relative position of body parts). Subcortical Regions: Areas of the brain located below the cerebral cortex, including the cerebellum and brainstem, involved in various functions including emotion, memory, and basic life processes. Telepresence: A technology that allows a person to feel as if they are present in a location other than their true location, often by controlling a robot or avatar in the remote location. --- Declaration of Generative AI and AI-Assisted Technologies in the Writing Process During the preparation of this work, ChatGPT was used to improve language and readability. After using this tool/service, the content was reviewed and edited as needed and the author takes full responsibility for the publication's content. References Glickstein, M. ‘Cerebellar agenesis,’ Brain (1994), 117, 1209-1212. 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