The hands of time: Moving my body to keep time order in the brain
Abstract
The brain is very often viewed as a network, be it at small scale made of cells, mostly neurons, or at larger scale made of neuronal assemblies. Here we introduce a conjecture, in the spirit of a philosophical though experiment, which proposes that the present cannot be obtained from within such networks, and that this limitation imposes burdens on network efficiency in information processing. We aim to argue this conjecture imposes recurrent contacts from within the brain to outside in the physical world via behavior, which create a flow of time stamps. This though experiment may contribute to make the divide between the foci toward inside versus outside, for example opposing ecological psychology and many frameworks adopted in neurosciences, superfluous. This piece proposes an ambulation triggered by a thought experiment: What if I was a neuron listening to another one and talking to a third? It is a modest attempt to walk in the footsteps of classical thought experiments, like Molyneux problem, the imitation game and the anti-sequel Chinese room, key gedankenexperiments in an elevator in physics, or the cogito in philosophy.
Summary
This paper presents a thought experiment exploring how the brain maintains a sense of temporal order ("t-present") within neural networks, given the inherent delays in neuronal communication. The author proposes that internal network dynamics alone are insufficient to establish a unique "present" due to these delays, leading to temporal ambiguity. This is illustrated using a simplified model of three interconnected neurons arranged in a ring with delayed connections. The core argument is that physical interaction with the environment, through body movement and sensory feedback, provides the necessary "timestamps" to resolve this ambiguity and ground the brain's internal activity in the external world. This conjecture aims to bridge the gap between ecological psychology, which emphasizes the organism-environment relationship, and network neuroscience, which often focuses on internal brain processes. The methodology involves a theoretical analysis based on a thought experiment and a simplified neural network model. The model consists of three interconnected nodes with delayed connections, and the author explores the consequences of these delays on the network's ability to establish a consistent temporal order. The paper argues that without external reference, the network's internal dynamics are insufficient to define a unique "present," and that physical interaction with the environment provides the necessary timestamps to resolve this ambiguity. The key contribution is the proposal that embodied action serves as a fundamental mechanism for grounding the brain's internal activity in the external world and maintaining a sense of temporal order. This matters to the field because it challenges the purely internalist view of brain function and highlights the importance of considering the organism-environment relationship in understanding cognition and perception.
Key Insights
- •The paper posits that delays in neural communication within a closed network create an intrinsic ambiguity in temporal ordering, preventing the network from establishing a unique "present" based solely on internal dynamics.
- •The thought experiment suggests that shifting the timeframe origin for each node in a ring network highlights the ambiguity, as the present cannot be uniquely determined from within the network itself.
- •The paper draws an analogy between the brain's temporal ordering problem and the sensor fusion and synchronization challenges in distributed sensor networks, where external triggers or timestamps are required.
- •The proposed solution involves embodied action, where physical interaction with the environment provides the necessary "timestamps" to resolve temporal ambiguity and anchor the brain's internal activity in the external world.
- •The paper connects this idea to embodied timing, where behavior is used to maintain timing, and suggests that various actions like reaching, postural adjustments, and rhythmic movements can provide temporal anchors.
- •The author acknowledges that the work is speculative and presents it as an opinion piece, emphasizing the need for further research to test the hypothesis.
- •A limitation is the lack of explicit mathematical modeling to support the thought experiment. While the paper introduces delayed differential equations (DDEs), it doesn't provide specific simulations demonstrating the temporal ambiguity and the resolving power of external interaction.
Practical Implications
- •The research suggests that interventions targeting perception-action coupling may be beneficial for individuals with motor disorders, such as Parkinson's disease, where sensory-motor integration is impaired.
- •Practitioners could explore how manipulating sensory feedback during movement tasks affects temporal perception and cognitive performance.
- •Future research could investigate the neural mechanisms underlying the integration of sensory feedback and internal network dynamics in maintaining a sense of temporal order. This could involve neuroimaging studies examining brain activity during tasks that require precise timing and sensory-motor coordination.
- •This work opens up a new perspective on the role of embodiment in cognition and perception, suggesting that physical interaction with the environment is not just a means of acting in the world, but also a fundamental mechanism for structuring our experience of time.
- •Future research could focus on developing more detailed computational models of the proposed mechanism, incorporating realistic neural dynamics and sensory feedback.