The HOWPER project has significantly advanced our understanding of perception by challenging and overturning the dominant open-loop paradigm. Prior to this work, many models—both biological and artificial—assumed perception to be a mostly feedforward process. HOWPER demonstrated, through multiple experimental paradigms, that perception in humans and animals operates in a closed-loop fashion, where sensory input and motor actions continuously influence each other in real time. This represents a fundamental conceptual shift with broad implications for neuroscience, robotics, and cognitive science.
Key advances beyond the state of the art include:
• Empirical validation of closed-loop perception (CLP) in both vision and touch using dynamic, gaze- and motion-contingent experiments. These studies established not only that sensing is active and closed-loop, but that it stabilizes toward individual-specific motor-sensory steady states—a feature absent from open-loop models.
• Discovery of matched motor-sensory strategies, such as idiosyncratic tactile scanning patterns tailored to individual sensory thresholds, revealing a personalized and adaptive nature of perception not accounted for in existing models.
• Introduction of brain-brain and brain-world duality, extending CLP into a novel theory of cognitive structure that integrates social (digital) and sensual (analog) perceptual loops. This social-cognitive extension of perception theory repositions the mind as a non-physical, interaction-based construct—offering a fresh lens on longstanding philosophical debates such as the mind-body problem.
• Design and testing of novel biomimetic artificial perceivers based on CLP principles. These systems successfully employed active sensing and event-based coding to achieve robust perception in challenging conditions while maintaining low power consumption—significantly advancing the frontier of efficient autonomous machines.
• Validation of CLP in sensory substitution, where active-sensing devices (e.g. ASenSub) led to faster learning and more natural perceptual strategies than passive devices. This demonstrated practical translational potential for rehabilitation and assistive technologies, especially for visually impaired individuals.
• Revealing subcortical complexity in perception, including the discovery that complex sensorimotor integration occurs already at the brainstem level in rodents, emphasizing that perception is a multi-layered and embodied process beginning at early neural stages.
Taken together, these advances mark a departure from traditional theories that separate sensing and acting. HOWPER's results establish a new baseline for understanding perception as an active, circular, and embodied process, opening new avenues for both scientific inquiry and real-world applications in medicine and robotics.
