David Eagleman, a Stanford neuroscientist and author, revisits our understanding of the brain's incredible adaptability. He reveals how neuroplasticity allows for astonishing skills like echolocation in blind individuals. The discussion covers sensory substitution technologies that transform sensory experiences and how cognitive biases shape our decision-making. Eagleman also explores the limitations of AI cognition compared to human thought processes, emphasizing the philosophical significance of these differences. Plus, he introduces 'possibilianism' for exploring varied interpretations of existence.
David Eagleman emphasizes the brain's remarkable plasticity, illustrating how it can rewire itself to repurpose functions in response to new experiences.
Eagleman challenges the traditional view of compartmentalized brain function, showing that different regions can adapt roles based on sensory inputs and training.
Advancements in sensory substitution technologies, like Neosensory, reveal innovative ways to enhance sensory experiences for individuals with disabilities, showcasing practical applications of neuroscience.
Deep dives
Understanding Brain Plasticity
The concept of brain plasticity, or the brain's ability to adapt and change, is critical to understanding neurological function. Neuroscientist David Eagleman introduces the term 'live-wired' to describe how the brain constantly reconfigures itself based on new experiences, a concept that extends beyond traditional plasticity. For instance, Eagleman illustrates his point by explaining that a person can lose vision, resulting in the visual cortex being repurposed for other senses, such as hearing and touch. This adaptability allows individuals to absorb and respond to their environments in innovative ways, demonstrating the dynamic nature of the human brain.
The Brain's Flexible Organization
Eagleman argues against the conventional view of the brain being compartmentalized into specific areas for functions like vision and hearing. Instead, he suggests that the brain operates more flexibly, enabling different regions to adapt roles based on the sensory input available. An example he provides is that of blind individuals using echolocation, where the brain's visual cortex is activated through sound, showcasing the brain's ability to repurpose itself. This concept underlines the remarkable capacity of the brain to reassign tasks among its neurons, creating a more holistic view of brain function.
Echolocation and Sensory Substitution
Eagleman explores the fascinating phenomenon of echolocation, specifically how blind individuals can learn to navigate their environments using sound. He explains that through training, these individuals are able to interpret clicks or other sounds as echoes, allowing their brains to form a spatial understanding akin to vision. This ability highlights the brain's plasticity, as regions typically dedicated to processing visual information can adapt to process auditory stimuli instead. The implication is that with practice and the right conditions, the brain can effectively substitute one sense for another, revealing its extraordinary flexibility.
The Purpose of REM Sleep
Rapid Eye Movement (REM) sleep plays a significant role in brain function, particularly regarding the maintenance of sensory systems. Eagleman presents a novel theory that suggests REM sleep serves as a protective mechanism against the loss of sensory processing during periods of darkness. By stimulating the visual cortex with random activity during sleep, the brain ensures that it maintains its flexibility and readiness to process visual information upon awakening. This insight provides a compelling explanation for why dreaming occurs and why it is integral to cognitive health and sensory adaptation.
Innovations in Sensory Technology
Eagleman discusses advancements in technology that utilize sensory substitution to help individuals with disabilities. For instance, he highlights his work with Neosensory, which leverages vibrations to allow deaf individuals to 'hear' through their skin. This wristband vibrates based on sound frequencies and helps users develop their own interpretations of auditory stimuli through tactile feedback. Such innovations emphasize the potential for technology to create new pathways for sensory experiences, demonstrating how scientific understanding of the brain can lead to practical applications that dramatically improve quality of life.
David Eagleman upends myths and describes the vast possibilities of a brainscape that even neuroscientists are only beginning to understand. Steve Levitt interviews him in this special episode of People I (Mostly) Admire.
SOURCES:
David Eagleman, professor of cognitive neuroscience at Stanford University and C.E.O. of Neosensory.
