The brain is a mysterious organ that has captivated scientists for centuries. Like an experienced conductor, it harmoniously orchestrates a symphony of thoughts, emotions, and memories. Despite its vast range of abilities, it is also vulnerable to injuries and disorders that can have devastating consequences. And yet, for all its fragility, it can adapt to heal itself. In the event of a stroke, the brain can rewire its neural pathways, enabling healthy tissue to regain the functions of the damaged area. Stanford neuroscientist David Eagleman investigates the remarkable property of plasticity, dubbed livewiring, in his book Livewired: The Inside Story of the Ever-Changing Brain. Through his own research and compelling storytelling, Eagleman offers a unique perspective on what makes humans, humans.
The brain can display remarkable resilience even in the most challenging of circumstances. Throughout the book, Eagleman presents numerous case studies that vividly illustrate both the tangible, harmful effects of neurological disorders and the brain’s incredible ability to recover. Consider, for instance, a six-year-old boy who loses an entire half of his brain in a hemispherectomy but eventually regains nearly complete function. However, to do this, Eagleman suggests that timing is key; a young girl raised in total isolation and darkness for the majority of her childhood unfortunately never gains the ability to live independently because she neither develops full social nor linguistic aptitudes, as this window of development, once missed, “is difficult or impossible to reopen” (Eagleman, 2020, p. 24). Eagleman challenges the notion that the brain is a hardwired, static organ, instead proposing that it is a shifting landscape capable of livewiring itself to the needs of its user.
Perhaps the most insightful aspect of Livewired is Eagleman’s thoughts on the future of neurotechnology and how it may fundamentally change the way we interact with our environment. He proposes that scientists and engineers can harness Mother Nature’s ingenious biological design to improve medical outcomes. His thought-provoking “what ifs” stimulate the reader to think more deeply and critically about the future of neurotechnology. What if a device could allow humans to replicate animals’ navigational use of magnetic fields? In addition to restoring limb function, what if brain-machine interfaces could be used to add a limb? Eagleman pioneers his own work in the field of sensory substitution, creating Neosensory, a revolutionary wristband that allows a Deaf user to experience speech through vibrations on the skin. Neosensory might even have additional applications; in aviation, it could someday enable a pilot to “feel” high-dimensional data about their plane, rather than simply relying on visual or auditory cues. With the ever-increasing complexity of modern aircrafts, such technology could revolutionize the flying experience and improve safety. As Eagleman highlights in Livewired, technology like Neosensory has the potential to reshape the way we perceive and interact with the world, emphasizing the importance of the environmental factors that shape our sensory experiences.
A traditional neuroscience textbook presents what is known, but Livewired ponders what is yet to be uncovered. One such area is sensory addition. We have and are even limited to, if you will, five senses: vision, hearing, taste, touch, and smell. Current technology exists in sensory substitution (for example, allowing the blind to use echolocation to navigate), but Eagleman questions whether new senses could be added together. We’ve seen countless examples of hearing taking over the visual cortex in blind patients. In fact, this real estate “can be taken over by many tasks, not just those of hearing” (Eagleman, 2020, p. 41). What if we could add new senses entirely? Would this dilute the quality of the existing ones that are now condensed into a smaller area of the brain? After all, there are only so many neurons available. If sensory addition were possible, how many senses could be added? From a more philosophical standpoint, could the addition of new senses fundamentally alter our perception of reality? How might it change the way we perceive and interact with the world around us? What implications might this have for our grasp of consciousness, free will, and the nature of our existence? Such questions can only be answered hypothetically in the given movement, but as Eagleman emphasizes, no question should be dismissed as impossible.
The key to great science is the ability to communicate it—Eagleman excels at this, presenting complex scientific concepts in a clear yet thought-provoking manner. Livewired will captivate amateurs and experts alike. As the mysteries of the three-pound lump between our ears continues to be unraveled, it is important to remember that there is so much more to discover. Just as Hubble's groundbreaking discoveries revolutionized human understanding of the universe, Eagleman's work is changing the way humans perceive the brain's remarkable adaptability, ushering in a new era of neurotechnology that holds immense potential for improving our lives and shaping our future.
I had the honor to host a live Ask Me Anything (AMA) with David Eagleman where we discussed his work, insights, and advice in neuroscience: https://www.youtube.com/watch?v=h-EXxDIj7wU.
References
Eagleman, D. (2020). Livewired: The Inside Story of the Ever-Changing Brain. Pantheon Books, Penguin Random House LLC.