In The Tell-Tale Brain: A Neuroscientist’s Quest for What Makes Us Human (2010), award-winning neuroscientist V.S. Ramachandran explores various aspects of brain structure and functions. His approach to science is unique: Ramachandran studies patients with neurological disorders to better understand normal, healthy brains. He believes in simple, low-tech and easily-replicated experiments. While the book delves into complex topics, such as phantom limb syndrome and autism, Ramachandran uses case studies and research to illuminate the mysteries of the human mind, making the work accessible to a broader audience. Through Ramachandran’s quest, he attempts to address larger questions about what makes humans unique compared with other primates, including language, culture, art, and the concept of self.

The Tell-Tale Brain was a New York Times bestseller and won the 2010 Vodafone Crossword Book Award (Non-Fiction). It has generally received positive reviews, although some critics note it is difficult to tell when Ramachandran is discussing an idea grounded in solid science or speculation.

This study guide uses the 2012 Norton paperback edition.

Summary

In the Introduction, Ramachandran explores the various perspectives on human uniqueness, beginning with Victorian-era intellectuals. These intellectuals debated whether humans were unique compared with apes. Debates around human uniqueness continue today. Ramachandran argues that humans are unique: Humans are the only species to control their own destiny. Ramachandran also offers a primer on human brain anatomy. The brain houses nearly 100 structures comprised of networks of neurons. These structures control unique cognitive or physiological functions. Damage to structures causes neurological disorders.

In Chapter 1, Ramachandran discusses his early work with phantom limbs, which are a unique phenomenon where patients still feel sensation in the limb that has been amputated. By working with patients using simple, low-tech methods (e.g., Q-tips, water, and mirrors), Ramachandran unlocks two mysteries about the brain. First, the human brain can rewire and adapt throughout a person’s life, known as “neuroplasticity.” Second, the brain views perception as reality. People still feel their limbs even though they have been removed. Ramachandran utilizes this important feature of the brain to trick the brain into unlearning pain and paralysis associated with phantom limbs. Ramachandran also explores the origin of human laughter and smiles, suggesting they helped our early ancestors known when a perceived threat was false.

Next, Ramachandran turns to how the brain processes visual information and what makes human visual processing unique compared with other primates in Chapter 2. His central tenet is that vision happens in the brain rather than the eyes. Moreover, perception is a uniquely human characteristic. Ramachandran illustrates the difference between visualization and perception through discussions of optical illusions. He also discusses several clinical studies in which damage to the visual processing parts of the brain leave vision untouched, but skew people’s perception. As one example, after suffering a stroke, a woman named Ingrid could no longer perceive motion. She became terrified of crossing streets since moving cars looked like strobe lights to her. Other patients lost the ability to recognize faces and objects.

The subject of Chapter 3 is synesthesia, a perceptual experience where two senses become blended. Synesthetes describe numerous abilities, including visualizing emotion, seeing colors in numbers, and tasting colors. Ramachandran has spent a substantial part of his career investigating this phenomenon. Through his work, he shows several key findings. First, synesthesia is real. Second, neural cross-wiring caused by a mutant gene likely explain what is going on in the brain. Finally, evolution has not removed synesthesia because it confers an advantage: It drives human progress by making some people more creative. Ramachandran also suggests that synesthesia might help neuroscientists eventually understand human consciousness, which remains one of the most elusive human traits.

Ramachandran turns to mirror neurons in Chapters 4-6. While mirror neurons are found in all primates, they are particularly sophisticated in humans. They enable humans to imitate, to adopt another person’s perspective, and to empathize. These are all unique human traits. Ramachandran argues that mirror neurons played a key role in humankind’s creation of culture.

In Chapter 5, Ramachandran suggests autism, which is a developmental disorder, might stem from deficiencies in mirror neurons. Autistic individuals have difficulty with unique human traits, including empathizing, learning languages, and imitation. Experiments using electroencephalography (EEG) suggest patients with autism show less neuron activity than their non-autistic counterparts. Ramachandran also suggests that a distorted salience landscape might also partially explain autism. Since autism appears to impact a patient’s very sense of self, Ramachandran believes studying the disorder might help us better understand the nature of consciousness.

In Chapter 6, Ramachandran presents a novel idea for the evolution of language. He does not believe language evolved for communication, primarily because the three main aspects of language—syntax, semantics, and lexicon—are all distinct and independent of one another. Rather, Ramachandran suggests that language emerged, like synesthesia, as a byproduct of cross-wiring in the human brain (which he calls “synesthetic bootstrapping theory”). To Ramachandran, language is the most glorious attribute that defines humankind.

Ramachandran turns to how we can use science to study beauty and aesthetics in Chapters 7 and 8. In Chapter 7, he explains the difference between aesthetics and art (aesthetics are universal across culture and species; art is unique to humans) and establishes what he considers the nine laws of aesthetics. He discusses the first two laws: the law of grouping and the law of peak shift. In Chapter 8, he turns to the remaining laws: contrast, isolation, peekaboo or perceptual problem solving, abhorrence of coincidences, orderliness, symmetry, and metaphor. He attempts to identify what is going on in the brain with these laws. The laws in Chapter 8 are not as well-studied; thus, he speculates more in this chapter about their evolutionary origin and the brain mechanisms behind them.

Finally, Chapter 9 focuses on the concept of self. He dispels the myth that humans have one unitary self. Instead, the self consists of seven components: unity, continuity, embodiment, privacy, social embedding, free will, and self-awareness. He provides many case studies about specific neurological disorders that disrupt one of these conditions, therefore disrupting a person’s sense of self.

Ramachandran ends the book by cautioning readers against the false notion that Earth was created for humans (Epilogue). While there are still many mysteries left regarding the human brain, this is not one of them. Ramachandra hopes that neuroscience will continue to incorporate a variety of methods and perspectives (including his own) to uncover the mysteries of the human brain and human uniqueness.