Perchance to Dream
YOU ARE JOLTED AWAKE FROM a terrifying nightmare. Your pulse is rapid, breathing shallow. Beads of sweat roll off your forehead into the soaked pillow clutched tightly in your clenched fist. It is dark. You're disoriented. The nameless fear that almost nabbed you in its jaws moments ago quickly fades out of focus and into a fuzzy, distant memory. As the seconds pass, the receding terror is replaced by a growing awareness of where, and who, you are. You are lying safe in your bed in the middle of the dark night. You slowly become aware of your surroundings: the yielding warm sheets, the dim red glow cast by the surrounding constellation of electronic devices in "sleep" mode, and the soft, gentle breaths of your loved one lying next to you, still fast asleep. You take a deep breath and try to distract your mind with happier thoughts in an attempt to ease yourself back to sleep.
This is likely a familiar, though hopefully infrequent, scenario to most of us. Psychologists, psychoanalysts in particular, have long been interested in the interpretation of dream states and what they say about the dreamer and his or her subconscious. Cognitive psychologists, on the other hand, have had a long-standing fascination with our wakeful mind and its processes. But what about the transition from dream state to full wakefulness? How do we explain, from a scientific point of view, this transition from sleep to consciousness? And more importantly, what can an understanding of its neural basis tell us about how brains "do mind"?
These questions and more are the subject that Dr. Antonio Damasio, a cognitive neuroscientist at the University of Southern California, explores deeply and thoroughly in Self Comes to Mind. Damasio provides a compelling big picture account of how our consciousness — and, more importantly, our sense of self — is a product and a process of our human brain. The picture he meticulously details relies on the disparate but connected disciplines of behavioral neuroscience, from comparative psychology and brain evolution to the intricacies of cutting-edge research — much from his own lab — on human cognitive neuroscience and neurology.
Before we begin, let's revisit the opening scenario. As we awaken from sleep, our consciousness undergoes a radical transformation composed of dramatic adjustments in neural processes. Some neural circuits go quiet while others come online. The entire orchestration of the symphony of mind unfolds like changes in a music score, and while there is no single, master conductor, Damasio posits that the decentralized process does have hot spots of top-down modulation linked by connections built over evolutionary time. These "command centers," for lack of a more accurate but succinct term, do one thing really well: They create our sense of self, our sense of being a protagonist in a continuously unfolding nonlinear narrative through which we can travel again and again in our memories and plan possible and even impossible futures. These circuits have been specially designed by natural selection to work with the rest of our perceptual, attentional, and memorial machinery to allow us incredible feats of counterfactual reasoning, from mere day dreaming ...read more