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"You may think you decided to read this story -- but in fact, your brain made the decision long before you knew about it. In a study published Sunday in Nature Neuroscience, researchers using brain scanners could predict people's decisions seven seconds before the test subjects were even aware of making them. The decision studied -- whether to hit a button with one's left or right hand -- may not be representative of complicated choices that are more integrally tied to our sense of self-direction. Regardless, the findings raise profound questions about the nature of self and autonomy: How free is our will? Is conscious choice just an illusion? "Your decisions are strongly prepared by brain activity. By the time consciousness kicks in, most of the work has already been done," said study co-author John-Dylan Haynes, a Max Planck Institute neuroscientist. Haynes updated a classic experiment by the late Benjamin Libet, who showed that a brain region involved in coordinating motor activity fired a fraction of a second before test subjects chose to push a button. Later studies supported Libet's theory that subconscious activity preceded and determined conscious choice -- but none found such a vast gap between a decision and the experience of making it as Haynes' study has. In the seven seconds before Haynes' test subjects chose to push a button, activity shifted in their frontopolar cortex, a brain region associated with high-level planning. Soon afterwards, activity moved to the parietal cortex, a region of sensory integration. Haynes' team monitored these shifting neural patterns using a functional MRI machine. Taken together, the patterns consistently predicted whether test subjects eventually pushed a button with their left or right hand -- a choice that, to them, felt like the outcome of conscious deliberation. For those accustomed to thinking of themselves as having free will, the implications are far more unsettling than learning about the physiological basis

"A few months ago, a construction worker named Wesley Autrey leapt in front of a moving subway train in New York City to save a stranger who had just collapsed onto the tracks. Five days later, the New York Times speculated that this act of apparent altruism-"I just saw someone who needed help," Autrey said-might be explained by a bunch of cells thought to exist in the human brain, called mirror neurons. The idea that these particular cells might underlie a fundamental human impulse reflects the emergence of a new scientific myth. Like a traditional myth, it captures intuitions about the human condition through vivid metaphors. This isn't the first time that popular science has merged with the popular imagination. In the 1960s, for example, pioneering work on "split-brain" patients revealed real functional differences between the two cerebral hemispheres-an idea that quickly became a metaphor for ancient intuitions about reason and passion. Advertisement Mirror neurons have become the "left brain/right brain" of the 21st century. The idea that these cells could make a hero out of Wesley Autrey began with a genuine and important discovery about the brains of macaque monkeys. In the late 1980s and early 1990s, neuroscientists found a population of cells that fired whenever a monkey prepared to act but also when it watched another animal act. They called these cells "mirror neurons." It didn't take long for scientists and science writers to speculate that mirror neurons might serve as the physiological basis for a wide range of social behaviors, from altruism to art appreciation. Headlines like "Cells That Read Minds" or "How Brain's 'Mirrors' Aid Our Social Understanding" tapped into our intuitions about connectedness. Maybe this cell, with its mellifluous name, gives us our special capacity to understand one another-to care, to learn, and to communicate. Could mirror neurons be responsible for human language, culture, empathy, and morality? "

"Brain research is beginning to produce concrete evidence for something that Buddhist practitioners of meditation have maintained for centuries: Mental discipline and meditative practice can change the workings of the brain and allow people to achieve different levels of awareness. Those transformed states have traditionally been understood in transcendent terms, as something outside the world of physical measurement and objective evaluation. But over the past few years, researchers at the University of Wisconsin working with Tibetan monks have been able to translate those mental experiences into the scientific language of high-frequency gamma waves and brain synchrony, or coordination. And they have pinpointed the left prefrontal cortex, an area just behind the left forehead, as the place where brain activity associated with meditation is especially intense. "What we found is that the longtime practitioners showed brain activation on a scale we have never seen before," said Richard Davidson, a neuroscientist at the university's new $10 million W.M. Keck Laboratory for Functional Brain Imaging and Behavior. "Their mental practice is having an effect on the brain in the same way golf or tennis practice will enhance performance." It demonstrates, he said, that the brain is capable of being trained and physically modified in ways few people can imagine. Scientists used to believe the opposite -- that connections among brain nerve cells were fixed early in life and did not change in adulthood. But that assumption was disproved over the past decade with the help of advances in brain imaging and other techniques, and in its place, scientists have embraced the concept of ongoing brain development and "neuroplasticity." "