(extracted from article by Dr D. Gamon)
The Human Mind
We all know that brain science is hot. There are far more academic and medical journals devoted to brain research than ever before, and every week in the paper you can read about some reportedly groundbreaking findings claimed to turn our understanding of the brain, as it were, on its head.
Why is the brain such a hot topic these days? What's changed from fifty years ago?
New brain imaging technology — PET, MRI, and TMS — allows researchers to watch a working brain in action. For the first time, we can see exactly which parts of a brain light up while its owner conjugates irregular verbs or thinks about something scary. New techniques for mapping our genetic code — as used in the ambitious Human Genome Project — give us unprecedented insight into the biological underpinnings of mental illness and behavior. And the Prozac revolution — a society-wide experiment in the manipulation of those brain-messenger chemicals known as neurotransmitters — has brought about a sea-change in the way both scientists and the rest of us think about human personality and identity. More is now known about neurotransmitters, and the kinds of emotional and mental states they influence, than ever before.
These are some of the things that the new brain science is bringing to the dinner table, and that we will be discussing in future columns:
• New studies have overturned the long-established dogma that adult brains don’t grow new brain cells. Recent research by neurobiologist Fred Gage at La Jolla’s Salk Institute show that your hippocampus — a brain structure crucial to acquiring new skills — continues to generate neurons throughout life. Not only that, but Gage and Princeton's Elizabeth Gould have shown that you can double the chances of survival of those new brain cells by challenging yourself with mental and physical exercise. “Use it or lose it” applies to your brain as well as the rest of your body.
• A molecule called CREB switches on the production of proteins to form pathways linking brain cells. On a structural level, that's what a long-term memory is. The reason not every experience gets coded as a permanent memory is that CREB has a twin — call it anti-CREB — that normally switches off the protein-synthesis process; that way, your brain isn't overwhelmed with memories of every trivial experience you've ever had. Since the CREB molecule has a longer life than anti-CREB, though, repeated, closely-spaced exposure to a stimulus allows the CREB levels to rise above those of anti-CREB, so that long-term memories are formed. That's why practice and repetition are a good way to learn something new. Now that the details of this process are understood, it's theoretically feasible to create a drug that will act as a short-term poison of anti-CREB — so that you can memorize whatever you want, with no effort or practice. You can bet that med students will be using this drug before the FDA approves it.
• Your brain's neurotransmitter systems shape your emotions, mood, and personality. Drugs such as Prozac manipulate your neurotransmitter levels and influence your outlook on life. For the first time in human history, looking at life through the eyes of someone with a more optimistic and outgoing temperament is as easy, and seemingly risk-free, as taking an aspirin.
• Advances in DNA mapping are helping to define the biological contribution to intelligence, personality, and behavior. Your DNA may code for either of two versions of a “novelty-seeking” gene, for example, one of which predisposes you to the temperament of a fearless explorer, while the other makes it more likely you'll be cautious and conservative about new experiences. In principle, such aspects of human personality may now be influenced through genetic manipulation.
• The interaction of mood with other body systems — your heart and immune system, for example — is now established science rather than just new-age hocus-pocus. The Cartesian divide between mind and body is rapidly disappearing.
• All these advances, in fact, move the brain out of the mysterious “black box” realm towards the status of just another part of the body, to be studied and understood like any other. And so many of these findings offer the prospect of an unprecedented control over our mental organ.
• At the same time, all of these practical applications of brain science raise challenging philosophical questions as well. Just as we've had to struggle with the consequences of our power to manipulate the external environment, so too will we now have to deal with issues arising from the fact that we have enough knowledge to manipulate our internal environment — without yet knowing quite enough about the brain to understand what unforeseen consequences might follow. And of course, scientific knowledge does not automatically translate into the wisdom to use that knowledge well. We'll all be grappling with these practical and philosophical issues for years to come.
The Human Mind
We all know that brain science is hot. There are far more academic and medical journals devoted to brain research than ever before, and every week in the paper you can read about some reportedly groundbreaking findings claimed to turn our understanding of the brain, as it were, on its head.
Why is the brain such a hot topic these days? What's changed from fifty years ago?
New brain imaging technology — PET, MRI, and TMS — allows researchers to watch a working brain in action. For the first time, we can see exactly which parts of a brain light up while its owner conjugates irregular verbs or thinks about something scary. New techniques for mapping our genetic code — as used in the ambitious Human Genome Project — give us unprecedented insight into the biological underpinnings of mental illness and behavior. And the Prozac revolution — a society-wide experiment in the manipulation of those brain-messenger chemicals known as neurotransmitters — has brought about a sea-change in the way both scientists and the rest of us think about human personality and identity. More is now known about neurotransmitters, and the kinds of emotional and mental states they influence, than ever before.
These are some of the things that the new brain science is bringing to the dinner table, and that we will be discussing in future columns:
• New studies have overturned the long-established dogma that adult brains don’t grow new brain cells. Recent research by neurobiologist Fred Gage at La Jolla’s Salk Institute show that your hippocampus — a brain structure crucial to acquiring new skills — continues to generate neurons throughout life. Not only that, but Gage and Princeton's Elizabeth Gould have shown that you can double the chances of survival of those new brain cells by challenging yourself with mental and physical exercise. “Use it or lose it” applies to your brain as well as the rest of your body.
• A molecule called CREB switches on the production of proteins to form pathways linking brain cells. On a structural level, that's what a long-term memory is. The reason not every experience gets coded as a permanent memory is that CREB has a twin — call it anti-CREB — that normally switches off the protein-synthesis process; that way, your brain isn't overwhelmed with memories of every trivial experience you've ever had. Since the CREB molecule has a longer life than anti-CREB, though, repeated, closely-spaced exposure to a stimulus allows the CREB levels to rise above those of anti-CREB, so that long-term memories are formed. That's why practice and repetition are a good way to learn something new. Now that the details of this process are understood, it's theoretically feasible to create a drug that will act as a short-term poison of anti-CREB — so that you can memorize whatever you want, with no effort or practice. You can bet that med students will be using this drug before the FDA approves it.
• Your brain's neurotransmitter systems shape your emotions, mood, and personality. Drugs such as Prozac manipulate your neurotransmitter levels and influence your outlook on life. For the first time in human history, looking at life through the eyes of someone with a more optimistic and outgoing temperament is as easy, and seemingly risk-free, as taking an aspirin.
• Advances in DNA mapping are helping to define the biological contribution to intelligence, personality, and behavior. Your DNA may code for either of two versions of a “novelty-seeking” gene, for example, one of which predisposes you to the temperament of a fearless explorer, while the other makes it more likely you'll be cautious and conservative about new experiences. In principle, such aspects of human personality may now be influenced through genetic manipulation.
• The interaction of mood with other body systems — your heart and immune system, for example — is now established science rather than just new-age hocus-pocus. The Cartesian divide between mind and body is rapidly disappearing.
• All these advances, in fact, move the brain out of the mysterious “black box” realm towards the status of just another part of the body, to be studied and understood like any other. And so many of these findings offer the prospect of an unprecedented control over our mental organ.
• At the same time, all of these practical applications of brain science raise challenging philosophical questions as well. Just as we've had to struggle with the consequences of our power to manipulate the external environment, so too will we now have to deal with issues arising from the fact that we have enough knowledge to manipulate our internal environment — without yet knowing quite enough about the brain to understand what unforeseen consequences might follow. And of course, scientific knowledge does not automatically translate into the wisdom to use that knowledge well. We'll all be grappling with these practical and philosophical issues for years to come.
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