Translator:
Reviewer: Denise RQ Right now, standing on this stage, by speaking these words, I'm changing your brain. And I know, it sounds like a superpower (Laughter) but you have it, too, you're changing my brain
just by being here. Now, it all hinges on
the single most important thing that I've ever learned
as a clinical neuroscientist, and here it is: experience
changes the brain. Your brain is exquisitely designed to respond, to adapt
to every experience you'll ever have, every thought, emotion,
action, perception, all of it leaves an impact on your brain. This simple insight can completely reshape our intuitions about mental illness
and about chemical imbalance, and at the same time, it yields
some simple and elegant lifehacks any of us can use
to enhance brain function. So let's see how this works. Today we're all gathered to bask
in the warm glow of TED. Unfortunately, our bodies, your bodies,
will spend most of this time just sitting, and that's a problem
because as you might have heard sitting is the smoking of our generation. (Laughter) Physical inactivity
doesn't just take a toll on our hearts, our lungs,
and yes, our fat cells, it also takes a toll on the brain. Now, when we're physically active, key circuits use neurotransmitters like dopamine and glutamine and serotonin; they start to light up in pathways
scattered throughout the brain, enhancing energy,
and mood, and motivation. It's one of the major reasons why exercise
is proven to be a potent antidepressant. So, two landmark clinical trials
at Duke University: researchers had the audacity to test
exercise head to head against Zoloft. (Laughter) They found 30 minutes of brisk walking
just three times a week was every bit as effective as the medication
in fighting clinical depression. 30 minutes, brisk walking. Three times a week. Lifehack. And then, when the researchers revisited
those same patients, one year later, they found the patients
who had kept on exercising, those were the ones
that were most likely to stay well. They didn't see
any similar protective benefit of just staying on medication. It turns out, exercise also enhances
our cognitive function, it improves memory,
and attention, mental clarity; it even helps keep your brain young by triggering the growth
of new brain cells. So let me put it simply:
exercise it's medicine. And I mean that quite literally. It enhances brain function
as powerfully as any medication. And trust me, if big pharma
could somehow capture the neurochemical benefit of exercise (Laughter) - can you see it? - put it in a pill and then sell it to you, they would do it in a heartbeat. And then, they would finally have a blockbuster drug completely free
of any difficult side effects like weight loss or weight gain, sedation, emotional blunting, loss of libido. OK, let's take another example. This one's maybe more risky. Instead of sitting here,
in this darkened auditorium what if you were to get up, walk outside and bask in sunlight? The instant you stepped outside, specialized receptors in your retina
in the back of the eye would kick off an avalanche
of neurological activity. These receptors have
a broadband connection to body clock circuitry
buried deep inside the brain. These are circuits that regulate
your sleep, and appetite, and arousal, and hormone levels. And for millions of Americans
and Europeans every winter, when the days turn cold,
and bleak, and short, at least here in Kansas, sunlight deprivation causes
all hell to break loose in the brain. And the result is an episode of debilitating, painful,
seasonal affective disorder. It's been discovered up to 30% of us will have
some symptoms every winter, and anyone of us can have a decrease,
a drop in serotonin-based signaling any time
we're chronically sunlight deficient, any time
we're chronically deprived of sunlight. So, if that happens to you,
if that happens to me, what should we do about it? We could always try medication, after all, one out of every five Americans takes a psychiatric drug every single day. There's been a 300% increase
in antidepressive use just in the last 20 years. And it raises
a really interesting question: with all this medication,
with this huge increase, why is it that there's been
no corresponding decrease in the rate of depression
in the last 20 years? Have you ever wondered about that? How do we still have
an epidemic of this illness? I believe the answer is straightforward: you and I were never designed for a sedentary, indoor, sleep deprived, socially isolated, fast food laden, frenetic pace of modern American life. Experience changes the brain, and our epidemic of depression it's driven by an even greater epidemic
of unhealthy experience. For the past seven years, my clinical research group
has been working to help depressed patients
change the way they live, to get the exercise they need,
to get the sunlight they need. And when that's not available,
we do have a lifehack, and you can see it: it's a therapeutic light box that simulates the effects
of sunlight on the brain, its effects, its benefits, typically
kick in within five to seven days; where medication,
do you know how long? It often takes about three to four weeks
before it starts to work. Now, what we eat
also matters to the brain. Sugar; it turns out sugar lights up
the brain's reward circuitry about as effectively as cocaine (Laughter) and it's just about as addictive, and unfortunately,
it also triggers the release of powerful inflammatory hormones that disrupt normal chemical signaling
throughout the brain. And it's a huge problem because the average American now consumes
22 teaspoons worth of added sugar every single day. Most of us would do well to cut back,
and to cut way back. And then, finally, what we think about
also matters to the brain. Have you heard of rumination? It's the habit of dwelling
on our negative thoughts repeatedly, at length. It ramps up our brain's stress circuitry, and that, in turn, interferes with
the whole process of memory consolidation. It's the big reason
why memory tends to suffer whenever we're stressed and we get trapped
inside our own heads. And the research shows we're most likely to ruminate
whenever we're completely alone. On the other hand, face time
with our loved ones it doesn't just protect us
against toxic rumination, it also directly puts the breaks
on the brain's stress response. And the benefits can range
from lower anxiety to better quality of sleep,
to yes, better memory. Now, whenever we hear the term
'chemical imbalance,' most of us, I think, reflexively assume
medication must be the answer. Yet, the relevant neuroscience leads us
to a somewhat different conclusion: there are many different ways
of changing neurochemistry, most of them have nothing
to do with medication. That's why I believe, in the long run, the most effective way of balancing
neurochemistry is to balance our lives. Remember, experience changes the brain. Thank you. (Applause)
