"By doing that, we were able to double the rate of learning."
Is technology a good or a bad thing? A question that everyone has an opinion on, and it's mostly negative these days. But it's such a nuanced answer that it's difficult to have a truly informed opinion on.
The purpose of this new section on technology in Killing Buddha is to have a more informed opinion on that question. I want to know how technology affects our day-to-day life. We've become so used to its impact that it's difficult to truly see its effects. I'd also like to see how future technologies could affect us.
I will be interviewing people at the forefront of technology, psychologists and philosophers who can talk about the impact of technology on our everyday lives.
For its inaugural interview, I spoke to Dr. Michael Weisand of Rio Grande Neurosciences. He is at the forefront of research using transcranial direct-current stimulation (TDCS), a technology that applies electrical stimulation to the brain. His lab has managed to double the rate of learning in subjects. Needless to say, this technology has enormous potential.
Check out Radiolab's coverage of it here.
In this part of the interview, we spoke about the current day uses of TDCS. In the second part, we spoke about the distant future uses of this technology.
I hope you guys enjoy.
What is transcranial direct-current stimulation (TDCS)?
The brain is an electrical organ, so you're able to apply electricity to influence the operation of that electrical organ.
At our organization, we map the parts of brain that are different when you are feeling one way versus feeling another way. Then we mathematically subtract those two separate brain states and we use that to design a paradigm so we can apply electricity in the brain in the correct places. Then we can influence the electrical activity that underlies those brain states.
So let's say we map your brain activity when you're attentive. Then we map your brain activity again when you are inattentive. Then we mathematically subtract those two states. Now we know parts of your brain that act differently during an attentive state and an inattentive state. Now we can target that piece of brain that controls attentiveness.
"I also think you will see people use TDCS to treat dementia and mood disorders like depression or bipolar disorder."
Can you give a brief summary of some of the biggest discoveries in TDCS research?
One of the big applications that we're looking in our lab is learning.
We found the parts of the brain, especially down in the temporal lobes, that were acting differently when you were naïve and when you were an expert. So we used that information to design a paradigm to pass electricity through the temporal lobe to increase activity as you learn. And by doing that, we were able to double the rate of learning.
There are lots of other laboratories that are looking into enhancing sleep, enhancing attention, improving depression and dementia. Learning is just the tip of the iceberg.
Have there been any studies looking into the permanence of these effects?
I don't think there's a special quality to memories that are formed under the influence of TDCS. So it'll last just like any other memory. Electrical brain stimulation simply aids in setting the conditions that makes forming memories more likely.
What do you see as some of the most promising uses of this technology over the next five years?
In the next five years, you'll see people successfully using TDCS for rehabilitation after stroke or brain trauma. I also think you will see people use TDCS to treat dementia and mood disorders like depression or bipolar disorder.
Can you tell me how it would affect dementia?
Dementia is essentially similar to a learning disorder in that the physical network that supports the acquisition of information is degraded or the amount of neurotransmitters released is less than usual. In either case, you can apply electrical stimulation to increase the release of neurotransmitters. Or you can apply electrical stimulation to build or fortify physical networks that support memories.
"If you apply stimulation, you cause action potentials in the cells in the brain stem, and thus release neurotransmitters to a large portion of the neocortex. It's very likely that you will influence mood in the same way that an SSRI would."
And how does TDCS affect your mood?
One thing we know about depression is that you can improve your mood if you cause more mono-amine neurotransmitters (dopamine, norepinephrine and serotonin) to be released.
The monoamines system in the brain is laid out like a sprinkler system. There is a cluster of cell bodies in the brain stem, and when they become active, they release neurotransmitters to very large portions of the neocortex.
If you apply stimulation, you cause action potentials in the cells in the brain stem, and thus release neurotransmitters to a large portion of the neocortex. It's very likely that you will influence mood in the same way that an SSRI would.
In the case of memories, the more times you activate them, and so the longer they will last. But I don't believe that is true in the case of mood.
So do you think there are any permanent effects of using TDCS on your mood?
Short answer is that I don't know, and it's difficult to speculate.
Mood is much more transient than memories. Let's say it takes ten days to learn something, you might be able to reduce that period of learning to seven or five days using TDCS. But with mood, you can be happy and sad within the same ten minute period.