Skip to main content

How to 'take over' a brain

By Leonard Mlodinow, Special to CNN
January 7, 2013 -- Updated 1614 GMT (0014 HKT)
STORY HIGHLIGHTS
  • Leonard Mlodinow: In 2013, "optogenetics" is the technology to watch out for
  • Mlodinow: Imagine being able to turn neurons in a brain on and off from the outside
  • He says optogenetics can be used to gain insights on diseases, mental illnesses
  • Mlodinow: It will change the way we understand ourselves as human beings

Editor's note: Leonard Mlodinow is the author, most recently of, "Subliminal: How Your Unconscious Mind Rules Your Behavior." He teaches at California Institute of Technology.

(CNN) -- The hottest field in science this past decade has been neuroscience. That explosion in research, and our understanding of the human brain, was largely fueled by a new technology called functional magnetic resonance imaging (fMRI) that became widely available in the 1990s. Well look out! Another technology-based neuroscience revolution is in the making, this one perhaps even bigger. The term to watch for in 2013 is "optogenetics." It's not a sexy term, but it is a very sexy technology.

The heritage of optogenetics goes way back to 1979, when Nobel Laureate Francis Crick, co-discoverer of the structure of DNA with James Watson and Rosalind Franklin, suggested that neuroscientists should seek to learn how to take control of specific cells in the brain. Well, that certainly would seem to be an advance with great potential. Imagine being able to turn the neurons in an animal's brain on and off from the outside. Sounds like you'd be turning the creature into a robot, sounds like science fiction. Right?

Well, flash forward thirty-some years, and guess what, optogenetics is a reality! Here's how it works... roughly. An obvious approach would be to stick a tiny electrode into an animal's brain and stimulate the cells using electricity.

Leonard Mlodinow
Leonard Mlodinow

Today we have tiny microelectrodes, but they are still too crude for the job. Crick speculated that light could be the tool to use. That turned out to be true: Optogenetics involves inserting fiber-optics tools into an animal's brain, in order to control the target neurons using pulses of light as a trigger.

Become a fan of CNNOpinion
Stay up to date on the latest opinion, analysis and conversations through social media. Join us at Facebook/CNNOpinion and follow us @CNNOpinion on Twitter. We welcome your ideas and comments.



Learning to shine light on a neuron is not the whole answer, though. In order for the method to work, the neurons have to be re-engineered so that they react to the light. That was made possible by the amazing discovery of a kind of protein that can be used to turn neurons on and off in response to light.

The exotic light-sensitive protein is not present in normal neurons, so scientists designed a way to insert it. That is accomplished through a type of gene engineering called "transfection" that employs "vectors" such as viruses to infect the target neuron, and, once there, to insert genetic material that will cause the neuron to manufacture the light-sensitive protein.

Put it all together, and you have that sci-fi-sounding technology: genetically-engineered neurons that you can turn on and off at will, inside the brain of a living and freely-moving animal.

It is the combined use of optics and genetics that give optogenetics its name, but it's not the "how" that makes optogenetics exciting, it is the "what." Scientists didn't really develop it to "take over" a creature's brain. They developed it, like fMRI, to learn about the brain, and how the brain works, in this case by studying the effect of stimulating specific types of neurons.

2012's space and science milestones

The technology is already beginning to pay off, and despite its recent invention, the word on the street is that a Nobel Prize isn't far off. In one application of optogenetics, scientists investigated how neurons that make dopamine, a neurotransmitter in the brain, may give rise to feelings of reward and pleasure. That work may help scientists understand the pleasure-related pathologies involved in clinical depression.

In another application, scientists selectively stimulated brain cells in animal models of Parkinson's disease, a disease that involves the disruption of information-processing in the brain. That research gave new insight into the circuitry involved in the disease, and the way that the therapies we currently prescribe for it operate. It has also suggested new directions for therapeutic intervention.

Schizophrenia is another disorder that involves information processing issues in the brain. The illusion of hearing voices, for example, may arise from the failure of an internal mechanism for notifying a person when his or her thoughts are "self-generated." Optogenetics has been employed to better understand a kind of brain activity called "gamma oscillations" that appear abnormal in schizophrenia -- and also in autism.

Today, we are a long way from the era when a single person working with an assistant or two can make a revolutionary technological breakthrough. It took, instead, decades of work in many fields, which came together, only very recently, to bring Crick's vision to fruition. But now that it's here, optogenetics is destined to change the way we treat mental illness, and eventually, even, the way we understand ourselves as human beings.

Follow us on Twitter @CNNOpinion

Join us on Facebook/CNNOpinion

The opinions expressed in this commentary are solely those of Leonard Mlodinow.

ADVERTISEMENT
Part of complete coverage on
July 10, 2014 -- Updated 1620 GMT (0020 HKT)
Frida Ghitis says a poll of 14 Muslim-majority nations show people are increasingly opposed to extremism.
July 10, 2014 -- Updated 1828 GMT (0228 HKT)
Ruben Navarrette says spending more on immigation enforcement isn't going to stop the flow of people seeking refuge in the U.S.
July 10, 2014 -- Updated 2048 GMT (0448 HKT)
Faisal Gill had top security clearance and worked for the Department of Homeland Security. That's why it was a complete shock to learn the NSA had him under surveillance.
July 10, 2014 -- Updated 1841 GMT (0241 HKT)
Kevin Sabet says the scientific verdict is that marijuana can be dangerous, and Colorado should be a warning to states contemplating legalizing pot.
July 9, 2014 -- Updated 2047 GMT (0447 HKT)
World War I ushered in an era of chemical weapons use that inflicted agonizing injury and death. Its lethal legacy lingers into conflicts today, Paul Schulte says
July 10, 2014 -- Updated 1137 GMT (1937 HKT)
Tom Foley and Ben Zimmer say Detroit's recent bankruptcy draws attention to a festering problem in America -- cities big and small are failing to keep up with change.
July 10, 2014 -- Updated 1201 GMT (2001 HKT)
Mel Robbins says many people think there's "something suspicious" about Leanna Harris. But there are other interpretations of her behavior
July 9, 2014 -- Updated 2006 GMT (0406 HKT)
Newt Gingrich warns that President Obama's border plan spends too much and doesn't do what is needed
July 9, 2014 -- Updated 1753 GMT (0153 HKT)
Amy Bass says Germany's rout of Brazil on its home turf was brutal, but in defeat the Brazilian fans' respect for the victors showed why soccer is called 'the beautiful game'
July 8, 2014 -- Updated 1754 GMT (0154 HKT)
Errol Lewis says if it really wants to woo black voters away from the Democrats, the GOP better get behind its black candidates
July 9, 2014 -- Updated 2107 GMT (0507 HKT)
Aaron Carroll explains how vaccines can prevent illnesses like measles, which are on the rise
July 9, 2014 -- Updated 0008 GMT (0808 HKT)
Aaron Miller says if you think the ongoing escalation between Israel and Hamas over Gaza will force a moment of truth, better think again
July 8, 2014 -- Updated 2241 GMT (0641 HKT)
Martin Luther King Jr. fought and died so blacks would no longer be viewed as inferior but rather enjoy the same inherent rights given to whites in America.
July 9, 2014 -- Updated 1147 GMT (1947 HKT)
Alex Castellanos says recent low approval ratings spell further trouble for the President
July 9, 2014 -- Updated 0349 GMT (1149 HKT)
Paul Begala says Boehner's plan to sue Obama may be a stunt for the tea party, or he may be hoping the Supreme Court's right wing will advance the GOP agenda that he could not
July 6, 2014 -- Updated 1659 GMT (0059 HKT)
The rapture is a bizarre teaching in fundamentalist circles, made up by a 19th-century theologian, says Jay Parini. It may have no biblical validity, but is a really entertaining plot device in new HBO series
July 7, 2014 -- Updated 1749 GMT (0149 HKT)
Ruben Navarrette: President Obama needs to send U.S. marshals to protect relocating immigrant kids.
July 8, 2014 -- Updated 1903 GMT (0303 HKT)
Norman Matloff says a secret wage theft pact between Google, Apple and others highlights ethics problems in Silicon Valley.
July 8, 2014 -- Updated 2237 GMT (0637 HKT)
The mother of murdered Palestinian teenager Mohammed Abu Khder cries as she meets Palestinian president Mahmoud Abbas in Ramallah, West Bank on July 7, 2014.
Naseem Tuffaha says the killing of Israeli teenagers has rightly brought the world's condemnation, but Palestinian victims like his cousin's slain son have been largely reduced to faceless, nameless statistics.
July 9, 2014 -- Updated 2028 GMT (0428 HKT)
Danny Cevallos says charging the dad in the hot car death case with felony murder, predicated on child neglect, was a smart strategic move.
July 8, 2014 -- Updated 1326 GMT (2126 HKT)
Van Jones says our nation is sitting on a goldmine of untapped talent. The tech companies need jobs, young Latinos and blacks need jobs -- so how about a training pipeline?
July 7, 2014 -- Updated 1309 GMT (2109 HKT)
A drug that holds hope in the battle against hepatitis C costs $1,000 per pill. We can't solve a public health crisis when drug makers charge such exorbitant prices, Karen Ignagni says.
July 7, 2014 -- Updated 1133 GMT (1933 HKT)
Julian Zelizer says our political environment is filled with investigations or accusations of another scandal; all have their roots in the scandal that brought down Richard Nixon
July 6, 2014 -- Updated 1814 GMT (0214 HKT)
Sally Kohn says Boehner's lawsuit threat is nonsense that wastes taxpayer money, distracts from GOP's failure to pass laws to help Americans
July 7, 2014 -- Updated 1526 GMT (2326 HKT)
Speaker John Boehner says President Obama has circumvented Congress with his executive actions and plans on filing suit against the President this month
ADVERTISEMENT