"Brain imaging is not a very good way to test subtle distinctions [in the brain]...it's like trying to find out something about New York City by studying New York State," says NYU neuroscientist Joseph LeDoux, one of the pioneers of neuroscientific animal research back in the 1970s. "Animal research is so important because we can go in and study individual cells and individual synapses on those cells," he says. But can we take the information we learn about the brains of rats and apply that knowledge to the endlessly complex human brain?
In his second Big Think interview, LeDoux told us that, yes, we can learn much from studying rats' brains, even about things like emotion, which we often attribute solely to humans. "Through the history of psychology, there's been a struggle between what can we learn about psychological states in humans and animals, what can we learn about psychological states by studying conscious states in people and unconscious states," LeDoux explains. In the 1930s and '40s, the behaviorists threw out the idea of consciousness because it is a subjective pehnomenon that cannot be measured. Then the cognitive revolution of the '50s and '60s brought the mind back to psychology, "but it didn't bring back the mind that the behaviorists got rid of," says LeDoux. "When I got interested in emotion in the '70s, emotion was still being thought of in terms of subjective conscious experiences, whereas other aspects of psychology, like perception and memory were thought of as information processing functions." LeDoux revolutionized the study of emotion, especially of fear, by thinking about it in terms of observable behavior. "All animals have to be able to detect danger and respond to danger in order to stay alive, including humans." And because this is such a basic evolutionary adaptation, it functions quite similarly between animals and humans.
The hub of all emotional processing in both human and animal brains is the amygdala, says LeDoux, also the frontman of a rock group called The Amygdaloids. He has spent his career studying this almond-shaped structure, and he gave us a five minute primer on everything we should know about it. "What the amygdala is doing is forming associations between random or neutral external stimuli and the kinds of reinforcing events that will stamp in those experiences in a stronger way," he says. "So its creating what's called Pavlovian associations: you know, stimulus one plus stimulus two; if one of those is a biologically significant stimulus, then the other one will acquire some kind of biological significance itself, whether it’s positive or negative."
LeDoux also talked to us about some of the groundbreaking research to have come out of his his lab in recent years. One discovery dealt with a process called "reconsolidation" of memory. "When you retrieve a memory it becomes unstable and new information can be incorporated into the memory at that point," he says. "It also means that when the memory is unstable, its restabilization process can be blocked. And if you block that, the memory is weakened or dampened. So that's how we've been using reconsolidation to help people with traumatic memories to try and dampen their memories of those traumatic situations."
LeDoux also told us about his current studies of rats with extreme fear. "We can compare animals that are really afraid and those that are not afraid and look in their brains and see if there area any, for example, structural differences in the amygdala."
To create wiser adults, add empathy to the school curriculum.
- Stories are at the heart of learning, writes Cleary Vaughan-Lee, Executive Director for the Global Oneness Project. They have always challenged us to think beyond ourselves, expanding our experience and revealing deep truths.
- Vaughan-Lee explains 6 ways that storytelling can foster empathy and deliver powerful learning experiences.
- Global Oneness Project is a free library of stories—containing short documentaries, photo essays, and essays—that each contain a companion lesson plan and learning activities for students so they can expand their experience of the world.
Philosophers like to present their works as if everything before it was wrong. Sometimes, they even say they have ended the need for more philosophy. So, what happens when somebody realizes they were mistaken?
Sometimes philosophers are wrong and admitting that you could be wrong is a big part of being a real philosopher. While most philosophers make minor adjustments to their arguments to correct for mistakes, others make large shifts in their thinking. Here, we have four philosophers who went back on what they said earlier in often radical ways.
Astrophysicist Michelle Thaller talks ISS and why NICER is so important.
- Being outside of Earth's atmosphere while also being able to look down on the planet is both a challenge and a unique benefit for astronauts conducting important and innovative experiments aboard the International Space Station.
- NASA astrophysicist Michelle Thaller explains why one such project, known as NICER (Neutron star Interior Composition Explorer), is "one of the most amazing discoveries of the last year."
- Researchers used x-ray light data from NICER to map the surface of neutrons (the spinning remnants of dead stars 10-50 times the mass of our sun). Thaller explains how this data can be used to create a clock more accurate than any on Earth, as well as a GPS device that can be used anywhere in the galaxy.
Just before I turned 60, I discovered that sharing my story by drawing could be an effective way to both alleviate my symptoms and combat that stigma.
I've lived much of my life with anxiety and depression, including the negative feelings – shame and self-doubt – that seduced me into believing the stigma around mental illness: that people knew I wasn't good enough; that they would avoid me because I was different or unstable; and that I had to find a way to make them like me.
A joint study by two England universities explores the link between sex and cognitive function with some surprising differences in male and female outcomes in old age.