Dana Foundation Blog

Rethinking Emotion in the Lab

As I started reading Dana Alliance member Joseph LeDoux’s perspective article in the latest issue of Neuron, I had one picture of what the purring cat on my lap was feeling. After finishing the article, I had quite another. What if instead of thinking about whether animals have feelings similar to ours we think about what we have that goes beyond the “survival circuits and functions” seen in animals?

LeDoux, who wrote The Emotional Brain in 1998, has studied the topic for decades; he described his new perspective, a synthesis or rethinking of the field, at the annual meeting of the American Association for the Advancement of Science (AAAS). “Feelings are important, but I think they need to be studied in humans,” not animals, he said.

“Both psychotherapy and drug therapy for psychological issues could be improved by understanding emotions,” but the problem is, we don’t agree on how to define emotion itself. We often use the terms for feelings and emotion interchangeably (emotional pain v. measurable physical pain, for example), and “whatever problems might arise from using ‘feeling’ words to study human emotion, they are greatly compounded by using these words in animal research.”

Should we be looking for happiness, sadness, or love in the animal brain? No, he said. Instead, we should look for “conserved survival circuits”: systems the brain uses for defense, to manage energy and nutrition, to balance fluids and body temperature, and to procreate. "You're not going to find a joy or pleasure circuit of the brain,” for example, he said. "Pleasure is not a function of any one of these systems, but an integrated result of them."

Cleo is feeling...sleepy?

In the Neuron paper, 14 pages of clear, thorough text with another almost 8 pages of references, LeDoux sets his thinking out step-by-step. His main examples are of defense and reactions to fear; that has been the focus of his decades of research. Table 1 (page 661) suggests the many roles so-called emotional stimuli could play in circuits: “triggers” that activate them, “incentives” that could modify behavior, and “reinforcers” that support learning and memory. I also found Figure 2 useful, illustrating how a conditioned stimulus could travel a survival circuit to lead to innate behavior and perhaps through more paths to lead to learned, goal-directed actions.

LeDoux writes: “Consciousness and feelings are topics that are best studied in humans. Research on the neural basis of feelings in humans is in its infancy. We will never know what an animal feels. But if we can find neural correlates of conscious feelings in humans (and distinguish them from correlates of unconscious emotional computations in survival circuits), and show that similar correlates exists in homologous brain regions in animals, then some basis for speculating about animal feelings and their nature would exist.”

I can know that Cleo’s purring is a direct result of my petting her, but, I must remind myself, what she is feeling remains a mystery.

-- Nicky Penttila

The Importance of Sleep

Sleep is something I look forward to most of the time—it’s a great feeling to put my head on the pillow knowing how rejuvenated I’ll feel once I wake up. An article published earlier this week on The Huffington Post talks about how long we can go without sleep and some of the effects of neglecting sleep. According to the article, studies have shown that a lack of sleep affects behavior.

The article notes a 17-year-old who, in 1964, went 11 days without sleep, the longest recorded sleep drought for a human. The boy experienced memory problems, paranoia, and hallucinations. I can relate—just last night I stayed up nearly three hours past my normal bed time and am left with a headache and constant thoughts about getting back under the covers.

Research shows that the proper amount of sleep depends on your gender, age, and what’s happening in your brain. Babies and the elderly tend to sleep more, and new research suggests teenagers could use between nine and 11 hours of rest each night. The recommended amount for adults—eight hours—usually keeps me feeling refreshed.

The necessary amount of sleep differs for different people, but it is important that you fulfill your sleep requirement on a regular basis. Not doing so can lead to daytime sleepiness, which can affect your memory and ability to perform various functions. Since I didn’t get enough sleep last night, I’ll be extra careful to get to bed early tonight. Sleep well!

--Blayne Jeffries

Brain Oddities:The Weirdness of Sleep

During my freshman year of college, I took a supremely boring class called La Belle Epoque. In fact, it was so dull that I almost always nodded off during the lectures. Unfortunately, while drifting to sleep, I often experienced that unpleasant full-body convulsion that jerks you awake in the most embarrassing way possible. Good thing it was a 200-person lecture.

It turns out that this phenomenon has a name, and it is not, as I usually call it, “that awkward sleep twitch thing.” It’s actually known as hypnic myoclonia or a hypnic jerk, and is often preceded by a sensation of falling. (In my case, I usually dream of tripping—I guess the brain likes to pull from real life experience.) The majority of the population experiences this, although it is more commonly reported in those with irregular sleep schedules.

Like many brain-related conditions, the exact cause of hypnic myoclonia is unknown. In fact, the only thing we know for certain is that it’s super annoying. For now, the popular theory among sleep scientists is that as we drift off to sleep, our brain misinterprets our slackening muscles as falling and forces us to react.

Even more puzzling than hypnic myoclonia is periodic limb movement disorder (PLMD), previously known as nocturnal myoclonus. People with this condition suffer from excessive daytime sleepiness and have trouble falling asleep at night. When they do fall asleep, they display involuntary limb movements at bizarrely precise intervals, usually between 20 and 40 seconds. These intervals are so precise that you can extrapolate out five minutes and predict perfectly when they will twitch. Like hypnic myoclonia, the cause of PLMD is unknown, but it is related to stress, snoring, sleep apnea, and narcolepsy.

And finally, speaking of uncontrollable sleep movements, let’s discuss sleepwalking. I have only seen someone sleepwalk once in my life, and I will never forget it. What began as a high school, basketball-team-bonding, hair-brushing, boy-discussing sleepover eventually took a turn for the creepy. We were all awoken to one of our teammates walking around the dark house saying, “Mom, don’t leave me! I’m cold!” over and over in a strange voice. It was all very Exorcist.

The specific cause of sleepwalking is unknown, but we do know that it generally occurs during non-REM (NREM) sleep. Brain-wise, sleep is divided into REM sleep, during which we sometimes experience vivid dreams, and four stages of NREM sleep, distinguishable by their EEG rhythms. During REM sleep, the brain stem systems responsible for sleep processes actively inhibit spinal motor neurons, essentially leaving us paralyzed. The inhibition keeps us from acting out our dreams, thus protecting ourselves and others. During NREM, the inhibition stops and we are no longer paralyzed. However, with the exception of the occasional position shift, the brain does not usually send movement signals to the body during NREM.

I hope, for the sake of those who suffer from these sleep disorders (and of course, future generations of basketball-playing high school girls), sleep scientists can develop effective therapies and treatments. In the meantime, maybe we should just follow the example of bottlenose dolphins and put only one brain hemisphere to sleep at a time—it would certainly give a whole different meaning to being half-asleep.

--Caitlin Schneider

Sources:

American Academy of Sleep Medicine

Bear, M.F, Connors, B.W., Paradiso, M.A. (2006). Neuroscience: Exploring the Brain (3^rd edition). Lippincott Williams & Wilkins.

The neuroscience of murder

There is a killer lurking in the human brain. When the part of the brain that controls emotions and impulses is not suppressed, the killer within can wreak havoc on society. On March 16, I attended a discussion called “The Murderous Mind” with thriller writer Scott Turow and neuroscientist Michael Gazzaniga at the Rubin Museum of Art in New York. The event is part of the museum’s Brainwave series, now in its fourth year.

Many of us have had moments of rage where we’ve thought about killing someone. I’ve heard people say, I’m so mad, I could kill him (or her), but to my knowledge, they’ve never acted upon the thought. According to Gazzaniga, all people have a killer instinct that we keep controlled. “Everyone is capable of killing if triggered,” said Gazzaniga, who is a member of the Dana Alliance for Brain Initiatives and one of the world’s top cognitive neuroscientists. “The question is, can we overcome the trigger or impulse to do this?”

Gazzaniga differentiates between crimes of passion and premeditated crimes. “There are rage systems in the brain where the planning goes on, and when triggered, rage happens.” An example of this is when someone lashes out after being provoked. A person who is intent on committing a crime will plan out the act they want to commit, and carry it out whether they have been provoked or not.

Turow, a former prosecutor, defense attorney, and author of Presumed Innocent and other novels, has worked on cases with average citizens who seem to be nice people, but when wronged they immediately want retribution. “Victims were led to believe that retribution would make them feel restored,” said Turow. This is a way of thinking that tells us that since we were victimized and felt pain, someone else needs to feel pain as well. Turow also said that fictional police and crime shows make people believe retribution should be handled a certain way, instead of victims sitting down and thinking for themselves about how they would like to seek justice. In one case, Turow said, the criminal apologized to the family before being sentenced to life, and although it didn’t change what happened, his acknowledgement and act of compassion made the family members feel differently.

Gazzaniga said compassion can be measured on a scale of 1 to 10, with most of us being a four or five on average. “If you look at compassion,” said Gazzaniga, “and you look at the systems in the brain that process this, there’s a distribution [of brain chemicals] that goes into this.” Depending on the distribution, some people are able to express more or less compassion than others.

Sometimes thoughts and impulses go against the norm of society, but it’s up to us to control these feelings…unless we want our inner killer to break free.

--Blayne Jeffries

Lady Gaga not only one misinterpreting ideal "poker face"

I recently spent a night in Atlantic City with some friends to celebrate my birthday. As far as I knew, my brain was simply trying to decide between red or black, hit or stay, keep playing or walk away. Little did I know this was only a fraction of the activity going on in my head.

Two recent studies have delved into the psychology of gambling. The results of one of the studies are in line with my casino visits. The other, however, clashes a bit with my experience. I’ll start with the study that I found to be more congruent with my opinions.

Spanish psychologist Josep Marco-Pallares paired partners to play a very simple computer gambling game. Only one participant was doing the actual wagering, while the other either (1) had money on the same outcome as the gambler, (2) had money on the opposite outcome, or (3) was a neutral observer.

As expected, the brain responses of the active gamblers were distinct for wins and losses. The researchers were interested in the partner’s brain activity, though, and in the first two scenarios those responses were as expected: in the first, it mirrored the gambler’s; in the second, it was the opposite.

However, even when the gambling partner had no stake in the outcome, the brain responses of the two were the same when the gambler lost money. In other words, the observer reacted as if he/she had lost money as well. Interestingly, this similarity of responses was not evident when the gambler won.

I have certainly noticed this behavior in the casino, even if I could only go by outward reactions as opposed to brain scans. Last weekend, my friends and I huddled around another friend who was playing blackjack. I was certainly happy when he won, and congratulated him for a good hand. But I didn’t truly feel all that happy for him. I guess I was just happy he didn’t lose.

When he lost a hand, though—which, unfortunately, happened far more frequently—my empathy was definitely authentic. In fact, at times it seemed like I was more upset than he was over a losing hand (perhaps because I’m a more conservative gambler than he is).

Later in the night we played Pai Gow poker, and the results of Marco-Pallares’ study were happening before my eyes. With just one seat open at the table, I was the only one who sat down. However, two of my friends and I pooled our money to buy some chips. When my hand won, we split the profits three ways. Likewise, we all took a financial hit when we lost. It was clear we were all experiencing the same emotions—the joys of winning and the devastation of defeat.

After about an hour of playing, our other two friends joined us at the table. They stood with the two friends who were betting with me, but they simply observed. When I revealed a weak hand, all four shook their heads in disappointment. But when I had a monster hand, only my two fellow bettors seemed to show excitement.

The second study, conducted by Wellesley College psychologist Erik Schlicht, deals with how our opponents’ facial expressions influence the way we bet in poker. Participants were pitted against a computer opponent displaying a variety of facial expressions (as represented on the screen by a photo of a human). By giving participants similar hands and making them wager the same amount, researchers were able to isolate distinct facial expressions to record their effect.

They discovered that a trustworthy face gave players the most difficulties. When facing a computer opponent with such an honest countenance, players made more mistakes and were more likely to fold (the thought being, if someone looks trustworthy and bets, that person must have a good hand). The neutral “poker face,” the researchers found, did not make much of a difference.

Although poker was at the heart of the study, the implications don’t apply to actual poker. In the study’s FAQ section written by Schlicht, he admits that this experiment doesn’t carry over to casino poker. “I purposefully ‘strip away’ many of the factors that contribute to decisions in a ‘real’ poker game,” he writes.

At the same time, he also notes that “research is important as it allows for implicit (unconscious) effects to be uncovered, whereas poker [players] who are exclusively relying on experience need to be consciously aware of effects in order [to realize they exist].” This brings up the possibility that I’m simply not always aware of why I’m betting/folding at the poker table.

Either way, both studies have implications beyond a simple wager at a casino, according to the Scientific American article. The first can help learn more about gambling addictions—recovering addicts could relapse simply by observing others play—while the study on faces could aid in our understanding of how we assess certain people/situations, not just at the poker table but in the real world.

--Andrew Kahn