Chimps Driven to Distraction

We all know how hard it can be to hold out for a big reward rather than take a smaller reward right now. But while pigeons, rats, monkeys and chimps show the similar behavior when offered food treats, only chimps can learn to distract themselves to sustain their self-control.

In a session called “Worth Waiting For — The Evolutionary and Developmental Foundations of Self-Control,” Michael Beran, PhD, of Georgia State University, described experiments he has conducted with chimps, orangutans and rhesus and capuchin monkeys.78779344

Orangutans could learn to wait about a minute if it meant they’d get a larger food treat, Beran said. But “rhesus monkeys were terrible – they just never got good at this.” And capuchin monkeys also struggled – but they could exert some self-control under certain conditions.

Beran and his colleagues designed an experiment in which capuchin monkeys were presented with two pieces of banana on a turntable, one small that was close to the monkey and a larger one that was farther away. The monkeys could see both pieces and they were able to stick their hands out of the cage to take the food. The monkeys would initially impulsively grab the smaller, closer piece of banana but eventually they learned to wait for the turntable to spin around and present the bigger piece, Beran said — although some capuchins were better at the task than others.

89792548Chimps, on the other hand, could learn to wait almost as long as children. (Remember Walter Mischel’s marshmallow experiments in which preschoolers had to wait to get two marshmallows instead of one now?) Beran created an accumulation test where chimps would get more food treats if they could wait. The food was given to them through a delivery tube that went into their cages.

“All the chimpanzees learned quickly to wait,” he said, but some would touch or pick up the food (or the food delivery tube) but not eat, having learned that they would still get more as long as they didn’t eat anything. That led Beran to theorize that touching the food or tube might be a distraction that enabled them to wait longer. So he devised another experiment where some chimps were given toys to play with, some could not reach the food delivery tube and some were given no distractions and could reach the tube. The chimps with the toys could wait an additional 500 seconds to get the treats.

“I would make a pretty strong case that this is self-distracting,” he said.



Food for Thought: Too Sweet for their Own Good?

160493980Most of us, intentionally or not, have consumed foods and beverages flavored with artificial, or non-nutritive, sweeteners. They are widespread in processed foods, including soft drinks, candy, dairy products, baked goods and numerous other products. The words aspartame, sucralose or saccharin no longer look foreign or hard to pronounce. On the contrary, they are frequently used by millions worldwide, and many people are not even aware that their low-calorie (but delicious!) foods often contain one or more artificial sweeteners.

The idea is appealing at the very least – sweetness without the caloric impact (and guilt). Why drink a can of soda that has 130 calories when you can enjoy one that has none? This is one reason why using artificial sweeteners has been a strategy to combat the obesity epidemic. Similarly, non-nutritive sweeteners are an attractive option for those with diabetes, because unlike sugar, they do not raise blood glucose levels since they do not contain carbohydrates.

However, it turns out that the process is more complicated than it may seem. According to Susan E. Swithers, PhD, a psychologist from Purdue University, the consumption of artificial sweeteners might contribute to, rather than ameliorate, weight gain and exacerbate chronic diseases like diabetes, heart diseases and high blood pressure. She talked about this yesterday in her presentation.

“Although we’ve been led to believe that artificial sweeteners like saccharin, sucralose and aspartame will automatically lead to better health outcomes, long-term data from human cohort studies indicate that risks for chronic diseases is actually higher in people who are consumers of diet beverages compared to those who don’t use them,” said Swithers.

Based both on her as well as prior animal research, high-intensity sweeteners have been associated with increased food intake and weight gain. Interestingly, though, consumption of artificial sweeteners (as opposed to glucose) caused the most weight gain in animals fed “Westernized” diets high in fats and sugars.

With that said, the idea that non-caloric, high-intensity sweeteners may promote rather than prevent weight gain is not a new one. The premise behind it is that non-caloric sweeteners and fat substitutes disrupt taste-calorie associations that regulate eating and adiposity. In other words, people tend to calorically over-compensate for the zero-calorie beverages or low-calorie foods they consume. The result is too many calories, often from health-wise suboptimal sources, and weight gain.

Yet Swithers’ finding is an intriguing one. It suggests that some of us may be more prone to weight gain from non-nutritive sweetener use than others. And unfortunately, those who are at highest risk are also those who are most likely to choose them.

“We tend to think that the negative effects of artificial sweeteners on things like weight gain are due to cognitive distortions that lead people to overeat, but the animal work indicates that these products can interfere with much more fundamental learning processes that are typically happening in the background without us having to use cognitive resources,” she said. “And these data show that interfering with these basic processes can alter release of hormones that normally help us regulate not only our food intake, but our blood sugar as well, and that have protective effects on the cardiovascular system over the long run. So even if people could somehow compensate for the tendency to overeat, these physiological effects may still make them more vulnerable to chronic diseases.”

In light of these findings, what recommendations about artificial sweetener use should a doctor give to an obese patient in order to promote weight loss? Should his or her regular diet and gender be considered? While it may still be too early to translate and apply animal research findings to humans, as with most things in life, I would err on the side of caution. Even though artificial sweeteners have been on the market for several decades now, we still don’t know everything about the non-nutritive sweeteners. A regular chocolate chip cookie – if you really want it – and a brisk walk may therefore be your best bet when trying to prevent the excess pounds.

Have more thoughts on this topic? Reply below.

Nicole Avena, PhD studies appetite and addiction at the NY Obesity Research Center, at Columbia University. You can learn more about her work at She can also be found on Twitter and Facebook, or on her Psychology Today blog.

Got Conference Brain?

strong BrainHundreds of presentations, panels and symposiums were offered each day and as I attended a fairly full schedule of my own, I could not help but to reminisce about how similar this was to high school. Here we are “attending classes” for an hour or two at a time, having 10 minutes to get to our next “class” while trying to catch up with all of our friends and colleagues, and repeating until the end of the day. It can be difficult to absorb all of this important information and, if you are like me, you might experience “conference brain” – that slight feeling of being disoriented, enlightened, excited and exhausted.

From previous conference experiences, I’ve adapted a couple methods to help me stay present and excited throughout a long day:

  1. Pace Yourself – While there are so many great workshops and presentations to go to, don’t forget to schedule appropriate breaks. Allow and plan for time to digest a presentation, discuss it with colleagues, and take notes before moving on to the next session.
  2. Fresh Air – Air conditioning can feel nice, especially on a warm D.C. summer day. However, dark or dimly lit presentation or workshop rooms can bring a sense of sleepiness, especially if it is your fifth workshop of the day. Try to take some time to walk outside and get some sunlight, breathe some fresh air and take in the sites that D.C. has to offer.
  3. Acceptance and Non-Judgment – When I was a graduate student attending conferences, I always felt the need to attend every session every hour that I was at the conference to ensure that made the most of my time and money. The truth is, I cannot remember half of those sessions and that was likely attributed to attending with conference brain. Notice that if there is self-judgment — i.e., “I should go” — and try to practice self-care and self-compassion. You can allow this convention to be both educational and enjoyable.

If you have additional tips or tricks that you’d like to share on how to reduce conference brain, I’d love to hear about it in a comment or in a tweet with #APA2014.