Brains Applied's video: Why Do We Get Hangry

"You're Not You When You're Hungry!" Do you recognize it? It's the famous tagline of a worldwide Snickers campaign. A campaign that has been published in 80 countries, featuring celebrities such as Rowan Atkinson, Joe Pesci, Betty White, and many others. In this article, I'm not going to discuss the specifics of the campaign. Many great Medium writes have done this before, as you can see here, here and here. I'm going to discuss hangriness. As you might (or might not) remember, hangriness is an often recurring theme in the Snickers commercials. In the same way that junkies can't live without their drugs, hunger supposedly turns you into Danny Trejo or Mr. Bean. Obviously, the sudden transformation into Mr. Bean is over the top. But is hangriness a real emotion? Or is it just an invention by Snickers to advertise their brand? In 2014, researchers let 107 married couples measure their glucose levels before going to bed over a period of 21 days. At the same time, the participants were supposed to stuck 0 to 51 pins into a voodoo doll that represented their spouse, depending on how angry they were at them. Upon returning the equipment to the lab, the couples were separated as each of them had to play a game against their spouse. (They weren't told that every participant was playing against the computer, to avoid the game from escalating too much.) The participants had to press a button as fast as possible when a target on the computer screen turned red. The winner of each round was allowed to pick a sound, its volume (60–105 dB) and its duration (0.5–5 seconds) to blast through the headphones of their losing "partner". Examples of such sounds are an ambulance siren or the eerie sound of fingernails scratching a blackboard. Both experiments showed that low glucose levels often resulted in more acts of "marital aggression". For quite some time, researchers reasoned that when your glucose level decreases, so does your level of self-control which results in hangriness. As several studies eventually contradicted this hypothesis, researchers came up with a different theory: being angry is just very similar to being hungry. The similarity starts at the neurological aspect of hangriness: emotions and hunger both tend to increase the neural activity in your anterior cingulate cortex, insula, and amygdala. (If you didn't know: these are brain regions.) But there's more: when your glucose level drops, your brain and tummy release Ghrelin (a.k.a. The Hunger Hormone). Ghrelin, in its turn, triggers the release of stress hormones such as cortisol and epinephrine (pronounce: e-puh-NEH-fruhn). On top of that, the Ghrelin will trigger the neuropeptide-Y neurons in the brain. There's a lot that I can say about neuropeptide-Y, but you should just remember that it regulates both food intake and aggression. Need I say more? Now the final question remains: Is there an evolutionary advantage to hangriness? There sure is! When you're living in a group or a herd of people (or animals) and food is scarce, being more aggressive can make the difference between eating or starving. So whenever the beast in you gets hangry:, don't worry you're just trying to survive. Go and try to find the nearest cookie jar! Don't forget to like and subscribe! Music by Bensound.com References: Bushman, B. J., DeWall, C. N., Pond, R. S., & Hanus, M. D. (2014). Low glucose relates to greater aggression in married couples. Proceedings of the National Academy of Sciences of the United States of America, 111(17), 6254–6257. Fattorini, N., Brunetti, C., Baruzzi, C., Macchi, E., Pagliarella, M. C., Pallari, N., … Ferretti, F. (2018). Being "hangry": Food depletion and its cascading effects on social behaviour. Biological Journal of the Linnean Society, 125(3), 640–656. Gaines Lewis, J. (2016). Why Do We Get "Hangry"? Retrieved September 6, 2020, from https://www.psychologytoday.com/intl/blog/brain-babble/201607/why-do-we-get-hangry Karl, T., Lin, S., Schwarzer, C., Sainsbury, A., Couzens, M., Wittmann, W., … Herzog, H. (2004). Y1 receptors regulate aggressive behavior by modulating serotonin pathways. Proceedings of the National Academy of Sciences of the United States of America, 101(34), 12742–12747.  Kohno, D., Gao, H. Z., Muroya, S., Kikuyama, S., & Yada, T. (2003). Ghrelin directly interacts with neuropeptide-Y-containing neurons in the rat arcuate nucleus: Ca2+ signaling via protein kinase A and N-type channel-dependent mechanisms and cross-talk with leptin and orexin. Diabetes, 52(4), 948–956.  Kouchaki, M., & Smith, I. H. (2014). The Morning Morality Effect: The Influence of Time of Day on Unethical Behavior. Psychological Science, 25(1), 95–102. MacCormack, J. K., & Lindquist, K. A. (2019). Feeling Hangry? When Hunger Is Conceptualized as Emotion Empirical evidence demonstrates that emotions impact every aspect of our waking lives, from visual perception to decision-making and interpersonal processes (e.g. Emotion, 19(2), 301–319.