Tag Archives: amygdala

L and R: Brain and Politics

Do you hear the people sing? Singing a song of angry men? It’s the music of the yellow vests who shut down subway stops on weekends.

As dedicated as I have been to eating Saturday brunch, the yellow vests (gilets jaunes to the French) have been just as dedicated to convening on Saturday afternoons to protest. The yellow vests are a French populist group mostly made up of members of the working and middle classes who express frustration about slipping standards of living. For the past few months since October 2018, the yellow vests have been showing up every weekend in major Paris locations to protest for lower fuel taxes, redistribution of wealth, an increase in minimum wage, and even the resignation of French President Macron (Diallo, 2018). I remember reading throughout the semester New York Times articles about these protests back when I was in America, and it all seemed very removed from where I was at the time. But now, there is no way to forget when every weekend I receive an email from our study abroad program center about the yellow vests’ path of protest for the weekend and have to track what popular tourist areas will be out of commission for the day. Indeed, Les Mis was not all that misleading. It seems that since the beheading of Queen “Let Them Eat Cake,” the French people have not been able to shake the love of a good revolution or protest from their society. But it is definitely not only the French that enjoy political demonstrations; from 1960s UC Berkeley students to my pink knitted hat compatriots, America has a its own unique history with political movements. I wanted to know – what is it about politics that seems so intrinsic and enticing that people are motivated to come out, rain or shine, to walk around and yell collectively??

major sites of closure yellow vest protests have caused

Part of the reason that being a part of a political movement can be so enthralling is the association with a political party that people flaunt. This gives members of the group a sense of belonging, which is a basic human need involving complex emotions of love, pride, and emotional excitement (Jasper, 2011). In America and many other nations, there is a divide between the liberal left and the conservative right. The ideological labels of “left” and “right” have been around since the time Christian symbolism associated right with “liking for or acceptance of social and religious hierarchies” and the left with “equalization of conditions through the challenge of God and prince.” This fundamental difference in political ideology has remained relatively intact throughout the centuries since then (Jost, 2014). While for many year scientists have assumed political orientation to be solely the result of upbringing and environmental factors, there have recently been studies identifying biological influences on individual’s political attitudes. This field of study falls under neuropolitics, or the study of how neuroscience and political science intersect (Schreiber, 2017).

In a 2011 study that tried to elucidate whether brain structure differences could be linked to political associations, the brain region of the anterior cingulate cortex (ACC) was studied. The ACC has connections to both the “emotional” limbic system” and “cognitive” prefrontal cortex of the brain and is involved with conflict monitoring – the task of detecting conflicts in information processing and then signaling when increased cognitive control must be recruited (Yeung, 2013). The 90 young adult test subjects were first asked to self-report their political attitude on a five-point scale ranging from “very liberal” to “very conservative.” Although a simple scale, this self-reported result has been shown to accurately predict voting behavior. Magnetic resonance imaging (MRI) scans that show detailed images of the brain were then taken of each subject to assess differences in volume of ACC. Results of their scans after controlling for age and gender variables showed that increased gray matter volume in the ACC was significantly associated with liberalism. This hinted that individuals with larger ACC may tolerate uncertainty and conflicts better and allow them to hold more liberal views. The same study also looked at the amygdala, which is involved in processing emotional responses such as fear and aggression, to look for links between gray matter volume of amygdala and political ideology. By evaluating amygdala volume and political attitudes, researchers saw there was an increased amygdala volume associated with conservatism, suggesting that conservatives respond to threatening situations with more aggression and have a heightened sensitivity to fear (Kanai et al., 2011).

a. Results showing ACC volume in comparison with political ideology
b. Results showing amygdala volume in comparison with political ideology

Of course, the question of “which came first, the chicken or the egg?” also applies here: are people more inclined to lean a certain political direction based on biologically predetermined brain differences or do people’s political ideology lead to slight but significant changes in brain structure? I would have been interested to hear if the researchers had any thoughts on this or had long-term data comparing subjects to look for correlations that may have helped answer this question. The researchers also mention a stipulation to their results that abstract reasoning and thinking often requires widespread brain regions and cannot be traced back to one specific brain region. Additionally, a recent review of neuropolitics warns people of the “pathologisation of politics” which essentially chalks up political problems into biological deviations (Altermark & Nyberg, 2018). I think this is especially pertinent as weaponizing neuroscience in order to reduce those you do not agree with is not the purpose of studying the brain. Overall, no matter left or right, remember the brain functions best with both working together!

 

Bibliography

Altermark, N., Nyberg, L. (2018) Neuro-Problems: Knowing Politics Through the Brain. Culture Unbound, 10, 31-48.

Diallo, R. (2018, December 19). Why are the ‘yellow vests’ protesting in France? Al Jazeera, Retrieved from https://www.aljazeera.com/indepth/opinion/yellow-vests-protesting- france-181206083636240.html

Jasper, J.M. (2011) Emotions and Social Movements: Twenty Years of Theory and Research. Annual Review of Sociology, 37, 285-303.

Jost, J.T., Nam, H.H., Amodio, D.M. & Van Bavel, J.J. (2014) Political Neuroscience: The Beginning of a Beautiful Friendship. Political Psychology, 35, 3-42.

Kanai, R., Feilden, T., Firth, C. & Rees, G. (2011) Political orientations are correlated with brain structure in young adults. Curr Biol, 21, 677-680.

Schreiber, D. (2017) Neuropolitics: Twenty years later. Politics and the Life Sciences, 36, 114- 131, 118.

Yeung, N. (2013). Conflict monitoring and cognitive control. In: Oxford Handbook of Cognitive Neuroscience (Ochsner, K. and Kosslyn, S., eds), Oxford University Press (in press).

Image 1: https://www.usnews.com/news/world/articles/2019-02-09/more-violence-in-paris- as-yellow-vests-keep-marching

Image 2: https://www.bbc.co.uk/news/world-europe-46499996 Image 3: Kanai et al., 2011

my bubble has been popped

It’s 9 AM – rush hour on the metro. The platform is packed and the people of France know very little regarding personal space. As the offensive warning of door closure sounds, it’s as if the lid to a tightly packed sardine tin is being jammed shut. Looking around, the only person that might give you a smile is the baby in the stroller, the rest adorn deadpan expressions, chatter is low, and the screech of the metro rings through my ears. As a man stands on my foot and the hair of the woman in front of me grazes across my lips, the words “excusez-moi” or “pardon” fail to be uttered. It is a way of life and, honestly, I was probably in the way.

A typical platform of the RER after a full ride.

This unapologetic lack of personal space can be attributed to the amygdala based on an fMRI study done by Kennedy et al. (2009). A bilateral lesion of the amygdala resulted in very little regard to personal space. The amygdala plays a role in strong emotional responses and in this case, in regards to the proximity to others. In this experiment, a patient with bilateral lesions of the amygdala felt comfortable with an individual at a significantly closer distance than a healthy individual reported. Given my experience on the metro, I predict that my amygdala activity was quite high.

In another study done by Graziano and Cooke (2006), it was found that the ventral intraparietal area (VIP) and a polysensory zone in the precentral gyrus (PZ) both respond to objects that are touching or looming toward the body’s surface. These areas give rise to the ‘personal space bubble’ that most of us cherish in the United States. In fact, stimulation of these areas can result in defensive behavior such as avoidance or blocking maneuvers (Graziano and Cooke, 2006). My New Englander mentality reports that a quick elbow nudge or jerk of my foot from beneath my fellow passenger’s may send the message of my discontent but, apparently not.

In a different context, in a study of Borderline Personality Disorder patients, amygdala and parietal cortex activation of patients was lower than baseline when in close proximity to others (Schienle et al., 2015). Invasion into the subject’s ‘personal bubble’ was simulated by zooming in on pictures of facial expressions. Borderline Personality Disorder patients only showed increased activation in these areas if the facial expression showed disgust. Otherwise, there was very little concern with a lack of personal space in comparison to the control patients.

An average metro ride.

Perhaps the French have evolved to have lower activation in the amygdala and parietal cortex? Just food for thought. Either way, I know that I’m certainly not used to it and for about 35 minutes on the metro (and many other places) I feel like my bubble has been popped. Everything and everyone is about 5 inches closer to my body than it should be…but maybe my amygdala and parietal cortex will adapt as the weeks go on!

 

 

Graziano MSA, Cooke DF (2006) Parieto-frontal interactions, personal space, and defensive behavior. Neuropsychologia 44: 845-859. doi: 10.1016/j.neuropsychologia.2005.09.009

Kennedy DP, Gläscher J, Tyszka JM, Adolphs R (2009) Personal space regulation by the human amygdala. Nature Neuroscience 12: 1226-1227. doi: 10.1038/nn.2381

Schienle A, Wabnegger A, Schöngassner F, Leutgeb L (2015) Effects of personal space intrusion in affective contexts: an fMRI investigation with women suffering from borderline personality disorder. Social Cognitive and Affective Neuroscience 10(10): 1424–1428. doi: 10.1093/scan/nsv034

 

Poisoning Pigeons in the Park

We’ve now been in Paris for close to three weeks. It’s a wonderful city, and I’ve enjoyed so many terrific experiences since we arrived: long, sunny walks along the Seine from the Louvre Museum to the Eiffel Tower, terrific concerts by countless street musicians, and many delicious French crepes and baguettes! However, there’s one part of Paris that is slowly pecking away at my enjoyment of the city – Pigeons. 

Paris isn’t quite as famous for its pigeons as other large cities like New York and London, but their presence is certainly noticeable – especially if you attempt, as I did, to eat a fresh baguette under the statue of Charlemagne at Notre Dame, an area where the pigeon density rivals that of the tourists. As soon my first breadcrumb dropped, I was surrounded and bombarded by more birds than I could count. This happened again at Tuileries Garden, and yet another time on the Cite Universitaire campus.

Even when I’m not eating baguettes the pigeons seek me out. While relaxing in a small urban park near the Bastille I was lucky enough to receive a pigeon “deposit” on my pant’s leg, followed by another on my chest and a third that landed on my shoulder, narrowly missing my right ear. I can see one such gift being an accident, but three in a row makes me think that these pigeons might have a vendetta against me for the bird research I do back at Emory.

It turns out that I’m not the only one who’s annoyed with Paris’s bird problem. For many years the city has pigeon-proofed historical buildings by placing spikes on all the ledges where the birds might land. Additionally, in 2008 Paris officials set out to curb the pigeon population by building nesting-lofts throughout the city and then sterilizing the eggs while the birds were out feeding (bloomberg). Given my recent experiences, these attempts don’t appear to be working and so I looked into another possible method of population control – feeding the birds poison-laced food.

I was curious about how effective poisoning would be. Do the birds learn to avoid dangerous food? And if so, how quickly does this avoidance behavior develop, especially if that food had a distinct taste or smell associated with it?

How quickly do pigeons learn to avoid poison?

A map of the places I've had run-in with pigeons


In 1999 a study published in the Archives of Environmental Contamination and Toxicology looked exactly at how quickly pigeons learn to avoid poisonous-food and the effect of hunger on the amount of toxic food they ingested (Pascual et al., 1999).

The study used four groups of eight pigeons. Two of these groups were given as much food as they wanted (ad libitum) for the 6 days leading up to testing while the other two groups were deprived of food. The researchers did two experiments. First they offered seeds laced with the sulfurous-smelling toxin fonofos to one of the ad libitum groups and one of the deprived groups for 6 straight hours. The birds were videotaped throughout the test, and eating behavior was measured by the amount of food eaten as well as the rate at which it was consumed. The second experiment, using the remaining two bird groups, was very similar but the food was offered first for 2 hours followed by a half-hour break, and then for an additional four hours. While not much different then the first experiment, this test showed whether the birds were able to remember that the food was dangerous when exposed to it a second time.

On average, it only took the birds 6 minutes to learn to avoid the food and all of the pigeons from experiment two still avoided the food after a half-hour break. Five of the birds from the food-deprived group did die and the authors attributed this to the fact that these birds ate huge amounts of food in the first six minutes. This is interesting because it suggests that the ability to develop avoidance behaviors is dependent on time, not on the amount of food eaten. Additionally, the video recordings showed reactions (head shaking, food-spitting, vomiting) during the first six minutes, which confirmed that the food was unpleasant to the birds. Given the size of the Parisian pigeons that have harassed me so far, I doubt any of them are food deprived, so unfortunately poisons (or at least poisons that have odor or taste like fonofos) would not be effective.

While this article clearly documented the development of avoidance behaviors and specifically showed that internal state (such as hungry/not hungry) did not affect the rate at which these behaviors we were created, it did not discuss how these behaviors are mediated in the brain.

How is avoidance mediated in the brain?

A pigeon posing in front of the Eiffel Tower. A perfect summary of my experiences so far in France.

 

 

Most research in avoidance behavior concentrates on the role of a small almond-shaped region in the bottom-middle of the brain called the amygdala, which is thought to mediate avoidance behavior development (Davis, 1992). How exactly it does this is still being debated but the majority of articles suggest that the amygdala helps consolidate a memory associated with an unpleasant experience like eating food that makes you feel sick (Smith et al., 2001). More specifically, some research has shown that it plays a role in the initial acquisition of the memory (Wiliskey et al., 2005). Even though these studies were not done in pigeons, we can use can use them to predict what might have occurred in the pigeon experiment. When the pigeons first ate the fonofos food and experienced the unpleasant side effects, it’s possible that their amygdalae were activated and that a connection between the food and the effects was formed. However, this connection in the brain probably was not strong enough to cause avoidance after just one exposure to the food, so it took multiple exposures over the course of six minutes. Even though the food-deprived pigeons ate more, it’s possible that they didn’t avoid the food any faster than the ad libitum group because their hunger took priority and inhibited the avoidance behaviors from forming (Gilette et al., 1999).

Unless the Parisian pigeons have faulty amygdalae, which I highly doubt, I will unfortunately have to come up with another way to control their population. Perhaps, a poison that doesn’t have any smell or immediate unpleasant effects associated with it? Or maybe the best option is just to take all of my baguette eating indoors. Regardless, it does not appear that I will be poisoning Parisian pigeons anytime in the near future. Now that you’ve finished the post I recommend that you click on the following link and enjoy a 3 minute tune by 1960s comedian Tom Leher, it applies nicely.

http://www.youtube.com/watch?v=yhuMLpdnOjY

 

– Camden MacDowell

UPDATE: I GOT EVEN WITH THE PIGEONS!

mmm... tasty pigeon lunch! Literally the taste of revenge!

 

Works cited:

Davis M. (1992) The role of the amygdala in fear and anxiety. Annual Review Neursci 15:353-375

Gillete R., Hatcher N., Huang R., Moroz L. (1999). Cost-benefit analysis potential in feeding behavior of a predatory snail by integration of hunger, taste, and pain. PNAS 97: 3585-3590

Pascual J., Fryday S., Hart A. (1999) Effects of Food Restriction on Food Avoidance and Risk of Acute Poisoning of Captive Feral Pigeons from Fonofos-Treated Seeds. Arch. Environ. Contam. Toxicol. 37: 115-124

Smith DM., Freeman JH., Gabriel M., Monteverde J., Schwartz E. (2001) Lesions in the central nucleus of the amygdala: discriminative avoidance learning, discriminative approach learning, and cingulothalamic training-induced neuronal activity. Neurobiol Learn Mem 76: 403-25

Wilensky A., LeDoux J., Schafe G. (2005) Amygdala Modulates Memory Consolidation of Fear-Motivated Inhibitory Avoidance Learning But Not Classical Fear Conditioning. The Journal of Neurosci 20: 7059-7066