Sunday, February 10, 2013

Stephen T Asma - Rethinking the Emotional Life of Mammals

This cool article on how we tend to anthropomorphize the emotional states of animals, and the reality that animals, especially mammals (lower mammals all have a limbic system, which is the brain center for processing emotions), do have complex emotional lives.

The article gets into the work of neuroscientist Jaak Panksepp, one of the founders of affective neuroscience - the study of how emotions are constructed by the brain. His work is Nobel worthy - see The Archaeology of Mind: Neuroevolutionary Origins of Human Emotions.

An example is given below of Panksepp administering an electric shock directly into the hypothalamus of a cat. The cat responded by lunging at his head, "a hissing spitting tangle of fangs and claws." When the shock was turned off, the cat was its normal, peaceful self. Panksepp labels that response rage - and when human brains are stimulated in the same area, the word they use is rage.

However, it is in this last sentence that the question arises: How much do animals understand about their affective states? When a human is tested, s/he can offer their subjective experience of what was felt - a person has self-awareness or introspection. Does the cat know that it just experienced rage? Or does it simply react to internal cues without any self-awareness?

Perhaps it requires a cerebral cortex (the primate brain) for awareness of affective states to develop. Research in this realm over the next couple of decades should be very interesting.

Asma is the author of seven books, including Against Fairness: In Favor of Favoritism (2012), On Monsters: An Unnatural History of Our Worst Fears (2008), Stuffed Animals and Pickled Heads: The Culture and Evolution of Natural History Museums (2003), The Gods Drink Whiskey: Stumbling Toward Enlightenment in the Land of the Tattered Buddha (2006), Why I Am a Buddhist: No-Nonsense Buddhism with Red Meat and Whiskey (2011), and the best selling Buddha A Beginners Guide (1996, reissued in 2008).

Animal spirits

The more we learn about the emotions shared by all mammals, the more we must rethink our own human intelligence

by Stephen T Asma

Close cousins: a gorilla family in Rwanda. Photo by Charles L Harris/Gallery Stock

~ Stephen T Asma is professor of philosophy and distinguished scholar at Columbia College Chicago. His latest book is Against Fairness: In Favor of Favoritism.

‘If he grabs you, just go limp and let him throw you around. If you tense up, he’ll take it as a dominance challenge.’

‘Um. Okay.’

My brothers and I looked at each other. This was last-minute advice. We were clinging at a 45-degree angle to the Mount Bisoke volcano, having hacked and crawled for three hours through stinging nettles. We started out in Rwanda; now we were in the Congo. Of course we weren’t supposed to be there, but mountain gorillas don’t respect national borders. With our machete-wielding guides, we had found the gorilla group called ‘Amahoro’, Kinyarwanda for ‘peace’. I just hoped they were in a peaceful mood today.

Before coming to Africa, I had just finished writing a review of America’s two new mother-ship museum exhibits: the Koch Hall of Human Origins at the Smithsonian in Washington DC, and the Spitzer Hall of Human Origins at the American Museum of Natural History in New York. Like every other presentation of our prehistory, these otherwise excellent exhibits focused on the evolution of our big neo-cortical brains — the adaptive significance of tool use, linguistic ability, increasing cultural sophistication. I guess it seems natural to celebrate the development of our unique cognitive abilities, since these distinguish us from our mammal relations.

Out in the bush, however, I began to appreciate how biased this cognitive picture really is. We owe a debt to our big neo-cortices, but our survival owes much more to the emotional skills that were under construction in mammals long before the Homo sapiens cortex explosion. We share a rich emotional life with our animal brethren because emotions helped us all survive in a hostile world. Indeed, the more we understand what mammals have in common, the more we have to rethink everything about even our specifically human intelligence.

On the side of the volcano, my brothers and I caught our breaths. ‘Okay,’ said our guide with a smile. ‘Let’s go see our cousins.’

Outside my tent in the Serengeti, a week before our gorilla trek, I looked up at the Milky Way. It was clearly visible — downright sublime — unlike the starless Chicago sky back home. It is the same awe-inspiring canopy that our ancestors, Homo sapiens, peered up at 200,000 years ago. My brothers and I were camping in the cradle of hominin evolution. Hyenas laughed in the distance.

For days we had been riffing on Stanley Kubrick’s film 2001: A Space Odyssey, which putatively takes place somewhere in this Rift Valley. I kept picturing a mysterious alien monolith in the distance and singing bad versions of the film’s opening fanfare, Thus Spake Zarathustra by Richard Strauss. My brothers countered with a barrage of sci-fi references such as The Land Before Time, Quest for Fire, 10,000 BC, and the classic hominid regression of William Hurt in Altered States. In our own puerile way, we were trying to process the emotional climate of our primordial landscape.

The fear is palpable. That part is not abstract or philosophical — it permeates almost every moment on the Serengeti. If I get out of the truck, these lions will eat me. If I try to cross this little river, the crocs will shred me in minutes. Even the comic, bulbous-bodied hippo is menacing in person. They kill more humans than any other animal in Africa. I watched a hippo fight explode in front of us, and it seemed to shake the ground itself.

One thing you gradually begin to understand in this ancestral environment is the inevitability of death. The carnage is so predictable that a good tracker can judge the trajectories of prey and predators, and then park the safari truck in a prime spot to watch. This is no scam. Crocs have to eat. Wildebeest have to drink. Add those facts together and bloody spectacle inexorably follows.

One morning we broke camp early, climbed into our safari truck and raced off-road through the scrub to a rapidly shrinking creek. Our tracker Mohammed had received a walkie-talkie tip from another tracker that a herd of wildebeest was preparing to cross. Mohammed knew that crocs would be sunning themselves nearby, and that drama might ensue. For a guy who had been tracking these animals for the past 15 years, he seemed as excited as we were. Parked on a riverbank, we watched in silence as wildebeest sniffed at the water’s edge. They moaned and paced anxiously while reptile eyes began to multiply above the water line.

Wildebeest, it turns out, are really dumb. Mohammed explained that if zebras start to cross a waterway and lose just one of their number, they usually cancel the mission, back up the herd and look for alternative passage. Wildebeest, by contrast, will continue to throw themselves into the croc-filled water. Once they’ve committed to crossing, through some tipping-point of group emotion, they seem incapable of modifying or adapting to the new situation. Panic sets in and the wildebeest leap into the fray, snapping their own legs, breaking their backs, drowning each other.

As we were watching, a woman in our party began to scream. She’d seen a lone wildebeest venture too far — only a metre off the shallows — and then a croc leapt up. The herd started to run; pandemonium ensued. Only when the other animals had disappeared into the distance did the crying of the luckless victim go quiet. In preternatural silence, it pulled itself toward the shore, revealing a giant crocodile fastened onto its hindquarters. A back leg was already down the reptile’s throat, the rump locked by razor-sharp front teeth.

‘This is now a waiting contest,’ Mohammed explained. ‘The croc will never let go.’ The wildebeest was stronger than I expected, but it couldn’t overcome the croc. Other crocodiles were starting to make their way toward it. Then something surprising happened, something that shocked even the seasoned Mohammed. After about five minutes, the predator tried to adjust its grip. In that fraction of a second, the straining wildebeest shot free and found itself — as startled as any of us — teetering on the shoreline. The woman who had first spotted it cried out in relief. We all felt an exhilarating rush of triumph for the underdog. A happy ending.

Mohammed took the wind out of our sails. ‘He was a breakfast for crocs this morning, but now he is a walking dinner for hyenas tonight.’ True enough, the wildebeest’s leg was now a mangled ribbon hanging loosely off its hindquarters. An easy target. Our city-slicker buoyancy was premature. Nature is not merciful.

* * *

Time on the Serengeti makes you think a lot about the inner life of animals. While the wildebeest is screaming, is it feeling fear like we do? Is it relieved when it’s suddenly free? Is the croc filled with regret? It might seem self-evident to the sentimental pet owner that our fellow creatures have emotions, but science has long been loath to admit it. Yet Jaak Panksepp, professor of veterinary anatomy at Washington State University College, says this is one area where our anthropomorphic tendencies are probably in the right: animals do have complex emotional lives.

Panksepp is the founder of the new field of affective neuroscience. What makes his work especially compelling is that he has learned how to turn the major emotional systems on and off in his animal subjects. The squeamish won’t like some of his experiments — they include removing brain parts of living rodents and sewing two rats together — but the data are important. Using electrical stimulation, he has demonstrated that mammals have emotional/behavioral responses built into the subcortical and limbic parts of the brain.

Panksepp stuck an electrode into the medial hypothalamus of a cat. At first, the animal was perfectly peaceful. When Panksepp administered an electrical charge, it leaped viciously at his head, a hissing spitting tangle of fangs and claws. As soon as he turned off the stimulation, the cat relaxed into a peaceful state and could be petted with no sign of danger. Humans who have had electrical stimulation in the corresponding brain locations also reported intense rage, which lends credence to the idea of animal subjectivity.

Old-school behaviorists, resistant to the idea of animal emotions, might describe what the cat underwent as ‘sham rage’, but Panksepp is biting the bullet and calling it what it looks like — rage. And ethologists who study animal behaviour increasingly accept the idea that fear keeps animals away from predators, lust draws them toward each other, panic motivates their social solidarity and care glues their parent-offspring bonds. Just like us, they have an inner life because it helps them navigate their outer life.
Read the whole article.
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