Tuesday, December 27, 2011


Enter a dolphin's fluid, hyper-social consciousness

Merging dolphin and human brains might let us "see" inside others' bodies <i>(Image: Kurt Amsler/Ardea)</i>
Merging dolphin and human brains might let us "see" inside others' bodies (Image: Kurt Amsler/Ardea)

What if we merged brains with other species? Would we have very different psychology? Or wordlessly swap intimate feelings?  newscientis

I'VE spent years thinking about consciousness and my current obsession is whether we can know anything about what it is like is to be a dog, a dolphin, or a bat. The most influential answer came from philosopher Thomas Nagel in his 1974 paper, "What is it like to be a bat?" Unlike some of the era's behaviourists, who saw animals as little more than automatons that respond to stimulus, Nagel didn't doubt bats had experience, that it was "like something" being a nimble, echo-locating mammal swooping through the night. But he doubted our ability to say anything true about it beyond projection or imagination.
Nagel may be right, but for me the human-to-animal mind question is simply an extreme form of the human-to-human mind question: we can't know another's experience, but there are deep points of overlap we can expand. What follows is from a conversation with two of the smartest people I know in the field: Lori Marino, a comparative neuroanatomist at Emory University in Atlanta, Georgia, and Ben Goertzel, a mathematician, and a former research director of the Singularity Institute for Artificial Intelligence in San Francisco.
JEFF: Imagine that in front of us are the disarticulated brains of a human, a dog and a dolphin. What might we learn by combining the pieces of the animals in unusual ways?
LORI: Something similar is going on in Leipzig. For example, researchers inserted a human gene into a mouse brain, causing it to grow human-like neurons in the language area: the mouse's vocalisations were deeper.
JEFF: Moving to dogs, psychologist Alexandra Horowitz thinks being immersed in a world of layered smells might affect a dog's sense of time because of the historical smell traces around them.
LORI: Dogs out walking can receive stimuli that are remnants of the past because smells hang around. I've heard audition is similar, that if we had a big enough amplifier we could pick up sounds of people who aren't there now, events happening in the past - though no animal has that capacity as far as we can tell.
BEN: For a dog, smell and vision are very synergistic when they are trying to find stuff outside. For humans, hearing and vision tie together, and olfaction not so much. If you had a mind where all three senses worked closely together, that would be interesting. If we could paste brain lobes together, you'd probably get non-linear feedback between lobes that would settle into some unexpected configurations.
JEFF: Yet we also know basic brain structures repeat themselves. A dog's amygdala, say, is a lot like ours, and there is good evidence it does much the same emotional regulation.
LORI: This is part of the complexity of our task. Ben is saying the brain is not just plug-and-play. If you stick a dog's olfactory bulbs onto a human brain, say, there will be reverberations throughout the brain levels. At the same time, once you have a bilaterally symmetrical animal with a brain, that's it, everything else is a variation on the theme. We only do nervous systems one way on Earth.
BEN: There's another interesting point. Like the auditory system, the visual system is largely hierarchical, using linear feed-forward and feed-back connections. If you look at Berkeley neuroscientist Walter Freeman's model of the olfactory bulb, it's more heterarchical. Activity is more chaotic - we see transient structures responding to different recognisable smells. A cognitive system based on olfaction wouldn't be based so much on breaking things down as on completion of patterns. There seems to be no system on Earth with a high level of general intelligence like that. The hierarchical structure may be a very useful heuristic for being intelligent; without it you don't get that smart.
JEFF: The idea of a hierarchy-oriented brain is really important when we talk about higher-level animal consciousness. Take cetaceans. Their huge brains are 30 million years old, about 28 million years older than ours. But they evolved in a totally different medium.
BEN: I published a paper in The Journal of Cosmology on what a consciousness might be like if it evolved in a fluid environment. I was thinking about how human psychology is adapted to solid objects: stuff bouncing off other stuff, resulting in the psychology of causation. You also get the decomposition of wholes into parts. But if you grew up on Jupiter, where the environment consists of fluids of different viscosity and intersecting vortices and solitons, you might have a very different psychology. Our language is based on assembling units, but not all meaningful communication may be that way - that's why cetacean communication is so important.
LORI: This has been discussed as explaining why we haven't "cracked" communication in dolphins. We think in discrete terms because that's the kind of animal we are, we research a whistle repertoire for dolphins and try to figure out what the whistles mean as discrete sounds. It hasn't got us that far. It may be that we are going down the wrong path.
BEN: When we describe something we make it precise, divide it into parts, recombine it - that's how we build words into sentences, and sentences into paragraphs. Dolphin language may harmonise with a quite different way of thinking about the world. Maybe the two ways are complementary, like waves and particles in quantum mechanics. Or maybe they are completely incommensurable perspectives.
LORI: Except there is still a huge overlap with humans to account for. Decades of work tells us dolphins recognise themselves in mirrors, can learn and understand a symbolically based syntactical language, and have very similar memory systems. I suspect we share basic emotions like love, and a sense of humour. As for the emotional brains, dolphins and whales are the only animals I know where the limbic system has dramatically expanded its connections into the cortex. They have an entire paralimbic lobe no other animals have.
JEFF: So cetaceans have these large, emotional brains - and heavily integrated auditory and visual cortexes that may underlie their echolocation. Some scientists argue dolphins and killer and sperm whales may be able to see inside each other's bodies using echolocation - a bit like ultrasound. A dolphin may know if another dolphin is hungry, sick or pregnant.
BEN: Their "self-model" would be dramatically different. If you travel with the same posse, and could see if they were stressed, relaxed, or whatever, you would get a kind of "extended" self. There would still be an individual self because a dolphin has to protect and feed itself, but not the kind of individuated self we have. Presumably a large part of the dolphin cortex is doing this kind of refined spatial/social modelling humans are not good at. If we grafted that into us, we would detect very fine details of the physical movements of people around us. We would want to live in small, naked tribes, walking around looking at and sensing each other. Our inclination would be to have a group-embodied extended self.
LORI: There's been a lot of talk about this extended self. Of course dolphins don't build houses or make weapons - in a very real sense other beings are their substrate. It's interesting to think they may be an example of a species which has taken the herd mentality mind and jacked it up to a whole new level of complexity.
JEFF: So: what is shared and what is distinct? For me, there is a pith of oneness between life forms, and also a multiplicity of difference. I look at a dolphin and know about the feeling of water, of having a body. It's different, but there is an embodied overlap, a shared world.
LORI: In the end, it comes down to where you want to put the lens.newscientis

Jeff Warren wrote The Head Trip (Random House, 2007). He is writing a book on animal consciousness


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