John Krakaeur, a neuroscientist at Johns Hopkins Hospital, has been asked to BRAIN Initiative meetings before, and describes it like “Maleficent being invited to Sleeping Beauty’s birthday.” That’s because he and four like-minded friends have become increasingly disenchanted by their colleagues’ obsession with their toys. And in a new paper that’s part philosophical treatise and part shot across the bow, they argue that this technological fetish is leading the field astray. “People think technology + big data + machine learning = science,” says Krakauer. “And it’s not.”
He and his fellow curmudgeons argue that brains are special because of the behavior they create—everything from a predator’s pounce to a baby’s cry. But the study of such behavior is being de-prioritized, or studied “almost as an afterthought.” Instead, neuroscientists have been focusing on using their new tools to study individual neurons, or networks of neurons. According to Krakauer, the unspoken assumption is that if we collect enough data about the parts, the workings of the whole will become clear. If we fully understand the molecules that dance across a synapse, or the electrical pulses that zoom along a neuron, or the web of connections formed by many neurons, we will eventually solve the mysteries of learning, memory, emotion, and more. “The fallacy is that more of the same kind of work in the infinitely postponed future will transform into knowing why that mother’s crying or why I’m feeling this way,” says Krakauer. And, as he and his colleagues argue, it will not.That’s because behavior is an emergent property—it arises from large groups of neurons working together, and isn’t apparent from studying any single one.
Tuesday, February 28, 2017
More than neurons
Ed Yong has stopped writing his blog, but here he is at The Atlantic, with a good article about some neuroscientists getting sick of the approach of other neuroscientists. A sample:
...If we fully understand the molecules that dance across a synapse, or the electrical pulses that zoom along a neuron, or the web of connections formed by many neurons, we will eventually solve the mysteries of learning, memory, emotion, and more.
ReplyDeleteHow many lay people are aware that the standard model of the neuron is in serious trouble, or about volume transmission, axon-axonic connections, post synaptic modulations, backward propagation, retrograde inhibitors, inverse agonists, ... . These are what neuroscience should be about, not pretty lights, simple behavior-neural correlate analyses, and endlessly babbling about the question of consciousness.
Their comments relate to something I used to argue: trying to understand the brain without reference to the environment is like trying to study aerodynamics on the moon.
...That’s because behavior is an emergent property—it arises from large groups of neurons working together, and isn’t apparent from studying any single one.
Of course the bods are aware of that. The above is a straw man argument. The point is: how are we going to understand emergence if we don't understand the fundamentals of neural transmission? (Climate is emergent, we build models of that by understanding discrete processes.) For example, the work of Matt Jones at Wisconsin Uni, those beautiful images of GABA diffusion. They are creating a false dichotomy, as if because behavior is emergent it is separate from neural activity and we can learn nothing by studying discrete neurologic processes. Just because a phenomenon is emergent doesn't mean we can't learn something useful by studying discrete elements within that phenomenon.
...Ghazanfar agrees. “If your goal is to understand the brain, you have to understand behavior, and that’s not trivial. I think a lot of neuroscientists think it is,”
Behaviorists have been making the same point for 50 years: if we don't reference behavior we can't understand brains.