Scitech  Mental metaphors

Prof talks "new" neuroscience and technology

Brains lag behind. On March 11, approximately 80 professors and students gathered to hear Cornelius Borck’s talk about the technology used to monitor the brain – and how the technology’s speed surpasses that of the mind, yet is still unable to accurately understand it. In “Mind the Gap,” the fourth lecture of the cross-Canada series Trust in New Sciences, Borck provided insight about neuroscience itself, and whether or not we should trust this comparatively new science.

“The title of this lecture series sounds morally charged and invokes a sense of obligation as if on behalf of good citizenship, so to speak, we should trust where the sciences are going,” said Borck, who holds the Canada Research Chair in Philosophy and Language of Medicine.

Proceeding to outline the past 150 years of neuroscience’s history, Borck began with Hermann von Helmholtz, a physicist who measured the velocity of nerve impulses in the 19th century. Helmholtz created a time gap between signal and cognition, and since then new technological advances have helped fill this gap. In fact, these advances even surpass the brain. We are sorting out the brain’s unknown future while still processing what has happened.

Today, almost all of the theories we make regarding the brain are metaphors.

Wilder Penfield used an electrode in an attempt to show that the brain was like a very special tape recorder, which recorded events from a subjective internal perspective. Over time, many similar mechanical metaphors have been used, such as Charles Sherrington’s enchanted loom. But researchers of the early 20th century would not understand why we compare machines to the brain because they emphasized its intrinsic biological nature.

Then, new cellular biology discoveries, along with Darwin’s theory of evolution, contributed to the popularity of a biological model of the brain. This analogy drew from the most basic organisms, linking a jellyfish’s feelers to sensory fibres and its tentacles to neurons.

Non-visual metaphors, such as Freud’s, were also used. He invited people to try and simultaneously imagine all the buildings ever to have existed in Rome, stating that the brain could only be described with language.

A new metaphor replaced all these when electroencephalography, or EEG, was first discovered. Brain waves paved the way for the most powerful and important technological analogy of all: the computer. Both body and machine use electricity. The all-or-nothing principle of signal transmission also agreed with the computer’s binary code. But paradoxically, it was an IBM computer’s victory over chess master Garry Kasparov that made this metaphor falter. While computers were more intelligent in their ability to perform calculations, they were also clumsier than humans, in the case of robotic bodily movements. These observations all led to the fall of the computer metaphor.

Borck wonders what metaphor will be next – an iPhone, the Internet? Thankfully, the decline of the computer metaphor coincided with the rise of neuroimaging, such as magnetic resonance imaging. This powerful new tool showed both structural and functional details of specific brain activations. Models and metaphors failed at describing the brain because they focused on the differences between object and concept. These images conflated the object with its representation.

Neuroscience is highly efficient at complicating its subject matter. Every answer leads to many more questions. With so many neuroscientists around the world, the brain story is bound to get ever more complex. And in light of the historical persistence of different theories and “almost there” metaphors, maybe this new science isn’t very reliable.

But Borck believes that neuroscience research should keep going, even if it means making the problem even more complex. “If anything, it is the hanger-ons of the imminent elucidation of the mind brain which limit the future,” he said.

Who knows how people 100 years from now will scoff at our trust in coloured brain images, but even if these imaging techniques still leave the question open-ended, they allow neuroscience to keep moving forward.