Showing posts with label fMRI. Show all posts
Showing posts with label fMRI. Show all posts

Monday, 15 August 2016

Free Will: Has Philosophy Been Eclipsed by Neuroscience?

Norton Junction. With acknowledgement to Adrian the Rock
By Keith Tidman
We make decisions before we are consciously aware of making them. These are the findings of the latest neuroscientific research. Has neuroscience therefore eclipsed philosophy? Has it taken the lead? Does philosophy have anything left to say?
In a much-publicised experiment, a neuroscientist placed people into a ‘functional magnetic resonance imaging’ (fMRI) machine. The aim was to observe brain activity as test subjects performed an activity. The neuroscientist instructed the subjects to press a button either with their right hand or their left hand – but to pay close attention to when they took the decision as to which hand to use. The results surprised the worlds of both philosophy and neuroscience. The scanner revealed brain activity—the brain unconsciously deciding to press the button—a remarkable seven seconds before the test subjects consciously opted to press it. That is, the subjects’ brains committed to decisions before the subjects became aware of making them.

Why should this be important? Why does it matter?

We assume that free will is fundamental to our humanity. Assumptions about free will—conscious agency—engage people on pragmatic levels. In fact those assumptions are the keystone for society’s notions of responsibility. Codes of morality and law necessarily rest—rightly or wrongly—on free will’s existence. Institutions, from government bodies to systems of justice to religions, are built on that keystone. In the absence of an alternative model that ensures order in society, such rules-based institutions hold people accountable for their actions. Human conduct is judged, and responses—praise and reward, or condemnation and punishment—are rendered accordingly. Society assumes that a person may be held responsible only if that person is a ‘morally responsible agent’, in conscious, intentional control of behaviour.

The cautious conclusion to the fMRI experiment was that consciousness may play no role in what a person decides. Other neuroscientists concur in this, based on the results of different tests. But are our conclusions too hasty? Are the results ironclad?

In the context of conscious control, what does the fMRI test really tell us about free will? Is free will an illusion, a tricked brain, misled intuition—and even just a convenience for society to function? The question typically appears something like this: “At the moment a person decides, could she willingly and freely have decided otherwise?” And if we do not enjoy unbridled (‘libertarian’) free will, do we at least have contingent free will? If free will is an illusion, is that so for only those choices made hastily and with minimal thought? Or does free will describe all our decisions? Philosophers have grappled with free will for millennia, of course. But the role of neuroscience in this arena is more recent—and arguably indispensable. This dual track of philosophers and neuroscientists makes it necessary to delineate what unique competencies each field brings to free will. But what are they? And do they each have a role?

By and large, both philosophers and neuroscientists today acknowledge the  cause-and-effect nature of brain activity (the physics, chemistry, biology) and decisions—mind-brain dualism long since having been discarded. Yet our considerations do not end here.

Philosophers, for their part, collaborating with psychologists and anthropologists and others, bring a deep understanding of human behavior. This understanding exists in the context of the roles of institutions and culture in society, informing the ways people make decisions, including whether freely or mechanistically. Philosophers also contribute an understanding of the centuries-long history of conceptualising free will and its alternatives, especially how some of the most brilliant minds have described and debated free will and determinism and the concepts’ variants. This process includes placing those historical notions of free will to the litmus test of analytical logic, to assess soundness. All this vitally informs the science—outside the standard domain of scientists—to ensure that the science remains conceptually and historically grounded.

For their part, neuroscientists, collaborating with physicists and biologists, structure hypotheses and bring increasingly sophisticated technologies and rigorous methodologies to understand cognitive brain function. They correlate those functions to the brain as it makes a decision and the person subsequently is aware of the decision. The aim is to explore—tangibly record and measure through technology—what is happening at the unconscious and conscious levels, and to do so involving more complex decision-making. Independent scientists must duplicate test results. For neuroscientists, this unique framing of the free will-versus-determinism puzzle takes into account diverse factors.  These include the neurons and synapses firing in different regions of the brain, perceptions of reality, people’s genetic makeup, the environment influencing genes’ expression (epigenetics), psychological states, and others. How these factors bear on outcomes of science’s take on free will remains to be explored.

Allowing for the distinctly separate competencies of philosophers and neuroscientists, tackling free choice can best be accomplished jointly: defining the problem, examining alternative models, conjuring hypotheses, developing methods, describing initial conditions, teasing out empirical data, interpreting results. Wherein, it seems, lies the best hope of resolving the free-will debate. Philosophy is far from eclipsed.