Tuesday, May 19, 2015

Forget the Map; Trust Your Brain: The Role Neuroscience Plays in Free Will

by Fuad Haddad

The following post is part of a special series emerging from Contemporary Issues in Neuroethics, a graduate-level course out of Emory University’s Center for Ethics. Fuad is an undergraduate junior at Emory studying neuroscience and behavioral biology and ethics. He currently performs research at Yerkes National Primate Research Center under Dr. Larry Young, studying the relationship of single nucleotide polymorphism and pair bonding. His other research interests are the relationship between oxytocin and allopatric grooming as a model of empathy. 

Lizzie laughs as we drive down Briarcliff. “What do you mean an adventure?” she chuckles at me. I have a propensity to get lost for fun, an unhealthy and interesting habit. We approach a stop light. “Left, right, straight – pick one!” I say. As we arrive at a consensus, we journey onward until we reach a green highway sign that signals the exit to Athens. Her smile gives her motive away; I think, “Sorry Emory, but I’m going to be a Bull Dog today.” 

Take a moment to fast forward four months. On a September afternoon, I sit in the same car, with the same girl, leaving from the same place. “Left, right, straight?!” I ask again. Like before, we haphazardly trek through the jungle of northeast Atlanta. In the midst of yet another game of “where can we get lost now?” a peculiar phenomenon occurs. Slamming on the brakes, the car comes to a halt. Almost instantaneously we both realize that in this seemingly random choice in direction, our choices lead us back to the same green sign again and even more interestingly, through the same path. 
I guess Robert Frost isn’t going to Athens. From southeastroads.com

Consequentially, this scenario kindled a discussion regarding my ability to make decisions. Within the same environment, how, under the presumption of voluntary action, was I was able to reenact temporal steps to guide me to the same location? Therefore, my thoughts diverted towards the idea of my free will and subsequently, the process in which I ostensibly choose my voluntary actions. These inquiries lead to a discussion with Dr. Banja, a professor at the Emory Center for Ethics, in which he presented an interesting perspective that resonated with me.  

“Could Have Chosen Otherwise - Under Identical Conditions” (CHACO-UIC) is what it sounds like – if under identical conditions, down to the sub-atomic level, an agent could have performed contrary to the original action. The paradigm is a standard tool for separating two trains of thought on free will: libertarianism and determinism. Libertarianists would agree with CHACO-UIC premise while determinists would not (PFW 4.1). Banja antiquates CHACO-UIC by attacking its ecological validity. The ecological validity of CHACO-UIC stands upon the faulty premise that all conditions can be identically replicated. Within choices exist coupling factors determined by our previous actions. How can one determine humankind’s first unpreceded action? Therefore, Dr. Banja has made a hybrid contra-causal stance with his theory of “adaptive” free will. 

By decaying CHACO-UIC, the choosing of free will can now be classified as “adaptive” rather than “otherwise.” Free will then arises from “an ineluctable product of bioevolutionary processes.” Couched in a somewhat deterministic approach (where biology does determine behavioral processes), he credits decision-making to the "smart" choices organisms must make to adapt and survive in a dynamic environment (Banja 1). While Dr. Banja mentions the importance of the brain-based mechanisms of intentionality, the question still remains regarding the mechanisms by which this occurs. 

One example that illustrates a brain-based mechanism of intentionality is a study performed by Drs. Packard and McGaugh. In this hallmark experiment they trained a set of rats in a T-maze to determine which arm contained a reward (in this case, a food pellet). The standard paradigm is to switch the orientation of the apparatus to determine if the rat responds by going left or right. 

During the experiment, researchers lesioned specific brain regions in arrays, the hippocampus and the caudate nucleus. They found that the hippocampus mediates spatial memory while the caudate mediates stimulus-response learning. In addition, spatial learning was acquired before stimulus-response learning (Packard 65). 

Although the projected study used rats as a model, several other studies exhibit similar claims using human subjects (Schwabe et al., Skelton et al.) In the context of my situation, the first time I wandered in my car, I had somewhat of a spatial dependent awareness of where I was. Unfamiliar with my current situation, I relied on the crossroads and visual cues that my hippocampus used to guide me to my goal (Athens). However, the second time might have been dictated by a stimulus-response pathway (habit of turning left, left, and right) in the same temporally acquired order as the rat experiment. 

Working back towards the idea of “adaptive” free will, the results of this experiment display that there exist fundamental feedback loops in the brain, a neurological basis. Proponents may argue that the evidence of a neurological basis disproves the capacity of free will; I argue that such neurological basis provides the deterministic answers for the “adaptive” model. The niche of neuroscience regarding free will then lies in revealing the determinism of our actions. The future of our conceptualizations of free will then sits not upon the throne of introspection, but the illuminating neurological discoveries that may come. 

References

Banja, John. "Could Have Chosen Otherwise under Identical Conditions: An Evolutionary Perspective on Free Will" AJOB Neuroscience, In Press. Web.

Packard, M. "Inactivation of Hippocampus or Caudate Nucleus with Lidocaine Differentially Affects Expression of Place and Response Learning." Neurobiology of Learning and Memory 65.1 (1996): 65-72. Web.

Schwabe, Lars, Melly S. Oitzl, Christine Philippsen, Steffen Richter, Andreas Bohringer, Werner Wippich, and Hartmut Schachinger. "Stress Modulates the Use of Spatial versus Stimulus-response Learning Strategies in Humans." Learning & Memory. Cold Spring Harbor Laboratory Press, n.d. Web. 25 Mar. 2015.

Skelton, Ronald W., Cindy M. Bukach, Holly E. Laurance, Kevin G.f. Thomas, and Jake W. Jacobs. "Humans With Traumatic Brain Injuries Show Place-Learning Deficits in Computer-Generated Virtual Space." Journal of Clinical and Experimental Neuropsychology (Neuropsychology, Development and Cognition: Section A) 22.2 (2000): 157-75. Web.

The Problem of Free Will. Retrieved March 24, 2015, from Information Philosopher Web site http://www.informationphilosopher.com/freedom/problem/

Want to cite this post?

Haddad, F. (2015). Forget the Map; Trust Your Brain: The Role Neuroscience Plays in Free Will. The Neuroethics Blog. Retrieved on , from http://www.theneuroethicsblog.com/2015/05/forget-map-trust-your-brain-role.html

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