Neuroethics Journal Club: Autonomous Linguini
How responsible are people for their decisions? Can neuroscience help us answer that question? If not, can a Pixar movie about a cooking rat help clear things up? If you’re stumped by these questions, you may have missed the most recent meeting of the Emory Neuroethics Program’s journal club. Those of us that were there took part in a discussion led by Jason Shepard, graduate student in the Wolff lab and Neuroethics program scholar. You can thank him for the reference to the Pixar film, Ratatouille. He used the plot of the movie to get us talking about the paper we read, “How the neuroscience of decision making informs our conception of autonomy”, by Gidon Felsen and Peter Reiner. Jason got us talking so much that we kept him from making all the points he wanted to about the paper—look for a blog post from him soon. To introduce the paper, I’ll recap his “Autonomous Linguini” though experiment:
The movie Ratatouille tells the story of Alfredo Linguini, who works as a lowly garbage boy at a restaurant until his run in with the rat Remy. When Linguini spills a pot of soup, Remy saves his hide by helping him re-create it—luckily, Remy is not just a rat but also a gifted chef. Customers love the soup, and suddenly Linguini finds himself a cook-in-training. How will the hapless Linguini survive in the kitchen? Naturally, he will let Remy control him, like a marionette, by yanking on his hair. Here’s the question: is Linguini making autonomous decisions in the kitchen when he cedes control to Remy?
Autonomy is the ability to make decisions rationally and free from outside influence. While Linguini's autonomy may not matter much to you, the extent to which people are responsible for their decisions concerns philosophers, bioethicists, and lawyers alike. Some might argue that if we knew how the brain arrives at decisions, then we could resolve all sorts of long-standing ethical and moral debates. For example, knowing how the brain decides could help us choose between systems of government. Maybe we need a nanny state, because people have to be saved from their poorly designed brains, or maybe we need a night watchman state, because people’s brains make great decisions once freed from the feds.
Now that I've introduced autonomy, let's get to the article we discussed in journal club, in which Felsen and Reiner attempt to do two things: (1) present a "standard model" of autonomous decisions, and (2) discuss whether evidence from neuroscience supports the standard model. While I don't think anyone at this meeting of the journal club had a problem with the idea that neuroscience can inform the debate on autonomy, many took issue with how Felsen and Reiner fleshed out that idea.
Autonomy is the ability to make decisions rationally and free from outside influence. While Linguini's autonomy may not matter much to you, the extent to which people are responsible for their decisions concerns philosophers, bioethicists, and lawyers alike. Some might argue that if we knew how the brain arrives at decisions, then we could resolve all sorts of long-standing ethical and moral debates. For example, knowing how the brain decides could help us choose between systems of government. Maybe we need a nanny state, because people have to be saved from their poorly designed brains, or maybe we need a night watchman state, because people’s brains make great decisions once freed from the feds.
Now that I've introduced autonomy, let's get to the article we discussed in journal club, in which Felsen and Reiner attempt to do two things: (1) present a "standard model" of autonomous decisions, and (2) discuss whether evidence from neuroscience supports the standard model. While I don't think anyone at this meeting of the journal club had a problem with the idea that neuroscience can inform the debate on autonomy, many took issue with how Felsen and Reiner fleshed out that idea.
The authors identify three criteria that a decision must meet to be autonomous. Let me focus on one, just to give an idea of how their article was received. Their first criterion states that, to be autonomous, a decision must be consistent with the “’higher order’ beliefs and desires” of an individual. The phrase “higher order … desires” refers to the idea, found in the writings of philosopher Harry Frankfurt, that desires can be ranked in a hierarchy. “[P]hysiological needs” like hunger and “reflexive emotions” are first-order desires, and desires about those desires are second-order or higher. Consider Felsen and Reiner’s example: you are in the lunch line at a cafeteria, facing a decision between salad and cake. Your desire to eat is first-order; your desire to eat salad because you don’t want to gain weight is higher order.
What does neuroscience have to say about our ability to rank desires and choose between them? Plenty, according to Felsen and Reiner. They claim that the brain has a hierarchical organization, like desires, so that lower-order desires map onto the brainstem and higher order desires map onto the cortex. Decisions can be autonomous, then, because the pre-frontal cortex can modulate activity in areas involved with lower-order desires and tip the scales in favor of one lower-order desire over another. Felsen and Reiner acknowledge—in a footnote—that there are other models of how the brain makes decisions, where the pre-frontal cortex is not in control, but then state that “specific brain regions constituting each level of the hierarchy are not critical for the purposes of our discussion."
Unfortunately, if the authors want to constrain the debate on autonomy with neuroscience, the details do matter. They’re right that neuroanatomy suggests the brain is hierarchically organized, but whether it acts that way in real time is another question. More on that below. They are not right when they state that the brainstem evolved before other brain areas. As someone with a background in brain evolution, and with aspirations to being a crotchety old man, I have to point this out. To the contrary, we know that all of the major brain structures, from brainstem to cortex, are present in almost all extant vertebrates, in one form or another. I’ll muzzle my inner old man for a second, and assume that Felsen and Reiner wanted to say something like, “the fact that during evolution the human brain underwent a massive expansion in the size of the cortex has allowed people to have more autonomy”. That statement might let them hold on to their hierarchy. However, it’s probably more useful to think of brains as highly inter-dependent networks than to think of them as hierarchies. Different nodes in the network take control at different times. When we’re deciding whether to cut someone off on the highway, we might be relying on our basal ganglia. This description of decisions brings to mind Daniel Dennet’s “multiple drafts” model of consciousness, as Steve Potter pointed out at the journal club meeting. Similarly, different regions of the pre-frontal cortex might process different inputs to help modulate between desires. During our discussion, neuroscience graduate student Kathy Reding brought up the hypothesis that the ventromedial part of prefrontal cortex processes somatic signals, i.e., sympathetic responses that let us tag certain events emotionally. (Felsen and Reiner also discuss the somatic marker hypothesis as it relates to their second criterion.)
What does neuroscience have to say about our ability to rank desires and choose between them? Plenty, according to Felsen and Reiner. They claim that the brain has a hierarchical organization, like desires, so that lower-order desires map onto the brainstem and higher order desires map onto the cortex. Decisions can be autonomous, then, because the pre-frontal cortex can modulate activity in areas involved with lower-order desires and tip the scales in favor of one lower-order desire over another. Felsen and Reiner acknowledge—in a footnote—that there are other models of how the brain makes decisions, where the pre-frontal cortex is not in control, but then state that “specific brain regions constituting each level of the hierarchy are not critical for the purposes of our discussion."
Unfortunately, if the authors want to constrain the debate on autonomy with neuroscience, the details do matter. They’re right that neuroanatomy suggests the brain is hierarchically organized, but whether it acts that way in real time is another question. More on that below. They are not right when they state that the brainstem evolved before other brain areas. As someone with a background in brain evolution, and with aspirations to being a crotchety old man, I have to point this out. To the contrary, we know that all of the major brain structures, from brainstem to cortex, are present in almost all extant vertebrates, in one form or another. I’ll muzzle my inner old man for a second, and assume that Felsen and Reiner wanted to say something like, “the fact that during evolution the human brain underwent a massive expansion in the size of the cortex has allowed people to have more autonomy”. That statement might let them hold on to their hierarchy. However, it’s probably more useful to think of brains as highly inter-dependent networks than to think of them as hierarchies. Different nodes in the network take control at different times. When we’re deciding whether to cut someone off on the highway, we might be relying on our basal ganglia. This description of decisions brings to mind Daniel Dennet’s “multiple drafts” model of consciousness, as Steve Potter pointed out at the journal club meeting. Similarly, different regions of the pre-frontal cortex might process different inputs to help modulate between desires. During our discussion, neuroscience graduate student Kathy Reding brought up the hypothesis that the ventromedial part of prefrontal cortex processes somatic signals, i.e., sympathetic responses that let us tag certain events emotionally. (Felsen and Reiner also discuss the somatic marker hypothesis as it relates to their second criterion.)
If it’s just a matter of figuring out how we choose between lower-order desires though, then Felsen and Reiner might respond that I haven’t presented a problem for their first criterion. They already said that the details of the hierarchy don’t matter. I would say that we do have a problem, though, if it takes the whole network to make an autonomous decision. The problem is that we’re going to have to do a lot more neurosciencing before we can decide (hello, irony) whether certain decisions are autonomous. Currently, America's legal system has a certain concept of what decisions are autonomous that depends on the mental state of the person that made them, as we talked about at the journal club meeting. If you drink a bottle of Jack Daniels and then sign a contract, you can’t be held responsible, but if you drink the same bottle, get into your car, and then drive that car through the plate glass windows of a bank, you can be held responsible. These cases seem like no-brainers (pardon the pun), but the legal landscape will likely turn treacherous as we learn more about the brain. What if I’m a recovering alcoholic with enlarged cerebral ventricles and I drive my car through the plate glass windows of a bank? How will we handle decisions made by people with brain injuries? Schizophrenics?
Few of us can pretend to have a command of both the nuances of neuroscience and the philosophy of autonomy, but Felsen and Reiner have taken the first steps toward reconciling the two. Maybe we can hash out the details over a plate of autonomous linguini (sorry, my family is genetically predisposed towards puns).
The Neuroethics Program journal club will meet again on February 22nd from 12:30-1:30pm. Neuroethics Program Associate Dr. Gillian Hue will facilitate a discussion of "Examining the Effects of Sleep Deprivation on Work-place Deviance". If you’d like to get in on the discussion of the pons, politics, or pasta, be sure to RSVP by sending an e-mail to neuroethics@emory.edu.
--David Nicholson
Emory Neuroscience Graduate Student, Sober lab
Want to cite this post?
Nicholson, D. (2012). Neuroethics Journal Club: Autonomous Linguini. The Neuroethics Blog. Retrieved on , from http://www.theneuroethicsblog.com/2012/02/neuroethics-journal-club-autonomous.html
