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Neuroethics Beyond Genethics EMBO/EMBL Nov 3-4, 2006. Adina Roskies Dartmouth College and Sydney University. Neuroethics:. The ethics of neuroscience The ethics of practice Ethical implications of neuroscience The neuroscience of ethics. Ethics of Neuroscience. Neuroscience Of Ethics.
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Neuroethics Beyond GenethicsEMBO/EMBL Nov 3-4, 2006 Adina Roskies Dartmouth College and Sydney University
Neuroethics: • The ethics of neuroscience • The ethics of practice • Ethical implications of neuroscience • The neuroscience of ethics Ethics of Neuroscience Neuroscience Of Ethics
Early thoughts on neuroethics “The question at issue here is how far the knowledge that we have about our brain gives us a new conception of ourselves, a different representation of our ideas, our thoughts and the dispositions that intervene when we make judgments. With regard to moral judgments, in fact, it is fundamental. The knowledge that we are now in the process of piecing together about the human brain ought to allow us to have a clearer idea -- I am perhaps overly optimistic -- of the direction in which we wish to see human society develop…” --J.P. Changeux
Is neuroethics a distinct field? • Is neuroethics a discipline in its own right? • Do the problems it raises differ from those in genethics? Ethics of Neuroscience Neuroscience Of Ethics
The ethical space neuroethics genethics decision-making and freedom consciousness moralcognition future generations access personhood and the self treatment consent normalcy and disease discrimination distributivejustice enhancement
Overlap neuroethics genethics decision-making and freedom consciousness moralcognition future generations access personhood and the self treatment consent normalcy and disease discrimination distributive justice enhancement
Genethics beyond neuroethics neuroethics genethics decision-making and freedom consciousness moralcognition future generations access personhood and the self treatment consent normalcy and disease discrimination distributivejustice enhancement
Neuroethics beyond genethics neuroethics genethics decision-making and freedom consciousness moralcognition future generations access personhood and the self treatment consent normalcy and disease discrimination distributivejustice enhancement
MCS and PVS MCS: minimal awareness of self PVS: no awareness of self Even PVS patients may appear somewhat normal MCS:112,000-280,000 in USA PVS: 14,000-35,000 (Embo reports,2005)
Schiavo case • PVS • Support eventually terminated • Public focus • Autopsy revealed massive irreversible damage
Metabolism in normal and vegetative state normal PVS PVS after recovery Laureys, 2006
Preserved brain activity in MCS Case 2 Case 1 normals Schiff et al (2005): 2 men in MCS show brain activity to familiar audio track, but many differences
Brain damage and consciousness • Lots of brain activity activity occurs during sleep, without awareness etc. • Despite this: “The findings show that some people that doctors had previously declared to be in a Persistent Vegetative State (PVS) are still conscious.”(commentary on the web)
More recent studies Owen et al., 2006
Ethical implications • Methods to assess awareness in brain-damaged patients • Methods can be developed to communicate with patients physically unable to respond • May provide patients with more autonomy, but leaves us with ethical choices to make, nonetheless
Neuroethics beyond genethics neuroethics genethics decision-making and freedom consciousness moralcognition future generations access personhood and the self treatment consent normalcy and disease discrimination distributivejustice enhancement
What is a person? • Personal identity • Neuroessentialism (“We are our brains”) • Psychological or brain-based criteria seem important • Do alterations in brain function alter personal identity? • The self • What is the representation of ‘self’? • Is the self an illusion?
Personhood • On the basis of philosophical disputes and neuroscientific data, Farah and Heberlein (AJOB Neurosciences, forthcoming) argue against personhood as a natural kind
Naturalizing personhood “The real contribution of neuroscience to understanding personhood may be in revealing not what persons are, but rather why we have the intuition that there are persons… instead of naturalizing the concept of personhood by identifying its essential characteristics in the natural world, neuroscience may show us that personhood is illusory, constructed by our brains and projected onto the world” (Farah & Heberlein, AJOB Neurosci, forthcoming)
Our person-intutions • 2 different networks • Person-network (the social brain): Automatic, fast, based on simple perceptual features, issues in yes/no judgments • Object-network: More abstract, analytical, higher cognitive areas; issues in graded judgments • Suggest abandoning the concept of personhood for ethics
What is a person? • An important ethical concept • Doesn’t have to be a natural kind • Neuroscience can help put it in perspective; we can choose what criteria we think are more important
Neuroethics beyond genethics neuroethics genethics decision-making andfreedom consciousness moralcognition future generations access personhood and the self treatment consent normalcy and disease discrimination distributivejustice enhancement
Decision-making in nonhuman primates • Reward circuitry • Midbrain dopaminergic system • VMPFC codes primary reinforcers and reward associations in changing circumstances • Integrative areas in DLPFC and parietal cortex
Similar areas are active in humans in neuroimaging of decision-making tasks • Reward/Emotional circuitry: • VMPFC/OFC: associating outcomes with reward; integrate sensory and limbic signals • Striatum: critical component of dopaminergic reward system • Amygdala: predictive of bad outcome • Insula: associated with risk, punishment • ACC: conflict monitoring, risk • ‘Cognitive’ regions: • DLPFC: online manipulation and integration of decision-relevant information • Posterior parietal cortex: calculation
The problem • Decisions, choices, actions are generally thought to be freely willed • Science reveals them, or threatens to reveal them, to be mechanistically or physically intelligible. • This mechanistic view challenges our intuitions about freedom and its conceptual partner, moral responsibility.
Free will: “By monitoring the signals produced by appropriate neurons, an experimenter can predict and even influence what a monkey will choose…Ethics, not theory, would preclude an investigator from obtaining the same relationship with a human agent. Can this ability to predict and influence be reconciled with a belief in freedom and responsibility?” • Schall, Nature Reviews Neuroscience, 2001
Rethinking freedom and responsibility • The old view: Freedom is • Ability to do otherwise • Absence of constraint
Moral responsibility • We have intuitive senses of when people are appropriate objects of reactive attitudes of praise, blame, respect, etc. for their actions. • The intuitions seem to involve a conception of free action
The regress of being able to do otherwise • To be free is to be able to: • Act otherwise • Choose to act otherwise • Our brains (not our selves) do the choosing • But • Our brains are our selves • We must become comfortable with mind as mechanism
The neuroscience of ethics • Recasting freedom as self-governance: • What mechanisms underlie our ability to control our actions; what failures undercut that ability? • Can we make sense of freedom as self-regulation?
The neurobiology of responsibility • Cognitive demand: • Appropriate representation of moral facts • Representation of self as rational agent? An intentional agent? • Control demand: • Appropriate motivational structures • When a person is in control of his actions, his actions depend on his motivational states • Appropriate links between cognitive and motivational structures • Effective mechanisms of inhibition
Neuroethics beyond genethics neuroethics genethics decision-making and freedom consciousness moral cognition future generations access personhood and the self treatment consent normalcy and disease discrimination distributivejustice enhancement
Neuroimaging results • Overlap with areas involved with general decision making • Activity in regions implicated in emotion, especially in ‘personal’ moral judgments Greene et al., 2001
Difficult - easy personal dilemmas • High RT(counter-intuitive) - low RT (intuitive) ‘personal’ judgments • Override emotional bias with more abstract thought Greene et al., 2004
What does this say about the nature of morality? • Mechanistic? • Does it correspond to something out in the world? • Our intuitions don’t necessary track morally-relevant features of situations • An artifact of how we are wired up? • Do blame and punishment make sense? Retributivism vs. utilitarianism.
Is neuroethics a distinct field? • Do the problems neuroethics raises differ from those in genethics? • Is neuroethics a discipline in its own right? Ethics of Neuroscience Neuroscience Of Ethics
Yes, distinct enough • Neuroethics raises some novel questions • Even when questions are similar, they have distinctive aspects • To some extent, disciplines are socially constructed • Neuroethics deals with sophisticated methodologies and a complex body of data and theory, and requires people trained in both neuroscience and ethics to adequately assess the evidence • Nonetheless, we shouldn’t overlook the debt neuroethics has to bioethical thought that precedes it.