38. See, for example, R. A. Sherman et al., «Chronic Phantom and Stump Pain Among American Veterans: Results of a Survey,» Pain 18:83–95 (1984).
39. S. W. Mitchell, «Phantom Limbs,» Lippincott's Mag. Pop. Lit. & Sci. 8:563–569 (1871).
40. See V. S. Ramachandran et al., «Scientific Correspondence: Touching the Phantom Limb,» Nature 377:489–490 (1995); V. S. Ramachandran & D. Rogers-Ramachandran, «Synaesthesia in Phantom Limbs Induced with Mirrors,» Proc. Roy. Soc. Lond. B:377–386 (1996); and V. S. Ramachandran & Sandra Blakeslee, Phantoms in the Brain (New York: William Morrow, 1998).
41. V. S. Ramachandran, «Consciousness and Body Image: Lessons from Phantom Limbs, Capgras Syndrome and Pain Asymbolia,» Phil. Trans. Roy. Soc. Lond. B353:1851-9 (1998). For clinical and experimental details, see Ramachandran and Rogers-Ramachandran, «Synaesthesia in Phantom Limbs» (1996).
42. P. Brugger et al., «Beyond Re-membering: Phantom Sensations of Congenitally Absent Limbs,» Proc. Nat. Acad. Sci. USA 97:6167-72 (2000).
43. See § 12 and § 13 of The Ethics.
CHAPTER 4
1. Adapted from the case report of a sixty-eight-year-old woman suffering from stroke-related, transient alien hand syndrome. From D. H. Geschwind et al., «Alien Hand Syndrome: Interhemispheric Disconnection Due to Lesion in the Midbody of the Corpus Callosum,» Neurology 45:802–808 (1995).
2. See K. Goldstein, «Zur Lehre der Motorischen Apraxie,» Jour. fur Psychologie und Neurologie 11:169–187 (1908); W. H. Sweet, «Seeping Intracranial Aneurysm Simulating Neoplasm,» Arch. Neurology & Psychiatry 45:86-104 (1941); S. Brion & C.-P. Jedynak, «Troubles du Transfert Interhemispherique (Callosal Disconnection). A Propos de Trois Observations de Tumeurs du Corps Calleux. Le Signe de la Main Etrangere,» Revue Neurologique 126:257–266 (1972); G. Goldberg et al., «Medial Frontal Cortex Infarction and the Alien Hand Sign,» Arch. Neurology 38:683–686 (1981). For an important new conceptual distinction, see C. Marchetti & S. Della Sala, «Disentangling the Alien and the Anarchic Hand,» Cog. Neuropsychiatry 3:191–207 (1998).
3. Goldberg et al., «Medial Frontal Cortex Infarction,» 684 (1981).
4. G. Banks et al., «The Alien Hand Syndrome: Clinical and Postmortem Findings,» Arch. Neurology46:456–459 (1989).
5. Ibid.
6. For more on the representational architecture of volition and akinetic mutism, see T. Metzinger, «Conscious Volition and Mental Representation: Towards a More Fine-Grained Analysis,» in Natalie Sebanz & Wolfgang Prinz, eds., Disorders of Volition (Cambridge, MA: MIT Press, 2006).
7. S. Kremer et al., Letter to the Editor, «The Cingulate Hidden Hand,»
Jour. Neurology, Neurosurgery, and Psychiatry 70:264–265 (2001); see also a classical study by I. Fried et al., «Functional Organization of Human Supplementary Motor Cortex Studied by Electrical Stimulation,» Jour. Neurosci. 11:3656-66 (1991). In this study, subjects stimulated with electrical currents of different strength reported the illusory conscious perception of ongoing movement, or the anticipation of movement, or the «urge» to perform a movement, all «in the absence of overt motor activity.»
8. D. M. Wegner & T. Wheatley, «Apparent Mental Causation: Sources of the Experience of Will,» Amer. Psychol. 54(7):480–492 (1999).
9. Wegner & Wheatley, «Apparent Mental Causation» (1999), 488.
10. Ibid., 483.
11. See, for instance, P. Haggard, «Conscious Awareness of Intention and of Action,» in Johannes Rossler & Naomi Eilan, eds., Agency and Self-Awareness-Issues in Philosophy and Psychology (Oxford, UK: Clarendon Press, 2003). A good recent review is Patrick Haggard, «Human Volition: Towards a Neuroscience of Will,» Nat. Rev. Neurosci. 9:934–946 (2008).
12. It is true that indeterminacy exists on the subatomic level, but the mind cannot somehow sneak into the physical world through indeterminate quantum processes. (Nor is chance what we want: Philosophically, randomness in the brain would be just as bad as full determination.) Quantum theories of free will are empirically false as welclass="underline" There may be different kinds of brains somewhere else in the universe, but in human brains the firing of neurons and so on take place on the macroscopic scale. For such huge objects as nerve cells at 37°C body temperature, quantum events simply play no role.
13. The voluntary inhibition of voluntary actions seems to be mostly determined by unconscious events in the anterior median cortex. See M. Brass & P. Haggard, «To Do or Not To Do: The Neural Signature of SelfControl,» J. Neurosci. 27:9141–9145. (2007).
14. See T. Metzinger, «The Forbidden Fruit Intuition,» The Edge Annual Question-2006: What Is Your Dangerous Idea? www.edge.org/q2006/ q06_7.htmlfflmetzinger. Reprinted in J. Brockman, ed., What Is Your Dangerous Idea? Todays's Leading Thinkers on the Unthinkable (New York: HarperPerennial, 2007), 153–155.
15. It would not be a new thought in the history of philosophy. Vasubandhu, a fourth-century Buddhist teacher and one of the most important figures in the development of Mahayana Buddhism in India, reports: Buddha has spoken thus: 'O, Brethren! actions do exist, and also their consequences (merit and demerit), but the person that acts does not. There is no one to cast away this set of elements and no one to assume a new set of them. (There exists no individual), it is only a conventional name given to (a set) of elements.' Appendix to the VIIIth chapter of Vasubandhu's Abhidarmakoga, § 9: 100.b.7; quoted after T. Stcherbatsky, «Th Soul Thory of the Buddhists,» Bull. Acad. Sci. Russ. 845 (1919).
CHAPTER 5
1. The second question, of course, is the one Descartes asked in the first Meditation, when he realized that everything he had ever believed to be certain-including his impression of sitting by the fire in his winter coat and closely inspecting the piece of paper in his hands-could equally well have occurred in a dream. What makes the problem of dream skepticism so intractable is that even in a «best-case scenario» of sensory perception, there is apparently no reliable, fool-proof method of distinguishing wakefulness and dreaming. According to dream skepticism, literally all of our experiences of waking life could be nothing more than a dream, and we are unable, even in principle, ever to decide this question with certainty. For a detailed discussion of the problem of dream skepticism, see, for instance, Barry Stroud, The Significance of Philosophical Scepticism (New York: Oxford University Press, 1984). For the status of the phenomenal and the epistemic subject in the dream state, see J. Windt & T. Metzinger, «The Philosophy of Dreaming and Self-Consciousness: What Happens to the Experiential Subject During the Dream State?» in Patrick McNamara & Deirdre Barrett, eds., The New Science of Dreaming (Westport, CT: Praeger, 2007). See http://eprints.assc.caltech.edu/200/01/Dreams.pdf.
2. See J. A. Hobson et al., «Dreaming and the Brain: Toward a Cognitive Neuroscience of Conscious States,» Behavioral and Brain Sci. 23:793–842 (2000); and Antti Revonsuo, Inner Presence: Consciousness as a Biological Phenomenon (Cambridge, MA: MIT Press, 2006).
3. Helen Keller, The World I Live In (New York: New York Review Books, 2003).