Advances in neurology, neurosurgery, and psychiatry have shown promise of controlling even the most intractable diseases of the brain and mind. Electrical deep-brain stimulation is now considered standard therapy for severe Parkinson disease and is being used to treat obsessive-compulsive disorder, refractory depression, and other conditions. Neural stem cell transplantation and gene transfer therapies may be able to regenerate damaged brain tissue and possibly reverse some neurodegenerative diseases. Psychopharmacology can not only treat cognitive and affective disorders but also enhance normal cognitive capacities.
The new neuroscience also has important ethical, legal, and social implications, as an interdisciplinary group of European neuroscientists, philosophers, and legal theorists has documented in Intervening in the Brain: Changing Psyche and Society. This is one of the most comprehensive empirical and normative discussions to date of the range of issues pertaining to applied neuroscience. A collaborative endeavor led by Reinhard Merkel, Intervening in the Brain shows that the new interventions can have both salutary and deleterious effects on mental states, altering the psyche in unpredictable ways and changing the thought, personality, and behavior that make each person unique. As the authors assert, "Practically no intervention in the structure or functioning of the human brain can be undertaken in complete certainty that it will not affect mental processes, some of which may eventually come to play a key role in a person's self-concept" (p.6).
In addition to a nuanced, balanced assessment of the actual and potential benefits and risks of applied neuroscience, Intervening in the Brain also offers mostly well-reasoned recommendations for which brain-affecting drugs and procedures should or should not be used, and for which individuals. Some of the recommendations are more provocative than others. For example, the authors assert that if a brain-invasive treatment for severe psychopathy became available, then we would not only be permitted but obligated to offer it as an alternative to lifelong incarceration. On the other hand, they believe cognitive enhancement should not be publicly funded because it falls outside the responsibility of health care professionals, which is to prevent and treat disease. In addition, children should never be cognitively enhanced, both because of the potential long-term adverse effects on their developing brains and because it can interfere with their right to an open future.
Despite their objection to public funding of enhancement, the authors argue that there is no justification for prohibiting enhancement in individual cases. Improving one's cognitive capacities should be allowed, provided that individuals pay for cognition-enhancing drugs and take responsibility for any resulting social costs. This position reflects a mature libertarianism, which holds that individuals have the right to do what they want to their brains provided that they do not thereby harm others. Still, what responsibility for these costs would entail for the individual is not clear. The authors say that there is (and should be) a clear distinction between treatment and enhancement at the macro level of health resource allocation, and they draw this distinction in terms of functional loss and what it would take to restore normal functioning. But they acknowledge that for some conditions, treatment shades into enhancement. When the boundary between treatment and enhancement is fuzzy, a doctor has a greater obligation to inform a patient of the potential side effects of prescribed drugs than in standard forms of therapy. This view sidesteps claims by some that doctors would be in the position of irresponsibly prescribing drugs for the purpose of enhancement. Yet others might insist that, by definition, enhancement means improving normal traits and thus does not properly fall within the goals of medicine. This objection may not have much force, however, given that many people purchase these drugs from the Internet and not within the doctor-patient relationship.
The discussion of enhancement in this book is particularly timely in the light of a recent survey in Nature indicating widespread use of methylphenidate (Ritalin) and other drugs among students, academics, and researchers to improve concentration and other cognitive functions...