ethics of neuroenhancement: a phantom debate. [book review ...€¦ · enhancement, biological and...
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Year: 2010
Ethics of neuroenhancement: a phantom debate. [Book reviewof: Bettina Schöne-Seifert, Davinia Talbot, Uwe Opolka andJohann S Ach (eds.), Neuro-Enhancement. Ethik vor neuen
Herausforderungen, Paderborn: mentis, 2009]
Quednow, B B
Quednow, B B (2010). Ethics of neuroenhancement: a phantom debate. [Book review of: Bettina Schöne-Seifert,Davinia Talbot, Uwe Opolka and Johann S Ach (eds.), Neuro-Enhancement. Ethik vor neuen Herausforderungen,Paderborn: mentis, 2009]. BioSocieties, 5(1):153-156.Postprint available at:http://www.zora.uzh.ch
Posted at the Zurich Open Repository and Archive, University of Zurich.http://www.zora.uzh.ch
Originally published at:BioSocieties 2010, 5(1):153-156.
Quednow, B B (2010). Ethics of neuroenhancement: a phantom debate. [Book review of: Bettina Schöne-Seifert,Davinia Talbot, Uwe Opolka and Johann S Ach (eds.), Neuro-Enhancement. Ethik vor neuen Herausforderungen,Paderborn: mentis, 2009]. BioSocieties, 5(1):153-156.Postprint available at:http://www.zora.uzh.ch
Posted at the Zurich Open Repository and Archive, University of Zurich.http://www.zora.uzh.ch
Originally published at:BioSocieties 2010, 5(1):153-156.
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Review of Bettina Schöne-Seifert, Davinia Talbot, Uwe Opolka, and Johann S. Ach
(eds.), Neuro-Enhancement. Ethik vor neuen Herausforderungen, Paderborn: mentis,
2009.
Ethics of neuroenhancement: a phantom debate
Boris B. Quednow
University Hospital of Psychiatry,
Division of Experimental and Clinical Pharmacopsychology,
Lenggstr. 31, CH-8032 Zürich, Switzerland
E-mail: [email protected]
With their book Neuro-Enhancement: Ethik vor neuen Herausforderungen, the editors Bettina
Schöne-Seifert, Davinia Talbot, Uwe Opolka, and Johann S. Ach have delivered a collection
of articles providing a cross-section of the ongoing debate over cognitive and mood
enhancement in Germany. As a pharmacopsychologist working on the neurochemistry of
cognition and emotion I have followed this debate for several years now and I have felt
uneasy about it from the start. What follows might rather be a perspectival response to the
presented volume than a classical book review. But considering the current proliferation of
publications on the ethics of neuroenhancement it seems about time to call into question some
of the pharmacological and epidemiological presumptions on which this emergent body of
literature – including the book at hand – is based.
The volume Neuro-Enhancement was developed from papers presented at a one-week
conference organized by the editors at the Hanse-Wissenschaftskolleg in Delmenhorst,
Germany in 2005. All contributors are established experts in the field of medical ethics, but
they come from different disciplines such as philosophy, political science, and medicine. The
chapters are divided into four thematic sections. The first provides a conceptual framework
distinguishing neuroenhancement of healthy subjects from the medical treatment of patients.
Here, Saskia Nagel and Achim Stephan, for example, draw a normative map of conceivable
enhancement options. And Joel Anderson discusses whether the use of imaginable future
neuroprotheses providing music lovers with super hearing would be ethically legitimate. The
second section illustrates the problems and chances of cognitive enhancement in particular.
For instance, Sabine Müller poses the question whether, from idealist and utilitarian
perspectives respectively, the enhancement of intelligence would be morally obligatory – if it
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became possible. The third section reviews issues of emotional enhancement addressing the
challenge posed by drugs such as Prozac to authenticity. And the final section discusses the
ethical implications of neuroenhancement for society at large. As most of the preceding
contributions, Bernward Gesang’s consideration of the social risks and benefits of different
kinds of enhancement or Petra Schaper-Rinkel’s discussion of the political consequences of
thinkable further developments of neuroimplants connecting people in new ways presuppose
that, as the editors put it, neuroenhancement “will actually turn out to be efficient, agreeable
and therefore, from an individual perspective, attractive.”
From a pharmacological point of view, however, this presupposition is questionable.
In my discussion, I will focus on what the book has to say about the enhancement of cognitive
performance (although similar critiques could be developed with respect to emotional
enhancement, biological and technical brain implants, and genetic manipulations). I will not
engage with the ethical, social, and political consequences of enhancement discussed by the
authors (as one could usually expect from a book review) as I believe that already their
pharmacological and epidemiological premises are unrealistic.
Almost all contributions to the volume Neuro-Enhancement are based on the
assumption that, in the near future, we will have access to compounds that are not only
effective cognitive enhancers, but also safe and well-tolerated and therefore suitable to be
taken by everybody (see, for example, the essays of Schaper-Rinkel and Synofzik). This,
however, is not likely to happen in the foreseeable future. It seems that many medical ethicists
have been led astray by exaggerated promises of neuroscientists who are either collaborators
of the pharmaceutical industry or forced to overstate their own results to get increasingly
competitive research funding. As a matter of fact, we are currently even unable to fully restore
disturbed intellectual functioning in psychiatric or neurological diseases and we still do not
know how to achieve this goal in the future.
Let me briefly sum up where we currently stand with respect to cognitive
enhancement. In the discussed book, two drugs are repeatedly referred to as supposedly
effective cognitive enhancers: methylphenidate (Ritalin©, Concerta©), and modafinil
(Provigil ©, Vigil©). Together with amphetamine and the illegal drug cocaine, these
substances share some neurochemical mechanisms and psychotropic effects which justify
calling all of them stimulants. These drugs are affecting the dopamine and noradrenaline
systems and their main effects are an increase of vigilance, arousal, and motivation. But, as
far as we currently know, they have no direct effect on specific cognitive domains such as
memory or executive functions (de Jongh et al., 2008). Thus, stimulants are rather second-
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order cognitive enhancers. For the sake of clarity, they would better be called vigilance or
motivation enhancers. Interestingly, for all of these substances it has been shown that they
increase cognitive performance only in subjects with low baseline capacities whereas in
subjects with higher baseline performance often deteriorates (Mattay et al., 2000; Mattay et
al., 2003; Mehta et al., 2000; Muller et al., 2004; Randall et al., 2005). This points to a
principle brain mechanism that can be found in several neuronal systems and circuits: the
inverse U-function. According to this principle, enhancement is only possible as long as we
do not have an optimal level of arousal, vigilance, or neurotransmitter concentration (Arnsten
& Li, 2005; Kahneman, 1973; Mattay et al., 2003). Hence, an already optimally tuned brain
can hardly be enhanced. Given that usually our brains already perform to the best of their
ability and that the homeostasis of this organ is very sensitive, general enhancement for
everyone seems strictly limited. Against this background, it is not surprising that stimulants –
and here in particular modafinil – are effective to counter cognitive decline caused by sleep
deprivation. It was shown that caffeine – a well-known and effective vigilance enhancer with
tolerable side effects – was about as effective as modafinil to antagonize sleep deprivation-
induced impairments, for example, of reaction time (Killgore et al., 2008; Wesensten et al.,
2002). However, cognitive effects in well-rested healthy subjects are small and hard to detect
(for review see Kumar, 2008).
Moreover, several studies have shown that an increased performance in one cognitive
domain often goes along with a decrease in performance in another domain. For example, we
could enhance our working memory but simultaneously decrease our long-term memory or
vice versa but we will never be able enhance both simultaneously (de Jongh et al., 2008). The
same is true regarding focusing vs. shifting attention and several other cognitive functions.
These phenomena are further complicated by the fact that effects vary between individuals (a
drug may enhance domain X and impair domain Y in individual A, whereas in subject B
domain X is impaired and domain Y is enhanced) (Clatworthy et al., 2009).
Because of the vast complexity of the brain, it seems likely that we will not be able to
overcome trade-offs between enhancement and simultaneous impairment by drugs. Apart
from the collateral adverse effects on cognitive functions, the available substances have many
psychiatric and somatic side effects which make them not well suited for use in healthy
humans only for the purpose of enhancing vigilance or motivation. For example, all
stimulants bear a risk of addiction, which can be explained by their specific mechanism of
action (Berridge, 2007). Thus, I trust in the old pharmacological principle that there is no
effect without a side effect, which is essentially true for all drugs acting on the brain. Our
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brain is of such complexity and its neurotransmitter systems are so strongly interlaced that
turning a small screw in one system generates unpredictable effects in all other systems with
corresponding consequences for behavior. Neuroscience has just scratched the surface of a
still undiscovered universe.
As we have seen there is no genuine cognitive enhancer available to date. There are
several current attempts to develop more specifically acting compounds such as memory
enhancers. However, none of the drugs tested so far have shown replicable and significant
effects in healthy human volunteers (de Jongh et al., 2008; Lanni et al., 2008). Thus, we are
still waiting for an effective drug that enhances cognition at least in patients suffering from
mental dysfunctions. But it seems dubitable whether we will ever see the arrival of drugs
significantly improving cognition in healthy subjects as presupposed in many contributions to
Neuro-Enhancement. Certainly not in the near future.
However, the topicality of the book is not only based on such futurology, but also on
an – equally questionable – diagnosis of the present. In their introduction, Schöne-Seifert and
Talbot argue that already available cognitive enhancers such as methylphenidate and
modafinil are increasingly prescribed beyond their actual indications. They convey a sense of
urgency: “More and more students, professors, and managers are already taking drugs for
neuroenhancement purposes.“ Schaper-Rinkel believes that a market for neuroenhancement is
developing and that its commercial significance will strongly increase in the near future (p.
299).
There is nothing new about such recreational and off-label use of stimulants. From the
1940s to the 1960s, there was an epidemic abuse of amphetamines in countries like the USA,
Great Britain, or Sweden with millions of users. In 1969, shortly before the distribution of
amphetamines was legally restricted, the estimated prevalence of stimulant misuse in the US
was comparable to 2002 (Rasmussen, 2008). Although, at the time, most amphetamines were
sold as mild antidepressants they were also advertised for the enhancement of “mental
alertness” (Rasmussen, 2008). Thus, the supposed urgency of the situation is not due to the
fact that we are facing an unprecedented epidemic.
In fact, the extent of cognitive enhancer abuse today has often been exaggerated (see
the essay of Talbot, p. 325). A frequently cited study reported that up to 13% of high school
students and up to 20% of college students in the US tried methylphenidate (Kapner, 2003).
However, a more recent meta-analysis has shown that the one-year prevalence of experiences
with stimulant cognitive enhancers is only 4% while the lifetime prevalence is 7% (Sussman
et al., 2006). Moreover, the misuse was most prevalent among white male college students
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struggling with their grades and living in larger urban areas (McCabe et al., 2005). These
youth also tend to use illegal drugs such as cannabis, alcohol, MDMA, and cocaine (Sussman
et al., 2006). Interestingly, more than 40% of the students reported that they use
methylphenidate and amphetamine not only for performance enhancement but also to improve
their mood, to get “high”, or for going clubbing (Sussman et al., 2006; Teter et al., 2005). The
misuse of prescription stimulants is highest between 19 and 24 years and then decreases with
increasing age (Johnston et al., 2005). And, finally, the lifetime prevalence of
methylphenidate use in US college students seems to be decreasing rather than increasing,
dropping from 5.7% in 2002 to 3.9% in 2006 (Kapner, 2008). In Germany, in a recent survey
of a big health insurance program, less than 1% of the employees reported that they had used
stimulants at least once in their lives against tiredness and sleepiness (0.93%) or for better
concentration (0.63%) (DAK, 2009). These numbers show that the diagnosed epidemic of
cognitive enhancer abuse is inexistent.
A further result of several surveys was that women prefer the use of antidepressants or
sedative drugs whereas men are more inclined toward the use of stimulants to enhance their
work performance (e.g., DAK, 2009). This phenomenon points to the fact that not everyone is
equally interested in enhancement of his or her intellectual performance. Apart from gender
differences, I suppose that personality exerts a strong effect on the felt need to enhance
cognitive performance. I would predict that narcissistic and ambitious personalities are
especially prone to the use of cognitive enhancers. Unfortunately, to my knowledge, there is
no study that has investigated the influence of personality on the preference of cognitive
enhancers.
Thus, there is no increasing or epidemic use of cognitive enhancers to date, and it is
unlikely that such a trend will develop given that seemingly only a minority of the population
is interested in regular use. Moreover, as stated above, a large number of potential users will
experience somatic side effects or negative effects on cognition that will result in
discontinuation of use. If the epidemiological account that I am providing is correct, then the
question is whether we are actually facing a problematic serious enough to warrant the large-
scale debate over neuroenhancement to which the discussed volume contributes.
In summary, the book Neuro-Enhancement provides a comprehensive compilation of
articles giving a good overview of the current debate over the ethics of cognitive
enhancement. Let me emphasize that I do not take issue with the philosophical quality of the
contributions. But, from my perspective as a neuroscientist, the debate which is so well
represented by the book is based on dubious assumptions. The participants of this discussion
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often claim that their speculative approach provides us with the unique opportunity to discuss
the ethical consequences of new technologies before they are fully developed. At least this
one time, ethics could be ahead of technology. However, do we really need a debate on a
technology that will probably never materialize?
Boris B. Quednow is assistant professor of Experimental and Clinical Pharmacopsychology
at the University Hospital of Psychiatry in Zurich. His main research interests are the
neurotoxicology of illegal drug use as well as the neurochemistry of cognition and disturbed
information processing in psychiatric diseases.
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