Cognitive enhancement aims at amplifying or extending the abilities of the mind through internal or external hardware or software. Up until recently only internal software in the form of trained efficient mental algorithms and the general enhancing effects of paper-based information management was available. As cognitive neuroscience has advanced the range of potential internal enhancement treatments have increased (Farah et al. 2004), as well as the availability and power of external hardware/software support.
Genetic enhancement of memory has been reported, based on over expression of a subunit of the NMDA receptor of mice (Tang et al. 1999). The result was mice that showed greater learning, memory retention and recall abilities: the more flexible subunit made the neurons more efficient at learning new information. It also made them more sensitive to certain forms of pain, showing a potentially non-trivial trade-off (Wei et al. 2001). Similarly learning was increased by over expressing a brain growth protein (Routtenberg et al. 2000) or signalling pathway (Wang et al. 2004). Many of these results could conceivably be used to identify drug targets allowing enhancement without genetic modifications. Other experiments have found ways of promoting the growth of more cerebral cortex during foetal development (Chenn 2002, Chenn & Walsh 2002) although these animal models are at present non-viable. Given the known links between genetics, neuromodulation, mood and personality (Reif et al. 2003, Ham et al. 2004) it also appears likely that genetic modifications could influence personality and mood.
The growing understanding of the cognitive effects of neurochemistry has enabled a new generation of cognition enhancing drugs. Cognition enhancing drugs have been studied since the early 80’s, although it has been known far longer that certain stimulants could improve learning. Today we have several families of memory enhancing drugs affecting different aspects of the learning and encoding process. They range from stimulants (Lee & Ma 1995), nutrients and hormones (Martinez & Kesner 1991) over cholinergic agonists (McGaugh & Petrinovic 1995, Levin 1992, Buccafusco et al. 1995) and the piracetam family (Mondadori 1996) to ampakines (Concar 1997, Lynch et al. 1997, Ingvar et al. 1997) and consolidation enhancers (Lynch 2002). It should be noticed that learning enhancement might not just be useful for traditional memory but also for unlearning phobias and addictions (Pittman 2002, Hall 2003), potentially allowing memory modification.
Drugs improving executive function – working memory, attention control – have been harder to achieve but some progress have occurred here too (Mehta 2000, Elliott 1997, Kimberg, D’Esposito & Farah 1997, Turner 2003). Given that these functions are closely linked to what is commonly seen as intelligence, they may be the first step towards true intelligence enhancing drugs. Alertness is another system that can be enhanced. Traditional stimulants have a host of risks and side effects, but new forms of alertness and sleep-regulating drugs such as Modafinil appear to enable high-performance function with little risk of direct side effects and addiction (Teitelman 2001, Myrick et al. 2004). Add to this the control of diurnal rhythms using the natural hormone melatonine (Cardinali et al. 2002), and sleep becomes if not optional at least manageable.
Although the neuropsychology of creativity is not understood at this point, there appears to be ways to stimulate it. One way appears to be a judicious lowering of inhibitions. A study (Norlander & Gustafson 1996) demonstrated how a mild dose of alcohol could improve the result of a creative design process when taken during the “incubation period” when the test subjects presumably let their subconscious mull over the problem. Some case studies of brain damage (Giles 2004, Raloff97) also suggest that a lowering of inhibition can unleash creative abilities. It is not implausible that reversible changes of this type could be achieved through drugs or transcranial magnetic stimulation (Snyder et al. 2004).
A notable form of chemical enhancement is pre- and perinatal enhancement. By giving choline supplementation to pregnant rats the performance of their pups was enhanced, apparently by changes in neural development (Meck, Smith & Williams 1987, Mellott et al. 2004). Given the ready availability of choline such prenatal enhancement may already (inadvertently) take place. Deliberate changes of maternal diet may hence be seen as part of the cognitive enhancement spectrum.
The most dramatic potential internal hardware enhancements are brain-computer interfaces. At present development is rapid both on the hardware side, where multielectrode recordings from more than 300 electrodes permanently implanted in the brain are currently state-of-the art, and on the software side, where computers learn to interpret the signals and commands (Nicolelis et al 2003, Carmena et al. 2003, Shenoy et al. 2003). Early experiments on humans have shown that it is possible for profoundly paralysed patients to control a computer cursor using just a single electrode (Kennedy & Bakay 1998) and recent experiments by Patil et al. (2004) have demonstrated that the kind of recordings used in monkeys would most likely function in humans too. Cochelar implants are already widely used, and there is ongoing research in artificial retinas (Alteheld et al. 2004) and functional electric stimulation for paralysis treatment (von Wild et al. 2002). While such implants are not currently intended for enhancement purposes (and unlikely to be very desirable for the near future), the digital part of the implant could just as well be connected to any software, enabling various forms of enhancement. Experiments in localised chemical release from implanted chips also suggest the possibility to use neural growth factors to promote patterned local growth and interfacing (Peterman et al. 2004).
While the performance increases from the above forms of enhancement are statistically significant, far greater enhancements can be seen through the use of efficient cognitive strategies, but has often not been discussed in the same terms as biological modifications. Memory arts (Patten 1990) can produce enormous capacity increases in memory of structured information, orders of magnitude greater than the effect of cognition enhancing drugs. Mental training can significantly improve both performance (Nyberg et al. 2003) and long-term health (Barnes et al. 2004). This includes adjustments of arousal levels (Nava et al. 2004), showing the link between emotional modification and cognitive enhancement. Mental training has been used among athletes for a long time (Feltz & Landers 83) and for rehabilitation (Jackson et al. 2004), and may act through re-training parts of the brain used in executing the skill as well as autonomic changes (Decety 1996, Oishi & Maeshima 2004). Such techniques of training-based performance enhancement are widespread and enjoy a broad acceptance in society, but at their core they correspond to deliberate modification of the neural networks of the brain.
Finally, external hardware and software systems can significantly improve effective cognitive power. Wearable computers (Mann 1997) and ubiquitous computing (Weiser 1991) provide intimate contact with the digital world, which in turn can take over a variety of mental tasks: personal organisers, information visualisation, expert systems, symbolic math programs, decision support tools, information searching and various forms of automated agents. As an example, remembrance agents (Rhodes & Starner 1996) act as a vastly extended associative memory. A well-designed environment can enhance proactive memory (Sellen et al.1996). Such systems can both provide new capabilities and amplify existing cognition.
While the fruits of cognition are unfathomably complex, some of the mechanisms producing them are surprisingly simple and amenable to modification or support. It appears likely that within the next 10-20 years we will gain a much deeper understanding of brain development, plasticity and the interplay between the emotional and cognitive systems. This includes the beneficial developmental changes that occur in the brain during enriched rearing. Given the advances in rational drug design, targeted gene therapy and neural interfaces we will have both the tools and the know-how of where to apply them for cognitive enhancement.
Much of the discussion to date of the ethical aspects of cognitive enhancement technologies have focused on five broad areas:
Interventions that affect the next generation, e.g. embryo selection and genetic engineering. Concerns here include the rights and obligations of parents to their children, and to society. Some have argued that genetic selection of this kind would constitute a kind of tyranny of the living over the not-yet-born. There are also questions about the relations of such interventions to the now discredited eugenics programs of the last century. Other interventions that may affect the next generation, such as improvements in maternal nutrition, have not, however, evoked the same concerns: it would be important to determine the reason for this, and to examine whether there are ethically relevant differences between what may appear to be simply various means to the same goal.
The social effects of widespread use of enhancement, particularly the concern that social inequality might be exacerbated by technologically-mediated cognitive enhancements were added to the existing advantages of the wealthy and socially privileged (such as private schooling etc.) In this context, it is necessary to both consider whether future cognitive enhancements would be expensive or relatively cheap (like caffeine), and also to study under what conditions society might have an obligation to ensure universal access to interventions that improve cognitive performance. An analogy might be drawn here to public libraries and basic education.
Whether the use of cognitive enhancement would constitute a form of “cheating”. On some campuses it is now not uncommon for students to take Ritalin or Modafinil when preparing for exams. Does this constitute a form of cheating akin to illicit doping in the Olympics? Or, if save performance enhancers were available, should students rather be encouraged to take them for the same reasons that they are encouraged to take notes, start revising early, etc.?
The appropriateness of using drugs to control behaviour in minors, especially Ritalin and other ADD medications. To what extent do we need to worry that medication becomes a displacement for efforts to confront deeper social or personal problems?
Instrumentalization of human person and of human relations, including broader issues of how the use of issues relating to how medicalizing conditions with the normal human range may reflect a lack of respect for human dignity or a distorted view of the human good.
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