In the 21st century, new powerful technologies, such as different artificial intelligence (AI) agents, have become omnipresent and the center of public debate. With the increasing fear of AI agents replacing humans, there are discussions about whether individuals should strive to enhance themselves. For instance, the philosophical movement Transhumanism proposes the broad enhancement of human characteristics such as cognitive abilities, personality, and moral values (e.g., Grassie and Hansell 2011; Ranisch and Sorgner 2014). This enhancement should help humans to overcome their natural limitations and to keep up with powerful technologies that are increasingly present in today’s world (see Ranisch and Sorgner 2014).

Not only in science but also among the general population, cognitive enhancement, such as increasing one’s intelligence or working memory capacity, has been a frequently debated topic for many years (see Pauen 2019). Thus, a lot of psychological and neuroscientific research investigated different methods to increase cognitive abilities, but—so far—effective methods for cognitive enhancement are lacking (Jaušovec and Pahor 2017). Nevertheless, multiple different (and partly new) technologies that promise an enhancement of cognition are available to the general public. Transhumanists especially promote the application of brain stimulation techniques, smart drugs, or gene editing for cognitive enhancement (e.g., Bostrom and Sandberg 2009). Importantly, only little is known about the characteristics of individuals who would use such enhancement methods to improve their cognition.

Cognitive enhancement1 describes the enhancement of different cognitive abilities in healthy individuals (Viertbauer and Kögerler 2019). Thus, it needs to be differentiated from compensatory enhancement, which is applied for therapeutic reasons when individuals have certain disabilities or illnesses and need to compensate for those (Birnbacher 2019). For the former (cognitive enhancement), transhumanists advertise different methods—most of which arise from the technological progress in the last decades. Some frequently discussed enhancement methods are, for instance, pharmacological enhancement, current-based enhancement, genetic enhancement, and mind upload (e.g., Bostrom and Sandberg 2009; Loh 2020). 

Pharmacological enhancement describes the intake of certain drugs (e.g., substances based on modafinil, amphetamine, or methylphenidate), not for their prescribed use but to enhance one’s central nervous system (see Repantis et al. 2010). While these drugs are usually used to treat disorders such as attention deficit hyperactivity disorder (Schifano et al. 2022), there seems to be an increase in their use for cognitive enhancement (Esposito et al. 2021; Maier et al. 2018). However, the effectiveness of so-called smart drugs for cognitive enhancement seems rather mixed (e.g., Daubner et al. 2021). Furthermore, their intake might be accompanied by certain risks, such as addiction (Massie et al. 2017; Sharif et al. 2021).

Current-based enhancement entails the application of different brain stimulation techniques, such as transcranial electric or deep brain stimulation. This enhancement method is used to increase cognitive abilities such as working memory (Jaušovec and Pahor 2017; Luber et al. 2007), but findings on the effectiveness of current-based enhancement are mixed so far. For instance, a meta-analysis by Simonsmeier et al. (2018) showed that transcranial electric stimulation had stronger positive effects when applied during learning compared to test performance—but only for anodal and not cathodal stimulation and the effectiveness was dosage-specific. Thus, the effectiveness of current-based enhancement seems to depend on multiple characteristics of the applied stimulation. Due to the increasing availability of current-based enhancement methods, Santarnecchi et al. (2015) argued for guidelines and regulations to ensure users’ safety. This is especially important as it is unclear how the regular use of current-based enhancement might affect one’s brain (e.g., Shah-Basak and Hamilton 2017).

Genetic enhancement might become an especially powerful enhancement method in the future. The possibility of altering human genes allows for the optimization of body and cognition—even before a child is born. Thus, already within the fetus, supposedly undesired characteristics can be modified (which is sometimes also called prenatal and perinatal enhancement; Bostrom and Sandberg 2009). Research has already identified genes relevant to intelligence (Plomin and von Stumm 2018). Thus, in the future, those might be modified to enhance cognition. Such gene editing poses important ethical questions, such as who can decide when modifying the genes of a fetus (see e.g., Bostrom and Sandberg 2009).

Mind upload describes a rather futuristic cognitive enhancement method that is commonly part of science-fiction literature and movies. It refers to the possibility of uploading one’s personality, intelligence, memories, and other characteristics onto an external hard drive so that one can live digitally and forever—independent of one’s body (e.g., Laakasuo et al. 2018). Although this idea seems unrealistic currently, it is frequently debated by transhumanists, and there are even ongoing projects within and outside the European Union that are investigating the potential digitalization of the brain (e.g., the Neurotwin project2).

Working memory training might enhance individuals’ working memory capacity and potentially also their intelligence. For instance, in a study by Jaeggi et al. (2008), working memory training was shown to improve working memory capacity (near-transfer effect) as well as fluid intelligence (far-transfer effect). However, replication studies failed to reproduce the far-transfer effect (Melby-Lervåg and Hulme 2013; Shipstead et al. 2012). Thus, it is questionable whether completing working memory training enhances individuals’ cognition beyond the trained task. Nevertheless, many tools that promise a broad cognitive enhancement via working memory training are available to the general public. For instance, on 19 January 2023, the Google Play Store offered more than 30 apps for “working memory training”.

Game-based enhancement is another form of enhancement that involves improving one’s cognition by playing video games. Studies have shown positive effects of gaming on cognitive abilities (Green and Bavelier 2003; see also Oei and Patterson 2013). Additionally, a study by Ninaus et al. (2015) showed a positive effect of gaming elements on performance and efficiency in working memory tasks. Nevertheless, it is unclear whether the positive effects of playing games on cognition are stable over time or can be transferred to settings outside the gaming context (see Ninaus et al. 2015; Oei and Patterson 2013).

Neurofeedback training is another non-invasive method that aims at training individuals to deliberately control their brain activity. Individuals get visual, auditory, or haptic feedback on their brain activity with, for instance, electroencephalography or functional magnetic resonance imaging. The goal is that individuals learn to increase and decrease certain brain activities (e.g., the sensorimotor rhythm; Kober et al. 2018), which, in return, might foster motor activity, affect, and cognition (Enriquez-Geppert et al. 2017; Kober and Wood 2020). Neurofeedback training is used in clinical settings to, for instance, treat patients after having a stroke (e.g., Kober et al. 2015). For healthy individuals, the first studies also suggest positive effects of neurofeedback training such as on working memory (Kober et al. 2015) or attention (Gruzelier 2014). However, additional research is necessary to systematically test the effectiveness of neurofeedback training as an enhancement method (see Kober and Wood 2020).

Brain-machine interfaces3 describe the connection between a brain and a computer through, for instance, brain implants that allow the control of computers. Through brain-machine interfaces, machines can be controlled by the brain, without manually interacting with them (e.g., Silva 2018). In addition to receiving a brain implant, oftentimes intensive training is required to achieve a connection between the brain and the computer (Silva 2018). Currently, scientists test whether brain-machine interfaces can be used to transfer words (Moses et al. 2019) or to move robotic extremities by the power of thought. A well-known institution working on brain-machine interfaces is Neurolink, led by Elon Musk. Their goal is to use brain-machine interfaces not only for humans with neurological disorders but also to enable a connection between (healthy) humans and artificial intelligence. However, the use of brain-machine interfaces is accompanied by multiple challenges such as the neural resources allocation problem which describes “the channeling of motor commands and sensory information to and from the augmentative device without hindering the motor control of biological limbs” (Dominijanni et al. 2021, p. 851).

The broad application of cognitive enhancement might be accompanied by many societal changes (see Neubauer 2021). For instance, access to enhancement could increase social inequality if wealthy people could afford enhancement more easily than poor people. Furthermore, if enhancement proves to be effective, there might be pressure for individuals to get enhancement by, for instance, their employers. Additionally, if everyone can become smarter, the question arises whether a majority will become academics, leading to a lack of people in blue-collar jobs (see Neubauer 2021). Due to the (ethical) challenges enhancement might raise for society but also due to the potential risks for individuals (e.g., long-term damages or addiction), it is highly important to investigate who wants to enhance themselves while these methods are still being developed. If the characteristics of individuals who want to get enhanced are known, they can be specifically targeted to sensitize them to the correct application of different enhancement methods and inform them about their potential side effects.

So far, psychological research and, especially individual-differences research, investigating factors related to cognitive enhancement is rather absent (see Neubauer 2021). Only a few studies investigated individuals’ assumptions about and acceptance of enhancement up to now (e.g., Breivik et al. 2022; Grinschgl et al. 2022; Mayor et al. 2020; Laakasuo et al. 2018; Schönthaler et al. 2022). For instance, Laakasuo et al. (2018; see also 2021) tested—among other factors—how personality traits, science-fiction hobbyism, and purity norms are related to individuals’ feelings and reactions toward mind upload. Purity norms include values such as pureness, naturalness, and decency. While a higher interest in science-fiction was related to a higher approval of mind upload, stronger purity norms were associated with less approval. Thus, exposure to and familiarity with futuristic ideas such as in science-fiction content seems relevant when it comes to the acceptance of enhancement. Furthermore, the purity of one’s mind and actions might drive the acceptance of enhancement. In the same study, Laakasuo et al. (2018) observed no significant relationships between personality factors and acceptance of mind upload.

Grinschgl et al. (2022) investigated individuals’ assumptions about four different passive enhancement methods. Individuals’ openness was related to more negative assumptions about most enhancement methods. However, the observed effects were only small and no other consistent findings with variables such as basic human values were observed. In another study, Schönthaler et al. (2022) tested the Big Five traits and sub-facets as well as the Dark Triad traits and basic human values as predictors of the acceptance of enhancement. While extraversion, neuroticism, and openness were not related to the acceptance of enhancement, lower agreeableness and conscientiousness were related to more acceptance of cognitive enhancement. This supports the idea that the traits of agreeableness and conscientiousness are related to avoiding risky behaviors (see Schönthaler et al. 2022). In addition, conscientious individuals might view enhancement (and related performance-gains) as unfair and not authentic. With regard to basic human values, lower self-transcendence values but higher self-enhancement values were related to more acceptance of enhancement. Moreover, Schönthaler et al. (2022) observed that the Dark Triad traits (Machiavellianism, psychopathy, and grandiose narcissism) and vulnerable narcissism were positively related to the acceptance of enhancement. Thus, individuals high on Dark Triad traits might be associated with showing ethically questionable behaviors (see e.g., Harrison et al. 2018) such as applying enhancement. In addition, those individuals might view enhancement as a promising strategy to fulfill their self-centered goals (see Schönthaler et al. 2022). Yet, in multiple regression, these dark traits showed no incremental validity beyond the predicting sub-facets of agreeableness and conscientiousness as well as values.

So far, convergent evidence on the predictors of cognitive enhancement is lacking.