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Overstating the Role of Environmental Factors in Success: A Cautionary Note

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Abstract

Several currently popular areas of research—brain training, mindset, grit, deliberate practice, and the bilingual advantage—are premised on the idea that environmental factors are the overwhelming determinants of success in real-world pursuits. Here, we describe the major claims from each of these areas of research, before discussing evidence for these claims, with a particular focus on meta-analyses. We then suggest that overemphasizing the malleability of abilities and other traits can have negative consequences for individuals, science, and society. We conclude with a call for balanced appraisals of the available evidence concerning this issue, to reflect current scientific discrepancies, and thereby enable informed individual decisions and collective policies.
Running head: OVERSTATING ENVIRONMENTAL FACTORS IN SUCCESS
Overstating the Role of Environmental Factors in Success:
A Cautionary Note
Word count: 2,419
Correspondence:
David Moreau
The University of Auckland
Centre for Brain Research
Science Centre
23 Symonds Street, Office 227
Auckland 1010
New Zealand
+64 9 373 7599 ext. 83401
d.moreau@auckland.ac.nz
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OVERSTATING ENVIRONMENTAL FACTORS IN SUCCESS
Overstating the Role of Environmental Factors in Success:
A Cautionary Note
David Moreau
School of Psychology and Centre for Brain Research
The University of Auckland
Brooke N. Macnamara
Department of Psychological Sciences
Case Western Reserve University
David Z. Hambrick
Department of Psychology
Michigan State University
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OVERSTATING ENVIRONMENTAL FACTORS IN SUCCESS
Abstract
Several currently popular areas of research—brain training, mindset, grit, deliberate practice, and
the bilingual advantage—are premised on the idea that environmental factors are the
overwhelming determinants of success in real-world pursuits. Here, we describe the major claims
from each of these areas of research, before discussing evidence for these claims, with a
particular focus on meta-analyses. We then suggest that overemphasizing the malleability of
abilities and other traits can have negative consequences for individuals, science, and society.
We conclude with a call for balanced appraisals of the available evidence concerning this issue,
to reflect current scientific discrepancies, and thereby enable informed individual decisions and
collective policies.
Keywords: abilities, skills, interventions, environment, genetics.
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OVERSTATING ENVIRONMENTAL FACTORS IN SUCCESS
Overstating the Role of Environmental Factors in Success:
A Cautionary Note
I believe that if one always looked at the skies, one would end up with wings.
Gustave Flaubert, Pensées, 1915.
The view that a person’s environment plays a much greater role in determining success in
the world than innate traits has long been a theme of psychological theorizing. Nearly a century
ago, John Watson, the founder of behaviorism, articulated this view when he wrote, “[g]ive me a
dozen healthy infants, well-formed, and my own specified world to bring them up in and I’ll
guarantee to take any one at random and train him to become any type of specialist I might
select—doctor, lawyer, artist, merchant-chief and, yes, even beggar-man and thief, regardless of
his talents…” (Watson, 1930, p. 104). The appealing implication of this view is that anyone can
become highly successful, whether it be in school, work, or a hobby.
While few, if any, contemporary scientists would endorse Watson’s (1930) extreme view,
the idea that individuals’ capabilities are highly malleable, and thus that environmental factors
are the overwhelming determinants of accomplishment in real-world pursuits, remains a
powerful undercurrent in psychological research. Currently, this view is emphasized in five
popular areas of research: brain training, mindset, grit, deliberate practice, and the bilingual
advantage. Thousands of scientific articles have been published on these topics, which have also
captured the popular imagination through books such as Smarter: The new science of building
brain power (Hurley, 2014), Mindset: The new psychology of success (Dweck, 2006), Grit: The
power of passion and perseverance (Duckworth, 2016), and Peak: The new science of expertise
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OVERSTATING ENVIRONMENTAL FACTORS IN SUCCESS
(Ericsson & Pool, 2017). Some of these areas of research have also spawned lucrative
commercial ventures. Brain training is a multibillion-dollar industry, and commercial mindset
interventions are used in schools around the world.
Nevertheless, the central claims of each of these areas of research have been increasingly
called into question in the scientific literature. Here, we briefly summarize evidence from each
area of research, focusing on large-scale studies and meta-analyses. Our intent is not to criticize
individual theorists—misleading statements can find their way to the media and popular beliefs
despite caution expressed by the theorists (see, e.g., Duckworth, 2016). Rather, our goal is to
present current evidence for the claims central to each area of research. We conclude that caution
is warranted when considering both future research on these topics and translations of this
research to real-world applications.
Brain Training
The premise of brain training is that the brain is “like a muscle,” in the sense that it can
be strengthened through cognitive “exercise.” More specifically, the idea is that training in tasks
that target core cognitive functions such as working memory, attention, and spatial ability
generalizes to real-world situations that call on these functions. This claim of far transfer has
been at least implicit in advertising claims by brain training companies (see Simons et al., 2016).
Scientists have made similar claims, arguing that working memory training improves fluid
intelligence (Jaeggi, Buschkuehl, Jonides, & Perrig, 2008) and that videogame playing enhances
visuospatial abilities (Green & Bavelier, 2003).
Nevertheless, after more than a decade of intensive research on brain training, it is clear
that far transfer is elusive. Several meta-analyses have demonstrated that the benefits of brain
training are limited to the trained task, or to very similar tasks (near transfer). For example, a
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meta-analysis by Melby-Lervåg and Hulme (2013), found “no convincing evidence of the
generalization of working memory training to other skills” (p. 270). They also noted that
working memory training studies are often plagued by major methodological problems,
including use of research designs without appropriate control groups. More recently, Simons and
colleagues conducted an exhaustive review of the available evidence for benefits of brain
training and concluded that “the evidence that training with commercial brain-training software
can enhance cognition outside the laboratory is limited and inconsistent” (Simons et al., 2016, p.
173). Finally, in a meta-analysis examining brain training in the form of playing video games,
Sala, Tatlidil, and Gobet (2017) “found no evidence of a causal relationship between playing
video games and enhanced cognitive ability” (p. 111).
Mindset
Whereas the idea of brain training is to directly strengthen cognitive abilities, the aim of
mindset interventions is to increase people’s beliefs that they can be strengthened. Dweck and
colleagues have argued that people who hold a growth mindset believe that intelligence (and
other traits) can be improved with effort (Dweck, 2000), and thus will persist to overcome
obstacles and work hard; by contrast, people with a fixed mindset believe intelligence is
relatively stable and are “devastated by setbacks” (Dweck, 2008). In a typical mindset
intervention, participants are told that the brain is like a muscle and can grow with effort. As
Dweck (2007) explained, students learn about “how they can make their brains work better and
grow smarter" (p. 38). These brief interventions are touted for “striking effects on educational
achievement” (Yeager & Walton, 2011, p. 268; see also Boaler, 2013; Dweck, 2008).
Mindset interventions are used in schools around the world. However, evidence for the
impact of mindset on real-world outcomes is equivocal. Large-sample research has failed to
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replicate findings of beneficial effects of mindset interventions. As a case in point, across three
studies with a total sample over 600 participants, Li and Bates (2017) found “no support for
mindset-effects on cognitive ability, response to challenge, or educational progress” (p. 2).
Furthermore, in a recent meta-analysis, Sisk, Burgoyne, Sun, Butler, and Macnamara (2018)
examined the effectiveness of growth mindset interventions on academic achievement and
identified a number of methodological shortcomings among mindset studies, such as many
instances of manipulation checks either not being successful or not being reported. Sisk et al.
found that the effectiveness of mindset interventions on academic achievement was very weak
overall, with almost all analyses yielding small or null effects. They concluded that "those
seeking more than modest effects or effects for all students are unlikely to find them" (p. 568).
Grit
Grit refers to perseverance and passion for long-term goals (Duckworth & Eskreis-
Winkler, 2013; Duckworth, Peterson, Matthews, & Kelly, 2007). Gritty people maintain “effort
and interest over years despite failure, adversity, and plateaus in progress” (Duckworth et al.,
2007, p. 1088), whereas less gritty people are easily discouraged (Duckworth & Eskreis-Winkler,
2013). Duckworth (2016) argued that “you can grow your grit” (p. 269), and Duckworth and
Gross (2014) stated they were “optimistic that a better understanding of the psychological
processes underlying self-control and grit could, in fact, lead to high-impact, cost-effective
interventions" (p. 323).
However, in a study of 4,642 twins, Rimfeld, Kovas, Dale, and Plomin (2016) found that
grit was substantially heritable, but found no evidence for a shared environmental influence on
grit. Rimfeld et al. explained that "[t]he most limiting finding, for any possible intervention, is
that shared environmental influence is negligible" (p. 786). In other words, current
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environmental factors such as how parents raise their children or approaches schools take to
teaching do not appear to influence grit. They also noted that, despite a lack of evidence that grit
can be trained, training grit has been established as a priority by the U.S. Department of
Education (see http:// edf.stanford.edu/readings/download-promotings-grit-tenacity-
andperseverance-report) and the U.K. Department of Education (see
https://www.gov.uk/government/news/england-to-become-a-globalleader-of-teaching-character).
Rimfeld et al. (2016) caution, "[t]he effectiveness of training programs should be rigorously
researched before they are rolled out widely" (p. 781).
Evidence further suggests that, even if grit is found to be trainable, it may have no impact
on academic achievement above and beyond other personality factors. For example, Rimfeld et
al. (2016) stated that "[g]rit adds little phenotypically or genetically to the prediction of academic
achievement beyond traditional personality factors, especially conscientiousness" (p. 780).
Similarly, Credé, Tynan, and Harms (2017) conducted a meta-analysis investigating the
influence of grit and other traits on academic achievement, and found that while
conscientiousness explained variance in academic achievement after controlling for grit, "overall
grit explains no variance in either overall academic performance or high school GPA after
controlling for conscientiousness" (p. 501).
Deliberate Practice
The concept of deliberate practice emphasizes the importance of environmental factors in
the context of acquiring expertise in a specific domain. The deliberate practice view claims that
“individual differences in ultimate performance can largely be accounted for by differential
amounts of past and current levels of practice" (Ericsson et al, 1993, p. 392). More generally,
Ericsson (2007) claimed that “it is possible to account for the development of elite performance
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among healthy children without recourse to unique talent (genetic endowment)—excepting the
innate determinants of body size” (p. 4). A further claim of this view is that "it is impossible for
an individual with less accumulated practice at some age to catch up with the best individuals,
who have started earlier and maintain maximal levels of deliberate practice not leading to
exhaustion" (Ericsson et al., 1993, p. 393).
There is no question that deliberate practice can lead to major improvements in
performance within an individual. The controversial claim is that deliberate practice can largely
explain differences in performance across individuals. This claim is not supported by empirical
evidence. In a recent meta-analysis, Macnamara, Hambrick, and Oswald (2014) found that
deliberate practice leaves the majority of variance in performance across individuals unexplained
and potentially explainable by other factors (see also Platz et al., 2014). In another meta-analysis,
Macnamara, Moreau, and Hambrick (2016) found that deliberate practice accounted for a non-
significant 1% of the variance in performance among elite-level athletes, inconsistent with
Ericsson and colleagues’ (1993) claim that “[i]ndividual differences, even among elite
performers, are closely related to assessed amounts of deliberate practice” (p. 363). Furthermore,
Macnamara et al. (2016) found that higher-level athletes were no more likely to have begun
practicing their sport at a younger age than their lower-level counterparts. Together, this
evidence indicates that deliberate practice is not the only important contributor to individual
differences in expertise.
Bilingual Advantage
Finally, there is currently a great deal of scientific interest in the benefits of bilingualism
for cognitive functioning—the so-called bilingual advantage (Bialystok, 1999). The idea behind
the bilingual advantage is that prolonged experience maintaining multiple languages in working
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memory and inhibiting the inactive language(s) improves executive functioning. As Bialystok
(2009) explained, "The effect of bilingualism on cognitive functioning as evidenced by lexical
access, executive control, and working memory, is part of a growing body of research
demonstrating the powerful role of experience on cognitive function and cognitive organization"
(p. 9).
However, multiple researchers have pointed out that the literature on the bilingual
advantage research suffers from a high degree of publication bias, favoring statistically
significant, positive effects (de Bruin, Treccani, & Della Sala, 2015). Indeed, a recent, large-
scale meta-analysis showed no evidence for the bilingual advantage in any executive functioning
domain after correcting for publication bias (Lehtonen et al., 2018). Similarly, in a detailed
critique of the literature, Paap, Johnson, and Sawi (2015) pointed out that over 80% of the tests
assessing the bilingual advantage since 2011 yielded null findings.
What’s the Harm?
The evidence that we have just reviewed notwithstanding, one might argue that there is
no harm in people believing in the overwhelming importance of environmental factors in
success. What, for example, is the harm in leading the elderly to believe that “brain games” will
have broad benefits for cognitive functioning, even if that is unlikely given the available
evidence? Or what is the harm in enrolling children in mindset interventions (touted as relatively
inexpensive), even if the available evidence casts serious doubt on the effectiveness of these
interventions?
We think there is potential harm in the form of opportunity costs. Some of these
opportunity costs impact society. For example, time that students spend completing ineffective
interventions could be spent on learning mathematics, science, language, arts, and other school
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subjects. Similarly, money spent on brain training or mindset programs for a school—even if the
program is cheaper than other interventions—could be spent on more effective interventions or
on needs such as hiring additional teachers. Other opportunity costs impact science. For example,
at the cost of pursuing other areas of research, young scientists excited about these topics might
dedicate their formative training years to pursuing effects that they are unlikely to find. Likewise,
researchers spending time and effort attempting to reproduce, validate, or meta-analyze these
claims do so at the expense of pursuing other research endeavors. Finally, funding dedicated to
these areas could go to more promising areas.
We further argue that overemphasizing the role of environmental factors in success may
lead to failure being stigmatized, despite the fact that individual differences in many real-world
endeavors may in part reflect factors that are not under people’s control. That is, by
overemphasizing the influence of environmental factors, we may unintentionally hold
individuals accountable for conditions, events, or outcomes beyond their control, including
learning disabilities and neurological disorders. If, for example, the brain is “like a muscle” and
cognitive functions can be dramatically increased through brain training, then why should any
child suffer from learning disabilities or ADHD? Likewise, if deliberate practice is the
overwhelming determinant of expertise, why should anyone who devotes thousands of hours of
practice to a given sport not become an Olympic gold medalist? In short, we argue that
overemphasizing malleability while minimizing the role of stable traits in success may burden
individuals and families with responsibilities that are largely not theirs to bear.
Conclusion
There is no doubt that environmental factors play an important role in determining
success in real-world domains. At the same time, it now seems clear that environmental factors
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have a more limited impact on individual differences in success than some theories suggest.
Views that emphasize malleability over the influence of stable traits on success are appealing,
particularly in modern, democratic societies, which place great emphasis on equal opportunities
across individuals. However, acknowledging the role of factors that are difficult to change is
important, because it enables the allocation of resources where they can have a real impact,
taking into account individual needs, to allow meaningful improvements.
In our view, continuing to accept claims that are unsupported by evidence hinders
scientific progress and prevents evidence-based policies. The scientific community should
therefore consider current evidence and direct research toward endeavors that provide insight on
the complex and interacting factors that contribute to individual differences in success in real-
world domains. Ultimately, recognizing and understanding individual differences, rather than
denying or undermining their importance, leads to politics of equity—providing individuals with
the means to thrive—rather than equality—treating everyone uniformly regardless of their
specific needs.
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Recommended Readings
Simons, D. J., Boot, W. R., Charness, N., Gathercole, S. E., Chabris, C. F., Hambrick, D.
Z., & Stine-Morrow, E. A. L. (2016). Do “Brain-Training” Programs Work? Psychological
Science in the Public Interest: A Journal of the American Psychological Society, 17(3), 103–
186. http://doi.org/10.1177/1529100616661983
This paper reviews evidence for the efficacy of brain training programs, and provides a
set of guidelines and best practices the design and reporting of interventions.
Sisk, V., Burgoyne, A., Sun, J., Butler, J., & Macnamara, B. N. (2018). To What Extent
and Under Which Circumstances Are Growth Mindsets Important to Academic Achievement?
Two Meta-analyses. Psychological Science, 29(4), 549-571.
This paper reports on two meta-analyses exploring the relationship between mindset and
academic achievement as well as the efficacy of growth mindset interventions in schools.
Credé, M., Tynan, M. C., & Harms, P. D. (2017). Much ado about grit: A meta-analytic
synthesis of the grit literature. Journal of Personality and Social Psychology, 113(3), 492–511.
http://doi.org/10.1037/pspp0000102
This paper presents a meta-analytic synthesis of the grit literature, with a particular
focus on the relation between grit, cognitive ability and performance.
Ullén, F., Hambrick, D. Z., & Mosing, M. A. (2016). Rethinking expertise: A
multifactorial gene–environment interaction model of expert performance. Psychological
Bulletin, 142(4), 427-446. http://dx.doi.org/10.1037/bul0000033
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This paper proposes a multifactorial gene– environment interaction model of expertise as
an alternative to the deliberate practice framework.
Paap, K. R., & Greenberg, Z. I. (2013). There is no coherent evidence for a bilingual
advantage in executive processing. Cognitive Psychology, 66(2), 232–258.
This paper reviews the evidence for a bilingual advantage in executive processing,
together with a set of three experimental studies investigating the effect via a comparison of
bilingual and monolingual populations.
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