Using Evolutionary Theory to Enhance the Brain Imaging Paradigm Saad, Gad; Greengross, Gil
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Aberystwyth University Using Evolutionary Theory to Enhance the Brain Imaging Paradigm Saad, Gad; Greengross, Gil Published in: Frontiers in Human Neuroscience DOI: 10.3389/fnhum.2014.00452 Publication date: 2014 Citation for published version (APA): Saad, G., & Greengross, G. (2014). Using Evolutionary Theory to Enhance the Brain Imaging Paradigm. Frontiers in Human Neuroscience, 8, [452]. https://doi.org/10.3389/fnhum.2014.00452 Document License CC BY General rights Copyright and moral rights for the publications made accessible in the Aberystwyth Research Portal (the Institutional Repository) are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights. • Users may download and print one copy of any publication from the Aberystwyth Research Portal for the purpose of private study or research. • You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the Aberystwyth Research Portal Take down policy If you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. tel: +44 1970 62 2400 email: [email protected] Download date: 29. Sep. 2021 OPINION ARTICLE published: 20 June 2014 HUMAN NEUROSCIENCE doi: 10.3389/fnhum.2014.00452 Using evolutionary theory to enhance the brain imaging paradigm Gad Saad* and Gil Greengross Marketing Department, John Molson School of Business, Concordia University, Montreal, QC, Canada *Correspondence: [email protected] Edited by: Nick Lee, Loughborough University, UK Reviewed by: Carl Senior, Aston University, UK Keywords: neuroimaging, evolutionary psychology, illusion of explanatory depth, scientific method, ecological validity, domain-specific modules, proximate vs. ultimate In recent years, there seems to be no thought processes. There is a prevailing subjects are physically constrained within preference, choice, emotion, thought, or view that by looking at individuals’ brain a narrow and claustrophobic device which behavior that has escaped the scrutiny activation patterns, we could unveil their may lead to a selection bias. The contrived of a neuroimaging machine. Scanning latent desires. Ariely and Berns (2010) dis- laboratory environments lack ecological the brain allegedly reveals insights into cuss this premise skeptically, specifically validity and as such it is unclear whether the foundations of morality (Greene in the marketing discipline, where there the neuronal activation patterns would et al., 2001), altruism (Tankersley et al., is a nagging fear that by looking at peo- be the same were participants making 2007), sense of humor (Bartolo et al., ple’s brains, marketers would be able to real and consequential choices. To make 2006) and even religious beliefs and God predict individuals’ penchants for certain an actual moral choice in real life dif- (Kapogiannis et al., 2009), to name just a products, future acquisitions and needs, fers from having to imagine making a few of the disparate topics that have been and hence manipulate customers to take hypothetical one whilst lying down in a studied. As neuroimaging studies become advantage of those desires. machine. Brain scans are also quite costly increasingly popular, a growing number This fear is probably unwarranted and and thus sample sizes are typically quite of researchers in the business disciplines stems from what Rozenblit and Keil (2002) small, yielding low statistical power, a are applying such techniques within their describe as “the illusion of explanatory possible overestimation of effects sizes, areas of interest. In such works, researchers depth,” namely to exhibit overconfidence or the failure to detect true effects when look at and map the parts of the brain that in one’s ability to offer veridical expla- they indeed exist (Button et al., 2013). are involved in processing decisions, pref- nations about natural phenomena when Underpowered studies are hard to replicate erences, and choices. Studies range from one’s true knowledge is tentative at best. and they often lead to selection biases in predicting future sales of popular songs Neuroimaging scholars are especially sus- published results. Such studies can either based on how certain areas in the brain ceptible to such biases. The striking report bogus results or can lead to the file were activated on a sample of individuals colorful brain photos and associated tech- drawer effect (e.g., unpublished positive prior to a song’s release (Berns and Moore, nical jargon have a persuasive effect on resultsthatdidnotreachsignificantlevels 2012), how advertisements using various researchers and lay person alike (McCabe due to small samples). These problems forms of persuasion engage different parts and Castel, 2008; Trout, 2008; Weisberg are relatively easy to fix with more rigor- of the brain (Cook et al., 2011), and how et al., 2008), but this should not blind us to ous study designs that include adequate arbitrary prices of wine alter the reward some of the shortcomings of the paradigm sample sizes and transparency regarding activities in an area of the brain associated including the likelihood of reporting spu- power calculations. with pleasure (Plassmann et al., 2008). rious correlations (Vul et al., 2009)and A more fundamental problem in neu- The modus operandi of most imaging false positives such as the infamous case of roimaging studies is the inability to iden- procedures, such as fMRI, is to track blood the neuronal activation patterns “found” tify the exact area in the brain responsible oxygenation in the brain with the under- in a dead Atlantic salmon (Bennett et al., for a given cognitive process. The brain, lying assumption that as blood flows to 2010).Nextwedetailsomeoftheproblems which consumes roughly 20% of all energy a region, the more neurons are activated in neuroimaging research that need to be in our body, is responsible for monitor- in this area. The idea behind such stud- taken into account, and offer a theoretical ing and managing every human activity, ies is not only to locate the exact area in framework that might be helpful in better and is built in a complex network where the brain where information is processed, interpreting the reaped results. different modules work simultaneously for butalsotohaveinsightsintopeople’strue There are several practical prob- almost any task (see Pinker, 1997). At thoughts and preferences, since individu- lems associated with the neuroimaging any moment, multiple areas are activated als cannot control their brain activity and paradigm. Imaging studies are typically concurrently, and it is not easy to pin- are not always consciously aware of their conducted in artificial settings where point the one region that is responsible Frontiers in Human Neuroscience www.frontiersin.org June 2014 | Volume 8 | Article 452 | 1 Saad and Greengross Brain imaging for a certain thought or desire, if one such purpose, but without recognizing specific consequences for survival (differentiating place even exists. Neuroimaging studies evolutionary mechanisms such as natural, a friend from a foe) and reproduction are adept at illuminating areas in the brain sexual, and kin selection, we cannot fully (avoiding incest with a family member). that are associated with certain behaviors, inferwhytheycametobeinthefirstplace More generally, the ability to recognize thoughts, or preferences, but interpreting (see Senior et al., 2011). human faces is itself adaptive. Using an which functions these areas serve based on A first step toward Darwinizing the evolutionary perspective, researchers have the images is difficult and typically can- brain imaging paradigm would be to make shown that the medial frontal cortex was not be derived directly from such images. greater use of evolutionarily meaning- much more activated when making a deci- Moreover, highlighted areas in the brain ful stimuli and tasks (photos of a juicy sion about whether to trust another per- do not exclude the possibility that other burger or a sexy prospective mate) instead son, but not when interacting with an parts of it are also involved, as these parts of largely relying on abstract domain- avatar (Riedl et al., 2014). Lastly, various may already be activated but not show general stimuli and tasks (playing chess or works have explored neural processes asso- additional activity with the new task (Lee choosing between probabilistic gambles). ciated with the reciprocity module includ- et al., 2012). That said, recent studies have Moreover, using an evolutionary frame- ing identifying specific areas in the brain documented the ability to classify mental work can help generate context-specific that are activated during moral dilem- states, namely to accurately map a men- stimuli that are differentially relevant to mas that require cooperation (Singer et al., tal task with a particular activation pattern various demographic groups. For exam- 2004) and detecting cheaters (Stone et al., (Poldrack et al., 2009). ple, if we wish to examine how sexual 2002). Locating a neuronal activation pattern arousal is expressed in the brain, know- Ultimately, the exploration of evolved in the brain tells us little about the under- ing the evolutionary roots of sexual fan- domain-specific modules (rather than lying causes that led to the cortical activ- tasies