The 1451 Review (Volume 1) 2021

gender has on sustainable purchasing behaviours. Older adults, both male and
female, could also be included.
Moreover, although the main task itself was able to measure the extent to
which the sustainability bias played a role in consumers purchasing behaviours,
in real-life situations consumers are presented with much more information.
When purchasing a clothing item, many other factors are affecting the decisionmaking
process such as brand (Philiastides and Ratcliff 2013) as well as price,
style, fit, and fashion (Butler and Francis 1997). Henceforth, future studies should
take into consideration other attributes of the clothing items that could impact
the decision-making process. Accordingly, participants could be presented with
a similar experiment, but other product attributes could be added and combined
appropriately (e.g. brand, quality, price, etc.). This way, the importance of
sustainability in a real-life situation could be better understood and compared
with the importance that is given to other attributes.
When studying various attributes, it would be key not to only isolate each
of the product attributes, but also to evaluate how consumer choices are
eventually based on the combination of weighting the values of all the attributes
together. This could be accurately measured using non-invasive neuroimaging
techniques (Basten et al. 2010; Gluth et al. 2012). For these reasons, it would be
interesting to use electroencephalography (EEG) or functional magnetic
resonance imaging (fMRI), to comprehend what is happening in the brain when
the decision-making process is taking place. Being able to map the brain areas
involved in these preference-based decisions could even clarify whether
sustainability alters early sensory representations in the brain, later decisionrelated
processing, or a combination of both.
Brain Areas Involved
The binary-value-based decisions that our participants faced involved a
comparison process between items’ values whereby the relative evidence (the
difference in values) was accumulated over time to a decision boundary
representing the selected item.
When making these decisions, the human brain may have emphasized the
process of distinguishing between in-group and out-group membership. It should
be noted that sustainably produced items could have been considered as in-group
items because participants reported caring about sustainability. In‐group has
been defined as a structure of interpersonal relationships or as a depersonalized
social category (Mamat et al. 2014). This emphasis on in-group membership may
have happened at a preconscious level, and that is when the sustainability bias
played a role. Based on the source, the neural systems within the cortex (medial
and lateral prefrontal cortex) could have filtered the information that participants
encountered (Ochsner et al. 2005) placing a higher value on the information from
the in‐group or the sustainable item. The prefrontal’s cortex (PFC) has long been
suspected to play a crucial role in cognitive control, in the ability to coordinate
thought and action according to one’s internal goals (Miller & Cohen 2001).
During the preference-based decisions, the ventromedial prefrontal cortex
(vmPFC) may have also suffered an increase in activity as this region is
responsible for computing the subjective value across different modalities
(Plassmann et al. 2007; Rangel et al. 2008; Bartra et al. 2013; Rangel 2013;
Clithero and Rangel 2014). As such, the different qualities of an item need to be
integrated to construct a valuation signal (Smith et al. 2014), so that the vmPFC
can later compare the various choices by weighting the different values attributed
to each item (Rangel 2013). A previous study also found that the vmPFC is a
critical arbitrator between rewards and adaptive decision-making (FitzGerald et
al. 2012), something that might have happened as participants made more and
more decisions.
Another brain region that may have impacted the decision process is the
orbitofrontal cortex (OFC). The OFT is responsible for encoding the value of an
outcome, monitoring behaviours, and ensuring a socially appropriate behaviour.
Evidence supporting this comes from patients with damage to the OFT, who
despite having intact cognitive abilities, have impaired abilities when making
everyday decisions (Wallis 2007; Funayama and Mimura 2012). For instance, a
patient with OFT damage spent hours deciding where to go for dinner as he took
hours looking at the menu options, the restaurant’s tables, the atmosphere, etc.
Patients with OFC damage struggle when integrating multiple attributes that are
crucial to making a decision (Fellows and Farah 2005). In effect, patients lose the
capability of deciding by their gut feelings (Wallis 2007). In our experiment, the
OFT may have encoded the value for both outcomes: the sustainable item and the
non-sustainable item. Afterwards, despite the sustainable option being the less
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