, or stimuli, across the senses (Spence, 2011; Spence and Deroy, 2013). For example, one of the best known correspondences between sound and shape is the Bouba–Kiki effect. People tend to associate the words “Bouba” (soft sound) and “Kiki” (sharp sound) with rounded and angular shapes, respectively (Köhler, 1929; Marks, 1978; Ramachandran and Hubbard, 2001; Bremner et al., 2013). Even though the majority of the research on crossmodal correspondences that has been conducted to date has focused on correspondences between audition and vision (see Parise and Spence, 2013, for a review), there is also a growing interest in examining and documenting other crossmodal correspondences across different senses (see Spence and Deroy, 2014, for a review).
Spence (2011) distinguished between three different types of crossmodal correspondences, including, (1) structural correspondences which are thought to result from commonalities in the way in which different kinds of sensory information are coded neurally, (2) statistical correspondences, which pick-up on the repeated co-exposure of pairs of stimuli or correlated dimensions of experience in daily life, and (3) the linguistic correspondences that are rooted in language. Both statistical and linguistic correspondences may depend on people’s cultural background and on context, thus leading to possible cross-cultural differences. What is more, a fourth type of crossmodal correspondence might be based on an individual’s affective response to stimuli that they want to pair together (Deroy et al., 2013; Palmer et al., 2013). Yet, it should be noted that the different types of correspondences are not mutually exclusive. For example, people may learn the statistical regularities and develop semantic and/or structural correspondences over the short or long term (e.g., Ernst, 2007; Parise and Spence, 2013).
Previous studies have revealed that people match basic tastes with a host of other non-gustatory stimuli/dimensions, such as colors (see Spence et al., 2010, for a review), and shapes (Deroy and Valentin, 2011; Spence and Gallace, 2011; Spence, 2012; Spence and Ngo, 2012; Spence and Deroy, 2014). Given the profound cultural differences in terms of people’s food preferences and consumption behaviors (e.g., Kittler and Sucher, 2007), it would seem reasonable to expect that there would also be significant cross-cultural differences in the visual-taste/flavor associations they express (cf. Bremner et al., 2013). As a case in point, a growing number of studies have recently started to examine cross-cultural differences in the way in which people match gustatory with non-gustatory information, and investigated color–odor associations (e.g., Levitan et al., 2014), color–flavor associations (e.g., Shankar et al., 2010; Velasco et al., 2014; Wan et al., 2014, 2015), and shape-flavor associations (Bremner et al., 2013; Woods et al., 2013). For example, Western participants associate carbonated water with angular shapes, and still water with rounded shapes (Gallace et al., 2011; Ngo et al., 2012), whereas members of the Himba tribe from rural Namibia do not show any such effect (Bremner et al., 2013). Or, to take another example, when asked to match shapes with chocolate having 30, 70, or 90% cocoa content, Westerners tend to associate flavors that are more bitter with more angular shapes (Ngo et al., 2011), whereas the Himba showed the opposite pattern or results, aligning less bitter flavor with more angular shapes (Bremner et al., 2013).
However, a range of cross-cultural similarities have also been documented (e.g., Piqueras-Fiszman et al., 2012; Ngo et al., 2013; Wan et al., 2015). For example, Ngo et al. (2013) assessed crossmodal correspondences between the taste/flavor of fruit juices and various visual attributes in two different cultures. British and Colombian participants were found to associate sweeter fruit juices with rounder shapes while associating sourer-tasting fruit juices with more angular abstract shapes instead. It would seem likely that future research would reveal both culture-