Research articles on language aptitude, both past and recent, nearly without exception start off with a summative definition of the construct itself, declaring that language aptitude is generally considered to be a largely innate and relatively fixed talent that is relatively independent of other internal and external factors. Strangely enough, and as recently pointed out by several researchers (e.g., Chalmers, 2017; Li, 2016; Wen, Biedroń, & Skehan, 2017), this characterization of the nature and origin of language aptitude has rarely been challenged theoretically, let alone investigated empirically. In their overview, Wen, Biedroń, and Skehan (2017) contended that even though research methods have changed significantly in recent years, our knowledge about language aptitude itself “has not developed much at all since it started some 50 years ago,” summarizing that “the concept has remained intact – a relatively fixed trait that is not subject to malleability by later learning experience” (p. 6.). In other words, while empirical research on language aptitude has shifted its focus tremendously during the past 20 years, from the four-componential (black box-like) Carrollian paradigm (e.g., Carroll, 1958, 1962, 1973, 1981; Carroll&Sapon, 1959) to the more open-ended (Pandora’s box-like) “aptitude complexes” framework (e.g., Doughty, 2019; Linck et al., 2013; Robinson, 1997; 2002; Snow, 1994; Sparks et al., 2011), the traditional branding of language aptitude as a largely innate and relatively stable trait has stubbornly persisted. Unfortunately, this persistence not only runs the risk of fueling the already next-to-mystical reputation of language aptitude, but it also seems to have turned the concepts of innateness and stability into an ever-growing elephant in the room. Chalmers (2017) was right in stating that these issues have been grossly neglected, especially in the light of other developments in the field, and we agree with his conclusion that “with new ways of understanding L2 aptitude more holistically [. . .] and some researchers questioning Carroll’s original thinking [. . .], now seems an appropriate time to revisit the issues of stability and untrainability in L2 aptitude” (p. 93).
In this contribution, we explore the question of whether there is reason to maintain the traditional view of language aptitude as a relatively fixed trait that is resistant to experience, or if it should instead be seen as a rather flexible and acquirable skill. We compare the relative experiential effects of (1) having learned an L2 and having been a long-term functional and fluent bilingual in adulthood with (2) having lived with total visual deprivation for a significant period of life. Both bilingualism and visual loss have been reported to have enhancing effects on language-related as well as non-linguistic cognition, but few studies have focused on their effects on language aptitude specifically, especially in the case of blindness. The chapter closes with a discussion on what it would mean for current views on the role of age of L2 acquisition and critical period(s) if the above-average language aptitude hitherto robustly associated with adult near-native L2 learning should turn out to be nothing but an effect of L2 learning itself.