Alzheimer’s disease is the leading cause of dementia (Snowden et al, 2017): a collection of symptoms involving cognitive decline (Snowden et al, 2017). In the early stages of Alzheimer’s disease, loss of language skills is the first notable effect (Szatskloki et al, 2015). Retrogenesis (Reisberg et al, 2002), the current model of neurodegeneration, states that knowledge is lost in reverse to the order that they were acquired – what you learn first, you forget last (Reisberg et al, 2002). However, bilingual research does not support this pattern: the second language is not always the language most affected by the disease, the non-dominant language is (e.g., Gollan et al, 2010; Ivanova et al, 2014).
Furthermore, bilinguals with Alzheimer’s disease perform better on executive function tasks than monolinguals with Alzheimer’s disease (Alladi et al, 2013). Perhaps then, as bilinguals use executive functions more often than monolinguals (Mirpuri, 2022), active bilinguals could use executive functions more often than passive bilinguals, leading to an advantage in executive functioning (Barbu et al, 2018). Perhaps then, the more that certain neurons and synapses are activated, the stronger that they become (Kennedy, 2015). This could predict that: active bilinguals with Alzheimer’s disease experience an executive function advantage over passive bilinguals with Alzheimer’s disease.
If this were evidenced, perhaps a new model of neurodegeneration should be concerned with the frequency of activation: the more that a function is used, the longer that it takes to degenerate it throughout Alzheimer’s disease. This research aims to explore this possibility to further understand patterns of bilingual neurodegeneration.