called language attrition. It has been documented that, under certain conditions, individuals may lose their L1 language proficiency completely, after switching to the exclusive use of another language, and effectively "become native" in a language that was once secondary after the L1 undergoes total attrition. This is most commonly seen among immigrant communities and has been the subject of substantial academic study. The most important factor in spontaneous, total L1 loss appears to be age; in the absence of neurological dysfunction or injury, only young children typically are at risk of forgetting their native language and switching to a new one. Once they pass an age that seems to correlate closely with the critical period, around the age of 12, total loss of a native language is not typical, although it is still possible for speakers to experience diminished expressive capacity if the language is never practiced. Cognitive ability People who use more than one language have been reported to be more adept at language learning compared to monolinguals. Individuals who are highly proficient in two or more languages have been reported to have enhanced executive functions, such as inhibitory control or cognitive flexibility, or even have reduced-risk for dementia. More recently, however, this claim has come under strong criticism with repeated failures to replicate. One possible reason for this discrepancy is that bilingualism is rich and diverse; bilingualism can take different forms according to the context and geographic location in which it is studied. Yet, many prior studies do not reliably quantify samples of bilinguals under investigation. An emerging perspective is that studies on bilingual and multilingual cognitive abilities need to account for validated and granular quantifications of language experience in order to identify boundary conditions of possible cognitive effects. Auditory ability Bilingual and multilingual individuals are shown to have superior auditory processing abilities compared to monolingual individuals. Several investigations have compared auditory processing abilities of monolingual and bilingual individuals using tasks such as gap detection, temporal ordering, pitch pattern recognition etc. In general, results of studies have reported superior performance among bilingual and multilingual individuals. Further, among bilingual individuals, the level of proficiency in the second language was also reported to have an influence on the auditory processing abilities. Economic benefits Bilinguals might have important labor market advantages over monolingual individuals as bilingual people can carry out duties that monolinguals cannot, such as interacting with customers who only