In the 1970s, my early childhood provider advised my immigrant Mexican American mother to stop speaking Spanish with me at home. They were concerned because, as a 2 year old, I was not as verbal as my peers. Worried that she was causing me harm, my mother immediately stopped speaking to me in Spanish.
I was not alone in this experience. Back then, it was a common assumption that exposure to more than one language would confuse young children and could lead to developmental delays (Espinosa, 2008; Tabors, 2008). Research on dual language development has grown substantially since the 1970s. Information on the dual language process and the numerous benefits for young children is now more readily available. My experience and the experience of many other children of immigrants highlight the importance of providing parents with up-to-date, high quality research so they can make the best decisions for their children.
How Do Children Learn a Second Language?
In general, there are two ways in which children may learn a second language: simultaneously or sequentially (McLaughlin et al., 1995; Tabors, 2008).
Simultaneous Second Language Learning
Simultaneous learners include children under the age of 3 who are exposed to two languages at the same time. These children may include those who are exposed to one language by parents at home and another language by providers in their early childhood program. Simultaneous learners are also young children whose parents each speak separate languages to them at home (e.g., mother speaks Spanish to child, father speaks Chinese to child).
Before 6 months of age, simultaneous learners learn both languages at similar rates and do not prefer one language over the other. This is because they build separate but equally strong language systems in their brains for each of the languages they hear. These separate systems allow children to learn more than one language without becoming confused. In fact, the pathways infants develop in their brains for each of the languages they hear are similar to the single pathway developed by children who are only exposed to English.
At 6 months, children begin to notice differences between languages and may begin to prefer the language they hear more. This means that parents must be careful to provide similar amounts of exposure to both languages; otherwise, children may begin to drop vocabulary of the language to which they are less exposed (Espinosa, 2008; Kuhl, 2004; Kuhl et al., 2006; Tabors, 2008).
Cognitive Benefits of Simultaneous Language Development
There are many cognitive benefits for young children who are simultaneously exposed to more than one language. For example, they have greater neural activity and denser tissue in the areas of the brain related to memory, attention, and language than monolingual learners. These indicators are associated with long-term positive cognitive outcomes for children (Bialystok 2001, Mechelli et al., 2004; Kovelman, Baker, & Petitto, 2006).