The word for left-handed in Latin is sinistra, which translates to English as “sinister.” Romans, among other ancient cultures, believed that being left-handed was a mark of evil. Those who preferred their left hand weren’t trusted and often had to hide their natural preference. Thankfully, modern day lefties don’t (or certainly shouldn’t) experience this kind of persecution. However, our left-handed friends remain a minority, and evidence of their status can be seen all around us; try to find left-handed school desks, pencil sharpeners or scissors – you’ll have to look high and low. While left-handed discrimination seems completely silly to us today, let’s not forget that all forms of discrimination are equally silly. But how does this ancient anecdote relate to toddler language development research?
Intricacies of The Brain
The descending motor pathways of the brain have crossed nerve origins, and as such the right hand is controlled by the left hemisphere of the brain, while the left hand is controlled by the right hemisphere. Similarly, speech and language centers are located in the left hemisphere for the majority of people; this holds true for 97% of right-handed people and roughly 19% of left-handed people, while 68% of lefties also have language abilities in both hemispheres. A variety of research has looked at handedness in relation to language and speech, usually approaching their questions by comparing hand use for physical actions (manipulation) with hand use for communicative actions (gestures). Generally, past research has shown mixed results: previous studies to what will be discussed in this article found that hand preference for manipulation and gestures are only loosely connected.
Toddler Language Development
A 2014 study approached the question with a longitudinal research method – the researchers observed the same children over an extended period of time in attempts to find a more nuanced and enlightening answer to the question of toddler language development. The researchers investigated whether the timing of hand preference for manipulative actions in infancy is related to language skills displayed as a toddler. They hypothesized that early hemispheric specialization in motor skills (consistent infant hand preference) is related to toddler language skills. They predicted that infants who displayed consistent right-handedness would have higher toddler language scores than children with no consistent infant hand preferences.
The study provided evidence that timing is important when it comes to hand preference. Early and consistent right-handedness in infants was related to advanced language ability at toddler age (2 years old), and they scored particularly higher than late developed left-handers. However, they didn’t find a difference in early right-handers and late right-handers. Late right-handers and late-left handers also displayed similar language skills at toddler age. The researchers suspect that the advanced language skills observed in early right-handers was due to greater activity in the left hemisphere areas associated with language (the Broca’s area and Wernicke’s area).
Sinister? Not Quite
The present research does help to shed some light on toddler language development. While the researchers did find advantages in toddler language skills for early developed right-handers over late developed left-handers, this isn’t to say that lefties will be less skilled in language throughout life. These conclusions provide some support for how you should interact and teach your child in their toddler years. Pay special attention to their hand preferences for gesturing and for physical object manipulation. If your child displays early preference for their right hand, you should consider pressing their language development further through more abstract questions or verbal interactions. If they don’t display a preference, then treat them how a child their age should be treated – remember, the research didn’t find the groups other than early right-handers to be in language deficit, but rather at completely normal levels for their age. So, while there may be some differences in toddler language skills between lefties and righties, sinister certainly isn’t the way to describe it.
Title: Developmental Psychology
Publisher: American Psychological Association
Article Type: Article in a Scientific Journal
Impact Factor: 4.141
Sample Size: 38 children
Study Design: The researchers assessed handedness in children at monthly intervals from 6-14 months and again from 18-24 months. They then assessed advanced language skills at 24 months.
http://webspace.ship.edu/cgboer/speechbrain.html (For the percentages of language locations in the brain)