This includes activities like writing, cutting, and catching and throwing a ball. The dominant hand is not really a choice because it is not a conscious decision that we make as children. Genetics and the individual's brain play a role in which will be the dominant hand. Parents should be cautioned about trying to switch their child from one dominant hand to another.
You should also try not to worry if your child does not develop a hand preference by a certain age. Allow nature to take its course and talk to your child's teacher or doctor if you do have any concerns. Some children discover their dominant hand very early.
Infants develop unilateral manipulation skills—the ability to use one hand—at 7 to 9 months of age, but it is not until 10 to 11 months that they develop a true consistent hand preference. The majority of the time, hand dominance in children children begin to stabilize around 18 months to 2 years of age. For some kids, it may not be until they reach the ages of 4 or 6. When children begin learning to write in school, their teacher may note that they have not yet chosen a dominant hand.
Some never do and will be ambidextrous or mixed-handed. When it comes to hand dominance, there are three types. Learn more about each type below. Though hand dominance means tasks are performed more efficiently by the dominant hand, the non-dominant hand also plays a significant role in completing tasks. This is known as bilateral-coordination and is important in many important tasks. For instance, when you're typing on the computer, both hands are working together.
Get diet and wellness tips to help your kids stay healthy and happy. Genome-wide association study of handedness excludes simple genetic models. Many functions of the brain — such as language, memory, attention, emotional processing, and face perception — are specialized on one side of the brain. Handedness has long been linked to language lateralization. In the majority of right-handed individuals, language dominance is on the left side of the brain. But while common myth may have us believe that in left-handed individuals the sides are switched, only a quarter show language dominance on the right side of the brain.
Today, there is a broader understanding of hand preference, and many scientists believe that handedness is more of a continuous spectrum, rather than being defined by absolutes.
Over time, two new categories have joined the traditional lefties and righties. Initially, several theories postulated that a single gene was responsible for hand preference. The combination of both sets of this gene — inherited from our parents — would determine handedness. While these theories sound simple and convincing, there is no genetic evidence to date to back them up. Instead, research shows that several genes contribute around 25 percent toward handedness, and the rest is down to other factors.
But what could these other factors be? Are they environmental factors, such as upbringing or cultural influences, or is a more complex biological system responsible for the major factor in determining hand preference? One study suggested that individuals who were breast-fed for a minimum period of 6 weeks were less likely to be left-handed. These theories also try to explain the persistent and continuing presence of a left-handed minority about 15 percent of humans. The genetic proposal to explain hand preference states that there are two alleles, or two manifestations of a gene at the same genetic location, that are associated with handedness.
The D gene is more frequent in the population and is more likely to occur as part of the genetic heritage of an individual. It is the D gene that promotes right-hand preference in the majority of humans. The C gene is less likely to occur within the gene pool, but when it is present, the hand preference of the individual with the C gene is determined randomly. Individuals with the C gene will have a 50 percent chance of being right-handed and a 50 percent chance of being left-handed.
These theories of hand preference causation are intriguing because they can account for the fact that the side of hand preference of individuals with the C gene most left-handers and some right-handers can be influenced by external cultural and societal pressures, a phenomenon that researchers have documented.
These theories can also explain the presence of right-handed children in families with left-handed parents and the presence of left-handed children in families with right-handed parents. If the familial genetic pool contains C genes, then hand preference becomes amenable to chance influences, including the pressures of familial training and other environmental interventions that favor the use of one hand over the other.
The proposed genetic locus that determines hand preference contains an allele from each parent, and the various possible genetic combinations are DD individuals who are strongly right-handed, DC individuals who are also mostly right-handed, and CC individuals who are either right-handed or left-handed.
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