Have a look at this pic of a mature pencil grip and you can see how these tripod fingers thumb, index and middle fingers are working well together to control the pencil.
Types[ edit ] Right-handedness is most common. Right-handed people are more skillful with their right hands when performing tasks. Left-handed people are more skillful with their left hands when performing tasks.
Those who learn it still tend to favor their originally dominant hand.
Occurrences during prenatal development may be important; researchers studied fetuses in utero and determined that handedness in the womb was a very accurate predictor of handedness after birth. Since speaking and handiwork require fine motor skills, its presumption is that it would be more efficient to have one brain hemisphere do both, rather than having it divided up.
Since in most people, the left side of the brain controls speaking, right-handedness predominates. This theory also predicts that left-handed people have a reversed brain division of labor. Left-handed individuals have a heterogeneous brain organization in which their brain hemispheres are either organized in the same way as right-handers but with the hemispheres reversed or even such that both hemispheres are used for verbal processing.
When the average is taken across all types of left-handedness, it shows that left-handers are less lateralized. However, the growing weight of evidence from linkage and genome-wide association studies suggests that genetic variance in handedness cannot be explained by a single genetic locus.
Nodal signaling and ciliogenesis also play a role in the development of brain asymmetry handedness is an outward reflection of brain asymmetry for motor function. Diethylstilbestrol animal studies "suggest that estrogen affects the developing brain, including the part that governs sexual behavior and right and left dominance".
About two-thirds of fetuses present with their left occiput back of the head at birth. This partly explains why prematurity results in a decrease in right-handedness.
Previc argues that asymmetric prenatal positioning creates asymmetric stimulation of the vestibular system, which is involved in the development of handedness.
In fact, every major disorder in which patients show reduced right-handedness is associated with either vestibular abnormalities or delay,  and asymmetry of the vestibular cortex is strongly correlated with the direction of handedness. Research on this topic suggests there may exist a weak association between ultrasound screening sonography used to check on the healthy development of the fetus and mother during pregnancy and left-handedness.
This is especially shown when observing hand dominance in one versus two-handed grasping tasks. Between 36 and 48 months, variability between handedness in one handed grasping begins to decline significantly.
This difference can be seen earlier in bi-manual manipulation tasks. The increase in required single hand grasping activities such as writing or coloring can force children to develop a hand preference.
Handedness and mathematical ability and List of musicians who play left-handed In his book Right-Hand, Left-Hand, Chris McManus of University College London argues that the proportion of left-handers is increasing and left-handed people as a group have historically produced an above-average quota of high achievers.
Also, a slightly larger number of left-handers than right-handers are especially gifted in music and math. A study of musicians in professional orchestras found a significantly greater proportion of talented left-handers, even among those who played instruments that seem designed for right-handers, such as violins.
Similarly, studies of adolescents who took tests to assess mathematical giftedness found many more left-handers in the population. Goodman also found that left-handers were overrepresented at the low end of the cognitive spectrum, with the mentally disabled being twice as likely to be left-handed compared to the general population, as well as generally lower cognitive and non-cognitive abilities amongst left-handed children.
In the article they assessed 38 infants and followed them through to 12 months and then again once they became toddlers from 18—24 months. What they discovered was that when a child developed a consistent use of its right or left hand during infancy such as using the right hand to put the pacifier back in, or grasping random objects with the left handit was more likely to have superior language skills as a toddler.
Children who became lateral later than infancy i. Health[ edit ] Lower-birth-weight and complications at birth are positively correlated with left-handness. However, left-handers enjoy an advantage in fighting and sports increasing their likelihood of reproduction.
Goodman attributes this disparity to higher rates of emotional and behavioral problems in left-handed people. Please help improve this article by adding citations to reliable sources. Unsourced material may be challenged and removed.
January See also: Southpaw stance Interactive sports such as table tennis, badminton and cricket have an overrepresentation of left-handedness, while non-interactive sports such as swimming show no overrepresentation. Smaller physical distance between participants increases the overrepresentation.
In fencingabout half the participants are left-handed. Historical batting averages show that left-handed batters have a slight advantage over right-handed batters when facing right-handed pitchers.I provide advice about how to write novels, comic books and graphic leslutinsduphoenix.com of my content applies to fiction-writing in general, but I also provide articles specifically about superhero stories..
Generic Physical Superpowers. Superstrength. Earlier this year, Prof Zicari had the pleasure of interviewing Philippe Kahn, a mathematician, well-known technology innovator, entrepreneur and founder of four technology companies: Fullpower Technologies, LightSurf Technologies, Starfish Software and Borland.
I suppose I've had an interest in becoming ambidextrous for quite some time. I few important events that come to mind both happened my freshman year in high school. Ambidextrous people have the ability to use both hands with equal dexterity.
But the ambidextrous probably prefer to write with their right hands, since lefties always smudge what they've written as they drag their hand across the page. This is the most common kind of handedness, covering up to 90% of the world’s population, depending on the definitions used, with perhaps 60% being strongly right .
Very interesting. I am truly ambidextrous and have been since I was 6. I used to change hands when writing, which drove my teachers crazy. Now, I write and cut with my right hand, and use either hand for drawing, painting, and everything else.