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Most of us have one dominant hand. We find it nigh on impossible to do very delicate or dextrous activities with our other-hand. This seems like an apparent weakness, and a rather odd one when you first think about it.

Cursory internet searches revealed unexpected findings. One website said it has mostly negative effects on the brain. However I don't trust the source at all.

I'd be interested to know about the "story" about the good and bad of ambidextrous physiology. Particularly, I am interested in the neuroscience of ambidextrous people.

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It would also be interesting to know whether our ancestors used both the hands and using just one hand is recently evolved – biogirl Apr 29 '14 at 15:58
@biogirl great comment needs more attention from everyone – agha rehan abbas Jul 1 '14 at 16:45
@agha rehan abbas Thanks ! Thinking about something from evolution point of view always helps. – biogirl Jul 1 '14 at 17:50
@biogirl It's a contentious issue, but chimps do indeed display handed-ness for tasks like termite fishing. – Good Gravy Nov 24 at 12:27

2 Answers 2

I think that the advantages of using both hands with equal ease is quite evident whether it be sports, at your work or while you are doing your household chores.

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An obvious advantage is using both hands to write or draw with both at the same time.

I would be focusing on the disadvantages that may be faced.

1) Ambidextrous people are more prone to suffer from Synaesthesia (reference)

2) They are likely to possess (not necessarily) the LRRTM1 gene which is linked with Schizophrenia (reference).

3) They score lesser in intelligence testing (reference).

4) Mixed handed children are more likely to suffer from ADHD (reference).

5) Mixed handedness is associated with greater age-related decline (reference)

6) They are easier to anger and influence emotionally (reference).

There are quite a few studies that have pointed out that it may not be all that good a condition but Leonardo da Vinci who was probably the most diversely talented man who ever lived is said to have been ambidextrous. He apparently could draw with one hand and write with the other at the same time, so I would have to say that the positives of the condition are extremely good (reference).


This probably qualifies as a second question :-D but I just saw a thought by biogirl in the comments section on "whether our ancestors used both the hands and using just one hand is recently evolved" and she has a point there. From a study publlished in 1977 I quote.

The predominance of the right hand over the left was also reported among Egyptian art forms 3,500 to 4,500 years old, where the ratio of left- to right-handers was 9:111 and 5:100, respectively. However, going further back using the "Draw-a-Man Test," found that ancient paleolithic man, from 1,750,000 to 8,000 years B.C., was probably either more ambidextrous or that there was a greater proportion of left-handers than there are now. (reference)

Also from a study titled "Evolutionary Back Grounds of Human Left Handedness", the authors concluded that

For most manual tasks, especially those tasks involved in competitive activities, increasing performance by the specialization of one hand is certainly adaptive. Aggressive interactions are responsible for fundamental selection pressures acting during primate and human evolution. The higher prevalence of right-handedness might well be due to a previously existing cerebral bias. But the specialization of one forelimb leading to right or left-handedness is better viewed as the result of natural selection. (reference)

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I cannot expand on what @TheLastWord's answer, which is very thorough. One thing I think is significant is that ambidextrous people have a lot of communication between each side of the brain.


Right and left brained people are popularly thought to be different in terms of creativity, however this is actually a myth. Ambidexterity is as one would imagine a spectrum, and even people who appear to be equally capable with either hand have a preference, and this is more common in left-handed people (although the word actually is derived from the meaning for two right hands!).

What is true that ambidextrous people, or people who use both hands for different tasks, are more creative thinkers than one-handed people, because being ambidextrous involves having both sides of the brain talk to each other a lot, which seems to be involved in creating flexible thinking. The myth of the creative left-hander arises from the fact that being ambidextrous is more common amongst left-handers than right-handers, so a grain of truth in the idea of the creative left-hander, but not much. -Ben Ambridge

Another advantage that came out of my search was certainly unexpected was the following:

Ambidexterity is also useful after surgery on a dominant hand or arm, as it allows the patient to use their non-dominant hand with equal facility as the limb which is recovering from surgery. -Wikipedia

By far and away the biggest advantage is obviously sports, where ambidextrous people can dominate due to their versatility and unpredictability.


If one is lucky enough to have ambidexterity without any of the synesthesia (which is rather rare) I can't imagine any day-to-day disadvantages for ambidextrous folks.

For further reading, I would read about ambisinistral folks, another interesting although rather debilitating form of handedness.

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