Biology Stack Exchange is a question and answer site for biology researchers, academics, and students. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

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.

share|improve this question
4  
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. – James Nov 24 '15 at 12:27
    
One side effect of being ambidextrous is that I also find it very easy to read mirror writing. This may seem like an advantage but in practice it can cause difficulties. I frequently find myself pushing glass doors when I should be pulling because I have inadvertently read the instructions through the glass on the opposite side of the door and my brain has not registered that it is the wrong way round. – user20562 Dec 10 '15 at 8:40

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.

enter image description here

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).

edit:

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)

share|improve this answer

protected by Chris Dec 10 '15 at 8:51

Thank you for your interest in this question. Because it has attracted low-quality or spam answers that had to be removed, posting an answer now requires 10 reputation on this site (the association bonus does not count).

Would you like to answer one of these unanswered questions instead?

Not the answer you're looking for? Browse other questions tagged or ask your own question.