<p>I would first like to discuss the concept of lateralization and clear up a common misconception about hemispheric dominance.</p>
<blockquote>
<p>&quot;A brain is considered to be asymmetrical (or lateralized) if one side (hemisphere or other brain region) is <strong>structurally different</strong> from the other <strong>and/or performs a different set of functions</strong>.&quot; (<a href="https://www.sciencedirect.com/science/article/abs/pii/S014976349700050X" rel="nofollow noreferrer">Bisazza et al., 1998</a>).</p>
</blockquote>
<p>A good example is the lateralization of language which relates to handedness. It has been widely accepted that a majority of people are left dominant for language, although right dominance increases with the degree of left handedness (<a href="https://academic.oup.com/brain/article/123/12/2512/325690" rel="nofollow noreferrer">Knecht et al., 2000</a>).</p>
<p>Lateralization and behavioural asymmetries are neither restricted to language or humans (<a href="https://www.sciencedirect.com/science/article/abs/pii/S014976349700050X" rel="nofollow noreferrer">Bisazza et al., 1998</a>). In the scientific community, hemispheric dominance is usually discussed in the context of a specific function. However, there is a <strong>common misconception</strong> by those who have an incomplete understanding of brain lateralization, particularly worsened by the spread of popular science articles and pseudoscientific tests (such as the one linked to in the comments) that <strong>wrongly assumes there is an overall dominance of one side of the brain</strong> (with left corresponding to logical and analytical thinking and right corresponding to emotional and creative thinking), that determines your personality trends. This is an incorrect oversimplification that is explained in a <a href="https://rationalwiki.org/wiki/Hemispheric_dominance" rel="nofollow noreferrer">good article</a> by RationalWiki.</p>
<p>Thus, your question is misguided in focusing on changes in hemispheric dominance. Even if you focused on change of lateralization for a specific function, this is unlikely as it requires substantial reorganization of the brain that is really only observed during development and to a much smaller extent following brain injury. However it is still good to question what changes there may be due to using a non-dominant hand more often! In fact (<a href="https://www.sciencedirect.com/science/article/abs/pii/S0278262607000565" rel="nofollow noreferrer">Teixeira and Teixeira, 2007</a>) looks at how <strong>practice with the non-preferred hand alters manual preference for a specific task</strong>, and suggests this generalizes to other related motor tasks (<a href="https://doi.org/10.1007/s00221-007-1148-0" rel="nofollow noreferrer">Teixeira and Okazaki, 2007</a>). <strong>The task used in their 2007 study involves sequentially touching the thumb with (in order) the ring, middle, little, and index fingers. The goal is to complete 5 cycles without interruption in the shortest time possible.</strong> They assess this before, after, and 30 days following practice, observing a noticeable shift in those that are allowed to practice compared to controls. You can choose a similar task and/or something different (for example, score in a quick video game that requires pointing with the trackball) and measure how you improve in comparison to a friend who doesn't practice with the left hand.</p>
<p>Ironically, they discuss how the <strong>left premotor cortex is dominant for learning sequential tasks</strong> (whether performed with right or left hand) and so might limit the observable shifts. For this reason it might be good to try their task to compare with that study and also your own task for personal interest.  <strong>If you are really interested in how performance and practice (especially long term) can affect the brain, there is lots of existing literature and imaging studies on the differences in brains of musicians</strong> compared to non-musicians or amateurs. Due to years of practice, professional musicians often have differences in and sometimes larger motor areas (<a href="https://onlinelibrary.wiley.com/doi/10.1111/j.1749-6632.2001.tb05739.x/full" rel="nofollow noreferrer">Schlaug, 2006</a>), increased cerebellar volume (<a href="https://academic.oup.com/cercor/article/13/9/943/342632" rel="nofollow noreferrer">Hutchinson et al., 2003</a>), increased auditory cortical representation (<a href="https://www.nature.com/articles/33918" rel="nofollow noreferrer">Pantev et al., 1998</a>) and increased assymetries such as in the planum temporale (<a href="https://www.science.org/doi/abs/10.1126/science.7839149" rel="nofollow noreferrer">Schlaug et al., 1995</a>).</p>

CC BY-SA 3.0
2012-06-16T01:36:35.200Z
Thanks a lot for such a thorough answer! Looks like I've got some reading to do :)
ajk
CC BY-SA 4.0
2012-06-15T22:00:52.490Z
2022-05-31T13:53:20.383Z
2022-05-31T13:53:20.383Z
Vielle
<p>I've recently started using my trackball left-handed after being right-handed my whole life. The motivation is partly to balance out wrist strain, and partly to see how much my brain rejects the idea.</p>

<p>Since I am at the computer for a good portion of the day, this is a fundamental change. I started to wonder whether it might actually have some measurable impact on <a href="http://en.wikipedia.org/wiki/Lateralization_of_brain_function" rel="noreferrer">hemispheric dominance</a>, and found (unsurprisingly) that Google had some links which posed the same question. To this point I have only my own admitted ignorance combined with unsubstantiated claims on the Internet. </p>

<p><strong>Is there a reasonably reliable and convenient way to measure changes in hemispheric dominance over time?</strong></p>

<p><strong>Edit</strong>: As I mentioned, I did some Googling around about the potential connection between dominant mouse hand and hemispheric dominance. The only tools I discovered along the way were simple questionnaires. I took 3-4 of them in the absence of any better ideas, and will repeat them over the next few months. I suspect that using Brain Age-style games or Lumosity might be more useful than a questionnaire, but wonder if results would change more due to practice than anything else. I was hoping that I overlooked something that more directly targets hemispheric dominance.</p>

CC BY-SA 3.0
2012-06-14T19:34:49.553Z
I've never heard of handedness "changing" like this. Handedness is also distinct from hemispheric dominance; while strongly related, right handedness does not *necessitate* left hemisphere dominance
Zelda
CC BY-SA 3.0
2012-06-14T20:01:18.303Z
I don't expect to change my dominant hand altogether. I see nothing but pain and failure when it comes to switching my writing/golf/guitar hand, for example. I also didn't mean to imply that being right-handed necessarily implies strong left hemisphere dominance. I was just curious whether changing this one isolated behavior could have measurable side effects.
ajk
CC BY-SA 3.0
2012-06-15T02:57:58.113Z
Can you integrate some of the [initial research](http://meta.cogsci.stackexchange.com/q/66/29) you did into your question and what you have concluded so far? I am assuming you are not looking for questionairs [like this](http://frank.mtsu.edu/~studskl/hd/hemispheric_dominance.html) as your answer.
Artem Kaznatcheev
CC BY-SA 3.0
2012-06-15T04:02:23.543Z
Sure Artem, hopefully my edit clarifies things a bit. I realize that this is a fairly silly request all things considered. I don't put much stock in the usefulness of the questionnaires, but understand that there is only one test subject (me) and enough variables that it will be difficult to isolate changes in one facet of brain activity with any real reliability. As I think about it more, I'm realizing that this question may need to be closed.
ajk
CC BY-SA 3.0
2012-06-15T19:35:52.987Z
I have undeleted this question because I think it is a good, answerable question, and [I was asked in chat to bring it back](http://chat.stackexchange.com/transcript/message/4977246#4977246). If this bothers you ajk, please let me know.
Josh
CC BY-SA 3.0
2012-06-15T20:22:58.983Z
That's perfectly fine. I have a lot of interest in the topic but close to 0 expertise, so I was worried about unintentionally clogging the site with nonsense.
ajk
CC BY-SA 3.0
2012-06-15T21:14:41.810Z
@ajk I think your question (although shows a misconception by those less familiar with the topic) is very good and provides an excellent opportunity for you and others to learn more. I'm working on an answer right now and will post it shortly!
Vielle
CC BY-SA 3.0
2012-06-15T23:10:48.830Z
@ajk Don't worry, if you clog the site with nonsense we'll just delete it :D! Serious, but that's quite rare; almost always a post is closed first with a reason why the post needs improvement. Deletion is for old closed stuff that never improved or outright spam/gibberish. If it's worthy of a close, someone will tell you, as is we just wanted to improve your question.
Zelda
<neuroscience><measurement><experimental-psychology>
Measuring changes in hemispheric dominance over time
ajk
# Measuring changes in hemispheric dominance over time

(Asked by: username_0 on 2012-06-14)

I've recently started using my trackball left-handed after being right-handed my whole life. The motivation is partly to balance out wrist strain, and partly to see how much my brain rejects the idea.

Since I am at the computer for a good portion of the day, this is a fundamental change. I started to wonder whether it might actually have some measurable impact on [hemispheric dominance](http://en.wikipedia.org/wiki/Lateralization_of_brain_function), and found (unsurprisingly) that Google had some links which posed the same question. To this point I have only my own admitted ignorance combined with unsubstantiated claims on the Internet.

**Is there a reasonably reliable and convenient way to measure changes in hemispheric dominance over time?**

**Edit**: As I mentioned, I did some Googling around about the potential connection between dominant mouse hand and hemispheric dominance. The only tools I discovered along the way were simple questionnaires. I took 3-4 of them in the absence of any better ideas, and will repeat them over the next few months. I suspect that using Brain Age-style games or Lumosity might be more useful than a questionnaire, but wonder if results would change more due to practice than anything else. I was hoping that I overlooked something that more directly targets hemispheric dominance.

**Tags:** neuroscience, measurement, experimental-psychology

> **Comments:**
> **username_1**: I've never heard of handedness "changing" like this. Handedness is also distinct from hemispheric dominance; while strongly related, right handedness does not *necessitate* left hemisphere dominance  
> **username_0**: I don't expect to change my dominant hand altogether. I see nothing but pain and failure when it comes to switching my writing/golf/guitar hand, for example. I also didn't mean to imply that being right-handed necessarily implies strong left hemisphere dominance. I was just curious whether changing this one isolated behavior could have measurable side effects.  
> **username_2**: Can you integrate some of the [initial research](http://meta.cogsci.stackexchange.com/q/66/29) you did into your question and what you have concluded so far? I am assuming you are not looking for questionairs [like this](http://frank.mtsu.edu/~studskl/hd/hemispheric_dominance.html) as your answer.  
> **username_0**: Sure Artem, hopefully my edit clarifies things a bit. I realize that this is a fairly silly request all things considered. I don't put much stock in the usefulness of the questionnaires, but understand that there is only one test subject (me) and enough variables that it will be difficult to isolate changes in one facet of brain activity with any real reliability. As I think about it more, I'm realizing that this question may need to be closed.  
> **username_3**: I have undeleted this question because I think it is a good, answerable question, and [I was asked in chat to bring it back](http://chat.stackexchange.com/transcript/message/4977246#4977246). If this bothers you username_0, please let me know.  
> **username_0**: That's perfectly fine. I have a lot of interest in the topic but close to 0 expertise, so I was worried about unintentionally clogging the site with nonsense.  
> **username_4**: @username_0 I think your question (although shows a misconception by those less familiar with the topic) is very good and provides an excellent opportunity for you and others to learn more. I'm working on an answer right now and will post it shortly!  
> **username_1**: @username_0 Don't worry, if you clog the site with nonsense we'll just delete it :D! Serious, but that's quite rare; almost always a post is closed first with a reason why the post needs improvement. Deletion is for old closed stuff that never improved or outright spam/gibberish. If it's worthy of a close, someone will tell you, as is we just wanted to improve your question.  

---

## 1 answers

### Answer by username_4 on 2012-06-15. Score: 7 | Accepted answer

I would first like to discuss the concept of lateralization and clear up a common misconception about hemispheric dominance.

> "A brain is considered to be asymmetrical (or lateralized) if one side (hemisphere or other brain region) is **structurally different** from the other **and/or performs a different set of functions**." ([Bisazza et al., 1998](https://www.sciencedirect.com/science/article/abs/pii/S014976349700050X)).

A good example is the lateralization of language which relates to handedness. It has been widely accepted that a majority of people are left dominant for language, although right dominance increases with the degree of left handedness ([Knecht et al., 2000](https://academic.oup.com/brain/article/123/12/2512/325690)).

Lateralization and behavioural asymmetries are neither restricted to language or humans ([Bisazza et al., 1998](https://www.sciencedirect.com/science/article/abs/pii/S014976349700050X)). In the scientific community, hemispheric dominance is usually discussed in the context of a specific function. However, there is a **common misconception** by those who have an incomplete understanding of brain lateralization, particularly worsened by the spread of popular science articles and pseudoscientific tests (such as the one linked to in the comments) that **wrongly assumes there is an overall dominance of one side of the brain** (with left corresponding to logical and analytical thinking and right corresponding to emotional and creative thinking), that determines your personality trends. This is an incorrect oversimplification that is explained in a [good article](https://rationalwiki.org/wiki/Hemispheric_dominance) by RationalWiki.

Thus, your question is misguided in focusing on changes in hemispheric dominance. Even if you focused on change of lateralization for a specific function, this is unlikely as it requires substantial reorganization of the brain that is really only observed during development and to a much smaller extent following brain injury. However it is still good to question what changes there may be due to using a non-dominant hand more often! In fact ([Teixeira and Teixeira, 2007](https://www.sciencedirect.com/science/article/abs/pii/S0278262607000565)) looks at how **practice with the non-preferred hand alters manual preference for a specific task**, and suggests this generalizes to other related motor tasks ([Teixeira and Okazaki, 2007](https://doi.org/10.1007/s00221-007-1148-0)). **The task used in their 2007 study involves sequentially touching the thumb with (in order) the ring, middle, little, and index fingers. The goal is to complete 5 cycles without interruption in the shortest time possible.** They assess this before, after, and 30 days following practice, observing a noticeable shift in those that are allowed to practice compared to controls. You can choose a similar task and/or something different (for example, score in a quick video game that requires pointing with the trackball) and measure how you improve in comparison to a friend who doesn't practice with the left hand.

Ironically, they discuss how the **left premotor cortex is dominant for learning sequential tasks** (whether performed with right or left hand) and so might limit the observable shifts. For this reason it might be good to try their task to compare with that study and also your own task for personal interest. **If you are really interested in how performance and practice (especially long term) can affect the brain, there is lots of existing literature and imaging studies on the differences in brains of musicians** compared to non-musicians or amateurs. Due to years of practice, professional musicians often have differences in and sometimes larger motor areas ([Schlaug, 2006](https://onlinelibrary.wiley.com/doi/10.1111/j.1749-6632.2001.tb05739.x/full)), increased cerebellar volume ([Hutchinson et al., 2003](https://academic.oup.com/cercor/article/13/9/943/342632)), increased auditory cortical representation ([Pantev et al., 1998](https://www.nature.com/articles/33918)) and increased assymetries such as in the planum temporale ([Schlaug et al., 1995](https://www.science.org/doi/abs/10.1126/science.7839149)).

> **Comments:**
> **username_0**: Thanks a lot for such a thorough answer! Looks like I've got some reading to do :)  

---

