Cognitive Daily

ResearchBlogging.orgSeveral studies have confirmed this bizarre proposition: If you’re taking a test of rote memorization, like words from a list, move your eyes from side to side for about 30 seconds before you start. Really.

Researchers have found, with relative consistency, that if you saccade from left to right and back several times before a test of simple recall, you’re likely to do better. Why? It may be that this quick activity helps facilitate interaction between the brain hemispheres. Since split-brain patients have more difficulty recalling words than people with normal brains, any activity that encourages communication between the hemispheres is likely to increase recall.

If improving communication between the brain’s hemispheres is at the root of this seemingly bizarre effect, then a team led by Keith Lyle reasoned that people who have poorer interactions between the hemispheres should benefit more than others. Who has less interactions between hemispheres? People who are strongly right-handed. Handedness is actually not binary: Many people eat with the left hand, for example, but do everything else right-handed. A simple test can give you a sense of how dominant one hand or the other is. You can try an online version of the test here. Go ahead, give it a shot.

The results are expressed from -100 (completely left-domininant) to +100 (completely right-dominant). How do our readers do? Let’s make this a poll:



Lyle’s team used the same scale to test 142 college students for handedness. Those who scored higher than +80 on the test were categorized as strongly right-handed. Everyone else was put in a non-strongly-right-handed group.

Then the researchers asked them to memorize a list of 50 words that were flashed up on the screen for 2 seconds at a time. Then half the students watched for 30 seconds as a dot flashed alternately on the left and right side of the screen (they were instructed to keep their head still and follow the dot with their eyes). The other half watched a dot change color in the middle of the screen. Then they were asked to write down as many of the words as they could remember. Here are the results:

i-b6042d54c300ee71bf4c076bda05bafb-lyle1.png

Strongly right-handed students remembered significantly more words if they moved their eyes compared to keeping their eyes still. Non-strongly-right-handed students (including left-handers) remembered the same number of words regardless of whether they moved their eyes before the test.

But there’s another aspect to memory: how many words did respondents incorrectly think they had seen? Here are those results:

i-4e3d7da9056ca519c0b49959fbfc55ec-lyle2.png

Once again, strongly right-handed students had significantly fewer false alarms after they moved their eyes back and forth. But for non-strongly-right-handed people, the reverse occurred; moving their eyes caused them to falsely remember more words. So overall, while the eye-saccade exercise helped right-handers, for lefties and for those who didn’t have a strongly dominant hand, the exercise actually harmed their performance.

A second study confirmed these results and added another bizarre twist. You might think that only side-to-side movement would improve performance, but Lyle’s team found that moving your eyes up and down caused the same effect. This might seem to strike a blow for the hemispheric connectivity argument: the right and left visual fields are represented in different hemispheres of the brain, but up and down are not. But the researchers say that other studies have shown that any eye movements increase bilateral activity in the frontal eye field, so it’s still possible that hemispheric connectivity can explain the improved performance after eye movements.

So why doesn’t the exercise work the same way for left-handers? Left handers (and ambidextrous individuals) already have a high level of hemispheric connectivity. Lyle’s team speculates that there might be such a thing as too much connectivity, which results in a decrease in performance.

But if you scored higher than +80 on the handedness questionnaire, the results seem quite compelling: on tests of simple recall, doing this simple eye exercise beforehand might improve your score.

LYLE, K., LOGAN, J., & ROEDIGER, H. (2008). Eye movements enhance memory for individuals who are strongly right-handed and harm it for individuals who are not Psychonomic Bulletin & Review, 15 (3), 515-520 DOI: 10.3758/PBR.15.3.515

Comments

  1. #1 Dave
    April 16, 2009

    Couldn’t get that test to work – tried it on Firefox, IE7 and two different computers. I’m guessing I’m +90 right dominant

  2. #2 Dave Munger
    April 16, 2009

    Here’s a lower-tech version. Requires some calculation, but should work for pretty much everyone:

    http://www.cse.yorku.ca/course_archive/2006-07/W/4441/EdinburghInventory.html

  3. #3 Kat
    April 16, 2009

    I had problems with it too. looks like the second to last checkbox causes it to error out, error console in firefox mentions an invalid property. I skipped that box and scored a 90 so I just lumped myself in the 80 to 100 category.

  4. #4 Donna B.
    April 16, 2009

    It worked fine for me in Chrome, and put me at 60. I did have to find the broom and see which hand I put on top (left). Oddly enough, it’s reversed when using a rake.

  5. #5 Dave
    April 16, 2009

    I’m a +75 so should I do it or not?!

    Would there be any difference if pictures were used instead of words? or sounds / music.

  6. #6 Eric Lund
    April 16, 2009

    Did they have a large enough sample of strongly left-handed people to be able to separate out that category?

    It probably wouldn’t help me that much. I am cross-dominant: left hand (-70 on that test), right eye (which is why I always mouse right-handed). So I’m switching hemispheres regularly anyway.

  7. #7 Dave Munger
    April 16, 2009

    I don’t think they had a big enough sample to separate lefties. But my understanding of handedness is left-handers don’t differ much from ambidextrous. There’s a lot of bilateral action going on in everyone except strong RH-dominant.

  8. #8 hanna jörgel
    April 16, 2009

    I switched over to Safari and the test worked after Firefox proved incapable.

    -60 left. I’ve always thrown and used scissors with the right hand as far as I can remember. Some time with my left hand in a cast and a chronic injury made me rely more on my right hand.

    I’ve always wondered if early teaching myself how to play keyboards on my mom’s old Hammond organ helped me slide over into ambidexterity.

  9. #9 Joel
    April 16, 2009

    You should all move to Chrome… The “top nine pages” feature on startup is enough to make it worthwhile.

    Anyway, I scored a -65 (left handed) and was playing around moving my eyes back and forth and found it profoundly disorienting and dizzying, even after just a short time (3-5 seconds). I have two monitors and just quickly switched from left to right and back. I’m curious if right-handers have the same experience? Is there any research explaining this?

  10. #10 Inventor
    April 16, 2009

    I have a yoga book that shows a number of eye exercises
    including the exercise detailed above. They have been doing those excersizes for thousands of years.

  11. #11 Inventor
    April 16, 2009

    Dont ,move to chrome move to Joel’s house, or his mental asylum, wherever he lives.

  12. #12 a2lbd
    April 17, 2009

    Should we conclude from this test as far as studying is concerned, that teachers in classrooms should refrain to calling to attention students whose gazes are wandering afar from the blackboard ?

    Or is it preposterous ?

    PS: Firefox did the job for me on testing.

  13. #13 Sérgio
    April 17, 2009

    Joel, if you ever need that feature in Firefox, install the Fast Dial extension.

  14. #14 Lova Falk
    April 17, 2009

    I’m a 95% RH. When I was 11 yo, I trained myself to write with my left hand, just for a short period of time. Since then I experience more confusion with regard to direction of numbers consisting of two figures (e.g., saying 95 when the number is 59). Of course, this is an extremely questionable result of an experiment – but it fits with the tentative conclusion that too much connection isn’t good either…

  15. #15 Andrei
    April 17, 2009

    +100 right-handed on the self-diagnostic test, I gave this a go with rehearsal of some German vocab that I had recently attempted to commit to memory. My profoundly scientific test failed to find any support for the hypothesis.

  16. #16 Hypatia
    April 17, 2009

    Hanna writes: “-60 left. I’ve always thrown and used scissors with the right hand as far as I can remember.”

    Oh, please don’t throw scissors!

  17. #17 Ray Ingles
    April 17, 2009

    Seems like we lefties comment more. :-> -80 for me, though “augmented” is only -60; I got used to mousing right-handed ’cause there are just too few left-handed setups. I even play FPS games that way.

    I wonder if there are exercises that depress hemispheric interconnectivity?

  18. #18 gwern
    April 17, 2009

    There seems to be a copy here: http://louisville.edu/psychology/lyle/LyleLogan-RoedigerPB-R2008.pdf

    An interesting note, the dot/one’s eyes moved slower than one would expect: “The dot alternated between the left and right sides of the screen (approximately 27o of visual angle) once every 500msec for 30 sec. For the no-movement condition, a colored dot appeared in the center of the screen and cycled through six colors once every 500msec for 30 sec.”

  19. #19 Eric
    April 18, 2009

    Well I have a potentially relevant observation.

    When I study for exams, and only then, both of my legs start to bounce up and down rythmically. It is like they are on auto-pilot. I can stop them if I wanted, but otherwise they bounce away of their own volition.

    Since I have a gpa that is very high I’m wondering if this might gave the same effect? It especially happens when I have gone over the material a number of times already.

    …. Or maybe it’s just nerves

  20. #20 Random Thinker
    April 18, 2009

    A thought: This might also work because it mimics the action of reading, thus priming one for recall of previously read knowledge.

  21. #21 Andy
    April 18, 2009

    Cool, I came out as 0.0, the perfect balance :). I did a Myers-Briggs test and was right in the middle too :)

    I prefer different hands when writing on different surfaces. The angle is mainly what changes it for me – on a table, I use left hand. On a whiteboard or clipboard I use right. But if I’m writing on a touchscreen-like thing and it is flat, I still like right hand.

  22. #22 seo wales
    April 18, 2009

    @Random Thinker – it would be interesting to see how the language background of experimental subjects affected results, Hebrew is R-to-L and Mandarin (IIRC) is Bottom-to-Top, is the effect the same for people used to reading those languages?

  23. I hope it works ’cause I’m strongly right-handed I’m gonna use it :)
    For all I can righ- and left-handed, with and without dyslexia I can recommend ‘Dennison’s Method’ – they are proven to improve ability to associate facts, remember and learn. Moreover make the coordination better and are great fun.

  24. #24 nancwil
    April 22, 2009

    Andy,

    I like you am ambidextrous and write with both hands depending on the angle but also on the convenience factor. I did this naturally as a child in school when called upon to write on the chalkboard. I would start out with my left hand but when it reached to a point about right in front of me I just switched hands and continued writing not thinking anything of it until I heard rumblings of those watching. The thing I noticed most about it is that it has interferred with my level of coordination. For instance if you were to throw a ball at me and ask me to “Catch” suddenly, rather than just reaching for it with my dominant hand, I experience a hesitation in trying to decide which hand to use, which usually results in my responding too late to actually catch it. That is just one example but it occurs in other situations too. I was not very good at the more active contact sports…..but can overcome this with practice……

  25. #25 deedee
    May 23, 2009

    People also use eye-access clues to recall information. Looking up to the right or left with ones’ eyes to the corner of the eyes (just moving the eyes) seems an ingrained, innate means of accessing memory. Nearly everyone ones does this; just look at how people move their eyes the next time they are trying to recall somethings.

  26. #26 wowser
    May 23, 2009

    @deedee: Here are those eye-accessing clues (based on NLP research):

    Looking up and to the left: Visual recall

    Remembering what something looked like.

    Looking straight over to the left: Auditory recall

    Remembering what something sounded like.

    Looking down and to the left: Accessing internal dialogue.

    Often referred to as “that voice inside your head”. When you say things to yourself like “great job”, or “I told you so”, etc.

    Looking up and to the right: Visually creative

    Someone asking themselves “What would that look like if I saw it?”

    Looking straight over to the right side: Auditory construct

    An imagined sound. “I wonder what that might sound like?”

    Looking down and to the right: Accessing feelings

    Peoples eyes generally go here when pondering emotions, physical sensations, pain, pleasure.

  27. #27 deedee
    May 23, 2009

    @Andy, @nancwil:

    I didn’t come out as completely ambidextrous, a +20. I do somethings with my right hand more than my left and vice versa. I drink and use keys with my left hand almost exclusively; I use computer mouse right-handed. I write right-handed mostly, but left-handed if need to. Same for drawing.

  28. #28 workout
    June 9, 2009

    I like you am ambidextrous and write with both hands depending on the angle but also on the convenience factor. I did this naturally as a child in school when called upon to write on the chalkboard.

  29. #29 Getalong
    December 28, 2009

    Hello! I had to figure out about the broom too, and suspected the question has it backwards. Does it mean a push broom or the regular kind? When I use the regular kind it depends mostly on where the dirt is located and which way I am trying to push it! But if I am walking down a sidewalk brushing from side to side to push all the leaves off it, then my left hand is on top. For everything else I am right handed.