Human Laterality Information and Right or Left Hand Test

Ian C. Langtree - Writer/Editor for Disabled World (DW)
Published: 2020/02/04 - Updated: 2023/09/17
Publication Type: Charts / Graphs / Tables
Topic: Medical Calculators and Charts - Publications List

Page Content: Synopsis - Introduction - Main

Synopsis: Information, facts and statistics regarding human laterality, the preference for one side of the body over the other. Includes right or left handedness test. A cross-dominant person might write with the right hand and kick a ball using the left foot. Ambidexterity means a person has no preference for the use of the right or left hand.

Introduction

If you're left-handed you are in good company; Bill Gates, Oprah Winfrey, and Barack Obama are all left-handed. However, the majority of humans are right-handed. Many are also right-sided in general (they prefer to use their right eye, right foot and right ear if forced to make a choice between the two).

Main Item

International Left-Handers Day is held annually every August 13th. It was founded by the Left-Handers Club in 1992 - the club itself was founded in 1990. International Left-Handers Day is, according to the club, "an annual event when left-handers everywhere can celebrate their sinistrality (left-handedness) and increase public awareness of the advantages and disadvantages of being left-handed."

The term laterality refers to the preference most humans show for one side of their body over the other. Examples include left-handedness/right-handedness and left/right-footedness; it may also refer to the primary use of the left or right hemisphere in the brain. When a person is forced to use the hand opposite of the hand that they would naturally use, this is known as forced laterality, or more specifically forced dextrality. Ambidexterity is when a person has approximately equal skill with both hands and/or both sides of the body.

Continued below image.

Simple diagram of lateralization of human brain function.

Continued...

So We Have:

Right-handedness - The most common.
Left-handedness - Far less common than right-handedness.
Ambidexterity - Means a person has no marked preference for the use of the right or left hand. Equal ability to use both hands, is exceptionally rare.
Cross-dominance or mixed-handedness, hand confusion, or mixed dominance - A motor skill manifestation in which a person favors one hand for some tasks and the other hand for others, or a hand and the contralateral leg. For example, a cross-dominant person might write with the right hand and do everything else with the left one, or manage and kick a ball preferentially with the left leg. It can also refer to mixed laterality, which refers to a person favoring eyes, ears, feet, or hands on one side of the body.
Footedness - The natural preference of using the left or right foot for various purposes. It is the foot equivalent of handedness.
Ocular dominance, eye preference or eyedness - The tendency to prefer visual input from one eye to the other. It is somewhat analogous to the laterality of right or left-handedness - however, the side of the dominant eye and the dominant hand do not always match.
Earedness or Ear Advantage - The condition or tendency to hear with one ear more than the other. Your right ear is better than your left ear at receiving sounds from speech, whereas your left ear is more sensitive to sounds of music and song, according to American researchers behind a study of the hearing in 3,000 newborns. If you are a left-brain thinker, the chances are you use your right hand to hold your phone up to your right ear, according to a study from the Henry Ford Hospital in Detroit. 70% of people hold their phone to ear on the same side as dominant hand. 95% are left-brain thinkers but there is no greater incidence of brain tumors in right side of brain.

Approximate Statistics For the Above Are:

Favoring right hand: 88.2%
Ambidexterity: Very uncommon, about a 1% prevalence
Cross-dominance: Very uncommon, about a 1% prevalence.
Favoring right foot: 81.0%
Favoring right eye: 71.1%
Favoring right ear: 59.1%
Same hand and foot: 84%
Same ear and eye: 61.8%

Handedness Test

Though most people are right-handed or left-handed, there are different "degrees" of handedness. Some people use one hand for jobs that require skill and the other hand for jobs that involve reaching.

There are number of different tests and measurement scales used to assess the dominance of a person's right or left hand in everyday activities, also referred to as laterality. We have included one such handedness test for you to try below:

Hand Dominance Test
Hand Preference:	Always LEFT	Usually LEFT	No PREF	Usually RIGHT	Always RIGHT
For each of the questions below select a point option: Always RIGHT = +2 Usually RIGHT = +1 No preference = 0 Usually LEFT = -1 Always LEFT = -2
Writing a letter legibly	-2	-1	0	+1	+2
Throwing ball to hit a target	-2	-1	0	+1	+2
Playing game requiring use of a racquet	-2	-1	0	+1	+2
At top of broom when sweeping	-2	-1	0	+1	+2
At top of a shovel when shoveling	-2	-1	0	+1	+2
To hold a match when striking it	-2	-1	0	+1	+2
To hold scissors to cut paper	-2	-1	0	+1	+2
To hold thread to guide through the eye of a needle	-2	-1	0	+1	+2
To deal playing cards	-2	-1	0	+1	+2
To hammer a nail into wood	-2	-1	0	+1	+2
To hold toothbrush while cleaning teeth	-2	-1	0	+1	+2
To unscrew the lid of a jar	-2	-1	0	+1	+2
Determining Your Score
For each of the 12 questions, assign point values: Add up your scores for the 12 questions. The maximum score is +24 (extreme right handedness), the minimum score is -24 (extreme left handedness). YOUR TOTAL SCORE =_________
Interpreting Your Score
Scores can be divided into three parts: -24 to -9 = Left handed -8 to +8 = Mixed handed +9 to +24 = Right handed
Data from the paper of Briggs and Nebes (1975) for college students
	Left handed	Mixed handed	Right handed	TOTAL
Males	74 (8.9%)	47 (5.7%)	710 (85.4%)	831
Females	72 (9.4%)	37 (4.8%)	659 (85.8%)	768
Totals	146	84	1369	1599
Testing Other Aspects of Laterality Other aspects of laterality can also be tested quite simply. For example; Footedness is easily established by noting which foot is instinctively used to kick a ball. Ear preference is quite effectively tested by noting which ear tends to be used to listen on a telephone. Eye preference can be tested by noting which eye is used to look through a keyhole or a camera viewfinder. But another good test of "eyedness" can be carried out as follows: point with one finger at a distant object with both eyes open; then close one eye; if the finger is still well aligned with the object then the open eye is the dominant one (closing the other eye should then reveal that the finger is no longer closely aligned with the object). This questionnaire was adapted from the handedness questionnaire by Briggs, G.G. and Nebes, R.D., Patterns of hand preference in a student population, Cortex, 11:230-238, 1975)

Related Information

Author Credentials: Ian was born and grew up in Australia. Since then, he has traveled and lived in numerous locations and currently resides in Montreal, Canada. Ian is the founder, a writer, and editor in chief for Disabled World. Ian believes in the Social Model of Disability, a belief developed by disabled people in the 1970s. The social model changes the focus away from people's impairments and towards removing barriers that disabled people face daily. To learn more about Ian's background, expertise, and achievements, check out his bio.