Edinburgh Handedness Inventory

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The Edinburgh Handedness Inventory is a measurement scale used to assess the dominance of a person's right or left hand in everyday activities, sometimes referred to as laterality. The inventory can be used by an observer assessing the person, or by a person self-reporting hand use. The latter method tends to be less reliable due to a person over-attributing tasks to the dominant hand.

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The Edinburgh Handedness Inventory was published in 1971 by Richard Charles Oldfield [1] and has been used in various scientific studies [2] [3] as well as popular literature. [4]

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In human biology, handedness is the better, faster, or more precise performance or individual preference for use of a hand, known as the dominant hand. The incapable, less capable or less preferred hand is called the non-dominant hand. Right-handedness is most common; about 90% of people are right-handed. Handedness is often defined by one's writing hand, as it is fairly common for people to prefer to do some tasks with each hand. There are examples of true ambidexterity, but it is rare—most people prefer one hand for most purposes.

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Paul Satz was an American psychologist, and one of the founders of the discipline neuropsychology. His research on the relationship between the brain and human behavior spanned diverse topics including laterality, handedness, and developmental disorders. He published over 300 publications, received numerous grants and awards, and established the first neuropsychology lab. Towards the latter part of his career, Satz's research interests focused more on the cognitive deficits associated with head injury, dementia, and ageing.

An estimated 90% of the world's human population consider themselves to be right-handed. The human brain's control of motor function is a mirror image in terms of connectivity; the left hemisphere controls the right hand and vice versa. This theoretically means that the hemisphere contralateral to the dominant hand tends to be more dominant than the ipsilateral hemisphere, however this is not always the case and there are numerous other factors which contribute in complex ways to physical hand preference.

References

  1. Oldfield, RC (March 1971). "The assessment and analysis of handedness: The Edinburgh inventory". Neuropsychologia. 9 (1): 97–113. doi:10.1016/0028-3932(71)90067-4. PMID   5146491.
  2. Verdino, M; Dingman, S (April 1998). "Two measures of laterality in handedness: the Edinburgh Handedness Inventory and the Purdue Pegboard test of manual dexterity". Perceptual and Motor Skills. 86 (2): 476–8. doi:10.2466/pms.1998.86.2.476. PMID   9638746.
  3. Knecht, S; Dräger, B; Deppe, M; Bobe, L; Lohmann, H; Flöel, A; Ringelstein, E-B; Henningsen, H (December 2000). "Handedness and hemispheric language dominance in healthy humans". Brain. 123 (12): 2512–8. doi: 10.1093/brain/123.12.2512 . PMID   11099452.
  4. Wolman, David (2006). A left-handed Turn Around the World. ISBN   978-0-306-81498-3.