Grasp

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For other uses, see Grasp (disambiguation).

A grasp is an act of taking, holding or seizing firmly with (or as if with) the hand. An example of a grasp is the handshake, wherein two people grasp one of each other's like hands.

In zoology particularly, prehensility is the quality of an appendage or organ that has adapted for grasping or holding.

Development[edit]

The development of grasping is an important component of child development stages, wherein the main types of grasps are:

  • Raking grasp, wherein the fingers, but not including the thumb, do all the holding.[1]
  • Palmar grasp, wherein the fingers squeeze against the palm, instead of against themselves as in the raking grasp.[1] Children are usually able to use a palmar grasp by the age of 6 months.[2][3]
  • Pincer grasp wherein the pointer finger and the thumb squeeze to grasp an object.[1] Children are usually able to use a pincer grasp by the age of 9 to 10 months.[2][3]

Reflex[edit]

Grasp reflex of a 5 month old baby boy

The palmar grasp reflex (sometimes simply called grasp reflex) is among the primitive reflexes and appears at birth and persists until five or six months of age.[4] When an object is placed in the infant's hand and strokes their palm, the fingers will close and they will grasp it. The grip is strong but unpredictable; though it may be able to support the child's weight, they may also release their grip suddenly and without warning. The reverse motion can be induced by stroking the back or side of the hand.

References[edit]

  1. ^ a b c Page 176, section "Grasp" in: Kay Alicyn Ferrell (2011). Reach Out and Teach: Helping Your Child Who Is Visually Impaired Learn and Grow. Lightning Source UK Ltd. ISBN 0-89128-457-5. 
  2. ^ a b Seminars in child and adolescent psychiatry (second edition) Ed. Simon G. Gowers. Royal College of Psychiatrists (2005) ISBN 1-904671-13-6
  3. ^ a b Laura E. Berk (2012). Infants and children: Prenatal through middle childhood. Allyn & Bacon. 
  4. ^ "C Section Photo Shows Baby Grabbing Doctor's Hand From Inside The Womb". Blisstree.com.