Reflexes

“The the­atre is the invol­un­tary reflex of the ideas of the crowd.” ~ Sarah Bernhardt

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Have you ever won­dered why you often pull your fin­ger away from a sharp pointed object? It is due to reflex. Reflexes refer to invol­un­tary and often inborn actions that take place in response to stim­uli, which are detectable changes in either the inter­nal or the exter­nal envi­ron­ment. Reflexes are impor­tant for pro­tect­ing the body against harm such as, in the exam­ple above, a reflex to avoid hurt­ing the fin­ger by remov­ing it even before a “This will prick you!” mes­sage reaches your brain.

As peo­ple grow up into matu­rity, dif­fer­ent types of reflexes are exhib­ited. Malina et al. say that prim­i­tive reflexes, also called infan­tile, infant or new­born reflexes, are those reflexes that begin in the cen­tral ner­vous sys­tem that are dis­played by nor­mal infants, but not by neu­ro­log­i­cally intact grown-ups, in response to par­tic­u­lar stim­uli. As a child moves through nor­mal child devel­op­ment, their pres­ence or absence at the right stage of devel­op­ment is an indi­ca­tion of the child’s state of health. Sally Blythe argues that pos­tural reflexes refer to those reflex actions that assist to main­tain the body in upright and bal­anced posi­tion. They also play an impor­tant role in pro­vid­ing adjust­ments essen­tial for sus­tain­ing a steady pos­ture dur­ing vol­un­tary activ­i­ties. Jan Piek says that prim­i­tive reflexes are sequen­tially replaced by pos­tural reflexes, which enables the child to gain com­plete con­trol of the body move­ments. Loco­mo­tion reflexes refer to those reflexes that aid var­i­ous vol­un­tary move­ments such as creep­ing, stand­ing, step­ping and even swim­ming if the child is placed in water.

Ref­er­ences:
Blythe, S. (2009). Atten­tion, Bal­ance and Coor­di­na­tion: The A.B.C. of Learn­ing Suc­cess. Malden, MA: John Wiley & Sons Ltd.
Malina, R., Bouchard, C. & Bar-Or, O. (2004). Growth, Mat­u­ra­tion, and Phys­i­cal Activ­ity. Cham­paign, IL: Human Kinet­ics.
Piek, J. (2006). Infant Motor Devel­op­ment. Cham­paign, IL: Human Kinetics.