What Makes Rocking Motion So Soothing?

[jobyts]

Why is it that a rocking motion gives a soothing effect? I guess it has to do something with brain fluids, but no clear answer.

 

[nismaratwork]

http://www.eric.ed.gov/ERICWebPorta...&ERICExtSearch_SearchType_0=no&accno=ED046504

A brief narrative description of the journal article, document, or resource. In this study designed to compare the relative pacifying properties of horizontal and vertical rocking, 13 infants (mean age--58 days) were each tested on two subsequent days. The rocking device was a cradle that could be manipulated to produce side-to-side rocking similar to a commercial cradle or up-and-down rocking. In its up-and-down mode, the cradle was moved through a 4-inch vertical excursion. Each subject received one mode of rocking in one daily session and the other mode on the following day. The subject's activity was independently rated on a 6-point scale every 30 seconds by two observers, and by an Electro-Craft Movement Transducer placed under the mattress of the cradle. Each day the infant received two 5-minute periods of rocking preceded and followed by a 5-minute observation period. Scores showed that activity during rocking decreased; but with termination of rocking, activity returned to the baseline level following the first rocking period. Activity after the second rocking period did not rise to the initial level. The up-and-down mode was more effective as a soother than the side-to-side mode. Transducer scores were in agreement with observer scores. (Author/AJ)

http://www.jstor.org/pss/1127705

I've read everything from rocking being a mild form of repetitive exercise:
http://www.rochester.edu/pr/releases/med/watson.htm

To it being a kind of "pre-programmed" preference because as an infant it helps to build balance. http://www.lifespan.org/services/mentalhealth/articles/stress/rocking_chairs.htm

Really, I don't think it has to do with one reason, but movement of the brain or CSF would seem to be the LEAST likely culprit.

 

[zoobyshoe]

I would suspect it's not the rocking, per se, that has a soothing effect, but the rhythm. Oliver Sacks gives numerous examples of the power of rhythm in his book Musicophilia. The most remarkable one being the effect of the right musical rhythm on Parkinson's patients: although normally "frozen", unable to initiate movement, they can suddenly dance with fluid motion when music of the right tempo is played. Rhythm, he reasons, seems to directly effect motor control centers in the brain stem, bypassing other motor controls i.e. the motor cortex.

So, I would examine the rhythmic aspect of rocking as the most likely source of it's ability to sooth.