Orientation

Question	Answer
Give the three main contributors to orientation.	Visual, vestibule and proprioception
Why cant we just use vision as method of orientation? What other system do we require?	We dont know if its our body moving or the world moving, the vestibular system tells us if we are moving.
Give the names of the three semi-circular canals.	Anterior canal, posterior canal and the horizontal canal.
What do the otolith organs allow us to respond to?	Tilt and acceleration
Describe the structure of the otolith organ.	A calcified gelatinous structure with mass which sits on some hair cells.
When we combine information from our semicircular canals to keep our eyes looking where we want this is called the ...	Vestibulo-ocular reflex
There are two theories which explain how we know if our eyes are moving or we are moving. What did Sherrington and Helmholotz each suggest. which is believed to now be correct?	Sherrington thought that we receives information from our muscle spindles which then allow our brain to know either our eyes are moving. Helmholtz disagreed and said it was due to efferent copying from the brain so we knew when we were about to move our eyes. Helmholtz theory is thought to be correct on the reasoning that if we move our eye externally e.g. with our finger our vision blurs.

Resource summary

	Created by alexlpeart almost 11 years ago