One important factor in acountryâs population density is its area. SouthAmerican countries, with their relatively largeland areas, tend to have low population densities.In Ecuador, the most densely populated country inSouth America, an average of only 118 peopleshare a square mile (46 people per sq. km).
Trochlear nerve: The nerve that controls the superior oblique muscle of the eye, one of the muscles that move the eye (extraocular muscles). Paralysis of the trochlear nerve results in rotation of the eyeball upward and outward (and, therefore, in double vision).The trochlear nerve is the fourth cranial nerve, and it is the only cranial nerve that arises from the back of the brain stem.aralysis of the trochlear nerve results in rotation of the eyeball upward and outward (and, therefore, in double vision). The trochlear nerve is the fourth cranial nerve, and it is the only cranial nerve that arises from the back of the brain stem.
Cranial Nerve 4. This is the trochlear nerve, which stimulates one of the eye muscles; namely, the superior oblique muscle. If this nerve has been damaged, when you move your eye to look towards your nose, you will not be able to move your eye downwards. Walking downstairs will give you double vision.