The Visual Brain

Question 1

Which eye part is the central part of the retina where cones are densely packed with very few rods in this area?

Answer 1

The fovea

Question 2

Which eye part has an area which includes the number of cones decreasing, and the number of rods increasing?
This leads to this area being dominated by rods, which are more sensitive to low light and motion but do not provide detailed or colour vision?

Answer 2

Peripheral Retina

Question 3

What is the optic disc, where the optic nerve exits the eye, contains no photoreceptors which blocks a part of our vision also known as?

Answer 3

The blind spot

Question 4

There are no rods at fovea, their peak density is at around how many degrees eccentricity?

Answer 4

15 degrees

Question 5

Cones have the highest density at fovea, but some in … regions of retina?

Answer 5

peripheral

Question 6

During dark adaptation, there is a gradual increase in photoceptor sensitivity over time.

What are the main distinct parts of this functional change?

Answer 6

2 distinct branches, due to the transition from cones to rods

Cone sensitivity: initially more sensitive (until 5-10 minutes)

Then switch to Rod sensitivity

Time in which this actually switches is known as Rod-cone break

Question 7

The process of switching from using cone to rod sensitivity during dark adaptation is known as?

Answer 7

Rod-cone break

Question 8

During the process of Rod-cone break:
… sensitivity adjustment takes 4-5 minutes
… sensitivity adjustment takes 20-30 minutes
To reach the maximum

Answer 8

Cone= 4-5
Rod= 20-30