w2 Contrast Sensitivity Function

Question 1

what does CSF show and what does is describe

Answer 1

shows the envelope of sensitivity of several underlying mechanisms, describes the sensitivity of an observer to sinewave gratings as a function of their spatial frequency

Question 2

Why use sinewave gratings to investigate vision?

Answer 2

they help us understand how the eye and brain respond to different levels of detail and contrast. They’re simple, controlled patterns that make it easy to measure visual sensitivity, especially for things like contrast sensitivity and spatial frequency.

Question 3

Low frequency channels??

Answer 3

large objects gradual changes in intensity, overall shape but no fine detail

Question 4

high spatial frequency channels??

Answer 4

fine detail, these channels respond to the fine spatial structure of the world

Question 5

what is contrast sensitivity??

Answer 5

the ability to distinguish objects from their background based on differences in luminance

Question 6

How is contrast sensitivity different from visual acuity?

Answer 6

acuity measures the finest detail resolved at high contrast; contrast sensitivity measures ability to detect objects at various contrasts

Question 7

What does the Pelli-Robson chart measure?

Answer 7

contrast sensitivity

Question 8

Explain how contrast sensitivity function (CSF) curves differ in normal vs pathological eyes.

Answer 8

in pathological eyes (e.g. cataract) the CSF curve drops sharply showing reduced sensitivity especially at mid-to-high spatial frequencies