In today's lecture we will first complete our discussion of the auditory system, discuss some issues in psychophysics (measurement of sensory thresholds) and then focus on a discussion of the visual system, including its structure and basic operation, and then the higher level processes by which it extracts information from the world.

The slides for today are the same as those of Tuesday and are here.

• Psychophysics, the relation between the physical world and what is sensed.
• ---Measuring sensory thresholds
• ---Weber's Law
• ---Fechner's extension of Weber's Law
• ---Steven's power function
• The structure and function of the eye.
• The centrality and importance of the retina.
• Some operating characteristics of the eye (sensitivity, acuity, adaptation, etc.).
• Duplex theory of vision (two visual systems).
• Lateral inhibition and a focus on sensing spatial and temporal change in the world.
• The analysis of visual inputs--some brain functions in feature detection.
• Top-down and bottom-up processes in perception.