4.2 Sensation and Perception

Sensation: Convert physical properties into neural signals.

• Vision: Light entering the eye
• Audition: Vibrations in the air entering the ear canal
• Tactile (touch): Pressure and heat on the skin
• Olfaction (smell): Airborne chemical compounds in the nasal passage
• Gustation (taste): Chemical compounds in the mouth

Internal Senses: Senses that measure body state.

• Proprioception: Sense where our limbs are in space.
• Nociception: Sense of pain due to bodily damage.
• Equilibrioception: Sense of balance.

Perception: Processing of sensory data into meaningful info about our environment.

• Inference - Guessing the properties of the world that caused the sensory stimulation.
  • The sensory stimulus is ambiguous: It's only measurements of the object

Visual Illusions

Illusions: Reveal underlying assumptions that the brain makes during perception.

Lightness: How light or dark a surface is.

Reflectance: How much light a surface reflect

Visual System

Eye Structure

From outermost to innermost:

1. Cornea: Transparent, rubbery layer of tissue at the front of the eye.
2. Iris: Circular ring of colored muscle.