What is a sensory system and what does it do? What is the role of a sensory system in behavior? What are some things that a sensory system does not do?

Terms

Sensory Systems

• Input: Energy contains info about the world
  1. Accessory structure modifies energy
  2. Receptor transduces energy into a neural response
  3. Sensory nerves transfer the coded activity to the central nervous sys
  4. Thalamus processes and relays the neural response
  5. Cerebral cortex receives input abd produces the sensation and perception

Hearing

Vibration -> air molecules compression -> tympanic membrane transfer vibrate -> incus -> flow of the liquid in cochlea -> hair cell sense different freq of sound

Auditory System

• cochlea
• auditory nerve
• brainstem
• Thalamus
  • Medial geniculate nucleus
• auditory cortex

Somatosense

• Touch Receptors
  • Pressure
  • Indentation
  • Vibration
  • Stretch
• Pain receptors (nociception)
  • Pressure
  • Heat
  • Chemical
• Temperature receptors
  • Warm
  • Cold
• Proprioceptive - kinesthesia (body position)
  • Muscle stretch
  • Tendon stretch
  • Joint movement
• Proprioceptive - vestibular (balance)
  • Semi-circular canals (hair cells)

Smell and Taste

• Flavor: taste + smell
• Olfaction: Chemicals in the air
• Gustation: Chemicals in liquid

Taste

• Bitter
• Sour
• Salty
• Sweet

Pathway

• olfactory bulb -> olfactory (piriform) cortex
• taste buds -> 3 nerves -> thalamus -> insula (primary gustatory cortex)

Vision

• Two types of cell: Rod (monochrome) and Cone (RGB)
• Fovea: Small cones only
• Periphery: large cones & many rods