Sensory pathways

Question 1

What is the pathway of the visual system?

Answer 1

1. light falls on object
2. reflected wavelengths fall on eye (through lense on retina)
3. Via optical nerve (CN2) the information goes to the optic chiasm en splits to correct side of brain
4. Thalamus
5. Visual cortex in the back of the brain
6. Orbitofrontal cortex

Question 2

What is the pathway of the gustatory system?

Answer 2

1. TRCs on papillae on tongue
2. CN7,9,10
3. Nucleus of the solitary tract in the brainstem
4. Thalamus
5. Primary taste cortex
6. Orbitofrontal cortex

Question 3

What is the pathway of the olfactory system?

Answer 3

1. Odour molecules in air
2. Odour receptor cells (GPCRs) on nasal epithelium
3. Olfactory nerve (CN1) trough holes in base of skull
4. Correct glomerulus in olfactory bulb
5. Piriform cortex (primary olfactory cortex)
6. Orbitofrontal cortex

Question 4

What is the pathway of the trigeminal system?

Answer 4

1. receptors in nose, eyes and mouth
2. CN5
3. Brainstem
   4a. Insula 4b. primary somatosensory cortex
   5a. Orbitofrontal cortex 5b. Secundary somatosensory cortex