Questions
E2 Perception of stimuli
Neurobiology and Behaviour
1. Complete the table below to outline four main types of receptors and the stimuli they detect:
Receptor
Stimulus
Examples
Mechanoreceptor
Pressure
Texture
Vibration
Touch, pain and tension in skin
Touch receptors in skin
Inner ear for hearing and balance (1)
Thermoreceptor
Chemoreceptor
Photoreceptor
2. Label the structures of the human eye with their names and functions:
3. Label the section of the retina below:
4. Annotate the diagram below to outline how light stimulus is received by the photoreceptor and
converted to an action potential:
5. Compare rod and cone cells:
Rod cells
Cone cells
Light brightness
Diversity of cells
Wavelength sensitivity
Impulse: neuron ratio
distribution
6. Explain how visual stimuli are processed in the eye and brain, with reference to the following
stages (you can draw or find images to help, if you wish):
a. Image focusing and inversion in the cornea and retina
b. Visual fields
c. Contralateral processing and the role of the chiasma
d. The role and location of the visual cortex in the brain
e. Edge enhancement and ‘filling in’ of the blind spot
7. Label the diagram with the structures of the ear, and use the diagram to explain how sound is
perceived by the ear.
Further thought:
1. How does colour blindness work, from both a genetic and neurological perspective?
2. What are risk factors in hearing and vision loss and how can they be mitigated?
3. Research the use of stem cells and gene therapy in restoring vision to those who have been
blinded or who have blindness due to genetic factors.