Lecture 6 Flashcards
What are the 5 layers of the general sensory hierachy
Receptors. Thalamic Nuclei. Primary Sensory Cortex. Secondary Sensory Cortex. Association Cortex.
Describe the general sensory hierachy
At the bottom are the receptors, which are the neurons that gather the information from the outside world and the body and send it to the thalamic nuclei. The primary sensory cortex then receives most of its input from the thalamic nuclei. From the primary sensory cortex information goes up to the secondary sensory cortex of the same system. Then the association cortex receives input from this, as well as from other sensory systems.
Define sensation
Process of detecting the presence of a stimulus.
Define perception
Higher-order process of integrating, recognising and interpreting sensations
What are the 6 most important parts of the eye
Pupils & Iris. Lens. Retina. Fovea. Blind spot. Optic nerve.
Where does light enter the eye
Through the pupil.
How is the size of the pupil regulated
By the iris, which is a band of contractile tissue.
Discuss the differences between pupil size
High illumination = small pupil.
Where does the light go and what does it do when it enters the pupil
Through the lens. Focuses incoming light on the retina & turns everything upside down
What is the job of the retina
It contains the receptors and four other types of neurons which are arranged in layers - the receptor cells are the innermost layer
What is the innermost layer of neurons
Receptor cells
What leave the eye in one bundle
Axons of the retinal ganglion cells.
What is the bundle (the eye) called
Optic nerve.
Why is there a blind spot
Because where the optic nerve leaves the eye there is a gap in the receptor layer, which is the blind spot.
Are we aware of the blind spot
Not usually, because the eye is constantly moving and the visual system will fill in the missing information from receptors that surround the blind spot.
