PSYC234 Study Guide - Final Guide: Distance Fog, Circadian Rhythm, Binocular Disparity
Sensory Systems
-Hierarchical functionality homogeneous serial!
• (diagram)!
•Hierarchical in two ways as sensory info ‘flows’ through brain because sensation is
less complex than perception!
-Sensation = simple process of detecting presence of stimuli!
-Perception = complex process of integrating, recognising and interpreting sensations!
Vision!
-Process of light entering eyes which makes light essential for vision!
-Properties of light are wavelength (colour) and intensity (brightness)!
-Cornea!
•Contains no blood vessels!
•clear dome shaped surface covering front of the eye!
•Helps focus vision —> 65-70% of focusing power!
•Acts as a barrier against things that can harm the eye!
-Iris !
•Regulates light input!
•Think circular structure which controls diameter and size of pupil which regulates
how much lights enters the eye!
•Eye colour is defined by this!
-Pupil!
•Opening at centre of the iris!
•Size controlled by ciliary muscles!
•In darkness pupil is bigger, in brightness pupil is smaller!
-Lens!
•Focuses light on the retina (accomodation)!
•Helps refract light to be focused on in retina!
•Changes shape which changes focal distance of eye so it can see things at different
distances!
-Retina!
•Has 5 layers!
•Senses light!
•Light sensitive tissue at back of the eye!
•Converts light into electrical impulses which are sent to brain through optic nerve!
-Fovea!
•Small pit at surface of retina!
•Allows light to be sensed without any dispersion/loss!
-Optic disk!
•Point of exit for ganglion cell axons leaving eye!
•Represents beginning of/is entry point for optic nerve!
-Cells of retina !
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-Blindspot occurs where axons pass over front of retina!
-Rods and cones!
•Are receptors!
•Function by graded, not action potential!
•Cones are most dense in fovea!
•Rods found in periphery!
•Have more rods than cones (20:1) but cones provide 90% of the brains input !
•Cones allow us to see in colour!
-Third photoreceptor!
•Melanopism!
•Not just rods and cones!
•Come cells in retina contain this!
•Responsible for 24 hour body clock (as it is based on light)!
Document Summary
Hierarchical functionality homogeneous serial: (diagram, hierarchical in two ways as sensory info ows" through brain because sensation is less complex than perception. Sensation = simple process of detecting presence of stimuli. Perception = complex process of integrating, recognising and interpreting sensations. Process of light entering eyes which makes light essential for vision. Properties of light are wavelength (colour) and intensity (brightness) Cornea: contains no blood vessels, clear dome shaped surface covering front of the eye, helps focus vision > 65-70% of focusing power, acts as a barrier against things that can harm the eye. Iris: regulates light input, think circular structure which controls diameter and size of pupil which regulates how much lights enters the eye, eye colour is de ned by this. Pupil: opening at centre of the iris, size controlled by ciliary muscles, in darkness pupil is bigger, in brightness pupil is smaller.
