How does the eye transduce (transform) light energy into
neural messages?
• cornea – outer layer/
protects the eye
• pupil – small black opening
• iris – colored muscle,
expands & contracts to let
light into the pupil
• lens – focuses light onto
the retina, changes its
curvature (accommodation)
How does the eye transduce (transform) light energy into
neural messages?
• retina – tissue of the inner
eye which contains the
rods and cones
• blind spot – a spot where
there are no rods or cones,
where the optic nerve
leaves the eye
• optic nerve – carries
information to the brain
Blind Spot – area of the retina where the
optic nerve leaves the eye
and Cones
• aka: photoreceptor cells
• aka: sensory cells
• where energy transduction
(transformation occurs)
• ratio = 20:1 (rods to cones)
Rods and Cones
Rods
Cones
• Cones –function in
daylight, or well-lit
conditions. The
cones detect fine
detail color.
Cones = Color
• the fovea is the center
most part of the retina
• responsible for our
central, sharpest vision
• key for reading,
watching television,
driving, and other
activities that require
the ability to see fine
detail
• very high
concentration of cones
Peripheral Vision Demonstration