*Neurons that detect a particular category of physical events.
*Process by which sensory stimuli are transduced into slow, graded receptor
*Slow, graded electrical potential produced by receptors in response to physical
*Actual electronic potential that happens in Sensory transduction
*Perceptual dimensions of colour
*Hue – the dominant wavelength; the color of the light that’s coming into the eye
*Shorter wavelengths – bluish – violet colors
*Longer ones – reddish color
*Perceptual dimensions of colour
*Brightness – intensity; increase in brightness, increase in intensity
*Saturation – purity; increase in saturation, increase in wavelengths
*Vergence – cooperative eye movements, ensures the image falls on identical
portions of each retina.
*Convergence (looking towards the same point) vs. Divergence (looking
into different directions)
*Saccades – rapid, ballistic eye movements (video, moving back and forth eye)
*Overt attention – bring power of fovea to bear on objects
*Smooth Pursuit – eye movements tracking a moving object.
*Three of twelve cranial nerves dedicated to controlling eye movements (oculomotor,
Eye movements that compensate for head movements
Nystagmus – alternating smooth pursuit in one direction followed by saccades in the opposite direction
*Anatomy of the Eye
*Ciliary Muscles – control the shape of the lens.
**They didn’t work for older peoplehyperopia
*Accommodation – changes in thickness of the lens, accomplished by the
ciliary muscles, focuses images of near or distant objects on the retina.
*Photoreceptors – transduces photic energy into electrical potentials.
*Rods – sensitive to light of low intensity; sensitive to light, changes in contrast,
movement and motion; used for night visions
*Cones – maximally sensitive distinct wavelengths; encodes color.
*receptors sensitive to color; very sensitive to different wavelengths or light;
where your details come from
*Fovea – region of the retina that processes central 4 to 6° of vision.;
*Cones the only photoreceptor found in the fovea
*Bipolar Cells – middle layer of retina, conveying information from
photoreceptors to ganglion cells.
*Blue one – horizontal cell – connects adjacent rods and cones; connects
them and aggravates and make them function as one giant receptor
*Ganglion Cells – conveys information from bipolar cells to brain via the optic
*Not important: Horizontal Cells – interconnects adjacent photoreceptors and
the outer processes of bipolar cells; connects the rods and cones and
connects them all and makes one big receptor
*Amacrine Cells – interconnects adjacent ganglion cells and the inner
processes of bipolar cells.
*Optic disc and the blind spot – where your optic nerve
*The brain fills in the missing info in the blind spot
*We’re not aware of our blind spots
*Lamellae – layers containing photopigments.
*Photopigment – protein dye bonded to retinal (a lipid) responsible for transduction
of visual information.
*Opsin – class of protein that act as a photopigment.
*Retinal – chemical synthesized from vitamin A that acts as a photopigment
Change Blindness We do not have a full and complete representation of everything we see!
Change blindness- you’re not aware of the things that you’re not paying attention to
From Eye to Brain
*Dorsal Lateral Geniculate Nucleus (LGN)