Glutamate receptors required o ampa receptors ligand

 Glutamate receptors required
o AMPA receptors: ligand-gated, ionotropic receptors
 Na+ enters
o NMDA receptors: same kind of receptor but also have a Mg2+
blocking the pore
 Allows Na+ & Ca2+ to enter
 Ca2+ signals events necessary for LTP
 *AMPA receptors let Na+ into cell to repel the Mg2+ from the
pore
 Presynaptic changes
o More NT release
o Presynaptic neuron expands
o Interneuron stimulates presynaptic neuron to release more NT’s
o New synapses formed
o Decrease threshold for AP’s (make them easier)
 Postsynaptic changes
o Postsynaptic neuron expands, receiving more info
 Gas neurotransmitter involved in nitric oxide (NO)
Alzheimer’s Disease
 Symptoms
o 1 st recognizable symptom: mild anterograde amnesia
o Greatest risk factor: age
o Defining features:
 Plaques
 Tangles
 Neuron loss
o Deficits in implicit & explicit memory
o Decline in attention
o Change in personality
 Early vs. late onset AD
o Early has a STRONG genetic component

 Ex. Gene for APP (chromosome 21!)
o Late is less clear
 Age (#1 risk factor)
 Lifestyle & previous head injury
 Some genetic involvement (usually beta amyloid)
 AD’s brains
o Brain atrophy (brain tissue shrinks)
o Loss & malfunction of neurons
o Loss of spines & synapses; loss of connections b/w neurons
o Microbleeds
 Plaques
o Located outside of cells
o Made by beta amyloid
 Tangles
o Located inside of cells
o Formed by protein tau
Vision
Visible Spectrum
 Consists of the electromagnetic spectrum
 Visible light the human eye can detect
Parts of eye
 Cornea: protective outer covering of eye
o First part of the eye that refracts light!
 Pupil: hole in the center of the iris that controls light entry
o Dilates in the dark, constricts in the light
 Lens: refracts light dramatically ; changes to adjust focal distance (just like a
camera!)
o Lens expands for short distance & flattens for long distance
o Older people lose their ability to expand their lens (short)
 Retina: neural tissue
o Receptor cells in retina transduce (convert) light into electrical signal
to the brain via optic nerve
Retina

 Neural signal travels back to front thru retina
o Ganglion cells  bipolar cells  photoreceptors (rods & cones)
 Axons of retinal ganglion cells form optic nerve!
Rods & Cones
 Cones
o Located in center of retina (fovea)
o High-acuity (central focus)
o Involved in color vision
 Rods
o Peripheral of the retina (outside fovea)
o High-sensitivity
 Rods are used to help you maneuver around a dark room
Transduction
 Process that we convert physical energy in the world (light/photons) into
electrical signals (like AP’s)
 Receptor cells (rods & cones) interact w/ stimulus, causing change in neural
activity (transduction)
Visual Pathway
 Optic nerve
o Axons of retinal ganglion cells
 Optic chiasm
o Optic nerve converges (comes together)
 Optic tract
o Same axons in optic nerve, but have passed thru optic chiasm (no
synapse yet)
 Lateral Geniculate Nucleus
o Part of thalamus, SO, relay info to the cortex
 Optic radiation
o Axons from LGN to primary visual cortex
 Striate cortex
o First part of cortex to process visual info; become consciously aware
o Visual world to the opposite hemisphere
Occipital Lobe
 Primary visual (striate) cortex is in the occipital lobe
