Glutamate receptors required o AMPA receptors ligand gated ionotropic receptors

Glutamate receptors required o ampa receptors ligand

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Glutamate receptors requiredoAMPA receptors: ligand-gated, ionotropic receptors Na+ entersoNMDA receptors: same kind of receptor but also have a Mg2+ blocking the poreAllows Na+ & Ca2+ to enterCa2+ signals events necessary for LTP*AMPA receptors let Na+ into cell to repel the Mg2+ from the porePresynaptic changesoMore NT release oPresynaptic neuron expandsoInterneuron stimulates presynaptic neuron to release more NT’soNew synapses formedoDecrease threshold for AP’s (make them easier)Postsynaptic changes oPostsynaptic neuron expands, receiving more infoGas neurotransmitter involved in nitric oxide (NO)Alzheimer’s DiseaseSymptoms o1strecognizable symptom: mild anterograde amnesiaoGreatest risk factor: ageoDefining features: Plaques Tangles Neuron lossoDeficits in implicit & explicit memoryoDecline in attention oChange in personality Early vs. late onset ADoEarly has a STRONG genetic component
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Ex. Gene for APP (chromosome 21!)oLate is less clearAge (#1 risk factor)Lifestyle & previous head injurySome genetic involvement (usually beta amyloid)AD’s brainsoBrain atrophy (brain tissue shrinks)oLoss & malfunction of neuronsoLoss of spines & synapses; loss of connections b/w neuronsoMicrobleedsPlaques oLocated outside of cellsoMade by beta amyloidTangles oLocated inside of cells oFormed by protein tauVisionVisible SpectrumConsists of the electromagnetic spectrum Visible light the human eye can detectParts of eyeCornea: protective outer covering of eyeoFirst part of the eye that refracts light!Pupil: hole in the center of the iris that controls light entryoDilates in the dark, constricts in the lightLens: refracts light dramatically; changes to adjust focal distance (just like a camera!)oLens expands for short distance & flattens for long distanceoOlder people lose their ability to expand their lens (short)Retina: neural tissueoReceptor cells in retina transduce (convert) light into electrical signal to the brain via optic nerveRetina
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Neural signal travels back to front thru retinaoGanglion cells bipolar cells photoreceptors (rods & cones) Axons of retinal ganglion cells form optic nerve!Rods & ConesCones oLocated in center of retina (fovea)oHigh-acuity (central focus)oInvolved in color visionRods oPeripheral of the retina (outside fovea)oHigh-sensitivityRods are used to help you maneuver around a dark roomTransduction 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 PathwayOptic nerveoAxons of retinal ganglion cells Optic chiasmoOptic nerve converges (comes together)Optic tractoSame axons in optic nerve, but have passed thru optic chiasm (no synapse yet)Lateral Geniculate NucleusoPart of thalamus, SO, relay info to the cortexOptic radiationoAxons from LGN to primary visual cortexStriate cortexoFirst part of cortex to process visual info; become consciously awareoVisual world to the opposite hemisphereOccipital LobePrimary visual (striate) cortex is in the occipital lobe
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