MSU PSY 209 Final Exam

Psy 209 final review session 


Divisions of the nervous system 

  • CNS

    • Forebrain 

      • Telencephalon

        • Cortex

        • Basal ganglia

        • Limbic system

      • Diencephalon

        • Thalamus

        • hypothalamus

    • Mesencephalon (Midbrain) 

    • Hindbrain (brainstem)

      • Metencephalon

        • Cerebellum

        • Pons

      • Myelencephalon (medulla) 


Resting potential

  • Reflects balance between diffusion and electrostatic pressure

  • Diffusion = diffusion of ions through ion channel

    • Na+ 

      • Sodium 

    • K+

      • Potassium

  • How do the forces drive the resting potential 

    • Diffusion

      • The idea that if the situation allows it, ions will tend to go from high concentration to low 

      • Only sodium can diffuse during resting state 

  • During resting potential, certain ions pass more freely than others

  • Membrane permeability

    • Membrane of a cell separates the interior from the exterior and can be selectively permeable (ex via ion channels) to chemicals allowing movement of substances in and out 

    • Channels only opened if cell is being stimulated

      • Leak potassium channels are open, though 

  • Electrostatic pressure = distribution of electrical charges 

    • Repells if they are like, but polarities are opposite then they attract 

    • Mediates resting potential 

    • The machinery that maintains the resting potential is the sodium-pottasium pump = mechanism that pushes sodium out of the cell and potassium into the cell 

      • Potassium can move, sodium cant

  • Neuron at rest is in negatively charged state 

    • -60 mV relative to the outside of the cell 

      • Extracellular fluid


Feeding and satiety

  • VMH

    • Ventromedial hypothalamus 

  • LH

    • Lateral hypothalamus 

    • If you get rid of this, you get rid of the feeding response 

      • Necessary for feeding 


Homeostasis

  • Need to determine our energy state, respond to that state


Plasticity and learning 

  • Following LTP (long term potentiation) increase in AMPA receptors increases the synaptic sensitivity to glutamate 

  • The greater the number, the more excitation the neuron is feeling (of LTP number)

    • Can increase as the two neurons communicate, and stays increased so that when the neuron/s fire onto the neuron, the same electrical charge is expected to be present 


Before 

  • What is a primary neurotransmitter responsible for in long term potentiaiton 

    • Glutamate is abundant in all of our brains (90% have some sort of glutamatergic signal)

      • Acts as a stimulatory, excitatory signal (first role)

      • Acts predominantly as a stimulant, or driving excitatory factor 

    • Gaba is the opposite

      • Acts as inhibition of brain activity 

  • NMDA receptor

    • Glutamate can’t do anything to it; magnesium is blocking it

    • In the before stage and post synaptic neuron, not enough charge for the magnesium to stop blocking it 


During 

  • Calcium enters the cell

    • Activates something called campK2

      • Tells cell to do stuff; alters chemistry of the cell so that it is more able to fire more strongly in the future 

  • What does it do to AMPA receptors 

  • Calcium told campK2 that they want to push AMPA receptors up to the surface of the postsynaptic membrane 

  • AMPA receptors get pushed back; go from after to more like before (AMPA goes back into the neuron, and doesn’t have same opportunity to show EPSPs), which results in us forgetting information 


Before vs after figures differences

  • Extra AMPA receptor 

    • Allows the next time the presynaptic cell releases glutamate, more excitatory post synaptic potential 

    • Happens with lots of receptors and lots of neurons 


Psy 209 

  • Specific receptor that drive hallucinations 

  • Taste systems, one was salt. What are the channels that allow you to detect salty foods 

  • Anatomical terms 

    • Horizontal planes, if you were to cut through the brain in a certain way, what fields would be shown 

  • Inhibitory post synaptic potential 

    • Hyper polarization, neurons are likely going to fire less if they are in a state where they are bombardier with IPSPs bc they’re more negative, how do we get them (bc we get the buildup of negative ions into the cell)

  • Drugs

    • Can kill, emphasize from toxicity dose and lethal dose 

    • Lethal dose 50 - telling us basically at this dose 50% of the population will die if they take the drug at this dose 

  • Who coined the term cells that fire together wire together 

  • Colonergic system 

    • Two types of receptors 

      • Muscerinic 

      • Nicotonic

  • What does the cerebral spinal fluid do

  • Labeling of the brain 

  • Use of identify in those brain cells the dna sequence of what the cell expressed 

    • If its serotonin expressing, it’ll have gene code for serotonin, use a technique of ISH to look for just that potential genetic signature, and will label the cell and tell us everything we need to know (ex)

      • ISH uses dna of cell to label cell 

    • Cells aren’t just genetically able to produce it, a serotonin cell has serotonin dna, but a serotonin cell produces serotonin the protien; other approach - doesn’t look for dna itself but the protien 

      • Amino cyto chemistry approach?

  • Optogenetics

    • How do you stimulate cells w it

  • Glutamatergic pyramidal cells

    • Pyramidal cells in cortex

  • Phineas gage 

  • Estimated number of synapses in the brain

  • Tracing techniques 

    • Anterograde tracer 

      • Move foward

      • Place in amygdala

    • Retrograde tracer 

      • Moved backwards 

      • Place in pfc

  • Describing the neuron

    • Axonal terminal: what does it do

  • Basal ganglia: what are the areas of the brain that contain it 

  • Major inhibitory neurotransmitter 

    • GABA; allows negatively charged chloride into the cell 

Development 

  • How does the process of cell differentiation work 

    • How does a cell become a dopamine cell, ex 

  • Which neurotransmitter system is associated with Parkinson’s 

  • How many chromosomes do humans possess? 23 pairs

  • The signals in the gut that make us hungry: ghrelin

  • Leptin makes us feel full/stops us from eating 

Epigenetics 

  • DNA methylation and just one modification 

  • Cell death - apoptosis 

    • What limits apoptosis, why do certain cells come to it and others don’t 

    • Related to nutrients the cells receive: neurotropic factors are how they receive 

  • Saltatory conduction 

  • Which drug blocks the transporters for cathacholamines 

    • Dopamine transporter 

      • Illicit stimulant 

  • Fear learning 

    • Model in the lab 

    • Idea of conditioning

    • What are the brain mechanisms controlling it 

      • Not just amygdala, but two subdivisions 

        • Central nucleus (encoding) and basal lateral (allowing expression)

  • Cranial nerves that send taste into

    • 7, 9, 10?

  • What drug did they apply in chanters cognitive attribution model 

    • Epinephrine 

  • What would happen if you disrupt activity of the t1r2 receptor 

    • Can’t taste sweet 

  • Positive symptoms of schizophrenia 

    • Delusions, hallucinations