Learning and Memory

Question 1

Localization of Cognition and Emotion in Different Brain Structures (5):

Answer 1

1. Hypothalamus: primitive emotional responses
2. Frontal cortex: highest cognitive functions - control over emotions
3. Prefrontal cortex
4. Amygdala
5. Hippocampus

Question 2

What are the primitive emotional repsonses that the hypothalamus is responsible for? (4)

Answer 2

1. Fighting
2. Feeding
3. Fleeing
4. Mating

Question 3

Describe the relationship between the hypothalamus and the frontal cortex:

Answer 3

• Hypothalamus has a negative feedback response to the frontal cortex
  
  • impairs frontal cortex activity
  • “do not think clearly”
• Frontal cortex has a negative feedback on the hypothalamus

Question 4

What is the frontal cortex involved in?

Answer 4

• Judgment, Decision-­‐Making, Morality, Compassion, Responsibility
• Delayed and Slow Development
  
  • > 20 years to full maturity

Question 5

What part of learning is the prefrontal cortex involved in?

Answer 5

• Production and appreciation of art (beauty) as an emotion

Question 6

What is the function of the amygdala? What is its relationship with the frontal cortex?

Answer 6

• Function:
  
  • ​storage of emotional memories
• Relationship with Frontal Cortex:
  
  • ​negative feedback inhibition

Question 7

What is the role of the hippocamus?How do emotions affect the hippocampus?

Answer 7

storage of episodic memories

• activated or inhibited by emotionality
• necessary for us to remember the details of our lives
• highly susceptible to disruption by stress

Question 8

Synaptic plasticity:

Answer 8

• ability of synapses to change their strength in response to experience
• cellular model of learning and memory

Question 9

Glutamatergic receptors:

Answer 9

1. AMPA receptors:
   
   • basal synaptic transmission.
2. NMDA receptors:
   
   • blocked by Mg²⁺
   • Activated when the cells are depolarized
   • Important for synaptic plasticity

Question 10

Describe the cellular model for synaptic plasticity:

Answer 10

1. Presynaptic neuron is stimulated ⇒ releases excitatory neurotransmitter (Glu)
2. Glu travels to AMPA receptors on the postsynaptic neuron ⇒ causes membrane depolarization of postsynaptic neuron
3. Depolarization causes Mg²⁺ to dissociate from the NMDA receptors ⇒ NMDA receptors are now open
4. Open NMDA receptors allow Ca²⁺ influx ⇒ activates CaMKII or Calcineurin
   
   • CaMKII allows insertion of more AMPA receptors at the synapse (strenghten)
     
     • Long-term potentiation (LTP)
   • Calcineurin dissociates the AMPA receptors from the synapse (depression)
     
     • Long term depression (LTD)

Question 11

1. Long term potentiation (LTP):
2. Long term depression (LTD):

Answer 11

1. Long term potentiation (LTP):
   
   • ​enhancing synaptic strength
   • generated through changes in synaptic strength
   • operates in a network of neurons
   • pathway specific
   • varying durations
2. Long term depression (LTD):
   
   • ​​depressing synaptic strength

Question 12

What functions at the molecular level of learning?

Answer 12

1. CaMKII:
   
   • phosphorylates targets and important for LTP
2. Calcineurin (phosphatase):
   
   • dephosphorylates targets and important for LTD
3. ​Neurogranin
   
   • controls the synaptic plasticity balance
   • regulates of CaM availability

Question 13

How does aging affect learning and memory?

Answer 13

Aging is associated with synaptic plasticity imbalance and changes in the levels of important molecules

• Ex: CaMKII and calcineurin