Lecture 12, 13, & 14 (+crelox)

Question 1

What did Hebb postulate to be the neurobiology of memory?

Answer 1

Modified ensembles of neurons called cell assemblies could provide a substrate for memories

Question 2

How can neurobiologists study memory?

Answer 2

• Damage a particular region of the brain
• inject drugs into the brain that are designed to influence some aspect of neural function
• modify the DNA to increase or decrease the expression of some molecule

Question 3

What is the Morris Water-escape task?

Answer 3

Mouse dropped in the water and must find a hidden platform

Question 4

What are the two different temporal profiles of memory?

Answer 4

Short and long term

Question 5

What are the two states memory can exist in?

Answer 5

Active and inactive

Question 6

What are the two things you need to consider when trying to tell if a memory occurred or not?

Answer 6

Was it due to storage issue or a retrieval issue

Question 7

What are popular memory tests?

Answer 7

• inhibitory avoidance
• fear conditioning
• spatial learning
• recognition tasks

Question 8

What is inhibitory avoidance conditioning?

Answer 8

Zapping a mouse for doing something it wants to do (ex. Going into the dark or stepping down from a ledge) and seeing the latency of them doing it again shoot up

Question 9

What are some important attributes of Inhibitory Avoidance Training?

Answer 9

• only one trial is needed to produce a memory for this experience
• behavior is correlated with the intensity of the shock
• many modifications of this task

Question 10

What is fear conditioning?

Answer 10

Giving the mouse a cue (usually auditory or context) and then shocking them, and then playing the cue again and seeing how long the mouse freezes for (time thinking)

Question 11

What would be a spatial learning test?

Answer 11

Morris Water Test

Question 12

What are the measurements and important aspects of the Morris Water test?

Answer 12

• Measurement: escape latency, path length, probe trial, and search time
• visible platform test is done to ensure that the normal results are purely due to lack of memory

Question 13

What are recognition memory tasks?

Answer 13

• novel-object recognition
• object-place location
• object in context

Testing if the new items influence activity level

Question 14

What are some experimental approaches to the study of memory?

Answer 14

• stereotaxic surgery
• DREADDS
• genetic engineering
• optogenetics

Question 15

What is memory defined as?

Answer 15

An experience dependent alteration in behavior that persists beyond the original stimulus

Question 16

What are the stages of memory?

Answer 16

Encoding, consolidation, retrieval, and forgetting

Question 17

What are engram neurons?

Answer 17

Neurons that mediate a particular membrane across stages

Question 18

What behavioral tests did the Morris et al. Study use?

Answer 18

Administration of AP5 (NMDA antagonist) through a cannula and the Morris Water Maze

Question 19

What did the behavioral measures in Morris et al. Look into?

Answer 19

• latency to escape across the 10 days of behavioral training
• whether over training would allow rats to overcome NMDA blockade
• assessed whether a probe trails would show differences between rats with NMDA receptor blockade vs control

Question 20

What did the Morris et al. Paper suggest?

Answer 20

NMDA is critical to LTP induction and participate in the initiation of a memory

Question 21

How many subunits are NMDA composed of?

Answer 21

4

Question 22

What are the 2 classes of the NMDA subunits?

Answer 22

GluN1 and GluN2 (this one has hella subtypes like A, B, C, D, etc)

Question 23

What is the point of a Cre-loxP system?

Answer 23

To knock out or express a gene in specific cell types without affecting other cells in the body

Question 24

How do you breed the crelox mouse?

Answer 24

Round 1: Breed a cre mouse with a homozygous loxP flexed mouse -> cre and one chromosome floxed mouse
Round 2: breed the one chromosome floxed mouse with another homozygous floxed mouse -> homozygous floxed cre mouse

Question 25

What are the three possible things you can do with crelox?

Answer 25

Inversion deletion translocation