Lecture 8: Behavioural Phenotyping in Mice

Question 1

limitations of animal models

Answer 1

• high cost
• modelling human behaviours is challenging
• not all findings generalizable

Question 2

properties of good animal test

Answer 2

• reliability
• predictive validity
• selectivity: test mostly reflects the appropriate behaviour

Question 3

Define predictive validity and face validity. Which is more important?

Answer 3

predictive - does the test predict human behaviour
face - does the test look similar to human behaviour

predictive validity is more important!!!! ex. the forced swim test obviously depressed humans wont drown but it does predict depressive behaviour.

Question 4

Elevated Plus Maze

Answer 4

EPM (tests anxiety)

• plus shaped maze with four arms (closed arms unexposed aka safe and open arms aka unsafe)
• measure time spent in each arm
• animals avoid open arms (indicator of anxiety)

Question 5

Object recognition test

Answer 5

OR test
three stages
1. training: animal is exposed to a set of identical objects
2. break: animal is removed from chamber (variable time)
3. Testing: animal returned to change and object replaced with a novel object

Question 6

Deletion of GABAa receptor subunit

Answer 6

• associated with depression like behaviour post partum (reduced maternal behaviour pups die)
• associated with poor performance at object recognition task

Question 7

testing working memory

Answer 7

• delayed response task

- y arm maze (radial maze, mice with good working memory remember where they are and dont go back there)

Question 8

Testing cognition

Answer 8

NOT the same as testing memory

- puzzle box

Question 9

Why are fear conditioning and object recognition used more commonly than morris water maze?

Answer 9

MWM is really labor intensive

Question 10

Tests for animal social behaviour

Answer 10

• three-chambered social interaction test (SIT)
• intruder test (for aggression)
• maternal behaviour

Question 11

SIT measures…

Answer 11

general sociability + social recognition/ social novelty preference (prefer novel mouse to familiar mouse).
- reduction in either suggests impairment in social behav.

Question 12

Probz with transgenic mouse models

Answer 12

• knocking out whole gene which is uncommon in nature
• knocking gene out from birth but studying in adulthood making mechanism by which it affects behaviour unclear (inducible models could solve this)
• sex bias (only men mouse)
• many tests done but only most interesting results reported
• compensation by other genes makes experiments difficult to interpret (is the knockout causing the effect or is it the overcompensation by another gene)
• different mouse strains exist and can affect outcome
• environments generally kept the same which RULES out gene-env interactions