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Flashcards in Measures of Aversion Deck (19)
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1
Q

Give examples of real-life scenarios involving aversive stimuli which must be investigated

A

Euthanasia of lab rodents Transport/handling of farm animals Conditions that lead to pain (not nociception) Pharmacology

2
Q

What technique is used to prevent having to re-use the aversive stimuli in a lab test?

A

Aversion learning - may be classical or operant avoidance

3
Q

What is classical aversion learning?

A

Conditioned supression

4
Q

What are the two types of instrumental avoidance learning?

A

Active and passive

5
Q

What is conditioned suppression?

A

Positively reinforced task is taught (operantly) eg. peck for food Inescapable aversive stimulus presented immediately after warning signal (classical conditioning)Extent to which baseline task is suppressed is taken as a degree of aversion

6
Q

Give an example of a baseline task used for humans to show classical conditioned suppression

A

moving disks from one spike to the next Salgado et al. 2000Conditioned stimulus = tone, Unconditioned stimulus = loud noise

7
Q

How is the suppression ratio calculated?

A

a/(a+b) a=rate of activity during CSb=rate of lever pressing prior to CS Ratio of 0.5 indicates no suppression

8
Q

What are the problems associated with using conditioned suppression as a measure of aversion?

A

Not ethical! Not sure why suppression occurs as doesn’t prevent aversive stimuli May be inappropriate for some speices Sensitivity in doubt - response may be all or nothing so no gradated Learned helplessness can occur

9
Q

Is conditioned suppression used by welfare scientists?

A

No, only learning theory investigation

10
Q

How does active instrumental avoidance work?

A

Animal trained to perform a response to avoid exposure to aversive stimulus NEGATIVE REINFORCEMENT consistency and speed of task performance indicates degree of aversion

11
Q

What are the problems associated with active instrumental avoidance techniques?

A

Species-specific responses to fear Animals may freeze Can only assess effects of immediate stressors (ie. not heat or subtle environmental changes)

12
Q

Give an example of active instrumental avoidance

A

Rutter and Duncan 1991 - hens run from one side of box to the other to escape suddenly inflated balloon Light predicted thisHens DID NOT learn this predictor

13
Q

What is PASSIVE operant or instrumental avoidance?

A

Animals learn not to perform a behaviour to avoid exposure to an aversive stimulus Punishment Consistency and speed of response inhibition indicates degree of aversion Most common in welfare science

14
Q

What is the commonest way of measuring aversion in welfare science?

A

Passive operant or instrumental avoidance

15
Q

Give four examples of passive operant avoidance

A
  • Rushden 1996 - sheep run through a race and subjected to different treatments Latency measured (learnt not to perform the running through race response in order to avoid shearing or handling)- Zebra fish aversion to anaesthetics - put into test chamber and see where fish move to - moved out of MS222 and benzocaine, two agents identified that were non aversive - Makowska and Weary 2007,8,9 - rodent euthanasia agents - had to go down into a different chamber to get food - Nasr 2013 - testing for longer duration aversive states (keel fractures) - conditioned place preference/aversion
16
Q

What is necessary when measuring aversion?

A

A common currency to compare different aversive stimuli

17
Q

Who came up with criteria for a common currency method?What were they?

A

Abeyesinghe et al 2000 - repsonse compatible with species behaviour - method equally appropriate for all stressors being evaluated - method allows comparison over different time periods eg. immediate vibration stress v. heat stress - sufficiently sensitive to measure within-stressor (magnitude) and between - stressor differences - accurate, repeatable and robust

18
Q

What method allows multiple stressors to be compared at once?

A

Simultaneous choice

19
Q

Give 3 practical findings based on aversion measurement

A

Electro-immobilisation - more aversion than physical restraint, banned 1990 UK Sheep restraint - prefer to be in visual contact with other sheep and educating stockmen that animals remember poor/inconsistent handling for a long time Pharmacology and learning ability -most tests are not done to evaluate the aversiveness of a situation but rather assume the stimulus to be aversive