EMPATHY AND PRO-SOCIAL
BEHAVIOR IN RATS
By Inbal Ben-Ami Bartal, Jean Decety and
Peggy Mason
Presented by
Anna Sherman-Weiss
What is being tested?
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Human Pro-Social Behavior is driven by
empathic concern for another. Is the same true
for non-primate mammals?
What is Pro-Social Behavior?
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The act of helping another being with no other motive
then to help
To “benefit other people or society as a whole”
What is empathy?
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Beyond basic level of emotional contagion
“Emotional response elicited by and congruent to with the
perceived welfare of an individual in distress”
Pro-social behavior is emphatically driven when the
emotional response can be down-graded so that it doesn’t
prevent the empathic being from helping the one in need
How is it being tested?
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Test 1: The effect of a trapped
cagemate on pro-social motivation
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Controls: Empty restrainer, restrainer with toy rat,
one rat with an empty restrainer separated from
another free rat by a perforated divider.
*Rats were housed together 2 weeks before testing
Test 2: The effect of an individual’s boldness
Test 3: The effect of anticipation of social interaction
Test 4: The relative value of liberating a cagemate (rat
vs chocolate chips)
https://vpn.mountsinai.org/VideoLab/1310979895001/,DanaInfo=video.sciencemag.org+1
What did they find?
Test 1:
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Average time to open the cage: 6.9±2.9 days
Rats with live cagemates moved faster and spent more time by the restrainer
– more motivated to assist a rat in need
Rats learned- number of rats opening the restrainers increased, the speed to
open the door decreased and the reaction to opening decreased with time
Rat activity increased after cagemate was freed  major event
Door-Opening Method
 1. Tipping door from side
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2. Tipping door from top
3. Pushing it with their heads
On days 6-12- only with head (anticipated a specific outcome
achieved by a deliberate tactic
What did they find?
Test 1 cont.
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Ultrasonic Vocalizations
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More alarm calls were recorded when a living cagemate was present
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More often in the beginning (20-27%) days 1-3
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Day 1: 90% of calls emitted by trapped, stressed rat, others are unidentifiable
Male vs Female
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A higher rate of female mice became
door openers (6/6 vs 17/24)
Female rats opened the restrainers
faster than males (days 7-12)
Female rats were more active than
males in only the trapped condition
Females more empathetic?
What did they find?
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Test 2: Individual Boldness
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Tested quickness to explore a half-opened cage prior to
testing
Correlation between the two – boldness is a possible
factor in pro-social behavior expression
What did they find?
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Test 3: Anticipation of
Social Interaction as a
Motive
Set-up: trapped animal could only exit into a different arena
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Step 1: Exposed to trapped condition
Step 2: Put in either an arena with an empty restrainer or a contained
(separate) cagemate
Step 3: Switched conditions
Exposed to separated cagemate: continued to open door at
same rate as trapped condition
Exposed to separated empty restrainer: stopped opening the
door
Opened cages with rats even without social contact suggesting it
is not a motive
What did they find?
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Test 4: The Relative Value of
Liberating a Cagemate (Rat vs
Chocolate)
Evaluated value of food reward: non-food-deprived rate ate an average
of >7 chips and no rat food
Chocolate/Cagemate Condition: No difference in the door-opening
latency for both restrainers (days 6-12)
Chocolate/Empty Condition: Opened chocolate faster
Suggested that chips and fellow rats are considered relatively equal.
Rats share!
 In 52% of all trials and 61% on days 6-12.
 When no cagemate, rat ate an average of 4.8± 0.7 chips out of 5
 With a cagemate, free rats ate 3.5±1.5 chips
What does it mean?
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Not enough rat alarm noises
to support the idea that the
rats just wanted to stop the
alarm calls
Curiosity wouldn’t have lasted a month
Latency to open the door decreased and it is not an easy
task making the reason of coincidence with high activity
seem unlikely
They conclude: rats free cagemates to end their personal
and/or peer’s distress. Emotional motive drives the prosocial behavior.
So what? Why is it important?
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Rats exhibit pro-social behavior when
they recognize a conspecific experiencing
nonpainful psychological restraint stress
and deliberately act to end that distress
(no training or rewards)
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Pro-social behavior helps to promote the well-being
of a population and gene pool
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A supportive community, taking care of each other
when an individual or group is in need, ensures
survival and the passing on of desirable genes
Concluding Questions
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What difference does it make if
non-primates have empathy as
well?
Does the difference between male and female rats’
opening rates make you consider the empathy and gender
any differently? Is it more nature than we realize?
What would the outcomes be if the rats had not become
been housed together two weeks prior to testing?
At a certain does this form of empathy go against natural
selection? (Freeing a stupid rat to make stupid rat babies,
not taking all the chocolate for oneself) Or is this altruistic,
pro-social action “a pact” guaranteeing a helpful
relationship in the future?
Bibliography
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http://changingminds.org/explanations/theories/prosocial_behavior.htm
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http://en.wikipedia.org/wiki/Prosocial_behavior