Animal Cognition

Clive D. L. Wynne

Lecture 4Cause & EffectReasoning

Cause and Effect Learning

Pavlovian conditioning

Aka, Classical, Respondent or Type II conditioning

Ivan P. Pavlov 1849-1936

Already famous as physiologist studying digestion

• Noticed dogs would salivate to sight of scientist – ‘Psychic secretions’

Pavlov’s dogs Originally

Put food in dog’s mouth Dog salivates

After doing this a few times Dog salivates just when it senses that

food is going to be put in mouth

Classical conditioning

A process by which an initially neutral stimulus (the conditioned stimulus, CS) comes to produce a response (the conditioned response, CR) through being repeatedly paired with a stimulus (the unconditioned stimulus, US) that produces a response prior to training (the unconditioned response, UR).

Classical conditioning Food Salivation

US UR Metronome No salivation

CS -Conditioning… Metronome: Food Salivation

CS URAfter conditioning… Metronome Salivation

CS UR

Pavlovian terminology Unconditioned Stimulus (US) –

stimulus that produces a response prior to training

Unconditioned response (UR) – response to the US, occurs prior to training

Conditioned stimulus (CS) – initially neutral stimulus

Conditioned response (CR) – response to the CS that only develops after CS and US have been repeatedly paired.

Pavlovian procedures

Before conditioning Conditioning After conditioning

US-food

in mouth

UCR

salivation

CS-tone Orientation

but no

salivation

US-food

in mouth

UCR

salivationUS-food

in mouth

UCR

salivation

CR

salivationCS-toneCS-tone

Conditioned Flavor Aversions

Eat something Feel sick Avoid that flavor in future

CFA Experiment

Foot shockBright-noisy

waterGroup A

Group B

Group C

Group D

Bright-noisy

water

Tasty

water

Tasty

water

Sickness

Foot shock

Sickness

Group Stimulus Outcome Test water

Avoid

OK

OK

Avoid

CFA Experiment Some consequences can be more

readily associated with certain stimuli

Interval between CS and US can be very long

Common experience is a form of learning

Functions of CRs Prefiguring

CRs enable individual to optimize interaction with upcoming US.

Evidence in favor: Dog saliva has different composition

CR saliva is thinner than UR – prepares digestive system

Rats jump to shock US: freeze to CS Jump if snake attacks; freeze if snake

detected

Functions of CRs Predator defense CSs that predict danger USs evoke

predator defense reactions Rats turn and flee from danger CS But will freeze if learn that there is

no place to run to Autonomic responses: increase

heart rate etc.

Diversity of Pavlovian cond.

Animals learn about what predicts what Paramecia lean to withdraw when vibrations

are followed by electric shock Honeybees associate odors, colors & shapes

with sucrose; but not with escape from box. Marine snails (aplysia) associate light

mantle touch with shock to tail (close gill flap)

Lemon sharks learn to blink to light that predicts mild shock close to eye – likewise goldfish.

Diversity of Pavlovian cond.

Siamese fighting fish attack own reflection. Conditioned to attack red light.

Leopard frogs conditioned to blink to light tough on nostril followed by touch on eye – also toads

Bengal monitor lizards conditioned with flickering light CS to food US attacked the light.

Collared lizards changed breathing, pulse and leg movements in response to sound and light that preceded electric shock.

Birds: especially pigeons Mammals: especially rats, mice, rabbits, dogs &

humans; also cats and marsupials.

Diversity of Pavlovian cond.

Hollis et al., 1997. Male blue gouramis attack intruder males

and may repel egg-bearing females Males exposed to 10-s white light followed by

5-min exposure to female fish. Came to make mating displays to light – were

better prepared for female – less aggressive. At end of experiment Experimental group

males had sired > 1000 offspring each. Control group < 50 offspring each.

Behavioral Consequences

In Pavlovian Conditioning behavior is elicited by stimuli (CR and UR)

But often behavior is controlled by its consequences

Operant behavior The behavior operates on the

environment A.k.a. instrumental conditioning

The behavior is instrumental in achieving some consequence.

Edward Thorndike (1874-1949) Put animals in boxes and watched

how long it took them to escape Essentially random behavior Learning by trial and error

Thorndike’s Puzzle Boxes

Thorndike’s law of effect Consequences of an act determine

whether it will be repeated in the future

Behaviors followed by positive consequences are more likely to be repeated – strengthened – stamped in

Behaviors followed by negative consequences are less likely to be repeated – weakened – stamped out

Small’s Hampton Court Maze

Modern mazes

Skinner’s Learning by Consequences

Free Operant techniqueFree Operant technique SubjectSubject free free to make to make

response at any time – not response at any time – not driven by reflex or structure driven by reflex or structure of apparatus (e.g., maze).of apparatus (e.g., maze).

Operant conditioningOperant conditioning Type of learning where Type of learning where

future probability of a future probability of a behavior is affected by its behavior is affected by its consequencesconsequences

Skinner’s Learning by Consequences

More difficult to operant condition than Pavlovian because of need to find suitable reinforcement v. difficult to operant cond. cold-blooded animals.

Tadpoles learnt to move away from a light to avoid a shock Anoles (lizards) learnt to escape shock by running to

another part of apparatus – also collard lizards and desert iguanas

Queen triggerfish pressed plastic rod to drop food into tank – also goldfish & koi carp

Birds: pigeons; doves; chickens; gulls & quail Mammals: rats, mice, rabbits, cats, dogs, raccoons, skunks,

ferrets, minks, farm animals, marsupials, primates, humans.

Diversity of Operant cond.

Reasoning

Spatial Reasoning Tolman &

Honzig, 1930 3 paths –

blockable at points shown.

Once familiar with the maze, rats always chose the shortest remaining path after a blockage

Spatial Reasoning Wolfgang Köhler, 1925 Transparent barriers (fence of wire netting) Dog, girl just > 1 yr, chickens, chimpanzees

start

goal

Spatial Reasoning

Bruno Poucet et al., 1983 Cats choose shorter path But only if barrier opaque. In extended tests cats only take shorter

route if does not involve larger original detour angle.

Reasoning about Gravity Hood et al.,

1999

Insight Wolfgang Köhler,

1921 Chimpanzees on

Tenerife in WW1 Banana hung out of

reach on roof Köhler impressed

by the flash of insight

All six apes vainly endeavored to reach the fruit by leaping up from the ground. Sultan soon relinquished this attempt, paced restlessly up and down, suddenly stood still in front of the box, seized it, tipped it hastily straight towards the objective, but began to climb upon it at a (horizontal) distance of ½ meter, and springing upwards with all his force, tore down the banana.

More Insight

Pigeon Insight Robert Epstein et al., 1984 Pigeon reinforced for moving

box to a green spot in the center of the chamber

On other trials for standing on a box already placed in the center of the chamber and pecking at the plastic banana hanging from the ceiling.

In test session pigeon was faced with the problem of pecking the banana while the box was at the side of the chamber and there was no green spot to move the box to. Pigeon quickly solved the problem by moving the box to the center of the chamber and mounting it to peck the banana.

Insight Elisabetta

Visalberghi & Luca Limongelli, 1994

Only 1 of 4 Capuchins learnt to avoid the trap over 140 trials.

When trap was inverted still treated it as dangerous.

2 of 5 chimps successful Only 1 chimp behaved

appropriately when the trap was moved up and down the tube.

Tool use Ant-lions throw sand on

prey that comes in their pits Japanese macaques use

water to separate sand from food grains

Open mollusk shells Sea otter smash them on

stones held against their chests

Gulls drop them onto stones from a height

Hermit crabs grab sea anemones and use them to repel enemies

Tool use/creation Tetsuro Matsuzawa.

Bossou chimpanzees hammer/anvil nut cracking 1 on map

Other chimp communities have different tools

Termite fishing

Water sponge

Tool creation

Bryant & Trabasso (1974)

Series Reasoning: Transitive Inferences

Kate is cleverer than May: May is cleverer than Jane.Who is the cleverest--Jane, Kate or May ?

Children

A

B

CD

E

McGonigle & Chalmers (1977)

NON-REWARDEDREWARDED

Squirrel Monkeys

+ -

+

+

+

-

-

-

Pigeon Stimuli

+ -

Pigeon Data

50.00

60.00

70.00

80.00

90.00

100.00

A+B-

B+C-

C+D-

D+E-

A+B-

B+C-

C+D-

D+E-

X+A-

A+B-

B+C-

C+D-

D+E-

E+F-

X+A-

A+B-

B+C-

C+D-

D+E-

E+F-

F+X-

Pair/ Phase

Per

cent

cor

rect

res

pons

es

Pigeons Model

Phase 1 Phase 2 Phase 3 Phase 4

Counting: Sheba (chimp)