Test

Research methods, learning, evolutionary, developmental

Define “Learning”

 a situation where there are relatively long lasting changes in behaviour, and these changes are caused by environmental events (maturation, drugs, surgery)

Describe the Law of Effect

If a response is followed by a favourable consequence, the behaviour is more likely to occur again

• E.g. if a cat in Thorndike’s puzzle box pulls the rope (response) & escapes (reiforcer), it’ll be more likely to pull rope again
  
  Reinforcement most effective if it immediately follows response 

  • Guaranteed by arranging contingency between response & reinforcement

Define “extinction”

If a response used to be followed by reinforcement, but reinforcement stops, it will be less likely to happen again

Describe feedback interaction

Example: trying to cook dinner but the kids are fighting - turn on TV to keep them quiet

• My behaviour: negatively reinforced by removal of aversive stimulus (noisy fighting kids)

• Kids’ behaviour: positively reinforced by presentation of appetitive stimulus (TV)

There’s a feedback interaction – you can’t change someone else’s behaviour without your own also changing

What is primary reinforcement?

reinforces behaviour because of their innate biological significance 

• Food, warmth, safety etc

What is secondary reinforcement?

previously neutral stimuli that have acquired reinforcing properties by being paired with primary reinforcers in organism’s history

• Sound of food pellets, praise, money etc

What is continuous reinforcement?

every response is reinforced

What is intermittent reinforcement?

only some responses reinforced, usually according to a schedule of reinforcement

• Ratio schedules: based on the number of responses emitted

• Interval schedules: based on elapsed time 

• Fixed interval schedules (FI): reinforced after fixed amt of time has passed since last reinforcer

• Variable interval schedule: reinforced after variable amt of time has passed since last reinforcer (on avg)

• Fixed time schedule: same as FI but no response required

What’s an example of fixed interval schedules?

FI 15s means a response will be reinforced when 15 secs has elapsed since the last reinforcer

What’s an example of variable interval schedules?

 VI 30 secs means a response will be reinforced 30 s on average since the last reinforcer

What’s an example of fixed time schedules?

Skinner (1948) - 15 secs FT with pigeons

• Found idiosyncratic responding 

• Adventitious reinforcement of the behaviour occurring just before non-contingent reinforcer

Describe Differential Reinforcement of Other Behaviour (DRO)

1. Reinforcer delivered when fixed amount of time has elapsed since last response 

2. Explicitly reinforces non-responding (omission training)

3. Unwanted behaviour → negative punishment 

4. Other behaviour → positive reinforcement 

Eliminates behaviour more effectively than extinction

Describe Respondent conditioning

Respondent conditioning: learning association between 2 stimuli 

• Unconditioned stimulus that automatically elicits unconditioned response

• Previously neutral stimulus reliably predicts the unconditioned stimulus

• Hence, it becomes a conditioned stimulus that elicits the same response 

Give an example of respondent conditioning

bullet point 4: UR is meant to be CR

Define “The Matching Law”

the % of responses on one alternative equals the % of reinforcers from that alternative

• If a pigeon is trained to peck a yellow key for food reinforcement (VI schedule)

  • Its behaviour should change when we change key colour

Define “evolutionary psychology”

Scientific study of animal cognition & behaviour from evolutionary POV

• Precisely controlled experiments used to learn abt how animals think & how it compares to how humans think 

• Experiments used to rule out alt accounts of animal cognition (e.g. the animal was trained)

Romantics vs Killjoys

Romantics: believe animals have capacity for theory of mind & using tools/language, having empathy etc

Killjoys: insist that animal behaviour can be explained using associative learning 

Define “homology”

features shared between species due to shared descent 

• E.g. various species have 5 digits at the ends of their limbs (e.g. bats have 5 digits in their wings)

Define “analogy”

Analogy: concept of convergent evolution - not inheritance from starting point but converges at same endpoint

• Torpedo body shape in sharks → dolphins (developed this shape later) → reptiles → penguins (birds)

• Convergence occurs due to natural selection for different lineages to accommodate same function in shared environment

Necessary conditions for evolution by natural selection

1. Variation: different individuals in population has different morphologies, physiologies, behaviours

2. Heritability: variations must be heritable from parents to offspring

3. Differential fitness: if resources are limited, different phenotypes will have different survival & reproduction rates bc of differences in their design

Why study animal minds?

1. Shared ancestry: what we’ve inherited can be studied by identifying homologies with close relatives 

2. Cognitive adaptations to environment: how natural selection has shaped our minds 

Can be studied by looking for analogies in species living in similar environments

Animal minds can help us understand what makes us human & what features of our minds have been inherited by primates

Human uniqueness: tool use

Human ability to use tools believed to be unique to the species

• Until Jane Goodall (primatologist) observed David Greybeard (chimpanzee) use a stick to pull termites out of a hole

• Hence realisation that using tools wasn’t unique to humans (likely homologous w. chimpanzees)

  • Likely that features underlying ability to use tools in human physiology & cognition are also present in chimpanzees

Human uniqueness: language

Kanzi showed symbolic representation - could use pictures to refer to abstract things

• Reasonable evidence that Kanzi could understand word order (e.g. difference btwn pouring water first/cola first in a sentence)

• Some novel & spontaneous language use (e.g. ‘quiet’ & ‘water + bird’ when first seeing a swan)

Define “genotype”

what’s inherited

• Set of DNA molecules contained in nucleus

• Genotype particular to a trait

Define “phenotype”

 what’s developed

• Organism’s physiology, anatomy, behaviour

Describe chromosomes

thread-like structures contained in the cell nucleus

• Occurs in pairs

• Human somatic cells usually contain 23 pairs

Define “gene”

a stretch of DNA that produces a specific protein

Define “locus”

position of a gene on a chromosome (each has 2 alleles)

Define “allele”

alternative forms of a gene at the same locus

Define “homozygous”

 when an organism possesses 2 identical alleles for a particular trait

Define “heterozygous”

when an organism possesses 2 different alleles for a particular trait

What is a dominant allele?

an allele that manifests its effects in both heterozygotes & homozygotes e.g. brown eyes

What is a recessive allele?

an allele that manifests its effects only in homozygotes e.g. blue eyes

Define “polygenic inheritance”

 a trait whose phenotypic expression is influenced by many genes e.g. most psychological traits

Describe the Dunedin study (genes/aggression)

followed the lives of 1037 babies born between 1 April 1972 and 31 March 1973 at Queen Mary Maternity Hospital (carriers of MAOA gene)

Gene responsible for behaviour: Monoamine Oxidase (MAOA)

• Metabolises neurotransmitters 

• E.g. norepinephrine, serotonin, dopamine

Describe the findings of the Dunedin study

• Between ages 3-11, 8% of the children experience severe maltreatment 

• 28% experienced probable maltreatment

• 64% experienced no maltreatment

Researchers examined the effects of maltreatment & MAOA activity over time

Children who experienced severe maltreatment were more likely to…

exhibit antisocial behaviours

• Depicts how environment plays significant role in gene expression 

• MAOA gene has little to no effect on children who experienced no maltreatment

  • This gene is only associated with antisocial behaviour with children who experienced probable → severe maltreatment

What is the conclusion of the Dunedin study?

MAOA gene is not wholly responsible for violent behaviour, its effect depends on the environment 

Define '“heritability”

The proportion of variation in a population that is attributable to genetic differences

Describe one methodological issue with twin studies

Shields (1962) - IQ heritability 

40 pairs of separated identical twins 

• Found that the genetic variation in IQ compared to overall variation was 0.77

HOWEVER

Leon Kamin discovered that 27/40 were raised by close relatives 

• Environments were likely similar (separation/placement isn’t random) 

  • Heritability estimate for the 27/40 is 0.83 

  • Heritability estimate for the remaining 13 pairs is 0.51

Describe the dictator game

 situational experiment where one player gets a ‘windfall endowment’ (e.g. $20) & is asked how much of it they’d willingly share with another player

Describe the Muller-Lyer illusion

shows that our brains interpret visual angles as depth cues. The PSE measures how strong this bias is

• Western/Urban children had very high PSEs. They were strongly fooled by the illusion

• Non-Western/Rural children had much lower PSEs. They were barely fooled at all

Describe cross-cultural data of the Muller-Lyer illusion + why

people from non-urban environments have lower PSEs, proving basic visual perception is not purely biological - it’s culturally constructed based on the physical environment we grow up in

Heinrich: Most psychology research is done on WEIRD populations (Western, Educated, Industrialized, Rich, Democratic)

• Muller-Lyer illusion proves that if you only test American university students, you might conclude that this visual illusion is universal human trait

Describe over-imitation

children replicate actions that appear unnecessary, observed in settings where they are instructed through demonstrations 

• Condition 1: children & chimpanzees shown a demonstration on solving a puzzle box

  • Both replicate the function & nonfunctional steps to solve it
    

• Condition 2: the box is transparent, ppts can see all the mechanisms inside 

  • Chimpanzees did not imitate nonfunctional steps

  • Children still imitate nonfunctional steps 

Define “conformity bias”

copying the majority

Define “prestige bias”

copying the successful