Comparative CognitionComparative Cognition

Psychology 3306Psychology 3306

IntroductionIntroduction

Comparative psychology is almost as old Comparative psychology is almost as old as the discipline itselfas the discipline itself

People have wondered what animal is People have wondered what animal is smarter than what other animal for yearssmarter than what other animal for years

Many studies have looked for things such Many studies have looked for things such as serial position effects, short term and as serial position effects, short term and long term memory etc in rats and pigeonslong term memory etc in rats and pigeons

There is an implicit question hereThere is an implicit question here

And that question is….And that question is….

‘‘Can rats do what humans do?’Can rats do what humans do?’On the surface this seems an interesting On the surface this seems an interesting

question and indeed almost sensiblequestion and indeed almost sensibleWhat is the basis for such a question?What is the basis for such a question?Well, we must be at the top of some sort of Well, we must be at the top of some sort of

evolutionary ladder (Campbell and Hodos, evolutionary ladder (Campbell and Hodos, 1969)1969)

WRONG thanks for playingWRONG thanks for playing

There is no top, there is no goalThere is no top, there is no goal

These ideas are, simply, wrong!These ideas are, simply, wrong! The much better question is ‘what has driven The much better question is ‘what has driven

some species to be able to solve a certain type some species to be able to solve a certain type of problem?’of problem?’

What selective pressures then, have lead to the What selective pressures then, have lead to the evolution of certain cognitive mechanismsevolution of certain cognitive mechanisms

Asking what species is the smartest is a silly Asking what species is the smartest is a silly questionquestion

http://www.exn.ca/Templates/printstory.asp?http://www.exn.ca/Templates/printstory.asp?PageName=Animals&story_id=2001050453PageName=Animals&story_id=2001050453

So, how do we do comparisonsSo, how do we do comparisons

Let’s say we compare two species on Let’s say we compare two species on some tasksome task

How do we know that any differences we How do we know that any differences we find in cognitive ability may not be due to find in cognitive ability may not be due to differences in motivation?differences in motivation?

Bitterman’s ideasBitterman’s ideas

MacPhailMacPhail

MacPhail basically says that in science we MacPhail basically says that in science we start out with the null hypothesis, that start out with the null hypothesis, that nothing happened, there is no effectnothing happened, there is no effect

In our case, there is no difference between In our case, there is no difference between two speciestwo species

But keep that motivational thing in mind, But keep that motivational thing in mind, any difference could be motivational any difference could be motivational

Al Kamil’s responseAl Kamil’s response

There is a bit of a flaw There is a bit of a flaw therethere

You set up an You set up an hypothesis that you hypothesis that you cannot reject!cannot reject!

So how do we fix it So how do we fix it Al?Al?

Test many species on Test many species on many paradigmsmany paradigms

OK, I am with you so far AlOK, I am with you so far Al

If we find similar differences in many If we find similar differences in many different tests, it is unlikely that motivation different tests, it is unlikely that motivation will always be the culpritwill always be the culprit

Error cancelsError cancelsLook at life history, biology, neuroscience Look at life history, biology, neuroscience

and psychologyand psychologyAsk what sort of differences should have Ask what sort of differences should have

evolvedevolvedMake PREDICTIONSMake PREDICTIONS

Most awesomest example ever of Most awesomest example ever of the synthetic approachthe synthetic approach

Anderson and Krebs, 1978Anderson and Krebs, 1978Mathematical model of when food storing Mathematical model of when food storing

should evolveshould evolveFood storing can only evolve if you Food storing can only evolve if you

recover your own cachesrecover your own cachesSherry, Avery and Stevens (1981)Sherry, Avery and Stevens (1981)Birds seem to recover own seeds using Birds seem to recover own seeds using

memorymemory

More dataMore data

Shettleworth and Krebs, 1982Shettleworth and Krebs, 1982Marsh tits storing seeds in a labMarsh tits storing seeds in a labBetter at recovery of cached seeds than Better at recovery of cached seeds than

randomly placed seedsrandomly placed seedsHalf of seeds removedHalf of seeds removedThey are using memoryThey are using memory In other general memory tests, there have In other general memory tests, there have

been clear differences between storers been clear differences between storers and non storers in the corvid familyand non storers in the corvid family

We have already discussed the We have already discussed the hippocampal differenceshippocampal differences

But what about the parids?But what about the parids?Data are equivocalData are equivocalMaybe it is not how much they remember, Maybe it is not how much they remember,

but how they rememberbut how they remember

Qualitative vs. Quantitative Qualitative vs. Quantitative differencesdifferences

Brodbeck and his Brodbeck and his colleagues…. (ahem) colleagues…. (ahem) pioneered this type of pioneered this type of workwork

Comparing storers Comparing storers and non storers on and non storers on what they remember what they remember in different tastsin different tasts

Brodbeck, 1994; Brodbeck, 1994; Brodbeck and Brodbeck and Shettleworth, 1995Shettleworth, 1995

Brodbeck, 1994Brodbeck, 1994

Chickadees would find a Chickadees would find a seed in a feederseed in a feeder

Usually return later and Usually return later and eat iteat it

Move them around to Move them around to dissociate colour and dissociate colour and spatial locationspatial location

The chickadees The chickadees responded last to the responded last to the correctly coloured feedercorrectly coloured feeder

Non storing Dark Eyed Non storing Dark Eyed Juncos responded to all Juncos responded to all three cue types equallythree cue types equally

And the comparisons continueAnd the comparisons continue

Same thing on a smaller scale using a computer Same thing on a smaller scale using a computer touch sensitive monitortouch sensitive monitor

Birds rewarded for going to one place and not Birds rewarded for going to one place and not anotheranother

Different coloured patchesDifferent coloured patches Switch them aroundSwitch them around Chickadees rely on space, juncos do notChickadees rely on space, juncos do not Indeed, in another experiment it was determined Indeed, in another experiment it was determined

that chickadees when directly tested to very that chickadees when directly tested to very poorly on coulor!poorly on coulor!

FunctionallyFunctionally

Well functionally this makes a lot of senseWell functionally this makes a lot of sense Birds remember WHERE something is, not what Birds remember WHERE something is, not what

colour it iscolour it is Colours changeColours change That line of trees over there is still going to be That line of trees over there is still going to be

over thereover there However, the strange result really is that of the However, the strange result really is that of the

junco!junco! Brodbeck, Boisvert, Vaughan and Grant (1997)Brodbeck, Boisvert, Vaughan and Grant (1997)

Memory for Space/Colour Memory for Space/Colour Compound Stimuli in Pine Compound Stimuli in Pine

SiskinsSiskinsDavid R. BrodbeckDavid R. Brodbeck11 and Jessica M. Humber and Jessica M. Humber22

11- Psychology Department- Psychology Department22- Environmental Science Unit- Environmental Science Unit

Sir Wilfred Grenfell CollegeSir Wilfred Grenfell CollegeMemorial University of NewfoundlandMemorial University of Newfoundland

IntroductionIntroduction Pine Siskins are finches Pine Siskins are finches

that breed in Northern that breed in Northern North America and North America and conduct the odd invasion conduct the odd invasion into Central and Southern into Central and Southern parts of the US and even parts of the US and even in to Mexicoin to Mexico

Their abundance on the Their abundance on the West Coast of West Coast of Newfoundland made Newfoundland made them an ideal subject for them an ideal subject for field studyfield study

IntroductionIntroduction

We decided to test, first of all, if they could We decided to test, first of all, if they could be trained to go to different feeders that be trained to go to different feeders that had different amounts of foodhad different amounts of food

Feeders were placed a few metres apart Feeders were placed a few metres apart with sunflower seeds in a 3:2:1 ratiowith sunflower seeds in a 3:2:1 ratio

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Seems they can…Seems they can…

The birds distributed their feeder visits The birds distributed their feeder visits roughly in a 3:2:1 ratioroughly in a 3:2:1 ratio

This of course could be due to the birds This of course could be due to the birds actually seeing how much seed was in actually seeing how much seed was in each feedereach feeder

Or they could have emptied the rightmost Or they could have emptied the rightmost feeder first, the centre one second and the feeder first, the centre one second and the leftmost feeder last…..leftmost feeder last…..

Well there’s an empirical question if Well there’s an empirical question if I ever heard one…I ever heard one…

Well we covered up Well we covered up the feeders and the feeders and started swapping one started swapping one feeder with another feeder with another during test during test observation sessionsobservation sessions

So, instead of say So, instead of say ‘green’ ‘red’ ‘yellow’ ‘green’ ‘red’ ‘yellow’ we would now have, we would now have, on one test ‘red’ on one test ‘red’ ‘green’ ‘yellow’‘green’ ‘yellow’

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So what does it all meanSo what does it all mean

Good question…Good question…Seems the siskins respond based on Seems the siskins respond based on

space, sort ofspace, sort ofThey respond based on space if the most They respond based on space if the most

profitable feeder is not in the exact profitable feeder is not in the exact opposite position it should be inopposite position it should be in

Once this happens they seem to treat the Once this happens they seem to treat the array as if it is a brand new array they array as if it is a brand new array they know nothing aboutknow nothing about

Thanks toThanks to

Animal MemoryAnimal Memory

Working MemoryWorking MemoryMemory needed to solve one trial of a tastMemory needed to solve one trial of a tast

Reference MemoryReference MemoryThe rules of the gameThe rules of the game

Some cool preparations for Some cool preparations for studying animal cognitionstudying animal cognition

Delayed matching to SampleDelayed matching to SampleDelayed Non Matching to SampleDelayed Non Matching to Sample

Can be qualitative differences hereCan be qualitative differences here (Mackintosh, Wilson and Boakes, 1982)(Mackintosh, Wilson and Boakes, 1982)

Both subject to proactive and retroactive Both subject to proactive and retroactive interferenceinterference

Symbolic matching and prospective and Symbolic matching and prospective and retrospective encodingretrospective encoding

Roitblat 1980Roitblat 1980

Symbolic matchingSymbolic matching1) Red sample -> Horizontal line1) Red sample -> Horizontal line2) Orange Sample -> Vertical line2) Orange Sample -> Vertical line3) Blue Sample -> Almost vertical line3) Blue Sample -> Almost vertical line If they make mistakes when the choices If they make mistakes when the choices

are 1 and 2, they are encoding are 1 and 2, they are encoding retrospectivelyretrospectively

If they do when the choices are 2 and 3, If they do when the choices are 2 and 3, they are encoding prospectivelythey are encoding prospectively

More cool paradigmsMore cool paradigms

8 Arm radial maze (Olton and Samuelson, 1976)8 Arm radial maze (Olton and Samuelson, 1976) We talked about Suzuki et al early onWe talked about Suzuki et al early on Macuda and Roberts (1997) found that rats Macuda and Roberts (1997) found that rats

actually chunk!actually chunk! Directed forgetting experiments!Directed forgetting experiments! Inman and Shettleworth (1999)Inman and Shettleworth (1999) Brodbeck (1997), Brodbeck and Caines (2005) Brodbeck (1997), Brodbeck and Caines (2005)

pigeons show priming just like humanspigeons show priming just like humans