Episodic-like Memory and other Behavior in Scrub Jays

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Episodic-like Memory and other Behavior in Scrub
Jays
Lecture 7 Psych 1090
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Ive done things a bit differently in this
lecture
assigning only a review paper for the earlier
material
and giving the details in the lecture
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What is episodic memory?

• unique, personal, past experience

• recalled in terms of a time frame or
  temporal-spatial relation

• thus tells what, when, and where

• not expected in nonhumans

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Explanation in terms of other forms of human
memory

• Procedural memory

• inaccessible to conscious recall

• examples are some motor skills, or simple
  classical (Pavlovian) conditioning

• Declarative memory

• involves propositional material, symbols

• used to guide inference, reasoning, true/false
  statements

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Declarative memory is subdivided

• semantic memory

• factual knowledge of the world

• what one knows from books, etc.

• episodic memory

• factual knowledge of past experience

• what one knows from living ones own life

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According to Tulving and Marlowitsch, episodic
memory is

• unique to each episode

• allows recall of past experiences rather than
  facts

• develops later in children is impaired faster
  in age than semantic memory

• related to unique cortical activity

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Supposedly, animals remember facts (semantic
memory) but not personal experiences (episodic
memory)
plenty of evidence to show that animals remember
that x indicates y, or if x, do y,
but not necessarily when I saw x, I then
remember doing y
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The point may seem trivial, but its not..
The difference is in knowledge that is assumed to
represent the way the world works for everyone
(semantic memory)
And knowledge that is understood to represent
only what one has personally experienced
(episodic memory)
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Which brings up another issue
Some researchers argue that to understand that an
experience is personal, a being must have full
consciousness.
an attribute that is generally denied to animals.
10
To get around the argument that a being must be
conscious in order to have personal
memoriesi.e., to have episodic memorywe can
simply agree
to define episodic-like memory as retrieval of
what, where AND when
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Thus the issue of personalization and of
self-projecting past to future
And of assuming that others experience life
similarly
Such a definition puts emphasis on the episode
aspect of episodic memory, and is one that can be
tested in animals
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Note that other types of memory that have been
studied may seem to involve time, but are not
truly episodic.
For example, animals trained on delayed
match-to-sample or delayed nonmatch-to-sample
may seem to be recalling previous, personal
events.
13
That is, being shown a red sample at time T and
then, at T20 seconds, being shown red and green
samples,
they have learnedvia trial and errorthat they
get rewarded
only for matching or not matching the original
sample shown at time T
14
One could argue that the animals are responding
based on personal, event-based memories..
They may, however, simply be choosing or avoiding
the most familiar object.
Which really has nothing to do with episodes
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Specifically.
There is a distinct difference between

• recognizing something as familiar

and

• a specific recollection of where and when it has
  been seen before

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Another example.
The difference between knowing a face is familiar
and
remembering that you saw this person last
Saturday night at the bar in Harvard Square
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But many animals likely demonstrate some kind of
episodic memory in nature.
Nest parasites, like cuckoos, must keep track of
the location and state of nest-building and egg
laying in their hosts
so as to know when to drop their eggs
18
And because recently researchers found that
cuckoos will destroy the nests of hosts who dump
their eggs
Some connections might be made in terms of
personal experience for both hosts and cuckoos
19
But probably the best example are food-caching
birds
As we learned last lecture
They store thousands of food items in the autumn
in thousands of locations, and recover them over
the course of several winter months
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And even though the scrub jays that are used by
Clayton et al.
dont cache nearly as much as the nutcrackers and
pinyon jays
they do cache some food, and for times a bit
longer than chickadees
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To connect to episodic memory

• information guiding recovery is based on a
  single, past, personal memory

• retrieval requires precise spatial data

• birds need to remember the order of caching to
  prevent spoilage

• birds need to remember precisely what was stored
  in which cache to prevent spoilage

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To get clear data on such behavior, Clayton and
Dickinson performed a series of experiments with
scrub jays
Birds were allowed to cache wax-worms (perishable
and preferred) and peanuts (non-perishable and
liked) in visually distinct sites in the
laboratory
Sites were ice cube trays with Lego blocks in
varied patterns
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(No Transcript)
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Birds were divided into two groups, Degrade and
Replenish
Birds in the Degrade group were given the
chance to cache peanuts and wax worms in two
different trays
and then recover at both 4 hours and 124 hours,
and to learn that the worms would be horrid after
124 hours
25
They then were tested by being allowed to cache
and recover the two different foods at the two
intervals
But now the experimenters removed all the food
items before recovery,
so birds couldnt possible smell the degraded
worms.
26
The researchers found that after 4 hours, the
birds preferred to visit the sites where they had
cached the worms
but went to the peanut sites after 124 hours
suggesting that they knew precisely what was
where and the time delay
27
But maybe the birds just remembered which caches
they had already emptied
Or maybe they just more rapidly forgot worm sites
i.e., maybe some evolutionary rather than memory
process was at work
28
So the researchers worked with the Replenish group
who never learned that the worms degraded
because the researchers put in fresh ones before
allowing recovery at 124 hours
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When tested with all food removed, these birds
preferentially went to the worm sites, at both 4
and 124 hours
Thus the behavior of prioritizing which food to
recover was learned, and not some genetic
instinct
And was nice preliminary evidence of
episodic-like memory
30
But this design still didnt examine whether the
birds in Degrade
understood more than time makes worms decay
i.e., just that something about the time at
which they stored the various foods was important
31
So now the birds could store both foods (nuts and
worms) in one tray at one time
then a few days later could again store both
foods in another tray
and after a short interval after the last
caching, were allowed to recover
32
So, in order to get worms and nuts appropriately
(avoid yucky worms)
they had to remember which tray was cached when
And not just better memory for nicer food
And they succeeded on that task
33
To tease this out even further, the researchers
designed another experiment
in which the birds got to store the different
foods at different times,
and then recover them at the same later time
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• Birds were thus allowed to cache one type of
  food in one side of the tray at first

• were made to wait 120 hours

• and then were allowed to cache the other type of
  food in the other side of the tray.

• the type of food altered with respect to time in
  two different sets of trials

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Test predict worms
Peanut, then Worm
P
P
W
W
120 h
4 h
Worm, then Peanut
Test predict nuts
P
P
W
dW
120 h
4 h
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Birds with experience with degraded worms
chose worms at a significantly higher rate than
peanuts when the worms were cached last
and peanuts at over twice the rate when the worms
were cached early and likely degraded
37
Interestingly.and critically.birds with no
experience with degraded worms chose the worms in
both cases
that is, they just chose on preference
not as to what was likely to have happened to the
worms
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Thus

• The peanut-side preference shown by the Degrade
  group was not simply due to differential
  forgetting of worm caches

• the preference to search for worms 4 hrs after
  caching and peanuts 120 hrs after caching does
  not reflect a genetic predisposition, because it
  was learned

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But what if the birds were trained on something
totally counter-intuitive.
That worms were yuckky after a couple of hours
But somehow were ok after a few days?
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Test predict nuts
Peanut, then Worm
dW
dW
P
P
120 h
4 h
Worm, then Peanut
Test predict worm
P
P
W
W
120 h
4 h
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And the birds acted as predicted
functioning on the basis of what they had learned
about worms
And it wasnt what they learned during the test
phase
because they acted OK from trial 1
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Moreover, the birds behavior was not just a
matter of familiarity of the tray
that is, somehow associating tray with the issues
because the tray exposure was the same for each
type of caching
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The switch by the birds in the Degrade group
requires the birds to recognize a particular
cache site
in terms of both its content and the relative
time that has elapsed between caching and recovery
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The birds HAD to recall information about

• what (worms vs. peanuts) was cached

• where it was cached (right vs. left)

• when (4 hrs vs. 120 hrs)

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Toothe information was acquired on the basis of
a single, trial-unique personal experience
That is.something getting quite close to
episodic memory
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Note the result cannot be explained by the simple
rule
search the side of the tray in which food was
stored most recently, regardless of food type.
birds couldnt use recency, because each food was
cached at the same time in different trials
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Researchers next wanted to make sure that the
birds remembered
not only which sites have been depleted (data
from experiments by Kamil and Balda that we
discussed)
but also exactly WHAT was recovered
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not just the choice of spoiled vs. unspoiled,
but also what might be more appealing at a
particular time.
which relies on a very personal memory for what
has been consumed recently
not just always go for X if its fresh
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So, they tested whether what they fed the birds
just prior to recovery would affect what they
recovered.
and also made them remember where the different
foods were stored in two different trays.
The trials are quite complicated!
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(1) cache P in one side of each tray
(3) 3 hrs later, allowed to recover P from one
tray and K from the other
A
P
A
/
P
K
B
P
P
K
/
B
A few mn
(2) cache K in one side of each tray
(4) Prefeed bird P, see what it does
A
K
P
K
/
P
A
B
K
P
B
/
K
P
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Assumption is that bird that is full of peanuts
will choose the kibble, and remember where the
kibble still was
even after additional time delay
52
Of course, during test, all food was removed by
the experimenter to prevent any odor or
disturbance cues
So birds should not rely on a scent or preference
for food
but on satiation
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Note that birds have to INTEGRATE information as
to

• what it cached where

• what it recovered where

• what was same/different from what it had just
  eaten

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9 of 12 birds upheld the prediction of feeding
from the tray
that held food different from what it had just
eaten
Birds made twice as many searches to the place
where there was intact different food
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as to where there was intact same food
birds made very few searches to depleted sites
And this did not depend on training about good
or bad types of food
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Three main conclusions from these data

• Birds encode info about what they store in a site

• Birds can update their memory as to whether they
  have depleted one of two sites, even if they
  essentially bated them simultaneously

• Birds can integrate these two bits of information

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Now, those of you who have been mulling about the
peanut/mealworm study may have realized a
possible flaw in the experimental design
Maybe the birds just have a differential memory
for remembering stuff that spoils versus stuff
that does not.
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rather than remember when stuff was cached
In other words.
Birds that experienced degradation not only
learned something about what is good to eat when
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But also that, in general, its best to remember
where peanuts are stored because they are a more
reliable source of food
So dont clog memory with information about
degradable mealworms.
Thus researchers had to figure out a way around
that problem..
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They did so by replicating the experiments with
crickets instead of worms
Crickets degrade more slowly than worms,
so the researchers could see if birds
progressively recovered crickets more slowly as
the days went by
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Thus, if birds were just not bothering to
remember where a degradable food was cached
and they didnt like the degradable crickets as
much as the degradable worms
but they liked the crickets only as much as the
peanuts
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they should start skipping the crickets
immediately
If, instead, they remembered crickets as well as
peanuts,
and when they cached
they should go for the cricket for the first day
or so after caching and stop after about 3 days
63
Interestingly, almost none of the 6 birds
involved went for peanuts on the first three days
By day 5, all 6 birds went to peanuts first..
The birds seemed to make a categorical decision
as to change their behavior around day 4
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Thus, it could still be that the birds were not
directing a lot of resources to remembering
crickets
or had some kind of intermediate range memory
in which they stored information about degradable
food
compared to long-range memory for nondegradable
items.
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So, the idea was to give the Degrade birds
staggered caching and then see what the birds did
on progressive days.
Cache day 1
Cache day 3
Cache day 2
P
C
P
C
P
C
1
2
3
Recover day 6
Recover day 5
Recover day 4
P
P
dC
dC
?
?
3
1
2
This time, tho, some birds were given degraded
crickets on Day 3
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Before, remember, crickets were still pretty good
on Day 3
If they really remembered what they cached and
when
they would go for peanuts on day 6 in the last
tray that was cached
only if they experienced degraded crickets on day
3
67
But if they were the group that had not had rummy
crickets on Day 3 for the first two trays,
they should still go for crickets on day 3
because crickets were usually good until day 4
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And, to make sure that the birds just now didnt
decide that any cached crickets were worthless,
they were given good crickets on a Day 1 recovery
trial
The idea was to see if the researchers could
tweak the encoded information.
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Showing that the information was indeed encoded
and not just that crickets were relegated to a
specific memory bin
Most of the birds that got degraded crickets on
Day 3 for trays 1 and 2 did search for peanuts on
Day 3 for tray 3.
70
In general, the birds had encoded some kind of
semantic memory about the state of crickets over
time (i.e., that they degrade in a few days)
And then integrated this information with respect
to where and when they had cached the crickets..
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And they were able to update their general
semantic knowledge of the world based on new
information.
These data fit with the ethology of the scrub
jays, who cache items under varying conditions.
and thus must determine the effects of, e.g., a
hot spell on their caches
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So, these data suggest that birds fulfill the
criteria for episodic memory
What, When, Where
But is this behavior identical to that of humans,
as Suddendorf and Busby question?
We still do not know.
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We dont know if the birds are simply reacting on
the basis of semantic memory.
That is, on some version of this is just how the
world works
versus some understanding that the situations are
specific to themselves or allow them to project
ahead.
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Specifically, one can argue that the birds have
each remembered a setalbeit a very complex
setof facts and integrated these facts.
Thus demonstrating an extremely high level of
complex cognitive processing
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What is needed is to show that the animal
remembers a specific episode
that is, where I was and what I was doing on
September 11, 2001.
And not just a collection of facts that allow me
to solve a problem
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because what you were doing was dissociated from
the events
Is there any way to get around that problem?
Possibly, by designing experiments in which a
bird has to separate out its own experiences from
that of other birds..
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This strategy isnt perfect
because it still cant separate out the bird as a
dispassionate observer from what is going on
around it
But it is a start in the right direction
78
Researchers realized that scrub jays will steal
from one anothers caches..
And that as a precaution, some jays will re-cache
items
if their initial caching is observed by other
jays.
79
So maybe researchers could work with that
knowledge to see if they could personalize the
birds memories
And also see if the birds could project their
knowledge to the future
80
So, one group of birds watched another group
cache, and then was allowed to pilfer.
Another group of birds never had this experience
of being allowed to pilfer.
although they could watch caching
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Both sets of birds were then allowed to cache in
the presence of a competitor.
Both sets of birds were then given the
opportunity to re-cache their hoards in private.
Pretty much only those that had pilfered other
birds stores did re-cache
82
These data begin to suggest that birds do have
memories that, if not specific to themselves,
at least suggest some sense of attribution to
others.
Specifically.if I pilfered another birds hoard
whom I watched, someone watching me may pilfer
mine
83
Of course, one can always come up with
alternative explanations.
Something a bit less mentalistic.any ideas???
Wellit seems that birds are acting as tho if
they do something, all other birds will do the
same thing.
that is, generalization
84
Such behavior does not really impute
intentionality or personal experience.
What one would really have to show is that birds
recognize specific individuals
and that these individuals are indeed pilferers
85
and react only in the presence of a bird that
they have reason to expect will pilfer their
food.
not simply react on a generalized basis
Testing this with respect to actual knowledge is
difficult
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But possibly testing it with respect to the birds
having some idea
of what a potential pilferer may or may not be
able to see might work
Some evidence exists for ravens
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If other ravens are around
the storer will wait until those birds are
distracted or have moved away
or will make false caches and false recaches
or store behind barriers
88
But, again, are the birds acting as if they
really have a Sally-Ann sense of theory of mind
or are they also working on a sort of
generalization of this is what should be done in
this circumstance
without fully knowing why?
89
One can set up an experiment in which the storer
sees who is stealing some of its cache
And determine if the storer will then respond in
a way that suggests it knows something about this
specific competitor
compared to how it treats food stored in private
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So, storers had three trials where they could
store in private
And three trials where they knew that one
potential pilferer was watching
In each case, two trays were available, at
different ends of their cage
91
The same potential pilferer saw all three trials
Interestingly, storers also sometimes cached
outside of the trays, but experimenters removed
those caches
Experimenters also noted how much was eaten
92
Then, in the presence of the storer, the pilferer
was given one tray
while the other tray was out of reach of both
birds (trays marked w/ Legos)
And pilferers could eat a cache or re-cache it in
same or different site
93
In contrast, after the storer had stored in
private
the trays were observed by both birds, but no one
could reach either tray
thus observation time for all four trays was equal
94
Then the storer, now in private, got back two
trays

• two trays had been cached in private and seen by
  both birds

• two trays had been cached in public, both seen
  by both birds, but only one accessible to the
  pilferer

What did storer do?
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For whatever reason, birds cached a bit more when
being observed
Pilferers got about 50 of what had been stored
when they could access a tray
But overall, about the same number of items were
left for recovery remember, 3 unpilfered trays
96
The original storers didnt differ in how much
they ate or checked their caches when they got
the trays back in the two conditions
But they did re-cache more items in the trays
that the pilferers had observed than in trays
stored in private
97
They discriminated the particular trays that the
pilferer had observed
And, interestingly, they took food out of the
observed trays more often
Stuffing it in sites in the cage that could not
be accessed by the pilferer at all
98
They also ate a lot more after being in trials in
which the observer ate some of their caches
Here they werent just observed, but actively saw
their caches being pilfered,
which is a fairly strong condition
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In a separate study on other cachers, the Grey jay
This species would cache in front of a nutcracker
because nutcrackers dont pilfer
but wouldnt cache in front of Stellar jays that
do
100
None of these observational studies, however,
deal with social effects
In the wild, many of these birds have social
hierarchies that affect who has access to food
And may affect caching if good sites are limited
101
In a 2005 paper (Dally, Clayton, and Emery,
Behaviour) looked at caching in an aviary in
which there existed a social hierarchy
They found that the alpha pair would cache more
than the beta pair
And that the alpha pair knew where each other
cached and didnt care who recovered the cache
102
But the alpha pair seemed to defend their caches
from the other birds
And when the alphas were removed, the betas then
became the alphas
And took over the caching
103
Probably the subordinate birds knew they could
not defend cache sites from the domiants
And basically just gave up on it
The effect might, however, have to do with being
in an aviary
104
In the wild, the subordinate might need to cache
more.
Here, the birds were basically well-fed and
limited only slightly
Might be a totally different story in the wild w/
limited food available and the need to steal and
cache
105
In yet another 2005 study (Animal Behaviour,
Dally, Emery and Clayton) looked at positional
factors in social settings
Here birds had a choice of where to store under
conditions of being watched or not
sites were either close or far
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(No Transcript)
107
If the bird had a general theory of just storing
as far away from any possible observer
it would always use the far tray
Even if, in this case, the bird saw a screen
being pulled down between it and a neighbor
108
If, however, it was sensitive to the condition of
not being viewed
It should cache randomly in the two possible trays
The expt would show whether the bird was really
aware of what the other bird could see
109
Now, this time the birds did not see anyone eat
their food before the trays were removed
And they had successive trials so that they could
learn what was happening to their hoardes
Which could all affect results
110
Again, for whatever reason (maybe fear of
pilfering?) more food was cached when the birds
were observed
And more food was put in the far tray when the
birds were observed
suggesting that being observed had an effect
111
More food from the near trays were re-cached
during recovery
Note that in the three hours in between caching
and recovery, the screen was installed
So the storers had no idea what had happened to
their trays
112
This condition is quite different from the one in
which the storers saw the pilferers go to work
But the fact that the storers re-cached in
private suggests that they knew that by caching
all the stuff initially in the far space wouldnt
be good either
113
Although this might suggest a sort of awareness,
it may not
Could just be a simple idea of trying to avoid
being near a conspecific during caching
And moving stuff away from the site it was at
114
What if you put non-cacheable food near the
observer?
Would the bird go near the observer?
What if you played with the details of where the
observer could be?
115
Birds happily ate in view of the observer
So they werent simply avoiding another bird
And their behavior during caching wasnt just due
to avoiding the other bird
116
In terms of playing with the spacing, the
experimenters set up the cages so that the birds
could see one another in a limited way
and sometimes the observer was stuck on one side
or the other
but the storer could move
117
Up close, pilferer can see only one site
118
No matter which side the potential pilferer was on
The storer cached in the far and unseen location
Interestingly, the caches were moved more often
when the potential pilferer could move about
119
And sometimes the birds would cache in view and
then recache several times
As if the confuse the pilferer as to where the
item was.
Of course, the cacher could just be dithering here
120
Another problem is that the unseen site is always
the further one away.
So we still dont know if the bird is acting upon
what it thinks is the sight of the potential
pilferer
Or it just wants to store in a far location.
121
Hence, another setup
Seen and unseen are now equi-distant
122
Here jays could also cache totally in private
But, for whatever reason, they did not!
But when they were viewed, they put more in the
out-of-sight tray than the one in-sight
123
But, this still could be some kind of out of
sight, out of mind behavior.
What is needed is a system in which the pilferer
can be seen by the storer
But the storer knows it is unseen
124
In yet another study, jays seemed to understand
which bird was the observer and react
appropriately
So, for example, it didnt care if its partner
saw a cache (all in the family)
But did react if a dominant saw it cache
125
And the experimenters had problems because some
birds stopped caching at all in the presence of
observers
And birds would respond differently when birds
that observed recovery were not birds that
observed caching
So the birds seemed to attribute some knowledge
to the observer
126
Or at least some memory of the observer and some
memory of what might have happened in a related
situation.
We are getting closer and closer to some kind of
TOM
But its always difficult to know for sure
127
In terms of planning, however, a recent paper
(Nature, 2007, 445 919-921) does show clever
behavior on the part of the jays.
First experiment involved planning for
breakfast to see if birds would provision
themselves depending upon their knowledge of the
future
128
Powdered nuts
No food
Later in day, learned that they could eat in B,
too, but just powdered nuts
129
Then they were given whole nuts in B in the
evening.
They put more nuts in C than A
Ostensibly to compensate for lack thereof
130
But to make sure the birds werent simply
associating caching and hunger
The experiment was repeated with nuts in A and
kibble in C
And then they were given both nuts and kibble in B
And they put kibble in A and nuts in C
Showing some level of planning
131
Overall, the data demonstrate incredible
abilities that were not thought to exist in any
nonprimate other than humans and apes, much less
in a bird!
132
Which, of course, brings up the monkey
paper..what about other nonprimates?
Now, of course, rhesus monkeys do not normally
cache
It does not make ecological sense
133
Most of their food is perishable
And most of the time it is not limited in any
real way
So that the idea of worrying about caches is not
likely
134
What may be true for monkeys, however,
is when a particular tree is fruiting
with respect to a particular location in the
forest
Maybe this is less precise, or is seasonalbut
could be episodic
135
So, although monkeys might not be the best
possible subjects
There might be some reason why they might have
something like episodic memory.
But will this task show it?
136
(No Transcript)
137
Monkeys had two different foods, one yummy and
one less so
They could then go back after either a long or a
short delay
Both foods were available after short delay only
less yummy food after a long delay
138
Would they learn, over training,
which food would be available after different
delays?
Note how this differs from the jays
in what is available
139
Learning that something just disappears over time
can be seen as just someone else eating it up if
you dont get to it first
which is a subtle difference from something that
has to do with time per se
140
And this task used some monkeys with hippocampal
lesions
Now we know that the hippocampus involves spatial
memory
But some areas of the hippocampus also seem to be
involved with episodic memory
141
or possibly, as we saw in the last lecture, the
connections between the hippocampus and other
parts of the brain
One idea is that the where and when of the
what-where-when may be closely tied together.
which might explain corvid success on both sets
of tasks
142
So, monkeys had three foraging sites, one empty
and two w/ foods of differing appeal
In training, the placement of the sites vary
between, but not within, sessions
So monkeys had to forget between sessions (time
not given) and remember within session placement
143
Although there is no report of within-session
timing, it sounds as tho it was just a few
minutes between runs.
Enough to pull monkeys to cage, cover w/ tarp,
and re-bait the sites
We are not told the time delay between sessions
144
But this time delay is crucial
Because it sets up what delay the monkeys expect
during which the expected sites have been altered!
The assumption is 24 hrs, given that food
preference tests were given on a 12 trial/day
basis
145
Monkeys were considered trained if they went to
preferred food on the last 3 of 4 runs in a
session.
They acquired what is known as a learning set
where they learn a task, and small variations on
the task are learned successively more rapidly
146
Then they were tested.
They went into the room, had, again, a unique set
of placements
had the chance to learn where the good food had
been hidden
Both the controls and lesioned animals quickly
learned to find treat
147
They also learned to avoid the less tasty food
So at least for these very short delays (a few
minutes) within sessions
lesions had no effect on how well the animals
remembered the two sites
148
Then they were tested after each of the study
trials
Now with first 1 hr and then 25 hr delays
149
After a 1 hr delay, the monkeys were allowed into
the site
Nothing had changed
Researchers noted which food was chosen first,
but monkeys had to visit both sites to end a trial
After choosing the good food, the marker was
removed to encourage choice of the second site
150
After 25 hrs, the monkeys went back into the
experimental room
Nothing had changed in the placement, UNLIKE the
previous training phase
Now, however, the good food was degraded to be
yuckky
151
Now remember, each test trial consisted of 8 runs
for the animals to learn where the foods were
Then one run an hour later and another run 25 hrs
later
Each monkey had 30 of these test trials not sure
of the time between test trials
152
The experimenters expected that, with time, the
monkeys would stop going to the preferred food
after the 25 hr delay.
Remember, the jays learned that worms got yuckky
after 4 days
But the monkey data didnt quite work out that
way.
153
First of all, the monkeys didnt bait the areas
themselves
Second, the sites changed initially from one day
to the next
So after a 25 hr break, they may have expected
the room to look different.
154
But now, sometimes, instead of seeing a different
setup
which they had learned meant some trial-and-error
choice
they saw a familiar pattern
How easy would it be to learn to ignore that????
155
We know that reversals are tough to acquire
And thats what the monkeys had to learn
So its likely there was a lot of interference
going on
156
The lesioned monkeys more often examined unbaited
sites
suggesting that they indeed had a poorer memory
for the location of any kind of foodgood or bad
Toward the end of the paper, the authors admit
that their training might have skewed the results
157
But they then discount the possibilityfor what
seem to be odd reasons
The point is that the continued shifting of the
sites for the animals during training blurs the
situation
What IS an episode for them?
158
Unlike the Clayton studies, the monkeys were
trained in a particular way, then tested with a
glitch
and then were expected to figure out a
correlation that was obvious to the researchers
but one that would not necessarily be obvious to
an individual experiencing the task
159
Too, although Clayton couldnt put every control
in every experiment
each experiment was a consistent whole, with no
claims as to having controlled for every variable
Although one could see the work as really on
large paper instead of several individual ones
160
These studies, of course, get into the realm of
questioning what it is that the animals actually
do know
and, of course, what they know that they
knowi.e., metacognition
The suggestion is that metacognition is necessary
for episodic memory
161
But do you need to know that you know that worms
degrade?
Metacognition might be more important in the
pilfering study
in terms of getting to a kind of theory of mind
behavior
But none of these cases are clear
162
An animal might know what food is hidden where
and whether it is still good
but not know HOW or WHY they know it
No reasoning would be involved, just some memory
returning when visiting the area
163
Humans use language to declare this information
How can we get at it in animals that have no, or
only very limited, interspecies communication
skills?
Some studies purportedly allow monkeys to state
if they do or do not remember the answer to a
task
164
But in reality the animals reporting of
uncertainty just allows them a third choice when
a first choice doesnt surface quickly
It may not be any more conscious than any other
type of choice they are given
165
Some researchersSuddendorfargue that episodic
memory is really a means of future planning
using the past to project to the future
How would that help us understand animals?
166
Clearly the jays store for the future and monkeys
do not
But that doesnt get to the idea of whether the
jays behavior is a mixture of instinct and
knowledge
or self-awareness of what is individually needed
167
Would seem that the jays actions in preparing
for the contingency of another animal pilfering
might actually tell us more than the caching
behavior itself
Wouldnt it be great to ask Jay A where he
thought Jay B would search after A re-cached?
168
The implication is that Jay A thinks Jay B will
look in the old site and be fooled
Otherwise why would Jay A re-cache?
But Jay A re-caches in sight of Jay B
169
Such would seem to be a silly behavior, and thus
researchers make an argument for confusion
But is Jay A really pondering such an outcome, or
just kinda freaking out and maybe trying to find
a slightly better hiding place?
or hoping B will lose interest?
170
The take-home message is basically the cleverness
of the birds and the need for truly complicated
experiments in order to uncover their cleverness