Episodic-like Memory and other Behavior in

Scrub Jays

Episodic-like Memory and other Behavior in

Scrub Jays

Lecture 7

Psych 1090

I’ve done things a bit differently in this lecture…

assigning only a review paper for the earlier material

and giving the details in the lecture

What is episodic memory?What is episodic memory?

unique, personal, past unique, personal, past experienceexperience recalled in terms of a time recalled in terms of a time frame or temporal-spatial frame or temporal-spatial relationrelation thus tells ‘what’, ‘when’, and thus tells ‘what’, ‘when’, and ‘where’‘where’ not expected in not expected in nonhumansnonhumans

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

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 one’s own life

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

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’

The point may seem trivial, but it’s 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)

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.

To get around the argument that a being must be conscious

in order to have personal memories—i.e., to have

episodic memory—we can simply agree

to define episodic-likeepisodic-like memory as retrieval of

“what”, “where” AND “when”

Such a definition puts emphasis on the ‘episode’ aspect of episodic memory, and is one that can be

tested in animals

Thus the issue of personalization and of self-projecting past to

future

And of assuming that others experience life similarly

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….

That is, being shown a red sample at time T and then, at T+20 seconds,

being shown red and green samples,

they have learned—via trial and error—that they get rewarded

only for matching or not matching the original sample

shown at time T

They may, however, simply be choosing or avoiding the most

familiar object….

One could argue that the animals are responding based

on personal, event-based memories…..

Which really has nothing to do with ‘episodes’

Specifically….

There is a distinct difference between

recognizing something as ‘familiar’

and

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

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

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

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…

They store thousands of food items in the autumn in thousands

of locations, and recover them over the course of several winter

months

But probably the best example are food-caching birds…

As we learned last lecture

And even though the scrub jays that are used by Clayton

et al.

don’t cache nearly as much as the nutcrackers and pinyon jays

they do cache some food, and for times a bit longer than

chickadees

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

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…

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

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 couldn’t possible smell the degraded worms….

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

Or maybe they just more rapidly forgot worm sites…

But maybe the birds just remembered which caches they

had already emptied…

i.e., maybe some evolutionary rather than memory process was

at work…

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

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

But this design still didn’t examine whether the birds in

“Degrade”

…i.e., just that something about the time at which they stored the

various foods was important

understood more than “time makes worms decay”

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 trayand after a short interval after the last caching, were allowed

to recover

So, in order to get worms and nuts appropriately (avoid yucky

worms)

they had to remember which tray was cached when

And they succeeded on that task

And not just better memory for nicer food

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

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

Peanut, then Worm

Worm, then Peanut

P

P

P

W

W

WP

dW

120 h

120 h

4 h

4 h

Test: predict worms

Test: predict nuts

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

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

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

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?

Peanut, then Worm

Worm, then Peanut

P

P

P

dW

W

dWP

W

120 h

120 h

4 h

4 h

Test: predict nuts

Test: predict worm

And the birds acted as predicted

functioning on the basis of what they had learned about worms

And it wasn’t what they learned during the test phase

because they acted OK from trial 1

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

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

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)

Too…the information was acquired on the basis of a

single, trial-unique personal experience

That is….something getting quite close to episodic memory

Note the result cannot be explained by the simple rule

birds couldn’t use recency, because each food was cached at the same time in different trials

“search the side of the tray in which food was stored most recently, regardless of food

type”….

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

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 it’s fresh

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!

AA

B

B

A

(1) cache P in one side of each tray

P

KP

KP

P

(2) cache K in one side of each tray

(4) Prefeed bird P, see what it does

(3) 3 hrs later, allowed to recover P from one tray and K from the other

B

A

/P

P K

K

K

B /

/

/

A few mn

KP

P

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

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

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

9 of 12 birds upheld the prediction of feeding from the

tray

Birds made twice as many searches to the place where

there was intact different food

that held food different from what it had just eaten

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

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

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….

In other words….

Birds that experienced degradation not only learned

something about what is good to eat when

rather than remember when stuff was cached…

But also that, in general, it’s best to remember where

peanuts are stored because they are a more reliable source of

foodSo don’t ‘clog’ memory with

information about degradable mealworms….

Thus researchers had to figure out a way around that

problem…..

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

Thus, if birds were just not bothering to remember where a

degradable food was cached

and they didn’t like the degradable crickets as much

as the degradable worms

but they liked the crickets only as much as the peanuts

If, instead, they remembered crickets as well as peanuts,

and when they cached

they should start skipping the crickets immediately

they should go for the cricket for the first day or so after caching and stop after about 3 days…

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

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.

So, the idea was to give the Degrade birds staggered caching and then see what the birds did on progressive days….

Cache day 1

Recover day 6

Recover day 5

Recover day 4

Cache day 3

Cache day 2

1 2 3

31 2

P

PP

PPC CC

dCdC ? ?

This time, tho’, some birds were given degraded crickets on Day

3

If they really remembered what they cached and when

Before, remember, crickets were still pretty good on Day 3…

they would go for peanuts on day 6 in the last tray that was

cachedonly if they experienced degraded

crickets on day 3

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

And, to make sure that the birds just now didn’t 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….

Showing that the information was indeed encoded

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….

and not just that crickets were relegated to a specific memory

bin

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…..

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

So, these data suggest that birds fulfill the criteria for episodic

memory:

But is this behavior identical to that of humans, as Suddendorf

and Busby question?

We still do not know….

What, When, Where

We don’t 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….

Specifically, one can argue that the birds have each

remembered a set—albeit a very complex set—of facts and

integrated these facts….

Thus demonstrating an extremely high level of complex

cognitive processing

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…

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..

because what you were doing was dissociated from the

events

This strategy isn’t perfect

because it still can’t separate out the bird as a

dispassionate observer from what is going on around it

But it is a start in the right direction

Researchers realized that scrub jays will steal from one another’s

caches…..

And that as a precaution, some jays will re-cache items

if their initial caching is observed by other jays….

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

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

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

These data begin to suggest that birds do have memories

that, if not specific to themselves,

Specifically….”if I pilfered another birds’ hoard whom I watched,

someone watching me may pilfer mine”

at least suggest some sense of attribution to others….

Of course, one can always come up with alternative

explanations….Something a bit less

mentalistic….any ideas???

Well…it seems that birds are acting as tho’ if they do

something, all other birds will do the same thing….

that is, generalization

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…

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

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

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

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?

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

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

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

Then, in the presence of the storer, the pilferer was given one

traywhile 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

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

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?

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

The original storers didn’t 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

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

They also ate a lot more after being in trials in which the observer ate some of their

caches

Here they weren’t just observed, but actively saw their caches being pilfered,

which is a fairly strong condition

In a separate study on other cachers, the Grey jay

This species would cache in front of a nutcracker because nutcrackers don’t pilfer

but wouldn’t cache in front of Stellar jays that do

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

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 didn’t care who recovered the

cache

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

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…

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

In yet another 2005 study (Animal Behaviour, Dally, Emery

and Clayton) looked at positional factors in social

settingsHere birds had a choice of

where to store under conditions of being watched or

not

sites were either close or far

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

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

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

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

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

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 wouldn’t be good either

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…

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?

Birds happily ate in view of the observer

So they weren’t simply avoiding another bird

And their behavior during caching wasn’t just due to

avoiding the other bird

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

Up close, pilferer can see only one site

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

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

Another problem is that the unseen site is always the further

one away….

So we still don’t 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….

Hence, another setup:

Seen and

unseen are now

equi-distant

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

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

In yet another study, jays seemed to understand which bird was the observer and react appropriately

So, for example, it didn’t care if its partner saw a cache (all in the

family)

But did react if a dominant saw it cache…

And the experimenters had problems because some birds stopped caching at all in the

presence of observersAnd 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

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 it’s always difficult to know for sure

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

Powdered nuts

No food

Later in day, learned that they could eat in B, too, but

just powdered nuts

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

But to make sure the birds weren’t 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

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!

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

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

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 seasonal…but could be episodic

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?

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

Would they learn, over training,

which food would be available after different

delays?

Note how this differs from the jays…

in what is available

Learning that something just disappears over time can be seen as just someone else

eating it up if you don’t get to it first

which is a subtle difference from something that has to

do with time per se

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

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

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

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…

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

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

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

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

Then they were tested after each of the ‘study’

trials

Now with first 1 hr and then 25 hr delays

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

trialAfter choosing the good food, the marker was removed to

encourage choice of the second site

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

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

The experimenters expected that, with time, the monkeys

would stop going to the preferred food after the 25 hr

delay….

But the monkey data didn’t quite work out that way….

Remember, the jays learned that worms got yuckky after 4

days

First of all, the monkeys didn’t 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….

But now, sometimes, instead of seeing a different

setup

which they had learned meant some trial-and-error

choicethey saw a familiar pattern…

How easy would it be to learn to ignore that????

We know that reversals are tough to acquire

And that’s what the monkeys had to learn…

So it’s likely there was a lot of interference going on

The lesioned monkeys more often examined unbaited

sitessuggesting that they indeed had

a poorer memory for the location of any kind of food…

good or bad

Toward the end of the paper, the authors admit that their training might have skewed the results

But they then discount the possibility…for 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?

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

Too, although Clayton couldn’t 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…

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 “know’’…i.e.,

metacognition

The suggestion is that metacognition is necessary for

episodic memory

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

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

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…

But in reality the animals reporting of uncertainty just allows them a third choice when a first choice doesn’t

surface quickly

It may not be any more conscious than any other type of choice they

are given

Some researchers—Suddendorf—argue 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?

Clearly the jays store for the future and monkeys do not…

But that doesn’t get to the idea of whether the jays’ behavior is

a mixture of instinct and knowledge

or self-awareness of what is individually needed

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

Wouldn’t it be great to ask Jay A where he thought Jay B would

search after A re-cached?

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;

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?

The take-home message is basically the cleverness of the

birds and the need for truly complicated experiments in

order to uncover their cleverness