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Conditional learning:
Switching associations
Are there any types of learning that associative theory cannot explain?
"Red Light"
"Red Light"
"Red Light"
sometimes what the CS is associated with depends on the context...
e.g. lexical ambiguity task:
ambiguous word e.g. bank
subject must define based on semantic context
- country walk? going shopping?
e.g. Continuous performance test (CPT)
A x A y B y B y B x A y B y A y A x B x B y
e.g. Continuous performance test (CPT)
A x A y B y B y B x A y B y A y A x B x B y
must respond to x if preceded by A (not B)
i.e. A: x+, y- B: x-
e.g. Continuous performance test (CPT)
A x A y B y B y B x A y B y A y A x B x B y
must respond to x if preceded by A (not B)
must respond to y if preceded by B (not A)
i.e. A: x+, y- B: x-, y+
e.g. Stroop!
e.g. Stroop!
redyellow
green
Patients with schizophrenia have been reported to have difficulty on such tasks:
Lexical ambiguity e.g., Cohen et al, 1988
Continuous performance test e.g., Cornblatt et al, 1989
Stroop e.g., Wysocki & Sweet, 1985
Patients with schizophrenia have been reported to have difficulty on such tasks:
Lexical ambiguity e.g., Cohen et al, 1988
Continuous performance test e.g., Cornblatt et al, 1989
Stroop e.g., Wysocki & Sweet, 1985
... and in rats performance on such tasks disrupted by amphetamine
-- restored by D1/D2 receptor antagonists
e.g. Dunn et al., 2005 Instrumental biconditional task:
Tone: Left lever --> food Right lever --> no food
Click: Left lever --> no food Right lever --> food
0
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1
Mean Lever presses per trial
CorrectIncorrectSeries3Series4Series5Series6Series7Series8Series9Series10Series11
control 0.5 1.0 1.5
dose of amphetamine
So how are these tasks performed? They cannot be the result of simple associations
Tone: Left lever --> food Right lever --> no food
Click: Left lever --> no food Right lever --> food
Tone and click paired with food
Left and Right paired with food
One interpretation is that they are a type of conditional learning
Conditional cues are interesting because they are not just Pavlovian CSs...
- occasion setters do not extinguish
- get better occasion setting when occasion setter is not a good predictor of the US
- Simultaneous: light+tone-food tone-- Serial: light……tone-food tone-
so what are they? beyond the association...
Outline of lecture:
Consider how conditional cues work
Consider how conditional cues form
Look at what conditional cues can do -- example of therapeutic implications
Illustrate with experiment with pigeons (Bonardi 1996)
Click: red-->food red -->nothing
Flash: green -->food green -->nothing
Birds trained with two occasion setters - 10-sec presentations of diffuse cues - followed by 5-sec presentation of a keylight
Click redfood
red
Question 1:
How do they work?
red food
Click
?
red food
Click
Rescorla’s modulation theory (Rescorla, 1985)
Whenever a CS is presented, it must activate the US representation to get a conditioned response.
If the click is a positive occasion setter, it lowers its activation threshold -- making it easier for the CS to activate.
red food
Click
Holland’s and-gate theory (1983)
The click acts as an and-gate, allowing activation to flow from the CS to the US, and so elicit a conditioned response.
Click: red-->food red -->nothing
Flash: green -->food green -->nothing
These theories make differentpredictions about transfer
- will the clicker elevate responding to the green keylight?
red food
green
These theories make differentpredictions about transfer
- will the clicker elevate responding to the green keylight?
Hollandsays no
Rescorlasays yes
Click
e.g. (Bonardi 1996)
Click: red-->food red -->nothing
Flash: green -->food green -->nothing
Test:
Same: Click: Red Flash : Green
Diff: Click: Green Flash : Red
0
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80
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Responses per minute
SameDiffTarget alone
Click does elevate responding to green keylight
......so is Rescorla right?
but this transfer could be generalisation - red/green confusion
.... so transfer not conclusive evidence for Rescorla
0
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Responses per minute
SameDiffTarget alone
Plus Rescorla predicts click should be equally good with red and green - and it isn't...
So can Holland's theory do better?
0
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Responses per minute
SameDiffTarget alone
Holland predicts incomplete transfer - so is he right?
-- or is this generalisation decrement?
Click: red-->food red -->nothingFlash: green -->food green -->nothing
Test:
Same: Click: Red Flash : GreenDiff: Click: Green!!! Flash : Red!!!
Novel stimulus combination disrupts responding on Diff trials????
(Bonardi 1996) Tests this possibility:
Group OS - Click and Flash are occasion setters
Click: red-->food red -->nothingFlash: green -->food green -->nothing
Test:
Same: Click: Red Flash : GreenDiff: Click: Green Flash : Red
Expect more responding on same than different
(Bonardi 1996) Tests this possibility:
Group pseudo OS - Click and Flash are NOT occasion setters
Click: red-->food red -->foodFlash: green -->food green -->food
Test:
Same: Click: Red Flash : GreenDiff: Click: Green Flash : Red
If previous result generalisation decrement, predict same hereIf previous result occasion setting, do not...
Group OS Group POS
0
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90
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Responses per minute
SameDiffTarget aloneSeries4Series5Series6Series7
So it's not generalisation decrement...
can you think of a reason why you might get more respondingon same than on different trials? Wagner is a clue....
So occasion setter is specific to the particular CS...
(and Rescorla himself has generated evidence against his theorye.g. Rescorla, 1991a; 1991b) - so probably Holland wins...
But how about the US? is click more effective with CSs pairedwith the same US as red?
red food
Click
So occasion setter is specific to the particular CS...
(and Rescorla himself has generated evidence against his theorye.g. Rescorla, 1991a; 1991b) - so probably Holland wins...
But how about the US? is click more effective with CSs pairedwith the same US as red?
red food
Click
green different food
?
Morell & Davidson, 2002
Light: tone -->suc Light- tone-
Group Same US click -->sucorGroup Diff US click -->oil
Test: Light tone Same CS Same US
Light click (group Same) Diff CS Same US
Light click (group Diff) Diff CS Diff US
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Responses per minute
CompoundFeatureTargetSeries4Series5Series6Series7Series8Series9Series10Series11
Same CS Diff CS Diff CSSame US Same US Diff US
So if you change the US get dramatically reduced effect
So occasion setter is specific to the particular US as well...
Conclude: evidence supports Holland - acts on association
- do get transfer, based on CS-CS and US-US generalisation
- if change anything in association, transfer attenuated
red food
Click
green different food
Question 2:
How do they form?
If this is not an association, then where does it come from?
red food
Click
Where do associations come from? Associative learning explained by Rescorla-Wagner model (among others)
Shows certain characteristics - e.g. blocking:
A-->food AX --->food X? learning about X poor
red food
Click
Does occasion setting show blocking?
Biographie de Al CAPONE :
Ni McGurn, ni Capone ne pensèrent un seul moment que l'assassinat planifié de Bugs Moran serait un événement qui deviendrait notoire pour plusieurs
dizaines d'années. Capone se prélassant en Floride, comment pouvait-on le rendre responsable du meurtre d'un contrebandier ? «Machine Gun» McGurn avait le plein contrôle de l'attaque. Il rassembla une équipe de première classe composée gens de l'extérieur : Fred «Killer» Burke en était le chef et était assisté par un tirreur du nom de James Ray. Deux autres membres étaient John scalise et Albert Anselmi, qui avaient été
utilisés pour le meurtre de Frankie Yale. Joseph Lolordo faisait aussi partie du groupe, tout comme
Harry et Phil Keywell, du Purple Gang de Détroit. Le plan de McGurn était créatif. Un contrebandier invita les membres du gang de Moran à le rencontrer dans un garage afin de leur offrir du whisky de qualité à un prix imbattable. La livraison allait être faite à 10h30, le
14 février. Les hommes de McGurn allaient les attendre vêtus d'uniformes de police et d'imperméables,
donnant l'impression qu'un raid allait se dérouler.
Blocking of occasion setting (Bonardi 1991)
Group Exp
Click: noise-->food noise -->nothing
Rats: 3-min presentation of a click, with embedded reinforced 5-s noise presentations. Outside click noise nonreinforced
Click
noise
+ + + + +
Blocking of occasion setting (Bonardi 1991)
Group Exp
Click: noise-->food noise -->nothing
Group Con
Click: noise / food noise -->nothing
Click
noise
+ + + + +
Blocking of occasion setting (Bonardi 1991)
Group Exp
Click: noise-->food noise -->nothing
Group Con
Click: noise / food noise -->nothing
then allClick+Light: noise-->food noise -->nothing
test all Light: noise ?? noise??
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Responses per minute
noise in ITI
noise infeatureSeries3
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so blocking of occasion settingoccurred - learningabout L blocked only when Clickan occasionsetter
Group E Group C
And just in case you weren't convinced...
similar experiments have been performed to demonstrate the parallel effect with Sd's
Click
response
+ + + + +
Colwill & Rescorla, 1990
again looks at blocking, but relies on principle of unblocking
mismatch between outcomes in two stages attenuates blocking
e.g. Dickinson Hall and Mackintosh, 1976
A-->sh AX --->sh X? learning poor
A-->sh AX --->sh-sh X? learning restored
A-->sh-sh AX --->sh-sh X? learning poor
A-->sh-sh AX --->sh X? learning restored
Colwill & Rescorla, 1990
noise (Sd) lever
chain
sucrose
foodnoise (Sd)
Trained two further Sd's in compound with the noise:
Stage 2:
Same
Different
noise (Sd) lever
chain
sucrose
foodnoise (Sd)
lever
chain
sucrose
food
lever
chain sucrose
food
noise (Sd)
noise (Sd)
light (Sd)
flash (Sd)
will the Noise block the Flash or the Light ??
Stage 2:
Same
Different
noise (Sd) lever
chain
sucrose
foodnoise (Sd)
lever
chain
sucrose
food
lever
chain sucrose
food
noise (Sd)
noise (Sd)
light (Sd)
flash (Sd)
animals learn the same thing about the noise in Stage 1 as they do about about the light in Stage 2
Same ---> blocking
but animals learn different things about the noise in Stage 1 and about the flash in Stage 2
Different--> unblocking
therefore predict more control by the flash than by the light
Flash
Light
this means occasion setters show blocking
it also demonstrates forcibly that occasion setters convey
information about CS/US combinations
-- if combination changed, learning differs...
this is all consistent with Holland's theory
What does all this mean?
One suggestion -- Hierarchical account: CS-->US association can act as independent associable unit, and occasion setter becomes associated with it (e.g. Bonardi, 1998)
associative learning, but not as we know it...
is there any evidence that CS-->US association can act as an independent unit?
food
Click
red
A x B x C y
D y
C no shock
A shock
D ? Fear CR
B ? Fear CR
Acquired equivalence experiment as a test of this idea
Stimuli become more similar if trained in the same way
x, y food and no food
based on original demonstration by Honey & Hall, 1989
y
C no shock
A shock
x
A x B x C y
D y
An explanation in terms of mediated conditioning:
An association can form between x and shock even though x is only being thought about
y
C no shock
A shock
x
y
D no shock
B shock
x
A x B x C y
D y
An explanation in terms of mediated conditioning:
now when you present B, it makes you think about shock via x
some experiments have tested x and shown this to be true
A x+ y- B x+ y-
C y+ x-
D y+ x-
C no shock
A shock
D ? Fear CR
B ? Fear CR
Now consider a more complex version (e.g Honey & Watt, 1998)
x and y are paired with paired with food or not
y +
C no shock
A shock
x +
A x+ y- B x+ y-
C y+ x-
D y+ x-
A more complex explanation in terms of mediated conditioning:
y +
C no shock
A shock
x +
y +
D no shock
B shock
x +
A x+ y- B x+ y-
C y+ x-
D y+ x-
A more complex explanation in terms of mediated conditioning:
If x+ and y+ associations act as independent associable units, they should act just like x and y in the simple task
0.3
0.35
0.4
0.45
0.5
0.55
0.6
0.65
1 2 3
Suppression ratios
DB
It works.. but is this really because x+ and y- signal shock?
Phase 1
A x+ y- B x+ y-
C y+ x-
D y+ x-
A x
10s
+
10s
A,B,C,Dvisual
x, yauditory
USfood pellet
Bonardi & Jennings 2008
Phase 1 Phase 2
A ---> shock
C ---> no shock
A x+ y- B x+ y-
C y+ x-
D y+ x-
Test 1
x+ ---> ?
y+ ---> ?
If x+ signals shock it should evoke more fear than y+...
x
10s
+
10s
x, yauditory
USfood pellet
10s
P Q
Suppression ratio Q / (P+Q)
Test fear elicited by x+ and y+
Response baseline
432100.2
0.4
0.6
0.8
x+
y+
Trials
Suppression ratios
Effect of trial type p=.020
Effect of Trial type p=.03
432100.4
0.5
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0.7
0.8
0.9
y-
x-
Trials
Suppression ratios
... and y- should evoke more fear than x-
Conclude:
CS-->US association can act as independent associable unit
So is hierarchical account right?
One alternative suggested by Honey & Watt 1998
Another by configural theory
A x+ y- B x+ y-
food
A
x
no foody
B Hierarchical account saysthat A and B both acquire control over the x-->food and y-->food associations
A,B are occasion setters
x,y are CSs
Different things!
A x+ y- B x+ y-
food
A
x
B
Honey and Watt saythat A and B and x become linked to a hidden unit that is associated with food (same for A, B, y and no food)
A and B and x and y play exactly the same roles!
no food
A
y
B
A x+ y- B x+ y-
food
Configural theory says a blend of A and x, and of B and x, becomes associated with food, and blends of Ay and By become associated with no food
Normal classical conditioning with blended representations
no food
A x
B x
B y
food
no food
A y
So which is right?! Jury's out on hierarchical versus Honey & Watt (but we are working on it..) -- issue is whether occasion setters are special or not.
There is some evidence on deciding between hierarchical or configural theory -- e.g. Morell & Davidson 2002
Light: tone -->suc Light- tone-
Group Same US click -->sucGroup Diff US click -->oil
Test Light/tone Light/click(sameUS) Light/click(diff US) 0
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Responses per minute
CompoundFeatureTargetSeries4Series5Series6Series7Series8Series9Series10Series11
Same CS Diff CS Diff CSSame US Same US Diff US
foodLighttone
Lightclick
?
Lightclick
Train
Test same CS same US
diff CS same US
diff CS diff US
Lighttone
?
?
foodLighttone
Lightclick
?
Lightclick
Train
Test same CS same US
diff CS same US
diff CS diff US
Lighttone
?
?
Configural theory says responding at test depends on similarity of training and test configures
but these do not change with identity of US
so last two conditions will be the same
Train
Test same CS same US
diff CS same US
diff CS diff US
..but what if identity of US encoded in configure?
then configural theory could explain these results --
Lightclicksuc
?
Lightclick oil
?
foodLighttonesuc
?Lighttonesuc
now configures more different if US changes
But how about this - work with rats not yet published...
Jewel: click-->suc click--> Jewel-->
tone --> suc buzz --> oil
Test Jewel tone Jewel buzz
Jewel click
suc
this part like Morell and Davidson
same feature, different target CSconfigural theory predicts less responding when USs differ
Jewel: click-->suc
tone --> suc buzz --> oil
Test Jewel tone Jewel buzz
sucJewelclick suc
Jeweltone suc
Jewelbuzz oil
hierarchical theory predicts the same, because the training andtest associations are more different when USs differ
Jewel: click-->suc
tone --> suc buzz --> oil
Test Jewel tone Jewel buzz
responding higher on same than on different trials
both configural and hierarchical theory can explain these results
6
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8.5
9
9.5
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Test sessions
Responses per minute
SameDifferent
But how about doing converse...same target CS different "occasion setter" (actually just a CS)
Jewel: click-->suc click--> Jewel-->
dark... --> suc flash... --> oil
Test dark click flash click
test compounds still differ by one or two components so configural theory predicts exactly the same as before
Jewel: click-->suc
dark... --> suc flash... --> oil
Test dark click flash click
sucJewelclick suc
darkclick suc
flashclick oil
but hierarchical theory does not predict anything because test compounds do not include occasion setters
Jewel: click-->suc
dark... --> suc flash... --> oil
Test dark click flash click
responding nonsignificantly higher on different trials -
configural theory predicted the opposite result
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10
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12
13
1 2 3 4
Test sessions
Responses per minute
SameDifferent
Conclude:
Some evidence against configural theory
But no discrimination yet between hierarchical account and Honey & Watt
A hot topic! Are occasion setters special or not?
Further questions: what else can occasion setters do?
when a CS signals a US animals learn this relation and respond
they also learn when the US will be presented - timing
Tone (20 sec) --> food
432100
10
20
30
40
50
60
Adapted from Roberts (1982)
Five-second blocks
Mean responses per minute
Can occasion setters tell the rat when the US will occur?
Short trials: Click: Light (6)+ Noise: Dark (6+)
Long trials: Click: Dark (30)+ Noise: Light (30+)
Can occasion setters tell the rat when the US will occur?
Short trials: Click: Light (6)+ Noise: Dark (6+)
Long trials: Click: Dark (30)+ Noise: Light (30+)
201816141210864202
4
6
8
10
12
Short trials
Long trials
End of training
Two-second bins
Mean responses
Bonardi & Jennings 2007
Then give probe trials - present Light and Dark for 90 seconds to look for the point of maximum responding
Short trials: Click: Light (6)+ Noise: Dark (6+)
Long trials: Click: Dark (30)+ Noise: Light (30+)
Expect peak responding to be at 6s on short trials and 30s on long trials
40302010010
20
30
40
Short trials
Long trials
Data from probe trials
Two-second bins
Mean responses per bin
Can occasion setters tell the rat when the US will occur?
Apparently yes!
Conditional learning and Drug tolerance (Ramos et al., 2002)
Ethanol induces hypothermia, to which tolerance develops and this conditions to other cues that are present
Investigated effect of extinguishing cues.
Critical fact: CSs extinguish when presented alone
occasion setters do not
Flash (injection -->ethanol) injection -->saline
Tolerance conditions to Flash
Flash
(injection -->ethanol) injection -->saline
When Flash and injection simultaneous (not good for occasion setting) extinction of Flash removed its tolerance effects
Flash (injection -->ethanol) injection -->saline
When Flash and injection serial (good for occasion setting) extinction of Flash had no effect
So understanding occasion setting gives important information on the development of tolerance in drug addiction...
References
Bonardi, C. (1991). Blocking of occasion setting in feature-positive discriminations. Quarterly Journal of Experimental Psychology, 43B, 431-448.
Bonardi, C. (1996). Transfer of occasion setting: The role of generalization decrement. Animal Learning and Behavior, 24, 277-289.
Bonardi, C. (1998). Conditional learning: An associative analysis. In P.C. Holland and N.A. Schmajuk (Eds.) Associative learning and cognition in animals: Occasion setting. Washington, D.C.:APA
Bonardi, C., & Jennings, D. (2007). Occasion setting of timing behaviour. Journal of Experimental Psychology: Animal Behavior Processes, 33, 339-348.
Bonardi, C., & Jennings, D. (2008). Learning about associations: Evidence for a hierarchical account of occasion setting. Journal of Experimental Psychology: Animal Behavior Processes, in press.
Cohen RM, Semple, WE, Gross, M, Mordahl, TE, Holcomb, HH, Dowling, MS, & Pickar, D (1988) The effect of neuroleptics on dysfunction in a prefrontal substrate of sustained attention in schizophrenia. Life Sciences, 43, 1141-1150.
Cornblatt, BA, Lenzenweger, MF, Erlenmeyer,-Kimling, L (1989). A continuous performance tist, idential pairs version. ll Contrasting attentional profiles in schizophrenic and depressed patients. Psychiatry Research, 29, 65-85.
Colwill, R.M., & Rescorla, R.A. (1990). Evidence for the hierarchical structure of instrumental learning. Animal Learning and Behavior, 18, 71-82.
Dickinson, A, Hall, G, & Mackintosh, NJ (1976). Surprise and the attenuation of blocking. Journal of Experimental Psychology: Animal Behavior Processes, 2, 313-322.
Dunn, M., Futter, D., Bonardi, C., & Killcross, A.S. (2005). Attenuation of D-amphetamine-induced disruption of conditional discrimination performance by alpha-flupenthixol. Psychopharmacology, 177, 296-306.
Holland, P.C. (1983). Occasion setting in Pavlovian feature-positive discriminations. In M.L.Commons, R.J. Herrnstein & A.R Wagner (Eds.) Quantitative analyses of behavior: Discrimination Processes (Vol. 4: pp.183-206). New York: Ballinger.
Honey, R.C., & Hall, G. (1989). Acquired equivalence and distinctiveness of cues. Journal of Experimental Psychology: Animal Behavior Processes, 15, 338-346.
Honey, RC, & Watt, A. (1998). Acquired relational equivalence: Implications for the nature o associative structures. Journal of Experimental Psychology: Animal Behavior Processes, 24, 325-334.
Morell, J.V., & Davidson, T.L. (2002). Transfer across unconditioned stimuli in serial feature discrimination training. Journal of Experimental Psychology: Animal Behavior Processes, 28, 83-96.
Ramos, BMC, Siegel, S, & Bueno, JLO (2002). Occasion setting and drug tolerance. Integrative Physiological and Behavioral Science, 37, 165-177.
Rescorla, R.A. (1985). Conditioned inhibition and facilitation. In R.R..Miller & N.E.Spear (Eds.) Information Processing in animals: Conditioned inhibition. (pp.299-326). Hillsdale N.J. Erlbaum.
Rescorla, R.A. (1991a). Combinations of modulators trained with the same and different target stimuli. Animal Learning and Behavior, 19, 355-360.
Rescorla, R.A. (1991b). Transfer of inhibition and facilitation mediated by the original target stimulus Animal Learning and Behavior, 9, 293-303.
Swartzentruber, D. (1995). Modulatory mechanisms in Pavlovian conditioning. Animal Learning and Behavior, 23, 123-143.
Wysocki, MS, & Sweet, JJ (1985). Identification of brain damaged schizophrenic, and normal medical patients using a brief neuropsychological screening battery. International Journal of Clinical Neuropsychology, 7, 40-49.