Transcript Context Cues and Conditional Relations

Context Cues and Conditional Relations
Contextual Cues and Conditional Relations
• Discrete stimuli: a tone, a light
• Contextual Cues: background stimuli which can be a combination of
visual, auditory, olfactory, or other cues of the room or place.
• Control by Contextual Cues
– Conditioned place preference (CPP) paradigm
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to measure differences in motivation, reward, and aversion
Initial preference test: free to explore two adjacent locations
Training: provide food in one location but not at the other location
Final preference testing: free to explore two adjacent locations with no food
Often used to test new drugs for addictive potential
– Akins 1998: Contextual cues as a signal for sexual reinforcement.
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Context (cs) 1: orange with sand on the floor
Context (cs) 2: green walls and wire mesh floor
After initial preference test
Training in context :
– Group paired: in context 1 access to female as the US
– Group unpaired: homecage access to female
• Place preference tested on 5th and 10th trial see Fig 8.11
5th Trial
10th Trial
Before
Conditioning
The Principles of Learning and Behavior, 7e by Michael Domjan
Copyright © 2015 Wadsworth Publishing, a division of Cengage Learning. All rights reserved.
Conditioned place preference in children
• Affective processing, which can influence attention, motivation/reward, and
emotional regulation
• difficult to test in young children
• when trying to determine these functions in a non-verbal child
• establishing capacity in developing executive function
• Using conditioned place preference (CPP)
• in human adults drugs, music or food have been used as US
• testing affective processing in children, ages of 30–55 months
• CS: child-friendly arena, a castle
• US
• engaging toys such as musical toys
• less engaging toys such as puzzles and books
Conditioned place preference successfully established in typically
developing children
• Initial Preference Test
• The child was provided 6 min to explore both training rooms
• Training Trials
• The child was then given access to only one room of the arena with either
the more or less engaging US,
• Final Preference Test
• The child was allowed to freely explore both training rooms for an additional
6 min.
• Results:
• initial preference test
• no differences in mean time spent in each room
• Final Preference Test
• there was a significant room preference
• CPP scores were not correlated with scores on the Mullen Scales of Early
Learning (MSEL)
• A measure cognitive ability and motor development
Contextual Cues and Conditional Relations
• Contextual stimulus control is possible without reinforcement for
the context
• Thomas, Mckelvie & Mah (1985)
– Context 1 (standard chamber): S+ Vert line S- Horz line
– Vert line (S+) pecking (R) to get food (O)
– Horz line (S-) no food
– Context 2 (different light & noise in chamber) : S+ Horz line S- Vert line
– Note: within subject design, each pigeon was trained in both contexts
• Discrimination training produced Generalization Gradients
appropriate to context see Figure 8.12
• Context can activate memories of S+/S- associations
• Pigeons learned a conditional relationship
• If Context 1 then recall of S+ Vert line
• If Context 2 then recall of S+ Horz line
• Generalization test across different degrees of line angle
horz
vert
The Principles of Learning and Behavior, 7e by Michael Domjan
Copyright © 2015 Wadsworth Publishing, a division of Cengage Learning. All rights reserved.
Control by Conditional Relations
• In the Thomas, Mckelvie & Mah (1985) example
– context can acquire conditional stimulus control over (R-O)
– Context acts as a modulator for the (R-O) relationship
– Similar to other examples of instrumental conditioning such as
• discrimination training with S+ (1000Hz) and S- (950Hz)
• Modulators can also control (CS-US) in classical conditioning
• Colwill (2005) goal tracking procedure
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Light then Noise (CS) --- Food (US)
No Light Noise (CS) --- No Food
Measure number of times head went into the food cup
More responding to light-noise sequence then just noise
Very little responding to just the light see figure 8.15
The light facilitates responding to the noise CS
The Principles of Learning and Behavior, 7e by Michael Domjan
Copyright © 2015 Wadsworth Publishing, a division of Cengage Learning. All rights reserved.
Control by Conditional Relations
• Modulator terminology in Pavlovian conditioning
– Holland in the early 1980s called them occasion setters
– Rescorla called them facilitators
• Procedures used by Colwill (2005)
– Produces positive modulator light increases responding so this could be called
positive occasion setting
– Procedure for inhibitory conditioning fig 3.11 produces inhibitory modulator so this
could be called negative occasion setting
• Modulation versus Configural Conditioning
– when light and noise were presented as a sequence act as Modulators
– Light for 15 seconds then noise for last 5 sec
• Light comes first and then overlaps CS-US relationship
– configural cue examples we covered earlier (pages 219-220) are presented together
“simultaneous” a light/noise compound to model complex stimuli
Distinction Between Excitation and Modulation
• Modulators have properties that differ from those of conditioned
excitation.
• Modulators can set the occasion for a CS to elicit a response
without itself eliciting that response.
• Conditioning simple excitatory properties to a stimulus does not
allow it to function as a modulator.
• Presenting an established modulator by itself repeatedly
(extinction) does not reduce its ability to modulate a CS-US relation,
because it signals a CS-US relation, not the individual occurrence of
the CS or the US.
Distinction Between Excitation and Modulation
• Modulators can have properties that differ from those of conditioned
excitation.
• Colwill (2005)
• Light (modulator) then Noise (CS) Food (US)
• No Light (modulator) Noise (CS) Nothing
– The light does not become excitatory
• Can be Tested with an extinction procedure
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typically for an excitatory CS such as noise followed by food
repeated presentations of the CS noise by itself would produce extinction
presenting the light modulator repeatedly by itself
has no effect on the light acting as an excitatory
• An excitatory CS produces an expectation of the US
• A modulator produces expectation of CS-US relationship, sets the occasion