Chapter 3 Elicited Behaviors & C.C PDF

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Dr. Stairs...

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Classical Conditioning o Was the first type of learning discovered.  Pavlov and his dogs o Deals with more reflexive type behaviors o This chapter will discuss them and talk about how these behaviors can be modified through learning Elicited Behaviors o Classical Conditioning involves elicited behaviors o What is an elicited behavior?  A behavior that is “drawn out” of an organism by the presentation of a stimulus  A behavior that is automatic and involuntary  Examples: sneezing, startling, salivating Reflexes o Basic form of elicited behavior o Are defined as a relatively simple, automatic response to a stimulus  Reflexes are closely tied to survival o Examples:  Startle response  Orienting response  Flexion response Reflex Arc o Simple reflexes are activated through a reflex arc o Is a neural structure that underlies many reflexes and consists of a sensory neuron, an interneuron, and a motor neuron o Reflex arcs allow us to respond much quicker to our environment Knee Jerk Reflex – Reflex Arc

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Tropisms and Orientation o Tropism—Involuntary forced movement  Movement of the entire body of the animal o Kinesis- Random movement in relation to the stimulus  Wood Lice – move until they get into a humid area – no mechanism to sense humidity o Taxis – direction of movement bears some relationship to the location of the stimulus  Maggot- will move away from a light source Fixed Action Patterns (FAP) o Similar to, but more complex than, reflexes o These are a fixed sequence of responses elicited by a specific stimulus  Is part of the repertoire of all members of a species – may be unique to species: species-specific behaviors  Experiments have shown that the animals ability to perform the behavior is not dependent on learning  In a sequence of behaviors, behaviors occur in a rigid order regardless of appropriateness in context  Once they start they will continue until complete, even in absence of a stimuli Sign Stimulus o Stimulus that sets the fixed action pattern into motion o Elicits a specific sequence of behaviors o There are often specific aspects of the sign stimulus that are required  Even poor imitations of the sign work – Stickleback o Surprisingly, unrealistic models of the sign will elicit a stronger response than the real sign Examples of FAPs

o Reaction Chains o Reaction chains differ from FAP

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 In FAP once behavior is initiated it goes to the end o In a reaction chain the progression from one behavior to the next depends on the presence of the appropriate sign stimuli  If stimulus is not present even in the middle of the chain, sequenced behavior will not occur o More varied then FAP – but also more adaptive Reaction Chain Example—Hermit Crab

o Simple Mechanisms of Learning o Habituation & sensitization tend to be seen across species  These processes probably have tremendous survival advantages o They help us sort information in our environment into two basic categories:  Currently relevant  Currently irrelevant Habituation o A decrease in the strength of an elicited behavior following repeated presentations of the eliciting stimulus  We tend to habituate to stimuli that are currently irrelevant and lowintensity o The first time the stimulus is present, the response will probably be most intense  Then the elicited response will gradually decrease  Examples: ticking of a clock, noise of traffic, consistent drone of music from neighbor’s dorm room o Habituation can disappear if the stimuli is not present for a long period of time Types of habituation o Long-term habituation – the response slowly decreases due to repeated stimulation

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 The response also slowly returns in the absence of repeated stimulation  Tends to result from widely spaced stimuli o Short term habituation: the response quickly decreases due to repeated stimulation  The response also quickly returns in the absence of repeated stimulation  Tends to result for narrowly spaced or continuous stimuli Stimulus Specific and Dishabituation o Habituation is stimulus specific  Any small change in the stimulus the response reappears: Coolidge effect o Dishabituation is the reappearance of a habituated response following the presentation of a seemingly irrelevant novel stimulus o Example:  A couple bum uglies in a novel hotel room to rekindle their romance Sensitization o An increase in the strength of an elicited behavior following repeated presentations of the eliciting stimulus  We tend to become sensitive to stimuli that are extremely relevant and high-intensity o Unlike Habituation, Sensitization often generalizes to other stimuli  Generalize? – What is this? o Examples:  War veterans’ responses to exploding artillery shells or the smell of something rancid What happens when the stimulus is of intermediate intensity? o A stimulus of intermediate intensity  Often result in an initial period of sensitization followed by habituation o Example:  Visiting a shooting range Evolutionary Perspective o It makes sense to become sensitized to some stimuli and habituated to others  Habituated to pressure of sitting in chair  If we didn’t would be really annoying  sensitized to the caress of a lover  associated with possible reproductive opportunities Opposing Reactivity o Habituation and sensitization represent two opposing tendencies of reactivity:  Strengthening versus weakening o Emotional responses can also oppose each other  falsely getting an A- in Org Chem  dog’s reaction to being shocked o Both events elicited a strong emotional response

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But when the event was withdrawn, an opposite response was elicited and then gradually disappeared Opponent-Process Theory of Emotions

o Opponent-Process Theory of Emotions o Explains the aftereffects of strong emotions o An emotional event elicits two competing processes:  a-process (or primary process) that is directly elicited by the event  b-process (or opponent process) that is elicited by the a-process and serves to counteract the a-process The A-Process o Correlates closely with the presence of the emotional event  When the shock is presented, heart rate immediately increase  When the shock is removed, heart rate immediately decreases The B-Process – Partially Hidden Process o Is slow to increase and slow to decrease  Slowly the b-process begins to moderate the a-process  Causing a slight decrease in heart rate before stabilizing – Compensatory response  When the shock is removed, the a-process immediately disappears  but the b-process only slowly declines Opponent-Process Theory of Emotions

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o What happens when the dog is shocked repeatedly? o With repeated presentations of the emotional event, the b-process increases in both strength and duration  the increase in heart rate during each shock becomes less and less extreme o Each time the shock is turned off, the dog’s heart rate drops more and more and takes increasingly longer to return to normal Opponent-Process –Repeated Stimulations

o Additional Examples o Dr. Stairs’ Bungee jumping  the more I bungee jumped the less scared (a process) and the more elated (b process) following o Drug Tolerance – the high (a process) decreases with repeated use, due to the strengthening of the opposing withdrawal effects (b process) Learning - Our survival depends on it! o Our environment changes constantly and is filled with a variety of stimuli o We need a mechanism by which we can adjust our behavior to changing conditions o Biological or evolutionary change is too slow

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We need a quick way to modify our behavior potential as a function of what we have experienced o Learning enables us to acquire some initial reactions to the environment  Also permits these reactions to change with changing circumstances o Our survival depends on our ability to learn relationships among environmental circumstance  This will allow us to anticipate environmental events and react appropriately and quickly to environmental conditions o The ability to relate the events to each other allows us to better anticipate the future  Greatly facilitating our chances of surviving Classical Conditioning o One mechanism for learning  Also called Pavlovian or respondent conditioning o One stimulus that does not elicit a response is associated with a second stimulus that does  As a result, the first stimulus also comes to elicit a response Pavlov’s Discovery o Ivan P. Pavlov (1849-1936)  a Russian physiologist o Credited with the first systematic investigations into classical conditioning o Originally, investigated salivation, the initial step in the digestive process o Found that salivation could be initiated with “psychic” factors  Visually seeing the food Pavlov’s Basic Procedures of Classical Conditioning o Purpose: To train a dog to salivate to the sound of a metronome o The dog was restrained in a harness, and a tube was inserted into an incision that had been made in its cheek  The saliva would run down the tube into a container where it could be precisely measured Pavlov’s Set-up

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o Unconditioned Stimulus (US) o Is a stimulus that naturally elicits a response  The food is called an unconditioned stimulus (US) o The dog did not have to learn to respond to the food Unconditioned Response (UR) o Is the response that is naturally elicited by the US  Before conditioning, the dogs would automatically salivate in response to the food in its mouth o Because salivation to food occurs naturally and does not require prior training (conditioning)  it is called an unconditioned response (UR) Neutral Stimulus (NS) o The neutral stimulus does not elicit a response o The sound of a metronome does not elicit salivation  Therefore said to be a neutral stimulus (NS) with respect to salivation During Conditioning o The sound of the metronome (NS) is presented just before the food (US) o The dog continues to salivate in response to the food (UR) o The sound of the metronome and the food are presented several times

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After Conditioning o The sound of the metronome elicits salivation  The NS has become the CS o The food does not have to be present for the dog to salivate when it hears the sound of the metronome Conditioned Stimulus (CS) o Is any stimulus that was initially neutral, comes to elicit a response because it has been associated with an unconditioned stimulus  The dog is now salivating to the sound of the metronome and this response required training (conditioning) o The sound of the metronome is now called a conditioned stimulus (CS) Conditioned Response (CR) o This Is the “new” response that is elicited by the CS  The CR is often similar to, but never identical to, the UR o Salivating in response to the sound of the metronome is now called a conditioned response (CR) Schematic Diagram: Before Conditioning o Food → Salivation o US UR o Metronome → No salivation o NS — Schematic Diagram: During Conditioning o Metronome: Food → Salivation o NS US UR o Each pairing of the NS and the US during conditioning is called a conditioning trial o Several conditioning trials are often needed before the NS becomes established as a CS o In this class during conditioning, the metronome is to be labeled an NS Schematic Diagram: After Conditioning o Metronome → Salivation o CS CR

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o Another Example o A child is bit by a dog  Dog: Bite → Fear  NS US UR  Dog → Fear  CS CR Describing Classical Conditioning o Often classical conditioning procedures fall into two categories:  Appetitive  Aversive o We also talk about classical conditioning being excitatory or inhibitory Appetitive Conditioning o The US is an event that is usually something that an organism seeks out o Examples:  Food, water, sexual stimuli o Sexual responses are classically conditioned o Knee high black boot study (Rachman & Hodgson, 1968)  Boot: Nude → Sexual arousal  NS US UR Aversive Conditioning o The US is an event that is usually something that an organism avoids o Examples:  An example shock, a painful bite, and an unpleasant odor

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o CR can occur quickly and requires only a few pairings for conditioning to occur o To survive, we have evolved in such a way as to quickly learn to dislike those events that cause pain or illness. Fear & Anxiety o Aversive conditioning accounts for many of our fears and anxieties. o When the fear is appropriate- as in learning to fear an angry dog that has bitten ussuch conditioning is beneficial o When the fear is inappropriate—as when we begin to fear all dogs—such conditioning can be problematic Measuring Fear o Measuring the level of fear can be difficult to record o An ingenious solution to this problem was developed by Estes and Skinner (1941)  It is known as the conditioned suppression o The level of fear can be assessed by the extent to which ongoing behaviors stop when fear-invoking stimuli is present and resumes when it is not  This is measured in the form of a suppression ratio. Suppression Ratio o The number of responses emitted during the CS period divided by the combined number emitted during the CS period and the number emitted during the same length period immediately preceding the CS o Suppression Ratio = # of CS responses o # of CS responses + # of pre-CS responses Classic Example o The rat is first trained to press a lever to obtain food.  When a steady rate of lever pressing has been established, a fear conditioning procedure is introduced o A 30-second tone is presented followed by a 1-second shock. Thus: o 30" Tone: 1" Shock  Fear/(-)pressing o NS US UR After Conditioning o As conditioning proceeds, however, the tone too will come to elicit fear, and the rate will stop pressing the lever when it hears the tone o 30" Tone  Fear /(-)pressing o CS CR Measuring the Rat’s Fear o The degree to which lever pressing for food is suppressed in the presence of the 30-second tone can be used as an indirect measure of the extent to which the tone elicits fear. o The rat emits 20 responses during the 30-second pre-CS period followed by 0 responses during a 30-second CS period.0  0/(0+20)= 0 o A suppression ratio of 0 indicates total suppression of responding.

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What if the rat…? o What if the rat emitted 10 responses during the CS period?  10 /(10 + 20) = 10/30 = .333 o What if the rat’s behavior didn’t change?  20 /(20 + 20) = 20/40 = .50 o The suppression ratio will generally vary between 0 and .5  lower ratio = less responding  less responding = greater suppression/effective conditioning. Transforming An Aversive Event o Classical conditioning can transform a normally aversive stimulus into an appetitive stimulus  Shocking a dog and then give it food o This same process might partially account for the development of masochistic tendencies.  Spanking and Whipping Excitatory Conditioning o Is defined as: conditioning in which the NS is associated with the presentation of US  The excitatory CS is usually labeled a CS+. o Examples:  the metronome is associated with the presentation of food  the dog is associated with a painful bite  the tone is associated with shock Inhibitory Conditioning o Is defined as – conditioning in which the NS is associated with the absence or removal of a US  The inhibitory CS is labeled a CS−. o Results in the CS coming to inhibit the occurrence of a response  The response is less likely to occur when that stimulus is present o Examples:  A no-vacancy sign is on at a motel  you are less likely to stop and get a room  presence of a leash on a dog  my nervousness of a dog fight decreases Temporal Arrangement of Stimuli o There are several ways to temporally arrange the presentation of the NS and the US:  Delayed Conditioning  Short and Long  Trace Conditioning  Simultaneous conditioning  Backward conditioning

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o Note the differences in effectiveness in producing the CR Delayed Conditioning o The onset of the NS precedes the onset of the US, and the two stimuli overlap  First present the tone (NS) – then while the tone is still on, present a shock (US) o This is the best arrangement for conditioning  especially when the interstimulus interval (ISI) is relatively short – Short Delay Conditioning o The interstimulus interval (ISI) is the time between the onset of the NS and the onset of the US o Intertrial interval (ITI) is the time from the end of one conditioning trial to the start of the next trial o Trace Conditioning o The onset and offset of the NS precede the onset of the US  The NS occurs before the US, and the two stimuli do not overlap o If you will, the organism has to “remember” the occurrence of the tone (“memory trace”) to be able to associate the NS and the US. o Example:

o Trace Vs. Delayed Conditioning o Trace conditioning can be almost as effective as delayed conditioning  The trace interval has to be relatively short  no more than a few seconds o If the trace interval is longer than that, conditioning is unlikely to occur o Trace Interval is the time between the offset of the NS and the onset of the US Simultaneous Conditioning o The onset of the NS and the onset of the US are simultaneous o Example:

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This procedure usually results in poor conditioning  the NS is no longer a good predictor of the US when they happen simultaneously Backward Conditioning o The US is presented first and the NS is presented later o Example:

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o o This is the least effective procedure for conditioning  Most of the time All Arrangements

o Backward Excitatory Conditioning o Backward excitatory conditioning can be achieved when the NS is a “biologically relevant” stimulus for fear  Many animals have an inherited predisposition to fear certain types of events o Example:  Rats have an inherited predisposition to fear snakes  Poisonous snakes have constituted a significant threat to rats  Even if the snake is presented after the shock, the fear elicited by the shock still becomes associated with the snake Backward Inhibitory Conditioning o Backward conditioning can work for inhibitory conditioning  A tone sounds just as a shock is being terminated  The tone essentially predicts the removal of a shock o The tone in this case may become a safety signal (CS–) that inhibits the occurrence of fear...