Sac State PSYC 104 - Escape Avoidance and Punishment

Unformatted text preview:

1Chapter 9 - Escape, Avoidance &PunishmentLecture Outline• Escape & avoidance– Two-factor theory of avoidance– Avoidance conditioning & phobias– Avoidance conditioning & OCD• Punishment– Types of punishment– Problems with punishment– Effective use of punishment– Theories of punishment• Effects of non-contingent punishment– Learned helplessness– Masserman’s experimental neurosis2Escape & Avoidance• Negative reinforcement– Removal of an aversive stimulus that leads to increase inbehavior• Escape– Performance of a behavior terminates exposure to theaversive stimulus– Shock (SD) : Cross Barrier (R) → Terminates ShockExposure (SR)•Avoidance– Performance of a behavior prevents exposure to the aversivestimulus– Light (SD) : Cross Barrier (R) → Prevents Shock Exposure(SR)Escape & AvoidanceEscapeAvoidance3Escape & Avoidance• Two-factor theory of avoidance (Mowrer, 1947)– Two processes involved in learning escape response1.Light (CS) : Shock (UCS) → Fear (UCR)Light (CS) → Fear (CR) (fear response elicited by the CS)2. Light (SD) : Cross Barrier (R) → Reduced Fear (SR) (avoiding the CS is negatively reinforced byreduction in fear)– Theory predicts that avoidance responding is performedto the extent thatEvidence for two-factor theory• Kamin (1957)– Fours groups of rats in a 2-chamber avoidanceapparatus• Group 1 – avoids shock & terminates (CS) signal• Group 2 – avoids shock & signal (CS) remains on• Group 3 – receives shock & terminates (CS) signal• Group 4 – receives shock & signal (CS) remains on– Two-factor theory – Prediction•4• High rate of respondingin group that couldterminate CS & avoidshock• Poorer rate ofresponding in group thatcould not terminate CSbut could avoid shock• Support for two-factortheory!!!20100408060010 20 30 40 50 60 70 80 90 100Trials Avoidance Responses %Avoids shock CS remains onAvoids shock Terminates CSReceives shockTerminates CSReceives shockCS remains onEffect of Delay of CS Removal•Delay of reinforcement reduces effectiveness ofreward• If termination of feared stimulus is reinforcingthen delay between response and termination ofthe CS should reduce avoidance responding• Kamin (1957)– Fours groups of rats in a 2-chamber avoidanceapparatus• Group 1 – CS terminated immediately• Group 2 – CS termination after 2.5 s delay• Group 3 – CS termination after 5 s delay• Group 4 – CS termination after 10 s delay5Results• Effectiveness of CStermination to supportavoidance wasdecreased by increasingdelay• Results suggest that thesource of reinforcementin avoidanceconditioning was thereduction of feargenerated by thetermination of the CS• More support for two-factor theory!!!01020304050607080901-1010-2020-3030-4040-5050-6060-7070-8080-9090-100TrialsAvoidance Responses %No Delay2.5 s Delay5 s Delay10 s DelayEvidence against 2 factor-theory• Solomon, Kamin & Wynne (1953)– Conditioned avoidance responding in dogsLight (CS) : Shock (UCS) → Fear (UR)Light (CS) → Fear (CR)(fear response elicited by the CS) Light (SD) : Cross Barrier (R) → Reduced Fear (SR)– Shock then disconnected• Dogs jump barrier for 100s of trials to avoid shock!!!• But…(R) should extinguish because CS occurred without theUS– Perhaps exposure to CS too brief for fear to extinguish(anxiety conservation hypothesis)6Evidence against 2 factor-theory•Herrnstein & Hineline (1966)– Rats placed in Skinner box– Electric shock delivered randomly (probability = .3 forevery 2-second period that elapsed)– Probability of shock reduced from .3 to .1 if lever pressed– Rats could not avoid or escape shock…just reducenumber of shocks received– Most rats learned the task and kept lower rate of shockprobability– Problem for two-factor theory: avoidance learning inabsence of CS– Avoidance learning can be explained by one factor –reduction in shock rateOne-factor Theory•One-factor theory–Avoidance is negatively reinforced by the lowerrate of aversive stimulation to which it isassociated– Reduction of aversive stimulationaccompanying avoidance maintains avoidance• Which theory is correct???– That depends!!!– Several processes seem to be involved inavoidance learning7Avoidance conditioning &phobias• Phobia– Irrational fear of specific object or situation– Fear is disproportionate to real threat– Acquisition – Pavlovian conditioningElevator(CS) : Feeling Trapped (UCS) → Fear (UCR) Elevator(CS) → Fear (CR)– Maintenance – Avoidance (negative reinforcement) Elevator (SD) : Avoid Elevator (R) → Reduced Fear (SR)• Can laboratory analogues of avoidance learningexplain phobias in humans???Avoidance conditioning &phobias•Mineka (1985)– Two limitations to applying analogues of avoidancelearning in explaining phobias in humans1. In experimental studies the animal avoids the US, inhumans the CS is avoided2. In experimental studies avoidance behavior takes several trials to develop (& often unreliable), in humans asingle trial is sufficient (& very reliable)•Stampfl (1987)– Argued previous avoidance-conditioning procedurescould not address these issues8•Stampfl (1987)– Developed procedure to establish:1. Fear with single, brief CS-US pairing2. Avoidance of the CS & US3. Successful avoidance on 100% of trialsStart PhotocellsDarkCompartmentDarkSidewallsCon veyerBelt• Session 1– Rat explores the alleyway– Preference for dark compartment but given strong foot-shock after arrival– Rat runs to opposite end of compartment– 3 minute delay then conveyer belt begins to return ratsto dark compartment– Rats runs to opposite end breaks photo-beam →conveyer stops for 3 minutes– After 3 minutes conveyer starts again• Session 2– Response requirement changed from FR1 to FR10– Rats had to pass photo-beam 10 times to stop belt• Results– Ss travelled slightly past photo-beam before runningback - avoided CS (black compartment) & US (shock)– Successful avoidance on 100% trials for < 1000 trials– Only 1 CS-US pairing (single trial learning)9Summary of Stampfl study• Summary–Avoidance response occurs early in thebehavioral stream (minimises effort required)– Early responding reduces likelihood thatresponse can extinguish (no exposure to US ispossible)–Minimal effort is required to make avoidanceresponse and behavior is resistant to extinction– Phobic response is maintainedAvoidance conditioning & OCD•


View Full Document

Sac State PSYC 104 - Escape Avoidance and Punishment

Documents in this Course
Load more
Download Escape Avoidance and Punishment
Our administrator received your request to download this document. We will send you the file to your email shortly.
Loading Unlocking...
Login

Join to view Escape Avoidance and Punishment and access 3M+ class-specific study document.

or
We will never post anything without your permission.
Don't have an account?
Sign Up

Join to view Escape Avoidance and Punishment 2 2 and access 3M+ class-specific study document.

or

By creating an account you agree to our Privacy Policy and Terms Of Use

Already a member?