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Schedules of Reinforcement

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1 Schedules of Reinforcement
Mace, Pratt, Zangrillo & Steege (2011) Fisher, Piazza & Roane CH 4

2 Every response gets SR+ (CRF) vs EXT where each response gets 0
Rules that describe how responding will be reinforced are schedules of SR+ Every response gets SR+ (CRF) vs EXT where each response gets 0 Schedules are all possible arrangements between the extremes

3 Rules that describe how responding will be reinforced are schedules of SR+
Schedules in Context The discriminated operant Motivating operations Alter reinforcer or Punisher strength Prompt responses that in the past have functioned Discriminative stimuli: set the occasion for a given response to get reinforced Past history of SR+ or SR- ( Behavioral Mass for momentum concept)

4 Concurrently Available Operant Response Classes
CHOICE The matching Law R1 / R2 = SR+1 / SR+ 2 (approximately) The effects of reinforcement schedules are relative NOT absolute

5 Behavioral Dimensions Affected BY Schedules of Reinforcement
Ratio, Interval, & Time Contingencies Ratio = number of responses Interval = occurrences after time intervals Time = SR+ delivered independent of responding

6 Behavioral Dimensions Affected BY Schedules of Reinforcement
These contingencies can effect: Response Rate ( Frequency; interresponse time (IRT) Response Periodicity ( specific patterns of responding) Constant ( VI VR), Pausing, ( FR, FI) Suspension ( DRO), Celeration Resistance to Change ( Rate of deceleration following disruption) Extinction, Satiation, SR+ for alternative, Punishment, Dark-Key SR+, distraction

7 BASIC ( Single )SCHEDULES
See table 4.1 for the basic schedules Ratio: The number of responses to gain SR+ independent of time Fixed Ratio: The Number of responses is constant ( e.g., FR5 = 5 Rs Sr+) Variable Ratio: The Number of responses is variable ( VR 4 could be 2, 3 4,5 6,7,8 ) Also called Random Ratio schedules

8 Ratio SCHEDULES CRF = every response and rate is low
As the number of responses required increases so does rate Post reinforcement pause: a period of time after reinforcer delivery with no responding (increases with Ratio value) Ratio strain- responding stopping before the requirements are met Progressive VR Schedule: increasing the ratio after some number of successful performances on a starting ratio or previous ratio

9 Interval Schedules A passage of time (the interval) must elapse before responses are eligible for SR+ Limited hold: An additional passage of time, once the main interval has expired within which responding must occur to gain SR+

10 Interval Schedules Fixed Interval Schedules
The FIRST response after a fixed interval has passed gains SR+ Scallop, a typical increase in rate of responding towards the end of the interval Variable Interval schedules The FIRST response after a variable length interval has passed gains SR+

11 EXTINCTION SCHEDULES EXT+ = discontinuation of SR+ after positive reinforcement EXT- = discontinuation of SR+ after negative reinforcement Extinction Burst: an increase in responding early in EXT before rate decreases Seen in about 40% of all cases Side Effects of EXT- Bursting; increases in other behaviors, ( symptom substitution); aggression, elopement Therefore we typically continue to provide reinforcement in applied settings for alternative acceptable behaviors

12 Time Schedules SR+ is delivered according to some interval schedule but independent of responding Fixed Time (FT) or Variable time (VT) Note (Non-contingent Reinforcement (NCR) is a widely used term but is a misnomer Can be used to gain an “enriched environment” to increase motivation to respond As a control condition to show contingency effects of a SR+ for a given response To reduce undesirable behaviors Rapid suppression of responding, reduce motivation for extreme acts, removes extinction burst

13 Theoretical Implications of Time Schedules
The response-Reinforcer relationship is disrupted = one form of EXT MOs change from baseline (from when target behavior was happening, to a by-the-clock distribution. These abolish the extant consequences for the target behavior Research on these accounts has been unclear Other results have also demonstrated the cause of target reduction could be arbitrary reinforcement of other behaviors during FT

14 Differential Reinforcement Schedules ( DRO,DRA,DRI,DRL )
Differential Reinforcement : refers to SR+certain conditions and EXT for others These contingencies specify the dimensions of behavior that will and will not gain SR+ They may also define whether certain antecedent stimuli ( Sds and S deltas)must be present when a behavior occurs or does not occur Thus they involve Reinforcement ( positive and negative) and EXT Response dimensions subject to SR+ or EXT are: forms or topographies of response, response rates, Periodicity of responding and duration of responding. Fading: Refers to gradual changes in antecedent stimuli currently controlling a response Shaping: refers to reinforcement of successive approximations to a final response

15 Combined Schedules of Reinforcement
Two or more Basic schedules are present and are referred to as Component schedules. The 2 component schedules alternate, are available concurrently, or sequentially Multiple & Mixed: At least 2 components alternate : Mult are signaled Mixed are not. Concurrent &Conjoint schedules: Concurrent = at least 2 component schedules are available at the same time and are signaled, Conjoint are not signaled Chained and Tandem schedules: Two or more component schedules are arranged sequentially. Initial link and terminal link are the two schedules. Concurrent chained schedules involve choice between 2 chained schedules with differing terminal link consequences

16 Combined Schedules of Reinforcement: What is Studied
Behavioral Contrast. In a MULT schedule arrangement. Once responding is stable in each component, the increase or reduction of SR+ in the initial component will cause an opposite rate of responding change in the unchanged schedule ( see fig 4.2) Matching Theory: studies of “choice” in concurrent schedules Behavioral Momentum: an analogy to Momentum in Physics. A body in motion…. The general idea is that behavior maintained with higher magnitude of reinforcement tends to resist extinction better than behavior maintained at lessor magnitudes of SR+. Implications are that we can get behavior to occur by using “HI P” vs” Low P” demands and gradually insert lower P behaviors into Hi P sequences


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