PARAMETRIC ANALYSIS OF DELAYED PRIMARY AND CONDITIONED REINFORCERS

Study focus: Effects of delayed reinforcement on responses of individuals with intellectual disabilities.
Three evaluated conditions:
1. Food reinforcement
2. Token reinforcement with a post-session exchange opportunity
3. Token reinforcement with a post-trial exchange opportunity
Response assessments involved:
- No-reinforcement baseline
- Immediate reinforcement
- Delayed reinforcement with 1 of 6 delays.
Key findings: Delayed food produced greater response persistence than delayed tokens.
Key terms: Conditioned reinforcement, delayed reinforcement, signaled delay, token systems.

Several reinforcement parameters may influence responding:
- Rate
- Magnitude
- Quality
- Delay
Delayed reinforcement focus:
- Basic research on nonhumans examined delayed reinforcement effects on
- Response acquisition (e.g., Lattal & Gleeson, 1990)
- Response maintenance (e.g., Schaal & Branch, 1988)
- Response allocation (Chung & Herrnstein, 1967).
Chung (1965) Study Example:
- Pigeons pecking keys for reinforcement in a concurrent schedule.
- Immediate reinforcement caused systematic response increase; increased delay resulted in decreased responding on the delay key.
- Critical range of delays identified:
- 4s to 8s saw decreasing responses for pigeons.
- Responses dropped significantly beyond 12s delay.

Findings suggest that signaled delays produce greater response persistence than unsignaled delays (Lattal, 1984).
Vollmer et al. (1999):
- Studied signaled versus unsignaled delays in communication responses for individuals with developmental disabilities.
- Results showed that communication response maintenance is better under signaled delays.
Kelley et al. (2011) examined delayed communication response maintenance under signal conditions with varying reinforcers.
Token Systems:
- Involve a second-order schedule of reinforcement.
- Composed of three interconnected components:
1. Token production
2. Exchange production
3. Token exchange
Efficacy of delayed reinforcement and token systems is poorly understood.

Assess how increasing delay to contingent delivery of a stimulus impacts responding.
Examine differences in response persistence between delayed primary reinforcers and conditioned reinforcers with varied exchange opportunities.

Participants: Three children with intellectual disabilities admitted for severe behavior disorders.
- David: 13 years old, diagnosed with autism and unspecified intellectual disability, communicated using one- to two-word phrases.
- Chris: 7 years old, diagnosed with autism, mood disorder, ADHD, and moderate intellectual disability, limited verbal skills.
- Alex: 8 years old, diagnosed with pervasive developmental disorder, ADHD, and mild intellectual disability, communicated in full sentences.
Experimental sessions conducted in small hospital rooms equipped for monitoring.

Target response aligned with individualized education plans (e.g., color matching, folding towels).
Both primary and conditioned reinforcers constant throughout the experiment.
Tokens used in analyses were back-up reinforcers (e.g., chips).

Data collected during preference assessments and delay analyses.
- Two measurement types:
1. Selection/consumption during preference assessments
2. Responses, consumption, token exchange, and problem behavior during delay analysis.
Interobserver Agreement:
- Assured through specific defined criteria; calculations yield high agreement percentages (e.g., 98-100% for preference assessment).

Prompted trial exposure prior to each session.
Auditory stimulus (buzzer) signals task completion.
Sessions terminated based on:
1. 30 reinforcers earned
2. 2 min without responding
3. Participant indicates finished (Alex only).

Food Analysis:
- No-reinforcement, immediate reinforcement (0-s delay), delayed reinforcement phases.
Token Analysis:
- Similar structure to food analysis but with tokens.
Exchange Analysis:
- Differences in exchange opportunities after immediate or delayed token delivery.

David's Performance Patterns:
- Responded well during no-reinforcement baseline, achieving maximum responses in immediate reinforcement.
- Significant response decreases noted with longer delays, particularly 120s leading to a 92% decrease from immediate reinforcement.
Chris's Response Behavior:
- Exhibited variable responding; 66% decrease noted after 3s delay in token analysis.
Alex's Results:
- Persisted in responses until encountering 120s delay, where 71% decrease occurred.

Illustrative figures detail response rates and patterns across conditions.
Table 1 summarizes delay values assessed for each subject in different analyses.
Table 2 reflects mean obtained delay values and related figures across analyzed conditions.

Overall, all subjects' responding decreased with increased delay to reinforcement, with delayed food generally producing highest persistence.
Notable response variability during immediate reinforcement return in token analysis suggests further complexities in token effectiveness during delayed scenarios.
Self-generated behavioral strategies (e.g., counting) observed in Alex may indicate adaptive behaviors promoting improved delay tolerance.

Session limits capped, and exchange opportunities not fixed, possibly impacting clarity of responding.
Delay sessions presented in ascending order that may have influenced subjects' responses.
Future research should consider varied reinforcer exchanges and delays to ensure broader applicability of findings.

Include comprehensive citations relevant to key findings and theories alluded to in the study.