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Resistance to change within heterogeneous response sequences.

Alliston K Reid1

  • 1Department of Psychology, Wofford College, 429 North Church St., Spartanburg, SC 29303, USA. Alliston.Reid@wofford.edu

Journal of Experimental Psychology. Animal Behavior Processes
|July 15, 2009
PubMed
Summary

Pigeons show greater resistance to change (RTC) in initial response positions when instrumental and Pavlovian contingencies are strong. Eliminating instrumental control reverses this pattern, suggesting complex processes influence behavior.

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Area of Science:

  • Behavioral psychology
  • Animal cognition
  • Learning and conditioning

Background:

  • Resistance to change (RTC) is crucial for understanding behavioral flexibility.
  • Previous research has primarily focused on homogeneous response sequences.
  • The role of ordinal response position in heterogeneous sequences remains underexplored.

Purpose of the Study:

  • To investigate how instrumental and Pavlovian contingencies influence RTC in different ordinal positions within heterogeneous response sequences.
  • To compare RTC in initial and terminal positions under varying contingency strengths.
  • To test the explanatory power of current theoretical models.

Main Methods:

  • Three experiments using pigeons and a three-response sequence with colored key lights.
  • Manipulation of instrumental and Pavlovian contingencies (strong, degraded, eliminated).
  • Assessment of RTC at initial, middle, and terminal response positions.

Main Results:

  • When instrumental contingencies were present, initial response positions showed greater RTC than terminal positions, regardless of Pavlovian contingency strength.
  • When instrumental contingencies were eliminated, RTC patterns reversed, showing a graded pattern (Initial < Middle < Terminal).
  • Current theories failed to explain these findings.

Conclusions:

  • Ordinal position significantly affects RTC in heterogeneous sequences.
  • Behavioral momentum theory, conditioned reinforcement, and motivational control theories do not fully account for the observed RTC patterns.
  • A gradient model may better explain RTC by incorporating dissociable processes.