Related Experiment Video
Updated: Feb 13, 2026

Measuring Delay Discounting in Humans Using an Adjusting Amount Task
Published on: January 9, 2016
The effects of changeover delays on local choice
Stephanie Gomes-Ng1, Jason Landon2, Douglas Elliffe1
1School of Psychology, The University of Auckland, New Zealand.
Abstract:
In concurrent schedules with a changeover delay (COD), choice often strongly favours the just-reinforced alternative immediately after a reinforcer delivery. These 'preference pulses' may be caused by a change in reinforcer availability created by the COD, and/or because the COD decreases the overall probability of switching. We investigated which explanation better accounts for preference pulses by arranging concurrent schedules that allowed us to separate the COD's effects on reinforcer availability from its effects on the probability of switching. When the reinforcer ratio was 1:1, pulses were inconsistently accompanied by changes in reinforcer availability, but consistently accompanied by longer visits. These pulses appeared to be related only to the decreased probability of switching caused by the COD, providing the first evidence of pulses after reinforcers caused by the probability of switching alone. When the reinforcer ratio was 1:5 or 5:1; preference pulses were accompanied by changes in reinforcer availability and by longer visits. These pulses appeared to be related to the COD's effects on reinforcer availability, although a small portion appeared to be related to low probability of switching. These findings suggest that the COD affects preference pulses by both decreasing the probability of switching and creating a change in reinforcer availability.
Related Concept Videos
Local Anesthetics: Adverse Effects
Once absorbed into the systemic circulation, local anesthetics can affect the organs that depend on the functioning of sodium...
Mate Choice
Personal Choice and Fate Attributions
Hypersensitivity Reactions: Delayed Hypersensitivity Reactions
Buffer Effectiveness
The buffer capacity is the amount of acid or base that can be added to a given volume...
Factors Affecting α-Alkylation of Ketones: Choice of Base
The reaction involving bases like EtO− whose conjugate acid EtOH (pKa = 15.9) is stronger than the ketone (pKa = 19.2) results in an equilibrium mixture with higher ketone concentration. As a consequence,...

