FixedRatio1

Fixed Ratio 1 (FR1)

The Fixed Ratio (FR) schedule was first described in Schedules of Reinforcement by Ferster and Skinner (1957) as a reliable method for studying the relationship between response output and reinforcement. In an FR task, an animal must complete a fixed number of operant responses (e.g., a nosepoke) to obtain each reward, with the ratio remaining constant across opportunities. In a FED-based closed economy design, the device is continuously available in the home cage, and animals earn food exclusively through task performance rather than through discrete daily sessions. This arrangement eliminates the need for food restriction and allows long-timescale measurement of operant behavior in a naturalistic environment.

Code

/*
  Feeding experimentation device 3 (FED3)
  Fixed Ratio 1
  alexxai@wustl.edu
  December, 2020

  This project is released under the terms of the Creative Commons - Attribution - ShareAlike 3.0 license:
  human readable: https://creativecommons.org/licenses/by-sa/3.0/
  legal wording: https://creativecommons.org/licenses/by-sa/3.0/legalcode
  Copyright (c) 2020 Lex Kravitz
*/

#include <FED3.h>                                       //Include the FED3 library 
String sketch = "FR1";                                  //Unique identifier text for each sketch
FED3 fed3 (sketch);                                     //Start the FED3 object

void setup() {
  fed3.begin();                                         //Setup the FED3 hardware
}

void loop() {
  fed3.run();                                           //Call fed.run at least once per loop
  if (fed3.Left) {                                      //If left poke is triggered
    fed3.logLeftPoke();                                 //Log left poke
    fed3.ConditionedStimulus();                         //Deliver conditioned stimulus (tone and lights for 200ms)
    fed3.Feed();                                        //Deliver pellet
  }

  if (fed3.Right) {                                     //If right poke is triggered
    fed3.logRightPoke();                                //Log right poke
  }
}

References

Ferster, C. B., & Skinner, B. F. (1957). Schedules of Reinforcement. Appleton-Century-Crofts.

Aberman, J. E., Ward, S. J., & Salamone, J. D. (1998). Effects of dopamine antagonists on feeding and operant behavior: Behavioral specificity, arousal, and anhedonia. Psychopharmacology, 138(1), 51–60.