Premium
PREFERENCE FOR LESS FREQUENT SHOCK UNDER FIXED‐INTERVAL SCHEDULES OF ELECTRIC‐SHOCK PRESENTATION
Author(s) -
Pitts Raymond C.,
Malagodi E. F.
Publication year - 1991
Publication title -
journal of the experimental analysis of behavior
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.75
H-Index - 61
eISSN - 1938-3711
pISSN - 0022-5002
DOI - 10.1901/jeab.1991.56-21
Subject(s) - interval (graph theory) , electric shock , shock (circulatory) , preference , presentation (obstetrics) , computer science , psychology , statistics , mathematics , medicine , combinatorics , electrical engineering , engineering , surgery
Lever pressing by 2 squirrel monkeys was maintained under fixed‐interval 6‐min and fixed‐interval 2‐min schedules of electric‐shock presentation. Preference for these schedules was assessed during three experimental phases. In all phases, responses on one lever produced shock according to one or the other fixed‐interval schedule, and responses on a second, changeover, lever switched between schedules. The opportunity to change over was presented during separate choice periods (during which the fixed‐interval schedules did not operate) that followed the first through fourth shocks in each schedule. If no changeover occurred during those choice periods, a changeover automatically occurred following the fifth shock. In Phase I, durations of the choice periods were fixed. In Phase II, the choice periods equaled a proportion of their respective fixed interval. During Phase III (completed with 1 monkey) a response on the changeover lever during a given choice period reinstated the most recent fixed interval, and a failure to respond resulted in a changeover. During each of these phases, distinct preferences developed for the 6‐min schedule. These results suggest that the maintenance of lever pressing by fixed‐interval presentation of electric shock may not be an example of positive reinforcement, and that the response‐maintaining characteristics of shock presentation may derive from other properties of the schedule.