Research Commons
      • Browse 
        • Communities & Collections
        • Titles
        • Authors
        • By Issue Date
        • Subjects
        • Types
        • Series
      • Help 
        • About
        • Collection Policy
        • OA Mandate Guidelines
        • Guidelines FAQ
        • Contact Us
      • My Account 
        • Sign In
        • Register
      View Item 
      •   Research Commons
      • University of Waikato Theses
      • Masters Degree Theses
      • View Item
      •   Research Commons
      • University of Waikato Theses
      • Masters Degree Theses
      • View Item
      JavaScript is disabled for your browser. Some features of this site may not work without it.

      Peak Shift in Remembering

      Hoan, Andros
      Thumbnail
      Files
      thesis.pdf
      1.651Mb
      Citation
      Export citation
      Hoan, A. (2003). Peak Shift in Remembering (Thesis, Master of Arts (MA)). The University of Waikato, Hamilton, New Zealand. Retrieved from https://hdl.handle.net/10289/2487
      Permanent Research Commons link: https://hdl.handle.net/10289/2487
      Abstract
      If remembering is discriminative behaviour along the dimension of time and if, as Sargisson and White (2001) argued, generalisation around a peak can occur in this behaviour, then the peak shift which has been shown in discrimination along so many other stimulus dimensions, might also occur in remembering. To examine this hypothesis, 6 hens were trained in a delayed matching-to-sample procedure at delays of 2 and 4 s. The probability of reinforcement for correct responses was initially 0.9 at both delays until performance stabilised. A generalisation probe was then carried out by inserting unreinforced trials at delays of 0, 1, 1.5, 2.5, 3, 3.5, 4.5, 5 and 6 s in a session amongst normal training delay trials. The generalisation functions had a slight peak around 2 s. After further training, a second generalisation probe showed a slightly declining function. The probability of reinforcement at the 2 s delay was then dropped to 0.1, so that in the terms of the classical generalisation/peak shift paradigm, 2-s delay trials became S- and 4-s delay trials became S+. A third generalisation probe then was conducted. This resulted in a flat function from 0 s to 3 s, and a large, clear peak in discriminative performance at 4.5 s over all hens. After more of the same differential reinforcement training, a fourth generalisation probe showed a broad curve peaking at 3 s, with minima at 1 s and 6 s and a global maximum at 0 s. Another training condition was then run, with the probability of reinforcement at the 2-s delay dropped to 0, to see if increasing the "aversiveness" of S- would again result in a peak shift. A fifth generalisation probe was then conducted. This showed a sharp decline in discriminability at shorter delays, a dip around 2 s, and a very small area shift beyond 4 s, but no clear peak shift. This was interpreted as being due to overlearning, with the consequences of remembering at S- no longer significantly affecting performance at S+. A final training condition was then run, with S- moved from 2 s to 3 s with zero probability of reinforcement, and for only a short period, to prevent overlearning. It was predicted that this would cause peak shift to re-occur. A sixth generalisation probe was then conducted. This found a further decline in discriminability at shorter delays, a shift in the dip from 2 s to 3 s, and a large, clear peak at 4.5 s. This demonstration of peak shift in a remembering process would not have been predicted by any traditional theory of memory, but strongly supports the conception of remembering as discriminative behaviour along the stimulus dimension of time.
      Date
      2003
      Type
      Thesis
      Degree Name
      Master of Arts (MA)
      Publisher
      The University of Waikato
      Rights
      All items in Research Commons are provided for private study and research purposes and are protected by copyright with all rights reserved unless otherwise indicated.
      Collections
      • Masters Degree Theses [2385]
      Show full item record  

      Usage

      Downloads, last 12 months
      41
       
       

      Usage Statistics

      For this itemFor all of Research Commons

      The University of Waikato - Te Whare Wānanga o WaikatoFeedback and RequestsCopyright and Legal Statement