Cookies Policy

This site uses cookies. By continuing to browse the site you are agreeing to our use of cookies.

I accept this policy

Find out more here

A Criterion Setting Theory Of Discrimination Learning That Accounts For Anisotropies And Context Effects

Brill’s MyBook program is exclusively available on BrillOnline Books and Journals. Students and scholars affiliated with an institution that has purchased a Brill E-Book on the BrillOnline platform automatically have access to the MyBook option for the title(s) acquired by the Library. Brill MyBook is a print-on-demand paperback copy which is sold at a favorably uniform low price.

Access this chapter

+ Tax (if applicable)

Chapter Summary


Weber's Law states that the differential threshold or just-noticeable-difference (jnd) is proportional to the physical intensity of the stimulus. Fechner built up his logarithmic law of sensation intensity from Weber's Law and the assumption that all jnds are subjectively equal. The Parallel Law states that, when perceived stimulus intensity is changed by something other than physical intensity (such as adaptation), Weber's Law continues to hold: discrimination should be unchanged provided the perceived values of the two stimuli change in the same ratio. Discrimination between stimuli is usually finest when the adaptation level is appropriate to the test level. There is insufficient evidence concerning the discrimination of tactile length and visual length when perceived length is changed. However, the Parallel Law may be untestable because of the difficulty of obtaining measures in the same experiment both for changes in discrimination and for the ratios of the perceived changes of the stimuli.

Keywords:adaptation; discrimination; Parallel Law; perceived length; tactile length; visual length; Weber Law


This chapter proposes a theory of the integration of sensory information across modalities. This is based on criterion setting theory, an extension of signal detection theory which models the setting and adjustment of decision criteria. The theory of sensory integration based on CST (CST-SI) offers an account of cross-modal effects on sensory decision-making. The chapter considers its application to orientation anisotropy. Predictions from CST-SI are tested by experimentally separating the contributions that different information sources make to stabilize the visual criteria. It is shown that reducing relevant kinaesthetic input may increase the variance for discrimination of the visual cardinal axes but not the obliques. In addition, peripheral visual stimuli were shown to affect the discrimination of cardinal but not oblique orientations at the focus of vision. These results support the present account of anisotropies.

Keywords:criterion setting theory; kinaesthesia; orientation anisotropy; sensory integration (CST-SI)




Can't access your account?
  • Tools

  • Add to Favorites
  • Printable version
  • Email this page
  • Recommend to your library

    You must fill out fields marked with: *

    Librarian details
    Your details
    Why are you recommending this title?
    Select reason:
    Fechner's Legacy in Psychology — Recommend this title to your library
  • Export citations
  • Key

  • Full access
  • Open Access
  • Partial/No accessInformation