Trace conditioning as a test for animal consciousness: A new approach

Trace conditioning involves the pairing of a neutral conditioned stimulus (CS), followed by a short interval with a motivationally significant unconditioned stimulus (UCS). Recently, trace conditioning has been proposed as a test for animal consciousness due to its correlation in humans with subjective report of the CS–UCS connection. We argue that the distractor task in the Clark and Squire (1998) study on trace conditioning has been overlooked. Attentional inhibition played a crucial role in disrupting trace conditioning and awareness of the CS–UCS contingency in the human participants of that study. These results may be understood within the framework of the Temporal Representation Theory that asserts consciousness serves the function of selecting information into a representation of the present moment. While neither sufficient nor necessary, attentional processes are the primary means to select stimuli for consciousness. Consciousness and attention are both needed by an animal capable of flexible behavioral response. Consciousness keeps track of the current situation; attention amplifies task-relevant stimuli and inhibits irrelevant stimuli. In light of these joint functions, we hypothesize that the failure to trace condition under distraction in an organism known to successfully trace condition otherwise can be one of several tests that indicates animal consciousness. Successful trace conditioning is widespread and by itself does not indicate consciousness.

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Work Title Trace conditioning as a test for animal consciousness: A new approach
Open Access
  1. Paula Droege
  2. Daniel J. Weiss
  3. Natalie Schwob
  4. Victoria Braithwaite
License In Copyright (Rights Reserved)
Work Type Article
  1. Springer Science and Business Media LLC
Publication Date May 13, 2021
Publisher Identifier (DOI)
  1. 10.1007/s10071-021-01522-3
  1. Animal Cognition
Deposited June 15, 2022




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Work History

Version 1

  • Created
  • Added trace conditioning ac revised final-1.docx
  • Added Creator Paula Droege
  • Added Creator Daniel J. Weiss
  • Added Creator Natalie Schwob
  • Added Creator Victoria Braithwaite
  • Published
  • Updated