Comment on “Effect of Overtraining on Subsequent Learning of Incidental CUES”

Abstract

Church (3) has recently reported a set of experiments designed to test the conditions under which animals, while making discriminations on the basis of one set of cues, will pick up information about newly introduced incidental cues that later may be used to guide discriminative choice when the original cues are removed from the situation. Like Blum and Blum (1) and Bruner, Matter, and Papanek (2), he found that rats do indeed learn something about such incidental cues while operating on previously established cue-discrimination habits. The heart of the issue about which I wish to comment briefly has to do with a hypothesis introduced by Bruner, Matter, and Papanek (2 ) and tested by Church (3 ). It is that if the animal is highly overtrained in his response to the original cue to which he is responding and is highly motivated, there will be less likelihood of his picking up the incidental cue when it is introduced into the situation. By highly motivated, we can mean the 36-hr. food deprivation used by Bruner, et nl. or the 22-hr. water deprivation used by Church. Overlearning of a cue is a matter of 200 to 300 trials of practice with the original cue before introduction of the incidental cue which can also be used to guide behavior in the situation. The general hypothesis proposed by Bruner, et nl. was that when behavior becomes mechanized with overlearning, the organism ceases to elaborate cue-goal cognitive maps or expectancies. Church in his ingenious experiments introduces an interesting and worthwhile distinction concerning incidental cues of the type under discussion. The distinction is between new cues that are introduced and previously irrelevant cues that are made relevant at a given point in the progress of overlearning. Bruner, et ul. used the latter procedure, Church the former. In the first of these experiments, rats were responding to black or white doors in a four unit T-maze, with position of the doors randomized. After a certain amount of overlearning, the correct doors were always arranged in an LRLR or RLRL sequence and. finally, the color cue was removed and animals tested for their mastery of single alternation. In short, a previously irrelevant cue suddenly became relevant and we ask under what conditions the animals '.notice3' that the cue has become relevant. In Church's first experiment, a newr cue was introduced after a period of overlearning. Rats went either to one or I!?? other arm of a single-unit T-maze, depending on whether a black or n hit? card cue was present on the side. The incidental cue added after over