Loss of control by a less valid or by a less salient stimulus compounded with a better predictor of reinforcement

An unsalient stimulus, or one imperfectly correlated with reinforcement, may acquire significant control over responding, provided that it is the only available signal for reinforcement, but may fail to acquire control if it is reinforced only in conjunction with a second, more salient or more valid stimulus. A stimulus imperfectly correlated with reinforcement may also lose control over responding if having initially been reinforced in isolation, it is subsequently reinforced only in conjunction with another, more valid stimulus. If the effects of relative salience are to be explained in exactly the same way as those of relative validity, we should expect a similar loss of control by an unsalient stimulus, A, if, after initial consistently reinforced trials to A alone, subjects subsequently receive reinforcement only in the presence of a compound stimulus, A + B. Two experiments on discrete-trial discrimination learning in pigeons and one on conditioned suppression in rats confirm this expectation. The results have implications for theories of selective association in conditioning and discrimination learning.     

Encoding and incidental memory in children

First, third, and fifth graders (7.1, 8.8, 11.1 years old) performed semantic, acoustic, and orthographic orienting activities to different words in a list. Without forewarning, their free recall of the words was tested after the orienting activity. The semantic task yielded better recall than the acoustic or orthographic tasks, but the latter two did not differ. Age differences in recall were absent, and the effect of the three orienting tasks did not vary as a function of the child's age. The results support a direct extension of levels of processing theory (Craik, F. I. M., & Lockhart, R. S. Journal of Verbal Learning and Verbal Behavior, 1972, 11, 671–684) to children's memory. An obligatory-optional encoding distinction was suggested as a developmentally relevant addition to the levels of processing framework.     

Differences in encoding for free recall vs. recognition

Three experiments examined effects of test expectancy on memory for relatively unrelated words. In Experiment I, where preliminary recall or recognition practice was given, both recall and recognition were superior when the subjects expected and had practiced for recall. Free study led to better recall and recognition than paced presentation, but did not interact with test expectancy. Experiment II demonstrated that recall was better for subjects expecting a recall vs. a recognition test in the absence of preliminary practice. In Experiment III all subjects practiced both recall and recognition prior to presentation of the critical list. Study time also was varied. With longer study, recall was better when a recall test was expected, with no test expectancy effect on recognition. There were no appreciable expectancy effects with the short study period. Self-reports and other data suggested that the critical encoding differences produced by test expectancy manipulation were quantitative in nature.     

Elementary school retention: An unjustifiable, discriminatory and noxious educational policy

The long and short term correlates of first and second grade retention are examined in relation to the variables of achievement and intelligence over a six year period. The retained and promoted control group were also compared in terms of relevant demographic variables: sex, race, initial intelligence, socioeconomic level of family, father absent, etc. The data led the authors to conclude that retention is an unjustifiable, discriminatory, and noxious educational policy.     

The role of the CS and its relationship to the CR in avoidance conditioning

Two studies are reported which are concerned with the role of the CS and its relationship to the CR in the standard avoidance learning situation. Study I demonstrates that the decrement associated with a trace CS is greatly reduced in one-way avoidance as compared with two-way. The suggestion is made that the differences in CS effects is attributable to differences in task complexity. Study 2 varied CS duration and the CS-CR termination contingency. Rapid acquisition of the avoidance response was obtained only when the CS remained on for the entire CS-US interval unless terminated by a response. The results were discussed with respect to the theoretical aspects of maintenance and emergence of the avoidance response.     

Effects of teacher attention on attending behavior of two boys at adjacent desks

The effects of teacher attention on the attending behavior of two boys seated at adjacent desks were investigated. Baseline records were obtained of the appropriate attending behavior of two boys who were described as the most disruptive pupils in a second-grade classroom of a poverty area school. During the first experimental phase, the teacher systematically increased the amount of attention for appropriate attending in one of the pair, Edwin. This resulted in a dramatic increase in his attending rate and a lesser, though significant, increase in attending behavior of the second boy, Greg. During the second experimental phase, systematic attention for attending was instituted for Greg and was discontinued for Edwin. This resulted in further increases in attending by Greg and a reduction in attending by Edwin. A brief withdrawal of reinforcement for attending in both Greg and Edwin reduced attending levels for both. Following this reversal appropriate attending for both boys was systematically reinforced and attending returned to high levels.     

Opacity,coreference, and pronouns

The problem discussed here is to find a basis for a uniform treatment of the relation between pronouns and their antecedents, taking into account both linguists' and philosophers' approaches. The two main candidates would appear to be the linguists' notion of coreference and the philosophers' notion of pronouns as variables. The notion of coreference can be extended to many but not all cases where the antecedent is non-referential. The pronouns-as-variables approach appears to come closer to full generality, but there are some examples of pronouns of laziness which appear to resist either of the two approaches.Earlier versions of this paper, under various titles, were presented orally to the Claremont Philosophical Discussion Group, the UCLA Linguistics Colloquium, the IBM Watson Research Center, the IBM Systems Development Division at Endicott, and at Princeton University. Criticisms and suggestions received on these occasions have helped lead to many revisions and additions. I am particularly grateful for the sympathetic encouragement given me by philosophers such as David Kaplan, Jack Vickers, and Gilbert Harman in this attempt to communicate simultaneously with linguists and philosophers.The most important sources for the present work are the following: among linguists, Postal (1968), for bringing the notion of coreference to prominence; Bach (1969, 1970), for first pointing out some fundamental problems with the treatment of pronominalization as a substitution process; McCawley [1967 (forthcoming), 1968], for his attempts to show logical notation, including the use of variables, to be of linguistic relevance; and Karttunen (1968a, b, 1968a, b), who has been exploring many of the same problems as are discussed here, and from whom a number of the examples below are taken or adapted (some of which are originally due to Baker (1966)). Among philosophers, the main sources are Quine (1960), for the notion of opacity and its relation to reference; Donnellan (1966), for claiming a referential/attributive distinction in definite noun phrases even in transparent contexts; and Geach (1962) for distinguishing pronouns of laziness from pronouns used like variables.