David Zeaman

An Attention-Retention Theory of Retardate Discrimination Learning1

Publisher Summary This chapter discusses the attention–retention (A–R) theory of retardate discrimination learning. A simplified picture of the overall structure of the theory can be seen in an information-flow, block diagram of the principal events, and transformations to which the theory is addressed. Stimulus information in the discriminative display is conceived in part to be dimensional in nature. The dimensions, such as color, form, position, size, etc., are not defined independently. In the chapter, the theory is discussed together with empirical support in the form of 40 experimental effects deducible from the theory. The two processes of attention and retention are not the only ones postulated to occur; the name A–R theory was chosen because the inclusion of these two processes distinguishes A–R theory from the other models of discrimination. A qualitative outline of the A–R theory is discussed in the chapter, followed by a concise quantitative statement of the theory and an outline of the data domain of the theory. Thirteen sections then follow, each identifying a basic issue, on which theorists of discriminative processes have taken opposing stances.

Miniature Experiments in The Discrimination Learning of Retardates

Publisher Summary The area of discrimination learning can be a surprisingly complex one, with even the simplest classes of discrimination problems solved by relatively unsophisticated subjects. Two-choice visual discriminations by children of low developmental level reveal complexities not suggested by traditional stimulus–response (S–R) theories. Such theories describe the solution of discrimination problems by the formation of single-link associations—the subject learns to approach the positive cue and avoid the negative. But experimental and theoretical analyses of the discrimination learning of trainable retardates have led researchers to the conclusion that more than one associative link is formed. They infer a chain of at least two responses: a response of attending to relevant stimulus dimensions and an instrumental response of approach–avoidance to the cues of the relevant dimension. Some measure of the complexity of this idealized conception of the discriminative process can be had by counting the number of different, theoretically possible outcomes of a simple two-choice experiment.

Growth and Decline of Retardate Intelligence1

Publisher Summary This chapter discusses the growth and decline of retardate intelligence and a study analyzing semi-longitudinally the growth and decline of Binet mental ages of a large institutionalized population of retardates. Traditional intelligence quotient (IQ) theory says that retardate intelligence grows just like normal intelligence, in that mental age grows linearly up to about 16 years of chronological age (CA) and then stops, the only difference being the rate at which it grows. The rate is, of course, the IQ. Higher grade retardates presumably have higher rates of MA growth and lower grades have lower rates. Semi-longitudinal methods have been used to study the growth and decline of retardate intelligence. The basic data were provided by institutional records of Binet mental ages for a population of 1159 resident retardates, varying widely in age and intelligence, each of whom has been tested at least twice over a period of years. The results obtained suggest that the growth of MA of retardates is roughly linear between 5 and 16 years, regardless of the level. Growth rate is directly related to level. Higher level retardates continue to grow in MA for longer periods of their life (at least until the late 1930s). The MA growth functions for lower level subjects flatten off earlier.

Human Heart Rate during Anxiety

When anxiety is induced experimentally by signals of shock-to-come, two opposing effects on human heart rate have been observed. Somecimes the heart decelerates; somecirnes it accelerates. Typical of the deceleration findings is the paper of Notcerman, Schoenfeld, and Bersh (3). With trace conditioning, they found a cardiac slow-down during the 6-sec. interval between warning signal and shock. Representative of the opposice finding is the report by Lacey and Smith (2) of increased hearc race when verbal scimuli previously associaced with shock served as warning signals. Both effects in different Ss have been observed by Zeaman and Wegner (4) following the procedure of Nocterman, Schoenfeld, and Bersh. An actempt was made to give a drive-reduccion explanation of these dual effects by relating them to heart behavior at the time of shock termination. However, a further experimental test by Zeaman and Wegner (5), wich more excreme conditions, failed to support this explanation, As a result, the controlling conditions of these two cardiac effects remain something of a mystery. Ic would aid in understanding the relation of anxiery and heart rate to find both cardiac effeccs in the same Ss under different experimental conditions. Jusc such a finding is described in che present study designed co explore boch cardiac and respiratory activity during anxiety. Ss, warned chac a shock will follow a series of visually-presented numbers, showed a sharp elevation in heart race while looking at the numbers for the first time. Afcer one shock, the accelerative effecc disappeared early in the series, and was replaced later by a decelerative effect.

Role of Positive and Negative Cues in the Discrimination Learning of Mental Defectives

This smdy inquires into the role of the positive and negative cues in the visual discrimination learning of a group of mentally deficient children. If the formation of a simultaneous, two-choice visual discrimination is o chronological age: mean 12, range 9-2 to 17; IQ (Stanford-Binet, 1916 revision): mean 44, range 20 to 64. There were 8 females and 10 males. An unbiased selection was made of the lowest mental age group attending school who were able to meet a performance criterion of successful pattern discrimination within 100 trials. Enumeration of Ss in the various diagnostic categories yielded 5 familial, 1 mongolian, 2 epileptic, and 9 cerebral-palsied or other brain-damaged.

Dimensional shifts and reversals in reterdate discrimination learning

Abstract The facilitative effect of overlearning on discrimination reversal was demonstrated with moderately retarded children. The relevant cues of the reversal were different from, but on the same dimension as, those of overlearning. The superior performance of an intradimensional over an extradimensional shift was also demonstrated, using completely new cues for both shift conditions to control for previous confounding of stimulus novelty in dimensional shift experiments. These results are not accounted for by single-link theories of discrimination learning but do support chaining theories in which the inferred, initial response of the chain is assumed to generalize within but not across stimulus dimensions.

Some relations of general intelligence and selective attention

Abstract General intelligence may set structural feature limitations on three aspects of selective attention: direction, adjustability, and breadth. Amiable hypotheses considered are that subjects of varying intelligence may (1) have some partially fixed tendencies to look at different dimensions of stimuli, (2) have varying rates of adjusting their direction of attention, and (3) have varying upper limits on breadth of attention for tasks demanding it. Data, theory, and methods bearing on these hypotheses were reviewed from the domain of visual discrimination learning.

Theory and data on developmental changes in novelty preference

Abstract As children mature, their preference for novel stimuli changes to a preference for familiar ones in discriminative situations featuring differential reinforcement. This change, observed before, takes place between 4 and 5 years of age. The effect has been replicated in the present study with a population of retarded children, and found to be largely under the control of MA rather than CA. Stimulus factors were also found to exert some influence on this developmental change, with novelty-preference being stronger for objects than pictures. A theoretical model is offered which provides separate assessments of learning and novelty-familiarity preferences in experiments using the Moss-Harlow (1947) design, typically employed in this area. This model is applied to the present data as well as those of previous studies. The results support the conclusion of a developmental change in novelty-familiarity preference between MA 4 and 5 years.

Contiguity and imbeddedness factors in the discriminative learning of retardates

Abstract Previous studies show that imbedding a reward within a stimulus and spatial contiguity of stimulus and reward are factors which facilitate 2-choice discriminations. In the present study, the separate and joint effects of the two factors on discriminative learning are studied in a factorial design. Reward imbeddedness was manipulated by presenting the reward within a hollow box and was compared with a nonimbeddedness situation in which the reward was placed in a foodwell under the box. Contiguity was arranged by presenting copies of the discriminative stimulus in the goal situation (either the box or the foodwell) and was compared with noncontiguity in which the reward alone was presented in the goal situation Contiguity facilitates learning but imbeddedness does not reliably improve learning. The two factors interact significantly and in a direction which is consistent with previous findings.

Effects on retroaction of the learned strength of interpolated material

Abstract Twelve moderately retarded children were trained on 2-choice visual discrimination problems with interpolation of another item between training and retention tests. The retroactively interfering property of the interpolated items was reduced as it became well-learned. The effect was interpreted to mean that well-learned items are rehearsed less. The results were found to be consistent with predictions from theory.