Comparison of reinforcement and punishment functions produced by the same contingent event in the same subjects

The same event, forced running, was used to reinforce the lever-pressing of six rats in one component of a multiple schedule and to punish their drinking in another component. When the durations of running were converted to probabilities that Ss would not be running at t + n sec, given that the run gegan at t = 0 sec, both reinforcement and punishment were found to be linear (inverse) functions of the probability of not-running. A high concordance (0.90) between slopes of the reinforcement and punishment functions indicated that individual Ss were either sensitive to both reinforcement and punishment or sensitive to neither.     

Perceptual asymmetries in face recognition

Four experiments were carried out to investigate perceptual asymmetries in face recognition. Perceptual asymmetries favoring the half-face on the observer's left were found under free viewing conditions for both unfamiliar faces (Experiment 1) and famous faces (Experiment 3). For unfamiliar faces, this asymmetry was not obtained when fixation was controlled by presenting faces tachistoscopically (Experiment 2). For famous faces, the perceptual asymmetry favoring the half-face normally seen on the left did not appear to be retained in memory (Experiments 3 and 4). Asymmetries in face perception have been explained in terms of a direct access model of laterally effects. However, these results raise the possibility that asymmetric scanning or attentional factors may be important.     

Analysis of memory codes and cumulative rehearsal in observational learning

The present study examined the influence of memory codes varying in meaningfulness and retrievability and cumulative rehearsal on retention of observationally learned responses over increasing temporal intervals. Symbolic codes combining meaningfulness with retrievability produced superior memory performances, but responses were poorly retained in symbolic representations containing only one of these properties. Individual response analysis further confirmed that the more meaningful the codes incorporating retrieval guides the better are modeled responses learned and retained. Cumulative rehearsal had differential effects on memory performances depending upon the serial input position of the responses and the form into which the modeled behavior was encoded. Code rehearsals facilitated retention of early and intermediate responses which were repeated more than later ones, but this was true mainly for codes vulnerable to loss. The overall findings provide further corroborative evidence that memory performances are governed more by information coding than by associative strengthening processes.     

Developmental trends in the use of perceptual and conceptual attributes in grouping,clustering, and retrieval

In Experiment I, two tasks were administered to children aged 4, 5, and 9 in order to investigate preference for perceptual versus conceptual attributes in grouping of common objects, and in various aspects of memory. The grouping task revealed a clear chronological progression: color and form determined the youngest children's grouping about equally; form dominated in the 5-year-olds; and most of the oldest children grouped primarily by conceptual attributes. In the memory task, three lists—one organized by color, one by form, one by superordinate category—were presented for free, followed by cued recall. Clustering showed the developmental shift from color to form to concept, while cued recall showed conceptual superiority at all ages. Experiment II replicated the memory task, yielding the same results. The results were discussed in terms of the relative abstractness and predictability of conceptual versus perceptual attributes and the difficulty of abstraction in encoding and the function of predictability in retrieval.     

The gestures of a gorilla: language acquisition in another pongid

A female lowland gorilla, Koko, has been engaged in an ongoing language program since July 1972 when she was 1 year old. During the first 30 months of training she acquired a vocabulary of 100 words in American Sign Language which she spontaneously combined into meaningful and often novel statements of up to 11 signs in length. The gorilla is using a rapidly expanding vocabulary of signs to express semantic and possibly grammatical relations similar to those expressed by human children in the early stages of language acquisition. Patterns of generalization, gradual increase in mean length of utterance, and innovative use of gestural language are discussed in relation to data available on children and chimpanzees.     

Storage and retrieval processes in sentence memory

Two experiments investigated how much time Ss take to verify a sentence with respect to a set of subject-verb-object (SVO) propositions they had learned. Three triplets of SVOs provided differing degrees of equivocation, including (1) unique SVOs, (2) a V with 3 SOs, and (3) an SV with 3 Os. A general class of models was proposed regarding the representation of prepositional trees in memory and an algorithm by which a probe tree might be verified against a set of trees in memory. In Expt I, verification times were least for Condition (1), slower and equal for Conditions (2) and (3). In Expt II, a fourth condition, an SO with 3 Vs, produced verification times as slow as those in Condition (3). Of several models considered, the closest-fitting one assumed parallel search processes proceeding simultaneously from S, V, and O positions of the probe, scanning through memory trees structered according to the HAM (Human Associative Memory) theory of Anderson and Bower.     

The complexity continuum in the radex and hierarchical models of intelligence

The hierarchical and radex models of ability organization are shown to be parallel. Both models suggest a complexity continuum along which cognitive performance tasks can be arrayed. In our revised radex model, the complexity continuum from the center to the periphery is shown to correspond to the general-to-specific dimension in factor analyses, or to test correlations with the general factor; complexity is redefined as apparent processing complexity. Examination of the theoretical and empirical bases for this continuum indicates its central importance for theories of intelligence.     

Role of referent concreteness in the acquisition of passive sentence comprehension through abstract modeling

The present experiment tested the hypothesis that development of syntactic comprehension through verbal modeling is enhanced by referent concreteness as a contextual influence. Young children heard a model narrate a series of events in passive form while the model either performed the corresponding activities, showed pictures portraying the same activities, or displayed no referential aids. In accord with prediction, verbal modeling with enactive referents produced higher levels of comprehension of passives than modeling with pictorial referents or modeling without referential aids. Modeling with pictorial referents and modeling without referents did not differ in overall efficacy. However, modeling alone produced results that were less consistent across different measures of comprehension. Children who lacked understanding of passives were more dependent on concrete referents than those who had some initial comprehension of the linguistic form. The results suggest that verbal modeling with pictorial referents and verbal modeling alone facilitate comprehension of passives, whereas verbal modeling with enactive referents promotes learning. Findings of a supplemental experiment reveal that the effects of verbal modeling on comprehension are enhanced when syntactic forms occur in a meaningful verbal context.     

The influence of symbolic and motor rehearsal in observational learning

The experiment investigated the effects of the mode and patterning of rehearsal on the acquisition and retention of modeled activities varying in organizational complexity. Subjects observed a filmed model construct two configurations, containing high or low organizational requirements. Immediately after exposure they rehearsed the modeled activities either mentally, motorically, mentally and then motorically, motorically and then mentally, or engaged in a distracting activity that prevented rehearsal of what they had see. Performance tests were conducted immediately after the rehearsal phase and again 1 week later. Subjects who rehearsed the modeled behaviors symbolically, whether singly or in conjunction with motor practice, reproduced both configurations more accurately than those who rehearsed motorically or not at all. Motor rehearsal increased speed on the organizationally simple task, but did not enhance response acquisition over and above observation alone. The overall results are interpreted as supporting the social learning view that modeled behaviors are best acquired when demonstrated activities are first organized symbolically and then refined on the basis of performance feedback.     

Methodological issues in the study of sex-related differences

Ten ubiquitous methodological problems are described in relation to group differences research and particularly sex-related research. Substantive issues in sex-related research are used as illustrations of the methodological problems.     

Beliefs,personality, and person perception: A theory of individual differences

The hypothesis tested was that we attend to aspects of our interpersonal environment that correspond to prominent features of our own personality. One hundred fifty-four men and women rated the way in which they typically communicate and interact with significant other people (e.g., mother, father, lover) on 11 bipolar adjective scales and the way in which those other people interact with them. An individual differences multidimensional scaling analysis of interstimulus distances among the significant other people based on the ratings of the subject's interaction with those other people indicated that subjects who weighted a particular dimension tended to think they possessed a personality trait corresponding to the dimension. Reasons for the individual difference hypothesis were given.     

A procedural theory of eye movements in doing arithmetic

A procedural theory of eye movement that accounts for main features of the stochastic behavior of eye-fixation durations and direction of movement of saccades in the process of solving arithmetic exercises of addition and subtraction is presented. The best-fitting distribution of fixation durations with a relatively simple theoretical justification consists of a mixture of an exponential distribution and the convolution of two exponential distributions. The eye movements themselves were found to approximate a random walk that fits rather closely in both adult and juvenile subjects the motion postulated by the normative algorithm ordinarily taught in schools. Certain structural features of addition and subtraction exercises, such as the number of columns, the presence or absence of a carry or a borrow, are well known to affect their difficulty. In this study, regressions on such structural variables were found to account for only a relatively small part of the variation in eye-fixation durations.     

Classes and collections: Internal organization and resulting holistic properties

This work presents an analysis of a type of concept, the collection, not readily characterized by class inclusion models. Collections, the referents of collective nouns (e.g., pile, family, bunch), are argued to differ from classes in (a) how membership can be determined, (b) part-whole relationships, (c) internal structure, and (d) the nature of the higher order units they form. From this analysis, it is hypothesized that the psychological integrity of collections is greater than that of classes. Collections and objects, in contrast to classes, both require specified relationships among the parts and both result in a coherent psychological unit. It was suggested that objects form a relatively more stable unit than collections. Corresponding to this analysis the degree of psychological integrity is hypothesized to lead to different degrees of difficulty in making part-whole comparisons for objects, collections, and classes in modified Piagetian class-inclusion paradigms. The hypothesized difference in performance was found for collections and classes and an alternative linguistic explanation for the greater success with collections was eliminated. However, children performed equally well on tasks involving collections and objects, raising the possibility that when elements are organized into collections, they form psychological units which are as coherent as objects.     

Constraints on the visual accuracy of drawings produced by young children

Errors made by young children when they are asked to draw a model were investigated in two studies. In the first study, the experimenter asked 5- and 8-year-old children to draw a cup that had a flower decal (transfer) attached to its outside surface, attached to its inside surface or positioned beside it. The 8-year-old children in all conditions produced visually accurate drawings. The 5-year-old children produced visually accurate drawings when the flower decal was positioned beside the cup and when the flower decal was attached to the inside surface of the cup but not when the flower decal was attached to the cup's outside surface. In the second study, 5- and 8-year-old children were asked to draw a cup that had either an intact or a broken handle. The handle area of the cup was either in view or not in view. The 5- and 8-year-old children performed comparably in this experiment. The children had difficulty producing accurate copies of the model only when the cup had a handle and the handle was not in view. Taken together, these studies indicate that 5-year-old children are more likely to produce visually accurate drawings than has previously been supposed. Difficulty in producing accurate drawings occurred when drawing rules and drawing conventions interfered with the task.     

A note on real measurement structures of scale type (m,m + 1)

Real relational structures of scale type (1, 2) can be represented in the reals in such a way that the induced automorphism group is properly contained in the affine group and itself properly contains the group of translations. There are no real relational structures of scale type (m, m + 1), m ≥ 2.     

The layman's use of trait and behavioral information to predict behavior

This study investigated conditions that determine subjects' preferences for information about another person's traits versus his specific past behavior in order to predict his future behavior. The similarity-dissimilarity between the situation for which past behavior was available and the one to which predictions had to be made strongly influenced the choice of specific behavioral information versus more general trait information. As expected, behavioral information was preferred most when the situation to which behavior had to be predicted was highly similar to the one for which the past behavioral data were available. On the other hand, more general trait information was preferred in predicting to situations that were not directly similar to those for which past behavioral information was available. The effect of the temporal span covered by available information was also explored.     

Distortions in memory for maps

Evidence is presented for systematic errors in memory for real and artificial maps, local environments, and visual forms. These errors are attributed to two heuristics that are derived from principles of perceptual organization. Maps of countries or localities are conceived of as figures in backgrounds. Remembering the absolute location of figures is difficult, and is facilitated by remembering locations relative to other figures and/or relative to the natural directions of the figure. In alignment, figures are lined up relative to one another, a phenomenon related to perceptual grouping by proximity. In rotation, the natural axes induced by a figure converge with frame axes (north-south, east-west, or horizontal, vertical), a phenomenon related to perceptual organization by common fate. Heuristic-induced errors occur in a variety of tasks, and even when subjects are explicitly forewarned. These heuristics may be invoked in forming representations as well as in inference, and function analogously to syntax in locating smaller elements in larger units.