Infant responses to approaching objects: An indicator of response to distal variables

Infants show an adaptive avoidance response to approaching objects. The response is affected by the closeness and speed of approach. It is mediated by visual variables. Air-pressure changes do not elicit the response. This kind of response implies discrimination and response to distal variables rather than merely to their proximal mediators.     

Inconsistency in spatial knowledge

Two experiments examined whether spatial information judged from cognitive maps contains the functional euclidean properties of real maps. In Experiment 1, the six directions between sets of threetriad locations in a town were judged from memory. The angle formed by the two judged directions from a location to the other two locations in a triad was derived. The three derived angles of a triad were then summed. The derived angles were found to be biased toward 90 deg. The sum of the three derived angles of a triad also exceeded 180 deg, which violates the euclidean properties of real maps. In Experiment 2, subjects judged the direction between pairs of American cities in both directions. The judged directions were found to be consistently nonreversible, which is contrary to the properties of euclidean geometry. The study suggests that information judged from cognitive maps can contain internally inconsistent spatial properties, and the results are discussed in terms of current theories of spatial representation.     

Intersensory substitution in the blind

This study looks at the implications for theories of development of an intersensory surrogate for the blind—the Sonicguide. Results of both short- and longterm studies suggest that there is a critical age, before which use of the Sonicguide is qualitatively more effective than attempts at intervention begun after this age. Similarly the young infants in the sample show a much more rapid acquisition of ability to use the guide effectively. The importance of such results for theories of perceptual development is discussed.     

Comparisons of models of associative recall

We tested three mathematical models of associative recall that differ in the assumed structure of the memory trace (direct or indirect connections between parts) and the interdependence of the connections (independent or correlated). The three models compared are the “horizontal” model with direct, independent connections, the “schema” model with indirect, independent connections, and the “fragment” model with indirect, correlated connections. In Experiment 1, subjects studied quartets of minimally related words and then recalled, using one or two words of each quartet as cues. The horizontal and schema models predicted the data very well, but the fragment model did poorly. In Experiment 2, related word quintets were learned, and recall cues contained one, two, or three words of a quintet. Only the schema model adequately fit these data. Experiment 3 directly tested the fragment model, using sequential tests of unrelated word quartets. Even an augmented fragment model with extra recall failure parameters was decisively rejected by these data. Both the horizontal and schema models gave satisfactory qualitative accounts, although poor quantitative fits. A means of deriving the models through a spreading activation semantic network of preexperimental knowledge is suggested, and related models are discussed.     

The “soap opera” effect in story recall

When people learn a series of actions of a character, their memory is strongly influenced, we suggest, by beliefs about that character’s motives. Motives serve as schema for deciding the meaning of the actions, their importance, and their interconnections. In two experiments, subjects read and later remembered some dull activities of a character. Experimental subjects knew what this character was worrying about (e.g., an unwanted pregnancy); control subjects did not. Recall and recognition showed that motive subjects distorted many of the colorless events to be motive relevant. Although the motive schema helped connect the disparate actions, it interfered with accurate recording and recall of the details.     

Remembering information related to one's self

How does memory for an incident vary depending on whether, and how, the person relates the information to himself? Trait adjectives are better remembered if they were judged in reference to oneself rather than judged for meaning or sound. Our first experiment found a similar mnemonic advantage of referring a described episode or object to some event from one's life. Pleasant events were remembered better than unpleasant ones. A second experiment found incidental memory for trait adjectives was equally enhanced by judging each directly in reference to one's self-concept or indirectly by retrieving an episode either from one's life or from one's mother's life. Contrariwise, memory was poorer when traits were judged in reference to a less familiar person. Thus, good memory depends on relating the inputs to a well-differentiated memory structure.     

Phenomenal identity and form perception in an infant

Gestalt psychologists described in some detail the stimulus conditions which determine which parts of an array will be seen as units possessing “phenomenal identity.” These same stimulus conditions, often called the Gestalt laws, were held to be effective determinants of form perception too. A previous study indicated that only one of the Gestalt laws, common fate, was an effective determinant of phenomenal identity in human infants of less than 16 weeks of age. The present study using a more powerful technique shows that another of the Gestalt laws, good continuation, is an effective determinant of phenomenal identity and form perception in infants of 36 days of age. A third variable, proximity, is not effective in this age range.     

Transfer across drives of the discriminative effect of a Pavlovian conditioned stimulus

Previous results suggest that a stimulus paired in Pavlovian fashion with reward should exert some discriminative control over an unrelated operant response acquired under a different drive-reward system. In the following experiment, a stimulus was first paired with food reinforcement for a hungry rat. Subsequently, the animal learned to lever-press for water reinforcements when thirsty but not hungry. Finally, the control over lever-pressing of the food-paired stimulus was tested by presenting it at various times during extinction of the lever-pressing response. All animals in the experiment showed the expected effect; each emitted more lever-presses during periods of the food-paired stimulus than during alternate control periods.