Studies of visual synthesis: Integration of fragments into forms

Olfaction: responses of a decapod crustacean are enhanced by flicking

Periodic movements of the olfactory organs, known as "flicking," temporally enhance the response of the olfactory receptors of the spiny lobster to changes in stimulus concentration. This reflex provides the lobster with a physiological mechanism to compensate for the indiscrete temporal nature of chemical stimuli.

Cognitive Regularities in Creative Activity

Theories of creativity have not traditionally considered whether novel ideas or inventive behaviors can result from regularities in the cognitive processes responsible for such activities. Most of these traditional theories are based on the evaluation of products as meeting (or not) some abstract metric of creative output. However, cognitive theories of creativity can be proposed in which creative activity is a function of more traditional cognitive processes that are not unique to inventive behaviors. The purpose of this article is to review the cognitive regularities of creative activity and organize the research on this topic into a framework that might be useful in understanding and extending investigations directed at studying creativity. To these ends, cognitive processes underlying generation, synthesis, and selection of information in creative activities are delineated.

Visual discovery in mind and on paper

The effectiveness of mental imagery with and without drawing support (perceptual assistance) in the visual synthesis of novel patterns was studied in three experiments. When the task was to create one recognizable pattern from three simple shapes in a 2-min assembly period, subjects were as likely to produce a recognizable or creative pattern per trial whether mental imagery was augmented by external drawing support or not. When the task was to create as many patterns as possible in a 3-min assembly period, more patterns were produced per trial with external drawing support than without; however, neither the recognizability nor the creativity of the patterns differed. Differences in performance in the visual synthesis task with and without external drawing support are interpreted in terms of limited cognitive resources.

Is a perceived shape based on its retinal image?

Although the processing of phenomenal shape might be supposed to begin at an early stage, with the shape of the retinal image of an object, it is possible that it does not begin until a later stage at which the locations of the parts of the object have been perceived. Such perceived locations are based on a compensation or constancy mechanism that takes account of eye position. Ordinarily these two possible bases of shape perception--retinal image and perceived location--are confounded. To separate them the parts of a shape were presented sequentially, during which time the eyes were in motion. The eye movement did not alter phenomenal locations of the parts vis-à-vis one another but did yield an entirely different composite retinal image of the parts. Another method employed was to change the location of each sequentially presented part with respect to a displacing frame of reference. By and large the results indicate that the composite shape perceived is based on the perceived location of the parts of the object with respect to one another, rather than on the composite retinal image.

Manipulation of visual mental images in children and adults

Recently, there has been a debate on whether visual patterns can be transformed and reinterpreted in mental imagery. In the present study, task demands and age of subjects were manipulated to see whether children and adults were able to discover a novel visual pattern after transforming a mental image. Two tasks, called combination and subtraction, were devised. They consist of either compounding or taking away parts of images to discover a new construal. Results indicate that not only adults, but also children aged 6 and 10, are able to transform a mental image so as to yield another image with a different interpretation. Task demands had a greater effect on children than adults, consistent with the suggestion that the ease of manipulating mental images is a function of the efficiency of control processes.

Length distortion of temporally extended visual displays: similarity to haptic spatial perception

Three experiments were designed to investigate length distortion--the tendency to inflate estimates of the inferred distance between two points, as the length of a circuitous pathway between them increases. This phenomenon, previously demonstrated with haptic and locomotor exploration (Lederman, Klatzky, Collins, & Wardell, 1987), was extended to vision through the presentation of pathways as a temporal sequence of illuminated points. The magnitude of the visual effect was less than that previously found in haptics, and conditions promoting the effect included a relatively slow presentation rate and moderately complex pathways. Commonalities in the pattern, if not the magnitude, of length distortion in vision and haptics suggest that similar processes of spatial encoding may underlie the phenomenon in both domains.