Color logic of apparent motion

Two shapes of either the same or different color will seem to be in smooth apparent motion with like-colored mates, at proper conditions of flash timing and spacing. An experiment is reported in which the condition was tested for unlike-colored pairs, for example red-green alternated with green-red. The question of interest was how the visual system would resolve the disparity of color. An 'intelligent' solution would rotate the shapes in three dimensions. Like-colored and unlike-colored parts were found to move and transform similarly, however, the resolution being dependent more upon timing than upon color. The motion of intelligence as it might be applied to vision is discussed in light of these results.     

Orientation of letters and errors in their recognition

Subjects named alphabetic characters that had been rotated, reflected, or inverted. Inversions induce more errors than mirror reflections and reflections induce more than rotations. In a significant number of mistakes a transformed character was assumed to be normally oriented, but in most a transformed character was confused with the mirror image of the original. The data suggest the existence of an “orientation set” in which the identiflcation of ambiguous characters depends largely on their anticipated orientation. The individuality of the data for the different orientations suggests that different transformations are compensated for in part by different mechanisms.     

Graphemic analysis underlying literacy

Three experiments are described that studied the role of detailed graphemic analysis upon the ability to read text. College students named letters in various approximations to English, with frequency of individual letters constant. Findings were that later skill at reading varied with the order of approximation to English of the letters that were named, that the spacing of the letter sequences was important to this result, and, finally, that the influence of specific visual practice extended to the typeface on which the naming and reading were carried out. Hence, rather than a letter-by-letter process or its opposite, a wholly semantic analysis, reading is shown to be intimately dependent upon details of visual analysis of patterns or letter sequences.     

Specificity of operations in sentence recognition

When we read a sentence do we abstract out its semantic core and discard the surface representation, or is the surface representation an integral part of the encoded sentence? This question was studied by measurement of transfer to a second reading of a sentence of skill acquired in a first encounter with the sentence. The transfer relation was studied when the typography, language, or modality of the first and second embodiments were varied. The results favor a theory that emphasizes recognition in terms of the pattern analyzing operations that are directed at surface lexical representations. A distinction is brought out between operational or procedural memory and substantive or semantic memory. In many cases memory of procedures may be sufficient to recover the information encoded. Stage-wise processing theories do not seem to have place for such notions.     

Spatial and ordinal components of form perception and literacy

We suppose that the visual nervous system possesses compensatory rectifying mechanisms by means of which it achieves “constancy” of visual recognition despite variation in physical appearance of the stimulus object. Using geometric rotations, reflections, and other transformations of text as the physical variation, we studied the recognizability of the texts and the influence that practice in reading one type of transformation exerted on the recognition of others. The mathematical structure of the training set was used as a clue to the perceptual mechanisms mediating transfer, isolating perceptual functions involving a geometric transformation and an ordinal operator. The main feature of the theory is its emphasis upon a dialogue or interaction between ongoing problem-solving processes in visual rectification and the sample being recognized. The theory developed is contrasted with other theories of pattern recognition in which concepts such as stimulus generalization, tuned detectors, and preprocessing play major roles. A relation of this theory to problems encountered among disabled readers (“dyslexics”) is also brought out.     

Knowing not

Ontario Institute for Studies in Education, 252 Bloor Street, Toronto, Ontario, Canada M5S 1V6 People often know rapidly and reliably that they do not know something. A review of contemporary theory reveals that the issue has not received much attention; moreover, the accounts available assume that recognition that one does not know something is achieved only by failure to establish that one does know it. A reaction time experiment assessed two aspects of knowing not, by asking people whether they knew common nouns well enough to use them in sentences and whether they had visited certain cities. The findings were that affirmations of negation were often more rapid than positive reports; hence, the account of knowing not as the complement of knowing that something is the case is not necessarily correct. We suggest that knowing not may be attained as rapidly as positive knowledge on the basis of ability to carry out analytical procedures.     

Rhythms and responses

Rhythms are fundamental to behavior, but the control mechanism for timed responses is not known. Many theorists have assumed that there is a central clock coordinating behavior in all sensory modalities and response modes. We tested this hypothesis using a rhythmic tapping task in which university undergraduates first attempted to synchronize responses with brief auditory, tactile, or visual stimuli and then continued to tap at the same rate on their own. Performance was most variable with visual stimuli and least variable with auditory stimuli. The detailed results suggest that performances are not based on a common clock, but, rather, different strategies are employed when the task is presented in different modalities. We reject the hypothesis of a single timing mechanism as controlling behavior and, in doing so, question the validity of information processing models that are formulated without regard to temporal relations among their conjectured processes.     

Floating Provisos and Sinking Islands

Rising sea levels may sink entire countries. Individualistic solutions to this climate catastrophe, such as those proposed by Meisels and Risse, are inadequate on both Kantian and Lockean criteria. This article concurs with Cara Nine's recent argument that such ‘ecological refugee states’ are entitled to territorial remedies. But Nine's proposal, founded on Locke's ‘sufficiency’ proviso and Nozick's famous application of it to waterholes in the desert, is instructively incorrect. Careful consideration of the distinction between land and territory, and of the structure of Proviso arguments, supports a new theory of how territorial claims can be positive‐sum — how the amount of territory can increase even as the land base remains constant or decreases. This normative conception of territory as the ratio of justice to land use provides a better foundation for a political solution to the problem of ecological refugee states and also generates deeper insight into the nature of territory itself. The article thus contributes not only to our thinking about redress for ecological refugees, but also to the burgeoning literatures on territory and on the Lockean Provisos.