Similarity comparisons with remembered and perceived magnitudes: Memory psychophysics and fundamental measurement

Abstract

At the outset, subjects learned to associate a label with each element in a set of perceptual magnitudes (visual extents), using traditional paired-associate learning methods, Subsequently, on some trials, subjects indicated which pair of two pairs of labels corresponded to the more similar perceptual referents, and, on other trials, they selected the more dissimilar pair. It is shown that these similarity comparisons satisfy the axioms (transitivity and intradimensional subtractivity) necessary to conclude that they are based on computation of the difference of the differences of analogue-based interval scale representations.The findings also permitted refutation of the idea that memory for elementary percepts arises from their reperception. Notably,the memory exponent was 0.697, but the perception exponent was 0,546, and the reperception idea requires that the memory exponent be the square of the perception exponent (0.546 2 = 0.298). Symbolic distance effects and enhanced response time-based semantic congruity effects, typicallyfound with binary comparisons, extend the range of commonalties found between perceptual and memory psychophysics.Memory psychophysics extends Fechner's (1860/1966) outer psychophysics to a determination of the quantitative relationship between the physical magnitude of a stimulus and its subjective magnitude-not as it is perceived but, rather, as it is remembered. In this article, we explore the properties of the representation oflong-term memory for elementary visual percepts and the representation of the percept itself, and we examine their interrelationships in detail. We begin with a brief review of the principal findings based on the application of classical psychophysical techniques to remembered stimuli, and we discuss some of the limitations of that work. We then address the fundamental question of whether a memorial This research was supported by a grant from the Natural Sciences and Engineering Research Council of Canada to W.M.P. Portions of this work were presented at the XXV International Congress of Psychology, Brussels, July, 1992 . The experiment was conducted by R.K. as part of her master's degree requirements at the Department of Psycho 1-ogy, Carleton University. Our thanks to Geoffrey Loftus, Gregory Lockhead, and two anonymous reviewers for their helpful comments. Correspondence should be addressed to W. M. Petrusic, Department of Psychology, Carleton University, Colonel By Drive, Ottawa, Ontario, K1S 5B6, Canada (e-mail: biILpetrusic@carleton.ca).-Accepted by previous editor, Geoffrey R. Loftus representation of a basic element of sensory experience can be maintained in memory at the level of an interval scale, by extending the axiomatic approach offundamental measurement (Krantz, Luce, Suppes, & Tversky, 1971) to the domain of memory psychophysics by requiring comparative judgments ofsimilarity/dissimilarity. Specifically, the subjects were presented with two pairs of pairs (quads) and were required, on some trials, to indicate which pair was more similar and, o...

The representation of numerical magnitude

“…Conversely, they were much faster at choosing the larger of two large values compared with the smaller of two large values. Thus, the semantic congruity effect cannot be a byproduct of a language-specific comparative process but is instead, more generally, a hallmark of the psychological process for comparing analog representations of magnitude [24,25].…”

Semantic congruity affects numerical judgments similarly in monkeys and humans

“…than ''Which is smaller?'' This effect is known as the semantic congruity effect and has been reported for adult humans when they compare stimuli along a variety of continua, including the distance between two cities (13), line length (14), brightness (15), the intelligence of animals (16), adjectives of ordinal quality (e.g., good, fair, poor, or excellent; ref. 17), surface area (18), and Arabic numerals (19,20).…”

“…These models assume that the semantic congruity effect arises when humans represent the elements of a given problem as discrete mental symbols that are analogous to words. In contrast, other models have emphasized the role of nonsymbolic, analog mental codes in comparative processes (14,20). These models assume that the semantic congruity effect arises when the elements of a problem are compared along a continuous distribution rather than as discrete symbols.…”

Context affects the numerical semantic congruity effect in rhesus monkeys (Macaca mulatta)

“…When asked to compare two large items, adults are quicker to respond to the question “Which is larger?” than “Which is smaller?” Conversely, when asked to compare two small items, adults are quicker to respond to the question “Which is smaller?” than “Which is larger?” The semantic congruity effect has been demonstrated with a variety of stimuli, including animal sizes, distance between cities, line length, brightness, surface area, Arabic numerals, and the numerosity of dot arrays (Cech & Shoben, 1985; Cech, et al, 1990; Holyoak & Mah, 1982; Petrusic, et al, 1998; Audley & Wallis, 1964; Moyer & Bayer, 1976; Banks, et al 1976; Holyoak, 1978). For example, when evaluating Arabic numerals, adults indicate that 2 is smaller than 3 more quickly than they indicate that 3 is larger than 2.…”