Structural alterations of an ambiguous musical figure: The scale illusion revisited

The scale illusion (Deutsch, 1975) shows the importance of frequency range in the perceptual organization of a sequence of notes. This paper includes three experiments on the scale illusion. Experiments 1 and 2 demonstrated that if the structure of the pattern of notes used in the original scale illusion study is altered slightly, by adding or subtracting a pair of notes from the ends of the sequence, there is a significant decrease in the rate of frequency-based responses, suggesting a weaker illusion. Experiment 3 investigated two features of the note patterns that may have led to this change. Specifically, it asked whether the decrease in the strength of the illusion is due to (1) the nature of the notes at the extremes of the frequency range and/or (2) the nature of the notes at the crossing point of the two scales. While both sources were found to affect the strength of the scale illusion, the former had a greater influence.     

Structural alterations of an ambiguous musical figure: the scale illusion revisited.

The scale illusion (Deutsch, 1975) shows the importance of frequency range in the perceptual organization of a sequence of notes. This paper includes three experiments on the scale illusion. Experiments 1 and 2 demonstrated that if the structure of the pattern of notes used in the original scale illusion study is altered slightly, by adding or subtracting a pair of notes from the ends of the sequence, there is a significant decrease in the rate of frequency-based responses, suggesting a weaker illusion. Experiment 3 investigated two features of the note patterns that may have led to this change. Specifically, it asked whether the decrease in the strength of the illusion is due to (1) the nature of the notes at the extremes of the frequency range and/or (2) the nature of the notes at the crossing point of the two scales. While both sources were found to affect the strength of the scale illusion, the former had a greater influence.     

The letter-frequency effect and the generality of familiarity effects on perception

A widely accepted perceptual principle is that familiar patterns are easier to recognize than are less familiar patterns. Previous letter-recognition studies are examined to determine whethermore frequent letters in English are easier to recognize than less frequent letters (the letterfrequency effect). Most studies required subjects to identify single letters, while some measured reaction time to compare two letters or name or classify a letter. The results, based on over 800, 000 observations from 58 studies that span nearly 100 years, showed that: (1) there is no letter-frequency effect in recognition studies in which subjects simply report letters, and (2) there is a letter-frequency effect in reaction time studies. The presence of la letter-frequency effect for reaction time studies is interpreted as demonstrating an effect of familiarity on a comparison stage and perhaps a response stage, but not on input coding. The absence of a letter-frequency effect for single-letter recognition studies is interpreted as limiting the generality of the effect of familiarity on perception and as limiting the generality of models that correctly predict frequency effects for words. Alternative explanations for the absence of a letter-frequency effect are discussed.     

The effect of an imagery training program on imagery ability,imagery use,and figure skating performance

Abstract

There is a growing popularity of non-pharmacologic treatments for hypertension; among them is exercise. This paper critically reviews the evidence for the anti-hypertensive effect of exercise, scanning both the epidemiologic and experimental research. It evaluates some of the literature on exercise adherence, briefly describes one exercise program designed to promote adherence, and draws conclusions based on the literature.     

The influence of age, sex, and specialized training on the vertical-horizontal illusion

With the aim of investigating the perceptual processes responsible for perceptual illusions, we have studied the influence of age, sex and specialized training on two forms of the vertical-horizontal illusion. In Figure A, the vertical is a short distance away from the horizontal; in Figure B, the vertical meets the horizontal segment at its mid-point. Both figures were presented in brief (0-2 second) and long (I-o second) tachistoscopic exposure, and in unlimited exposure.

When time is unlimited. Illusion A increases up to 9-10 years and then remains constant and Illusion B decreases as a function of age and chiefly as a function of the degree of scientific training. The illusions are stronger in tachistoscopic perception than under conditions of umlimited exposure. Both illusions also increase in tachistoscopic perception with age except for science students. Under condition of unlimited time, women have stronger illusions than men. This difference does not occur in tachistoscopic perception.

These results may be interpreted in terms of the interaction of three processes: interaction among the elements of a figure (field effects); perceptual activity which makes possible the passing from syncretism or multiplicity to organized perception; and the activity of measuring the elements relatively to each other. This latter activity develops with cultural level and especially with scientific training. It is more effective with men than with women, due, it is suggested, to the spatial factor being higher in men.     

Comparing effects of the horizontal-vertical illusion on grip scaling and judgment: relative versus absolute, not perception versus action

The discovery that the prehension component of an open-loop, two-fingered reach is largely immune to certain salient pictorial illusions has been used to suggest that humans possess 2 distinct visual systems, 1 that subserves perceptual judgment and 1 that mediates visually controlled action. In this article, the authors present evidence that suggests that the critical distinction is not that of reaching and judgment but of relative and absolute perception. Experiment 1 extends the findings of S. Aglioti, J. F. X. DeSouza, and M. A. Goodale (1995) and suggests that the manual prehension component of open-loop reaching is affected by the horizontal-vertical illusion to a much smaller degree than perceptual size judgments. In Experiments 2 and 3, however, when perceptual size judgment is directed at a single element of the display, this difference vanishes. Experiment 4 demonstrates that grip scaling is strongly affected by the illusion when a single reach is scaled to both the horizontal and vertical components of a triangular figure.     

Problem solving by reference to rules or previous episodes: The effects of organized training,analogical models,and subsequent complexity of experience

Subjects learned a microcomputer drawing package under different conditions of training organization and practice complexity. Training instructions were presented in either a random or an organized order, and with or without an analogical model of the software package. Practice trials varied in visual and logical complexity. Performance on paper-arid-pencil and problem-solving tests was better following the model than following the no-model condition when practice trials were logically complex; the reverse was true when they were logically simple. Performance on the test of problem solving was also better following organized training than following randomly ordered training when practice trials were visually complex; the reverse was true following visually simple practice. We propose that the subjects performed the tasks by engaging in either episodebased or rule-based processing, and that performance was optimized when the processing used at encoding and retrieval was the same. The acquisition of skill in solving real problems is explained as procedural compilation.     

The effects of various rater training procedures on the perception of social skills and social anxiety

Procedures for the behavioral assessment of social skills typically rely on judges' perceptions of subjects' behavior in several simulated situations. This study examined two methodological variables which could influence the degree of situational specificity perceived by social skill judges. Forth-eight judges were presented videotapes of 15 actors who role played responses to eight simulated social situations. Half of the judges viewed the situations in a sequential fashion and the remaining half viewed the tapes grouped by situations. The second factor of this design included three different expectancy conditions included in an analogue training procedure. Differences in observed variability were examined for both social skill and social anxiety constructs. Order of stimulus presentation had no effect on variability. The expectancy manipulation significantly increased variability among social skill ratings but had no effect on reliability.This study was supported in part by the Veterans Administration.     

The Leaning Tower of Pisa effect: an illusion mediated by colour, brightness, and motion

We report a novel, easily observed, and extraordinarily striking optical illusion mediated by interactions of colour, brightness, form, and motion perception--the Leaning Tower of Pisa (LTOP) illusion. Under some circumstances, the perception of orientation of coloured forms is radically altered by rotary movement. We demonstrate that this kinetic effect--easily reproduced with a common record turntable--is optimised by particular colour and brightness differences between foreground and background with an illusory tilt of 8 degrees and more. The described illusions can be easily studied at home by downloading the colour figures from www.perceptionweb.com/perc1000/ditzinger, printing them on a common colour printer and placing them on a rotating record turntable.     

Speech, "inner speech," and the development of short-term memory: effects of picture labeling on recall

Three experiments explored the effect of overt speech on children's use of "inner speech' in short-term memory (STM). Experiments 1 and 2 compared recall of a series of pictured objects when 5- and 11-year-olds either labeled stimuli at presentation or remained silent. Use of inner speech was assessed by manipulating word length of the picture names (Experiment 1) or phonemic similarity (Experiment 2). Word length and phonemic similarity had greater effects in the older children and when pictures were labeled at presentation. These tendencies were such that 5-year-olds were sensitive to word length and phonemic similarity only with labeling. Experiment 3 compared labeling by the child with labeling by the experimenter in 5-year-olds. There were no significant differences with respect to overall performance or effects of word length and phonemic similarity. It is suggested that speaking or listening to speech activates and internal "articulatory loop,' and that such activation is especially important when the child's ability to use inner speech in STM has not fully developed.     

The effects of figure/ground, perceived area, and target saliency on the luminosity threshold

Observers adjusted the luminance of a target region until it began to appear self-luminous, or glowing. In Experiment 1, the target was either a face-shaped region (figure) or a non-face-shaped region (ground) of identical area that appeared to be the face's background. In Experiment 2, the target was a square or a trapezoid of identical area that appeared as a tilted rectangle. In Experiment 3, the target was a square surrounded by square, circular, or diamond-shaped elements. Targets that (1) were perceived as figures, (2) were phenomenally small in area, or (3) did not group well with other elements in the array because of shape appeared self-luminous at significantly lower luminance levels. These results indicate that like lightness perception, the luminosity threshold is influenced by perceptual organization and is not based on low-level retinal processes alone.