Perception
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In two experiments subjects were asked to report the identity of a position-cued critical letter in an array of four letters. Four types of arrays were used: (i) unpronounceable nonwords; (ii) pronounceable nonwords ('pseudowords'); (iii) words in which the critical letter was minimally constrained by the context letters; and (iv) words in which the critical letter was maximally constrained by the context letters. All four-letter stimuli were presented in two parts. ⋯ Performance in the word conditions was consistently superior to performance in the nonword conditions, and the magnitude of this difference (ie, the word-superiority effect) increased with increasing stimulus onset asynchrony up to 120 ms, and then gradually declined. The fact that the magnitude of the word-superiority effect initially increased with the separation of leading and trailing arrays was interpreted as support for Johnston's suggestion that letters in words are represented during visual encoding both in the form of individual letter percepts and in a decay-resistant word percept, as opposed to letters in nonwords, which are represented only as decay-susceptible letter percepts. The experimental findings are discussed in relation to the 'interactive activation' model of word perception.
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One hundred and five college students made estimates of the lengths of freely swinging pendulums mounted in an apparatus that masked all but the top few inches of the pendulum string. The law of pendulum motion shows that visible aspects of pendulum motion uniquely specify the length of the pendulum. ⋯ In three studies estimates were found to be linear functions of actual lengths, though with wide differences in slopes among individual observers. These results, together with statements made during post-experimental interviews, are interpreted as showing that observers use a rule to the effect that length is a linear function of 'speed', where speed appears to be a function of both period and angular velocity.
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Following Piaget and Inhelder's work, considerable evidence has accrued showing that young children have difficulty constructing the horizontal and vertical in particular drawing tasks. However, one recent study by Ibbotson and Bryant interpreted these difficulties as lying with angle reproduction rather than representation of horizontal and vertical. Their conclusion was that children of 3 to 5 years distort acute angles to look more like right angles. ⋯ One puzzling result emerged. The bisection effect only appeared with oblique-baseline figures. The tentative interpretation is that, when the baseline is horizontal or vertical, children can easily note that nonbisected figures are asymmetrical about vertical or horizontal axes, and hence resist the tendency to distort representations towards symmetry.
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A twelve-letter array was segmented into figure and ground by moving some of its letters. Moved letters were shifted one letter-width left of right, independently of each other, in apparent movement. Since the figure of a display attracts attention, identification of letters of the figure segment should show an advantage over letters of the background segment. ⋯ This result suggests that the segment seen as figure is determined by both rapidly encodable letter movement and by the number of moved letters within the display. Second, segmentation of the visual display acids identification of moved letters in less than 90 ms, or well before the eye can move to the selected letter position. Third, letters in the figure segment which are closer to fixation are more likely to be identified than more eccentric letters.