Kanizsa's shrinkage illusion produced by a misapplied 3-D corrective mechanism

In order to include the monocular areas from the left and the right eye in the cyclopean view, the visual system displaces the occluded elements which would result in a horizontal elongation of the shape but does not occur thanks to a correction mechanism which preserves the shape. We hypothesised that this mechanism causes Kanizsa's amodal shrinkage illusion (the apparent elongation of a partially occluded square) when it is incorrectly applied by the visual system to a two-dimensional stimulus. Four experiments tested this hypothesis: (i) one-eyed observers were less susceptible to the illusion than people with normal binocular vision because, for them, the correction for shape is unnecessary; (ii) the illusion was stronger with binocular than with monocular vision since binocularity induces the visual system to correct for the shape distortion; (iii) the illusion diminished when the stimulus was rotated 90 degrees given that displacement and compression are not required for vertical occlusion; (iv) the magnitude of the illusion was a function of the width of the occluder because, as previous research has shown, the edges of a partially occluded square are less displaced the farther they are from the edges of the occluder. The data from the four experiments support our hypothesis even though no condition was able to eliminate the illusion; other possible causes are discussed.     

When remembering causes forgetting: retrieval-induced forgetting as recovery failure

Retrieval practice on a subset of previously learned material can cause forgetting of the unpracticed material and make it inaccessible to consciousness. Such inaccessibility may arise because the material is no longer sampled from the set of to-be-recalled items, or, though sampled, its representation is not complete enough to be recovered into consciousness. In 2 experiments, it was examined whether retrieval-induced forgetting reflects a sampling or recovery failure by studying the time course of cued recall in this type of situation. Although retrieval practice reduced recall totals of the unpracticed items, in both experiments, the forgetting was not accompanied by an effect on the items' response latencies. This pattern of results is consistent with the view that inhibited items are successfully sampled but, because of a reduction in their activation level, do not exceed the recovery threshold.     

Is emotional content obtained from parafoveal words during reading? An eye movement analysis

An eye-movement-contingent display change technique was employed to study whether adult readers extract semantic information from parafoveal words during reading. Three types of parafoveal preview conditions were contrasted: an emotional word, a neutral word, and an identical word condition. To have a maximally effective parafoveal manipulation, high-arousal emotional words (sex- and threat-related and curse words) were used as parafoveal previews. Readers' eye fixation patterns around the target word revealed no evidence for parafoveal semantic processing. Furthermore, the pupil size showed no signs for an emotional response triggered by an emotional word previewed parafoveally. These results are consistent with the view that, as a rule, only the fixated word is processed to a semantic level during reading.     

Crossfostering in mice selectively bred for high and low levels of open-field thigmotaxis

The main purpose of this research was to investigate whether the difference in open-field (OF) thigmotaxis between mice selectively bred for high and low levels of wall-seeking behavior originated from genetic or acquired sources. Unfostered, infostered, and crossfostered mice were compared in two experiments in which the effects of strain, sex, and fostering on ambulation, defecation, exploration, grooming, latency to move, radial latency, rearing, thigmotaxis, and urination were studied. These experiments revealed that OF thigmotaxis was unaffected by the foster condition and thus genetically determined. The selected strains of mice also diverged repeatedly with regard to exploration and rearing. The findings are in line with the previously described existence of an inverse relationship between emotionality and exploration.     

Ambiguous pronoun resolution: contrasting the first-mention and subject-preference accounts

A visual-world eye-tracking experiment investigated the influence of order of mention and grammatical role on resolution of ambiguous pronouns in Finnish. According to the first-mention account, general cognitive structure-building processes make the first-mentioned noun phrase the preferred antecedent of an ambiguous pronoun. According to the subject-preference account, the preferred antecedent is the grammatical subject of the preceding clause or sentence. Participants listened to sentences in either subject-verb-object or object-verb-subject order; each was followed by a sentence containing an ambiguous pronoun that referred to either the subject or the object. Participants' eye movements were monitored while they looked at pictures representing the two possible antecedents of each pronoun. Analyses of the fixations on the pictures showed that listeners used both order-of-mention and grammatical-role information to resolve ambiguous pronouns.     

Big-five personality differences of cheaters and non-cheaters

Infidelity is a major factor in causing marital dissolution and dissatisfaction in North America. Similarities in personality traits influence the desire for a monogamous relationship commitment. The present study examined differences between cheaters and non-cheaters on Goldberg’s (1990) “Big-Five Personality Factors”: Extroversion, Agreeableness, Conscientiousness, Emotional Stability, and Intellect-Openness. One hundred and four participants volunteered to answer a questionnaire on personality traits about themselves and their monogamous partners. A total of 45 males and 59 females rated themselves and an equal number of partners on the traits (n = 208). Results revealed statistically significant differences between cheaters and non-cheaters on the five-factor model. Differences were also found between both of the group’s perceptions of themselves and their monogamous partners on these factors. We wish to thank the editor and reviewers of this journal for their helpful and precise comments towards revisions of this publication. The primary author also wishes to thank Dr. Kevin Alderson for his suggestions on earlier drafts of this paper.     

Fitting one matrix to another under choice of a central dilation and a rigid motion

A least squares method is presented for fitting a given matrixA to another given matrixB under choice of an unknown rotation, an unknown translation, and an unknown central dilation. The procedure may be useful to investigators who wish to compare results obtained with nonmetric scaling techniques across samples or who wish to compare such results with those obtained by conventional factor analytic techniques on the same sample.Part of this work was done while the senior author held a visiting research fellowship at the Educational Testing Service, Princeton, New Jersey.     

Varisim: A new machine method for orthogonal rotation

The derivative of Kaiser's Varimax criterion, if set to zero, yields a set of equations which are quite similar to those obtained for a least-squares problem of the Procrustes type. This similarity suggested an iterative technique for orthogonal rotation, dubbed Varisim, which was programmed for the IBM 7094 in FORTRAN. An empirical comparison between Varimax and Varisim, which was based on a number of data sets taken from the literature yielded three major results so far: (i) Varisim is slower than Varimax, roughly by a factor of 3, (ii) Varisim yields factors which in general contribute more evenly to the common test variance than Varimax factors, and which (iii) line up more closely with oblique configurations obtained with Binormamin than Varimax factors.This paper is based on parts of a thesis submitted to the Graduate College of the University of Illinois in partial fulfillment of the requirements for a degree in Psychology. Some of its contents were read at the joint meeting of the Psychonomic and the Psychometric Society, Niagara Falls, Ontario, 1964. Most of the computer-bound work was carried out while the author was employed by the Statistical Service Unit, University of Illinois; it was written up while the author held a Postdoctoral Fellowship at the Psychometric Laboratory of the University of North Carolina. Although space limitations forbid more complete acknowledgments, I am bound to record my deep gratitude to my advisor, Prof. H. F. Kaiser.