Adaptation in distance perception based on oculomotor cues

Accommodation and convergence primarily serve to adjust the eyes to the distance of the object viewed, but, once made, these oculomotor adjustments serve as cues for the object’s distance. Experiments are reported that show that the relation between oculomotor adjustments and the distances they signify can be changed by adaptation to glasses that cause alteration in the oculomotor adjustments with which objects are viewed. This changed relation manifested itself in marked alterations of size perception. Wearing, for 30 min, glasses that caused a change in accommodation and convergence corresponding to a smaller object distance and equivalent to 1.5 lens diopters caused subsequent mean size increases that ranged from 50% to 65%. Adaptation to glasses that changed oculomotor adjustments in the same amount but in the opposite direction resulted in decreases in perceived sizes that varied from 18% to 40%, dependent on the distance of the test object. These were the results of size estimates obtained before and after the adaptation period under conditions where only accommodation and convergence served as cues for distance. A newly developed test of size perception was also used, in which S adjusted the size of the projected image of an array of familiar objects on a screen until the size of the objects appeared normal. Again, such adjustments were made before and after the adaptation period, and size differences were obtained that were in the direction to be expected of adaptation and varied in amount between 12% and 33%, dependent on the distance of the screen. The reason for the different amounts of size change measured by the two kinds of tests was investigated.     

Effects of inferiority and superiority in groups on recognition memory and confidence

Summary Three dependent variables were derived from an extended Signal-Detection paradigm: memory performance, confidence level, and response-bias. In the assessment of memory items, S and 2 confederates were exposed periodically to fictitious results which implied inferiority or superiority of S. Memory performance was generally better in group situations than when the subject was alone. Within groups, inferiority motivated S to improve. Significant confidence differences between correct and false judgments and, if S judged falsely, a high susceptibility to cognitions about S's relative performance, led theoretically to a distinction between internal and external cues and to the assumption that S wished to avoid uncertainty. Response-bias was found to be independent of motivation and very close to expected stimulus occurrence. The reward/cost theory of Thibaut and Kelley accounts for the motivation engendered and is linked to some theoretical considerations about processing objectively classifiable stimuli in social context.

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Zusammenfassung Aus einem erweiterten Signal-Detection-Paradigma wurden 3 abhängige Variablen abgeleitet: Gedächtnisleistung, Sicherheitsniveau und Response-bias. Bei der Beurteilung von Gedächtnisaufgaben wurden einer Vp und 2 Mitwissern des Vl von Zeit zu Zeit fiktive Ergebnisse gezeigt, die entweder Unterlegenheit oder Überlegenheit der Vp induzierten. Verglichen mit einer Alleinsituation stieg die Gedächtnisleistung allgemein in Gruppensituationen. Innerhalb von Gruppensituationen wurde die Vp durch Unterlegenheit motiviert, sich zu verbessern. Signifikante Unterschiede in der Sicherheit zwischen richtigen und falschen Urteilen und hohe Beeinflußbarkeit durch Kognitionen über den relativen Leistungsstand der Vp bei Fehlerurteilen führte theoretisch zu einer Unterscheidung zwischen innerem und äußerem Aufschluß und zu der Annahme, daß die Vp Unsicherheit vermeiden will. Der gefundene Response-bias war unabhängig von Motivation und sehr nahe bei der Wahrscheinlichkeit des Auftretens der Reize. Die reward/cost Theorie von Thibaut und Kelley kann die erzeugte Motivation erklären und wird mit einigen theoretischen Überlegungen über die Verarbeitung objektiv definierbarer Reize im sozialen Kontext verknüpft.

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This research was supported by research grants from the Deutsche Forschungsgemeinschaft allotted to the Sonderforschungsbereich 24 at the University of Mannheim, West Germany. We are grateful to Mary Madden, Pauline Sadler, and Jennifer S. Sentance for their cooperation on the English translation.

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This article is partly based on a Diplom-thesis by the second author entitled Effekte von Überlegenheit und Unterlegenheit in Gruppen auf Gedächtnisleistung und Skalengebrauch.     

Negation of Park's transformations

Zusammenfassung Parks Kritik beruht, meiner Ansicht nach, auf einem entscheidenden Mißverständnis meiner Intentionen: es geht mir überhaupt nicht um eine Argumentation gegen eine Transformationsgrammatik à la Chomsky, und nicht einmal in erster Linie gegen die Absicht mancher Psycholinguisten, eine derartige Theorie in ihren psychischen Funktionen aufzuzeigen. Ich möchte lediglich dafür plädieren, daß die Psycholinguistik in erster Linie psychologische (und nicht linguistische) Überlegungen und Modellvorstellungen als Leitlinien verwendet.     

Adaptation in the constancy of visual direction measured by a one-trial method

Adaptation to field displacement during head movements in the direction with the head rotation and in the direction against it was produced under otherwise identical conditions and compared; the field displacement rate was also varied. A rapid training procedure was used, and a novel one-trial test was employed that could measure the adaptation well enough to compare the effects of various training conditions. The one-trial test measured the magnitude of one of the manifestations of adaptation, the apparent displacement of a stationary target during head movements. This apparent horizontal target displacement was transformed into an oblique one by having the head movements that brought forth the apparent target displacement simultaneously cause an objective vertical target displacement. The slant of the resultant apparent motion path varied with the magnitude of the apparent horizontal target displacement. It was measured by having S reproduce its slant angle. It was found that adaptation to field displacement in the direction with the head rotation was consistently greater than adaptation to the opposite displacement conditions. An explanation for this result is offered.     

The effect of abnormal displacement of the retinal image during eye movements

The displacement of the images on the retina that results from a turning of the eye does not lead to an apparent motion of what is seen, It has been generally assumed that this is due to a compensating process which takes eye movement into account and serves to discount those image displacements that result from eye movements, It follows from this view that an abnormal image displacement, that is, an image displacement that is larger or smaller than the causing eye movement would warrant, should lead to an experienced displacement of the target. Abnormal image displacement was produced by placing the eye in the converging or diverging bundle of rays from a point source that form behind a strong positive lens; this arrangement yielded a disc-shaped image, the projection of the pupil onto the retina, which displaced abnormally during eye movements. By changing the position of the eye along the axis of the lens in relation to the crossing point of the bundle, the degree to which the displacement was abnormal could be varied, For various displacement rates ranging from 25% to 120 and 400% of normal, abnormal displacements produced by incidental eye movements remained unnoticed, Only where eye movements were intentional did some of our Ss report shifts of the perceived image. It is suggested that the organism copes with the image displacement resulting from the ever-present incidental eye movements not by compensation but by ignoring them.     

On becoming a leader: Effects of gender and cultural differences on power distance reduction

The present research focused on power processes in a simulated organizational structure consisting of three hierarchical levels occupied by different numbers of mules and females. Subjects were presented with a chart showing the organizational hierarchy of which they were a member placed at the lowest level, and asked to nominate any person for the leader position vacated by the current incumbent. The results of Experiment I (n = 88 Dutch male and female university students) showed that male subjects strongly overnominated themselves, whereas a majority of the female subjects nominated either self or another female. Of the others that were nominated by both males and females, almost all were occupants of positions immediately below the leader position, indicating the normative influence of a bureaucratic rule of leader succession. Experiment 2 was a replicational study carried out in a different culture (n = lOl Polish male and female university students). Polish subjects adhered to the bureaucratic rule more strongly than their Dutch counterparts, and both females and males nominated mostly males. Results are discussed with reference to gender self-stereotypes and cultural differences.     

Sensitivity of persons with hearing impairment to visual emotional expression — compensation or deficit?

The research examined whether subjects with hearing impairment would differ from normal hearing subjects in their ability to decode emotions from video stimuli (48 video takes in which two actors portrayed six different emotions). Studies in tactile and visual perception lead one to expect deficits, while there is also some evidence for compensation. Twenty-six subjects with hearing impairment and 26 matched normal hearing subjects participated (average age = 25.5 years; nine female, 17 male subjects in each group). Results indicate that in general subjects with hearing impairment were slightly less successful in decoding emotions from the visual stimuli than the normal hearing subjects. A comparison between highly (loss > 60–90 dBA) and moderately (loss about 30–60 dBA) impaired subjects on the other hand indicated poorer emotion decoding only for the moderately impaired group. Post-hoc analyses indicated that these effects were specific to males. Results are discussed with respect to compensation versus deficit, and with respect to issues of training.     

Lexical integration across saccades in reading

Summary Eye movements were recorded during sentence reading to examine the integration of parafoveal text across fixations. Four viewing conditions were used, each affording full view of the directly fixated word: no preview of the spatially adjacent parafoveal word; preview of its beginning trigram; preview of its beginning four letters; or preview of all its constituent letters. The magnitude of parafoveal-preview benefits (the difference between the no-preview condition and the different parafoveal-preview conditions) was examined as a function of the size of the saccade to the parafoveal target and as a function of the subsequent fixation location at the previewed target. The results revealed no effects of saccade size on parafoveal-preview benefits, but large effects of fixation position during the initial target fixation. Furthermore, parafoveal previews were used during the initial target fixation and during subsequent intratarget refixations. The results support a lexical-text-integration hypothesis which posits that lexical information is integrated across interword fixations and intraword refixations.     

Book reviews

Enlightenment East and West Leonard Angel, 1994 Albany, State University of New York Press 388 pp.

Visions of Power: Imagining Medieval Japanese Buddhism Bernard Faure, trans, by Phyius Brooks, 1996 Princeton, Princeton University Press 329 pp.

Pāli Buddhism. Curzon Studies in Asian Philosophy Frank J. Hoffman & Deegaixe Mahinda (Eds), 1996 Richmond, Curzon Press xiii + 233 pp., ISBN 0 7007 0359 4, hb £40

Friendship East and West: philosophical perspectives Oliver Leaman (Ed.), 1996 Richmond UK, Curzon Press ix + 288 pp., ISBN 0 7007 0358 6, hb £40

Heidegger's Hidden Sources: East Asian Influences on his work Reinhard May, trans, by GRAHAM PARKES, 1996 London, Routledge xviii+ 121 pp., hb £35.00, pb £11.99

The Social Self in Zen and American Pragmatism Steve Odin, 1996 Albany, SUNY Press xvi + 482 pp., ISBN 0 9714 2492 8, pb $24.95

The Art of living. Aesthetics of the Ordinary in World Spiritual Traditions Crispin Sartwell, 1995 Albany, State University of New York Press xiv+ 163 pp., hb

East‐West Encounters in Philosophy and Religion Ninian Smart & B. Srinivasa Murthy (Eds), 1997 London, Sangam Books xxiii + 411 pp., ISBN 0 8613 2375 0, hb £24.95

Confucianism and Christianity: a comparative study of Jen and Agape Xinzhong Yao, 1996 Brighton, Sussex Academic Press viii+ 164 pp., ISBN 1 8987 2325 7, hb £35 and $55