Frame-of-Reference and Hierarchical-Organisation Effects in the Rod-and-Frame Illusion

Perception ◽  
1997 ◽  
Vol 26 (12) ◽  
pp. 1485-1494 ◽  
Author(s):  
Pierluigi Zoccolotti ◽  
Gabriella Antonucci ◽  
Roberta Daini ◽  
Maria Luisa Martelli ◽  
Donatella Spinelli
Keyword(s):  
Visual Field ◽  
Frame Of Reference ◽  
Tilted Frame ◽  
Large Display ◽  
Frame Tilt ◽  
Small Display ◽  
Series Of Experiments ◽  
Visual Characteristics ◽  
Definition Of ◽  
Rod And Frame

Two hypotheses proposed as alternatives by Rock—frame of reference and hierarchical organisation of perception—were tested in a series of experiments with the use of the rod-and-frame illusion. This illusion produces errors in the apparent vertical due to the presence of a tilted frame surrounding the test rod. The apparent vertical is shifted in the direction of the frame tilt. When an upright square was added inside the tilted frame, rod-setting errors varied according to the visual characteristics of the display. In the case of a large display presented in the dark (experiment 1), there continued to be large errors in the direction of the outer-square tilt. This finding supports the frame-of-reference hypothesis, which proposes that the orientation of all objects in the visual field is dominated by the most peripheral reference. In the case of a small display presented in a lit environment (experiments 2 and 3), the direction of errors was the opposite. This latter finding was taken to indicate that the rod was set with reference to the perceived tilt of the inner upright square. Thus, according to a hierarchical-organisation hypothesis, the orientation of an object in the visual field is influenced by objects in the immediate surroundings not by outermost reference. Overall, the results confirm the presence of two qualitatively different classes of orientational phenomena: one is concerned with the definition of egocentric coordinates and one with an object-centred visual representation.

Large Errors in the Perception of Verticality are Generated by Luminance Borders (Integrated across Space) Not by Subjective Borders

Perception ◽  
10.1068/p3070 ◽  
2001 ◽  
Vol 30 (2) ◽  
pp. 177-184
Author(s):  
Donatella Spinelli ◽  
Gabriella Antonucci ◽  
Maria Luisa Martelli ◽  
Pierluigi Zoccolotti
Keyword(s):  
Opposite Direction ◽  
Subjective Contour ◽  
Standard Condition ◽  
Global Orientation ◽  
Tilted Frame ◽  
Frame Tilt ◽  
Visual Vertical ◽  
Perception Of Verticality ◽  
Rod And Frame

The rod-and-frame illusion shows large errors in the judgment of visual vertical in the dark if the frame is large and there are no other visible cues (Witkin and Asch, 1948 Journal of Experimental Psychology38 762–782). Three experiments were performed to investigate other characteristics of the frame critical for generating these large errors. In the first experiment, the illusion produced by an 11° tilted frame made by luminance borders (standard condition) was considerably larger than that produced by a subjective-contour frame. In the second experiment, with a 33° frame tilt, the illusion was in the direction of frame tilt with a luminance-border frame but in the opposite direction in the subjective-contour condition. In the third experiment, to contrast the role of local and global orientation, the sides of the frame were made of short separate luminous segments. The segments could be oriented in the same direction as the frame sides, in the opposite direction, or could be vertical. The orientation of the global frame dominated the illusion while local orientation produced much smaller effects. Overall, to generate a large rod-and-frame illusion in the dark, the tilted frame must have luminance, not subjective, contours. Luminance borders do not need to be continuous: a frame made of sparse segments is also effective. The mechanism responsible for the large orientation illusion is driven by integrators of orientation across large areas, not by figural operators extracting shape orientation in the absence of oriented contours.

Recognition of Neonates by Facial-Visual Characteristics

PEDIATRICS ◽  
1984 ◽  
Vol 74 (4) ◽  
pp. 501-504
Author(s):  
Richard H. Porter ◽  
Jennifer M. Cernoch ◽  
Rene D. Balogh
Keyword(s):  
Post Partum ◽  
Newborn Infants ◽  
Sex Identification ◽  
Chance Level ◽  
Visual Features ◽  
Facial Features ◽  
Series Of Experiments ◽  
Visual Characteristics ◽  
Genetically Determined ◽  
Physical Resemblance

A series of experiments investigated the salience of newborn infants' facial-visual features for recognition and sex identification. Within 33 hours post-partum, mothers recognized photographs of their own offspring when presented with those of unrelated neonates. Furthermore, adult subjects were able to match photographs of unfamiliar mothers and their infants, and determine the sex of neonates, at a greater than chance level of accuracy. Although recognizable facial features are presumably genetically determined, maternal recognition of offspring probably results from brief exposure and familiarization as well as physical resemblance between the infant and other familiar family members, including the mother herself.

Obliquity Integration: Variations on a Theme of Delbœuf

Perception ◽  
1993 ◽  
Vol 22 (6) ◽  
pp. 705-712
Author(s):  
Giovanni B Vicario ◽  
Giulio Vidotto ◽  
Elena Zambianchi
Keyword(s):  
Frame Of Reference ◽  
The Other ◽  
Geometrical Illusion ◽  
Tilt Illusion ◽  
Variations On A Theme ◽  
Rod And Frame

An optical—geometrical illusion, described by Delbœuf and not familiar to specialists, is investigated. The results of two experiments show that the divergence between a bar filled with parallel slanting lines and a line drawn above it is clearly related to this angle of the lines which fill the bar. The illusion is already present when this angle is 10°, reaches its maximum at 20°, decreases at 30°, and almost disappears at 40°. These results are similar to those found for the tilt illusion, are slightly different from those found for the rod-and-frame illusion, and differ greatly from those found for the Zöllner illusion. The other variables considered—the distance between the slanting lines filling up the bar, the distance between the upper line and the bar, and the width of the bar—do not influence the illusion as much. Since either the line appears as diverging from the bar, or the bar seems inclined in relation to the line, the illusion should be considered a complex one. The small oblique lines inside the bar induce obliquity in the opposite sense in the display, but which of the elements is seen as diverging from the other depends on which of the two is established as the frame of reference.

scholarly journals Defining cosmetic surgery

2018 ◽  
Vol 1 (1) ◽  
pp. 37-45
Author(s):  
Nicola R Dean ◽  
Kristen Foley ◽  
Paul Ward
Keyword(s):  
Patient Safety ◽  
Cosmetic Surgery ◽  
Invasive Procedure ◽  
Frame Of Reference ◽  
Congenital Defects ◽  
Normal Appearance ◽  
Full Spectrum ◽  
Developmental Abnormalities ◽  
Definition Of ◽  
Agreed Definition

An agreed definition for cosmetic surgery would be helpful for the purposes of discourse on ethics, patient safety, healthcare policy and health economics.  One of the problems with previous attempts at developing a definition is the narrow frame of reference and lack of engagement with the full spectrum of academics and stakeholders.  This review brings together the sociological as well as the surgical literature on the topic of cosmetic surgery and examines societal, ethical and healthcare aspects.  It outlines principles of constructing a definition and presents a provisional definition for further debate, namely:  Cosmetic surgery is defined, for the purposes of a healthcare payer, as any invasive procedure where the primary intention is to achieve what the patient perceives to be a more desirable appearance and where the procedure involves changes to bodily features that have a normal appearance on presentation to the doctor. In contrast, surgery performed with the goal of achieving a normal appearance, where bodily features have an abnormal appearance on presentation due to congenital defects, developmental abnormalities, trauma, infections, tumours or disease does not fall under the definition of cosmetic surgery.  It is a given that “normal appearance” is a subjective notion.  Determining whether patients have a normal or abnormal appearance on presentation will rely on the clinical assessment of the treating doctor.

Location and Functional Definition of Human Visual Motion Organization Using Functional Magnetic Resonance Imaging

2011 ◽  
pp. 18-27
Author(s):  
Tianyi Yan ◽  
Jinglong Wu
Keyword(s):  
Visual Field ◽  
Visual Motion ◽  
Receptive Fields ◽  
Superior Temporal Sulcus ◽  
Object Motion ◽  
Posterior Limb ◽  
Medial Superior Temporal ◽  
Processing Abilities ◽  
Mst Neurons ◽  
Definition Of

In humans, functional imaging studies have found a homolog of the macaque motion complex, MT+, which is suggested to contain both the middle temporal (MT) and medial superior temporal (MST) areas in the ascending limb of the inferior temporal sulcus. In the macaque, the motion-sensitive MT and MST areas are adjacent in the superior temporal sulcus. Electrophysiology has identified several motion-selective regions in the superior temporal sulcus (STS) of the macaque. Two of the best-studied areas include the MT and MST areas. The MT area has strong projections to the adjacent MST area and is typically subdivided into the dorsal (MSTd) and lateral (MSTl) subregions. While MT encodes the basic elements of motion, MST has higher-order motion-processing abilities and has been implicated in the perception of both object motion and self motion. The macaque MST area has been shown to have considerably larger receptive fields than the MT area. The receptive fields of MT cells typically extend only a few degrees into the ipsilateral visual field, while MST neurons have receptive fields that extend well into the ipsilateral visual field. This study tentatively identifies these subregions as the human homologs of the macaque MT and MST areas, respectively (Fig. 1). Putative human MT and MST areas were typically located on the posterior/ventral and anterior/dorsal banks of a dorsal/posterior limb of the inferior temporal sulcus. These locations are similar to their relative positions in the macaque superior temporal sulcus.

scholarly journals “Genes Я us” – Of juis nie? Oor determinisme en voluntarisme by die mens met verwysing na homoseksualiteit

2004 ◽  
Vol 60 (1/2) ◽  
Author(s):  
Johan Buitendag
Keyword(s):  
Religious Experience ◽  
Genome Mapping ◽  
Frame Of Reference ◽  
Human Beings ◽  
Departure Point ◽  
Holistic View ◽  
Brain Functions ◽  
Definition Of ◽  
Sacred Canopy ◽  
Do So

“Genes Я us” – or not? About human determinism and voluntarism, with reference to homosexualityThis article has as its departure point the conviction of some that human genome mapping predisposes human beings genetically and as a consequence, the homosexual person becomes a mere victim of circumstances. Biological determinism and social construc-tionism are not mutually exclusive and although a person is orientated within a web of boundary matters, the depiction of a human being as imago Dei still prevails. A person has the freedom to choose and the responsibility to do so. One’s understanding of reality provides a frame of reference from which a definition of morality is derived. The suggestion of Nancey Murphey to understand reality as a “nonreductive physicalism” is followed. Reductionism in any form is subsequently avoided. A holistic view of humankind in terms of which religious experience is seen as more than some brain functions and people are embedded in a “sacred canopy”, is therefore advocated.

Shrinkage of lung after chemical fixation for analysis of pulmonary structure-function relations

1980 ◽  
Vol 48 (2) ◽  
pp. 382-385 ◽  
Author(s):  
R. W. Mazzone ◽  
S. Kornblau ◽  
C. M. Durand
Keyword(s):  
Structure Function ◽  
Freeze Substitution ◽  
Transpulmonary Pressure ◽  
Vascular Perfusion ◽  
Fixed Tissue ◽  
Linear Dimensions ◽  
Schiff Reagent ◽  
Tissue Shrinkage ◽  
Series Of Experiments ◽  
Definition Of

Glutaraldehyde is widely used to chemically fix lungs for analysis of pulmonary structure-function relations. Accurate interpretation of observations on fixed tissue requires a clear definition of any artifacts, such as tissue shrinkage, resulting from fixation with glutaraldehyde. Two experimental procedures were used in this study to examine possible shrinkage artifacts resulting from fixation of lung by glutaraldehyde. In the first, isolated perfused dog lungs were rapidly frozen at different transpulmonary pressures. Samples were then freeze substituted at -50 degrees C using 70% ethylene glycol with and without fixatives present. In the second series of experiments, the left lungs of mongrel dogs were fixed by vascular perfusion with glutaraldehyde at different transpulmonary pressures. In both series of experiments any changes in linear dimensions resulting from the fixation procedure were measured. Also, the presence of aldehyde was demonstrated by a positive reaction with Schiff reagent. The results demonstrate that lung tissue fixed either by vascular perfusion or freeze substitution tends to shrink to about the same extent. This shrinkage is reasonably constant at about 9% for transpulmonary pressures of 5 and 15 cmH2O and increases to about 15% when the transpulmonary pressure reaches 25 cmH20.

scholarly journals Motivation as a tool for designing lifelong learning robots

2020 ◽  
Vol 27 (4) ◽  
pp. 353-372
Author(s):  
Alejandro Romero ◽  
Francisco Bellas ◽  
José A. Becerra ◽  
Richard J. Duro
Keyword(s):  
Robot Control ◽  
Control Structure ◽  
Autonomous Robots ◽  
Point Of View ◽  
Main Question ◽  
Structured Design ◽  
Design Time ◽  
Real Robot ◽  
Series Of Experiments ◽  
Definition Of

Designing robots has usually implied knowing beforehand the tasks to be carried out and in what domains. However, in the case of fully autonomous robots this is not possible. Autonomous robots need to operate in an open-ended manner, that is, deciding on the most interesting goals to achieve in domains that are not known at design time. This obviously poses a challenge from the point of view of designing the robot control structure. In particular, the main question that arises is how to endow the robot with a designer defined purpose and with means to translate that purpose into operational decisions without any knowledge of what situations the robot will find itself in. In this paper, we provide a formalization of motivation from an engineering perspective that allows for the structured design of purposeful robots. This formalization is based on a definition of the concepts of robot needs and drives, which are related through experience to the appropriate goals in specific domains. To illustrate the process, a motivational system to guide the operation of a real robot is constructed using this approach. A series of experiments carried out over it are discussed providing some insights on the design of purposeful motivated operation.

Relation of Perceptual Style to Measures of Visual Functioning

1967 ◽  
Vol 25 (1) ◽  
pp. 235-236 ◽  
Author(s):  
Gerald V. Barrett ◽  
Patrick A. Cabe ◽  
Carl L. Thornton
Keyword(s):  
Individual Differences ◽  
Visual Functioning ◽  
Perceptual Style ◽  
Visual Characteristics ◽  
Rod And Frame

Measures of Witkin's concept of perceptual style were obtained with a Rod and Frame apparatus for 44 Ss and correlated with individual measures of macular stereopsis and phoria obtained from a Keystone Orthoscope. As none of the Spearman rbos were significant, individual differences in perceptual style appear not to be a function of the measured individual visual characteristics.

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