The Goldmeier Effect in Adults and Children: Environmental, Retinal, and Phenomenal Influences on Judgments of Visual Symmetry

Perception ◽  
1987 ◽  
Vol 16 (1) ◽  
pp. 29-39 ◽  
Author(s):  
Celia B Fisher ◽  
Maria P Fracasso
Keyword(s):  
Age Groups ◽  
Head Tilt ◽  
Head Rotation ◽  
Vertical Axis ◽  
Horizontal Axis ◽  
Head Orientation ◽  
Stimulus Complexity ◽  
Adults And Children ◽  
Symmetry Perception ◽  
Retinal Information

Adults judge that patterns symmetrical about the vertical axis are more similar to standard patterns symmetrical about both major orthogonal axes than are patterns which are symmetrical only about the horizontal axis (the Goldmeier effect). Thus, symmetry about the vertical axis is more salient for adults than symmetry about the horizontal axis. Two experiments are reported in which subjects from three age groups (preschool, 8 years old, and adult) were given Goldmeier problems under different conditions. In experiment 1 three head-tilt conditions were used (0°, 45°, 90°); in experiment 2 there were four conditions defined by head orientation (0°, 90°) and phenomenal instructions (top of figure at 0° or at 90°). In both experiments, increasing head tilt from 0° decreased the consistency with which the environmentally vertical pattern was chosen. Noncorrespondence between the three spatial frameworks (environmental, retinal, and phenomenal) failed to produce biases in favor of either retinal-egocentric or phenomenal systems. For rotated adult subjects in experiment 2, 0° phenomenal instructions strengthened an environmental bias, and 90° phenomenal instructions shifted responses toward a retinal bias. These findings provide strong refutation of explanations for symmetry perception that are based solely upon the anatomical symmetry of the visual system. The data also fail to support arguments for environmental or phenomenal frameworks as singular influences. The results are best explained in terms of failure of constancy mechanisms to coordinate environmental and retinal information as a function of degree of head rotation and stimulus complexity.

Gravity-Specific Adaptation of the Angular Vestibuloocular Reflex: Dependence on Head Orientation With Regard to Gravity

2003 ◽  
Vol 89 (1) ◽  
pp. 571-586 ◽  
Author(s):  
Sergei B. Yakushin ◽  
Theodore Raphan ◽  
Bernard Cohen
Keyword(s):  
Head Tilt ◽  
Vertical Axis ◽  
Continuous Functions ◽  
Head Position ◽  
Head Orientation ◽  
Vestibuloocular Reflex ◽  
Specific Adaptation ◽  
Gain Adaptation ◽  
Bias Level ◽  
Single State

The gain of the vertical angular vestibuloocular reflex (aVOR) was adaptively altered by visual-vestibular mismatch during rotation about an interaural axis, using steps of velocity in three head orientations: upright, left-side down, and right-side down. Gains were decreased by rotating the animal and visual surround in the same direction and increased by visual and surround rotation in opposite directions. Gains were adapted in one head position (single-state adaptation) or decreased with one side down and increased with the other side down (dual-state adaptation). Animals were tested in darkness using sinusoidal rotation at 0.5 Hz about an interaural axis that was tilted from horizontal to vertical. They were also sinusoidally oscillated from 0.5 to 4 Hz about a spatial vertical axis in static tilt positions from yaw to pitch. After both single- and dual-state adaptation, gain changes were maximal when the monkeys were in the position in which the gain had been adapted, and the gain changes progressively declined as the head was tilted away from that position. We call this gravity-specific aVOR gain adaptation. The spatial distribution of the specific aVOR gain changes could be represented by a cosine function that was superimposed on a bias level, which we called gravity-independent gain adaptation. Maximal gravity-specific gain changes were produced by 2–4 h of adaptation for both single- and dual-state adaptations, and changes in gain were similar at all test frequencies. When adapted while upright, the magnitude and distribution of the gravity-specific adaptation was comparable to that when animals were adapted in side-down positions. Single-state adaptation also produced gain changes that were independent of head position re gravity particularly in association with gain reduction. There was no bias after dual-state adaptation. With this difference, fits to data obtained by altering the gain in separate sessions predicted the modulations in gain obtained from dual-state adaptations. These data show that the vertical aVOR gain changes dependent on head position with regard to gravity are continuous functions of head tilt, whose spatial phase depends on the position in which the gain was adapted. From their different characteristics, it is likely that gravity-specific and gravity-independent adaptive changes in gain are produced by separate neural processes. These data demonstrate that head orientation to gravity plays an important role in both orienting and tuning the gain of the vertical aVOR.

Responses of Monkey Vestibular-Only Neurons to Translation and Angular Rotation

2006 ◽  
Vol 96 (6) ◽  
pp. 2915-2930 ◽  
Author(s):  
Wu Zhou ◽  
Bing Feng Tang ◽  
Shawn D. Newlands ◽  
W. M. King
Keyword(s):  
Head Tilt ◽  
High Sensitivity ◽  
Vertical Axis ◽  
Head Movements ◽  
Head Orientation ◽  
Angular Rotation ◽  
Discharge Rates ◽  
Static Head ◽  
Low Sensitivity ◽  
Head Translation

Single-unit recordings were obtained from central vestibular neurons in three monkeys during passive head movements. Neurons that discharged in relation to head translation or changes in head orientation, but not eye movement (“vestibular-only,” n = 154), were examined in detail. Neuronal discharge rates were analyzed during four stimulus conditions: sinusoidal head translation in the horizontal plane (0.2–4 Hz, 0.2 g peak acceleration), static head tilt in the vertical plane (±20°), oscillatory head tilt (0.5–2 Hz), and sinusoidal angular rotation about an earth-vertical axis (0.5 or 1 Hz). Vestibular-only cells were divided into two groups based on the regularity of their spontaneous discharge rates (CV*). One group (low-sensitivity units) exhibited regular discharge rates (CV* < 0.2), weak discharge modulation during head translation (<25 spikes · s−1 · g−1 at f = 1 Hz), and persistent discharge rates related to static head tilt (0.68 spikes · s−1 · °−1 of head tilt). The second group (high sensitivity neurons) exhibited irregular discharge rates (CV* > 0.2), strong discharge modulation during head translation (∼100 spikes · s−1 · g−1 at f = 1 Hz), and little or no change in discharge rate during static head tilt (0.32 spikes · s−1 · °−1). The firing rates of some neurons in both groups were modulated during rotation about an earth-vertical axis (42%), but the modulation was greater for neurons classified as high sensitivity units. Previous reports have described neurons similar to the high sensitivity group; however, the low sensitivity or tilt neurons have not previously been characterized. Significantly, recent theoretical models have predicted neurons with discharge patterns similar to those of low- and high-sensitivity neurons.

scholarly journals Does Head Orientation Influence 3D Facial Imaging? A Study on Accuracy and Precision of Stereophotogrammetric Acquisition

2021 ◽  
Vol 18 (8) ◽  
pp. 4276
Author(s):  
Giuditta Battistoni ◽  
Diana Cassi ◽  
Marisabel Magnifico ◽  
Giuseppe Pedrazzi ◽  
Marco Di Blasio ◽  
...  
Keyword(s):  
Head Rotation ◽  
Anthropometric Measurements ◽  
Head Orientation ◽  
3D Images ◽  
Face Shape ◽  
Operator Error ◽  
Accuracy And Precision ◽  
Error Magnitude ◽  
Repeatability And Reproducibility ◽  
Head Positions

This study investigates the reliability and precision of anthropometric measurements collected from 3D images and acquired under different conditions of head rotation. Various sources of error were examined, and the equivalence between craniofacial data generated from alternative head positions was assessed. 3D captures of a mannequin head were obtained with a stereophotogrammetric system (Face Shape 3D MaxiLine). Image acquisition was performed with no rotations and with various pitch, roll, and yaw angulations. On 3D images, 14 linear distances were measured. Various indices were used to quantify error magnitude, among them the acquisition error, the mean and the maximum intra- and inter-operator measurement error, repeatability and reproducibility error, the standard deviation, and the standard error of errors. Two one-sided tests (TOST) were performed to assess the equivalence between measurements recorded in different head angulations. The maximum intra-operator error was very low (0.336 mm), closely followed by the acquisition error (0.496 mm). The maximum inter-operator error was 0.532 mm, and the highest degree of error was found in reproducibility (0.890 mm). Anthropometric measurements from alternative acquisition conditions resulted in significantly equivalent TOST, with the exception of Zygion (l)–Tragion (l) and Cheek (l)–Tragion (l) distances measured with pitch angulation compared to no rotation position. Face Shape 3D Maxiline has sufficient accuracy for orthodontic and surgical use. Precision was not altered by head orientation, making the acquisition simpler and not constrained to a critical precision as in 2D photographs.

scholarly journals The Pelvic Incidence Stratified Sagittal Spinopelvic Alignment in Asymptomatic Chinese Population With Different Age Groups

2021 ◽  
pp. 219256822198964
Author(s):  
Siyu Zhou ◽  
Zhuoran Sun ◽  
Wei Li ◽  
Da Zou ◽  
Weishi Li
Keyword(s):  
Chinese Population ◽  
Pelvic Incidence ◽  
Sagittal Alignment ◽  
Age Groups ◽  
Vertical Axis ◽  
Elderly Subjects ◽  
Sagittal Vertical Axis ◽  
Cross Sectional ◽  
Sagittal Parameters ◽  
Very High

Study Design: Cross-sectional study. Objective: To provide the age- and pelvic incidence-related variations of sagittal alignment in asymptomatic Chinese population. Methods: This study recruited asymptomatic adult subjects. All subjects undertook the standing whole spinal radiograph and the sagittal parameters were measured: sagittal vertical axis (SVA), T1 pelvic angle (TPA), lumbar lordosis (LL), thoracic kyphosis (TK), pelvic incidence (PI) and pelvic tilt (PT). All subjects were divided into young, middle aged and elderly groups, then each age group was further divided into 5 subgroups (very low, low, average, high and very high) based on PI values. The relations between PI, age and other parameters were evaluated. The differences in sagittal parameters of each PI subgroup were compared. Results: 546 subjects were included with an average age of 38.6 years (18 to 81). The number of subjects over 70 years and with very low PI was relatively small. The average of PI, TPA, PT and LL were 45.9° ± 8.4°, 6.4° ± 6.2°, 11.9° ± 6.6° and 49.2° ± 10.1°, respectively. SVA, TPA, TK and PT increased with age ( P < 0.05), while SVA, TPA, PT, PI-LL also increased with PI ( P < 0.05). LL, PT, TPA, PI-LL and LL-TK were different among the 5 PI subgroups ( P < 0.05). However, the values of LL in elderly subjects with high and very high PI were similar. Conclusion: The age- and PI-related variations in sagittal alignment of Chinese population were provided. The sagittal parameters were significantly influenced by age and PI. The individual pelvic morphology should be carefully considered during the assessment and restoration of sagittal balance.

Three‐component sonde orientation in a deviated well

Geophysics ◽  
1990 ◽  
Vol 55 (10) ◽  
pp. 1386-1388 ◽  
Author(s):  
M. Becquey ◽  
M. Dubesset
Keyword(s):  
Hydraulic Fracturing ◽  
Coordinate System ◽  
Vertical Plane ◽  
Vertical Axis ◽  
Horizontal Axis ◽  
Orthogonal Coordinate System ◽  
Coordinate Rotation ◽  
Orthogonal Components ◽  
Particle Velocities

In well seismics, when operating with a three‐component tool, particle velocities are measured in the sonde coordinate system but are often needed in other systems (e.g., source‐bound or geographic). When the well is vertical, a change from the three orthogonal components of the sonde to another orthogonal coordinate system can be performed through one rotation around the vertical axis and, if necessary, another one around a horizontal axis (Hardage, 1983). If the well is deviated, the change of coordinate system remains easy in the case when the source is located at the vertical of the sonde, or in the case when the source stands in the vertical plane defined by the local well axis. In the general case (offset VSPs or walkaways) or when looking for unknown sources (such as microseismic emissions induced by hydraulic fracturing), coordinate rotation may still be performed, provided that we first get back to a situation in which one of the axes is vertical.

Modeling 3-D Slow Phase Velocity Estimation During Off-Vertical-Axis Rotation (OVAR)

1992 ◽  
Vol 2 (1) ◽  
pp. 1-14
Author(s):  
Charles Schnabolk ◽  
Theodore Raphan
Keyword(s):  
Polarization Vector ◽  
Vertical Axis ◽  
Cross Product ◽  
Interesting Property ◽  
Velocity Estimation ◽  
Three Dimensions ◽  
Slow Phase ◽  
Head Orientation ◽  
Head Velocity ◽  
Axis Rotation

Off-vertical-axis rotation (OVAR) in darkness generates continuous compensatory eye velocity. No model has yet been presented that defines the signal processing necessary to estimate head velocity in three dimensions for arbitrary rotations during OVAR. The present study develops a model capable of estimating all 3 components of head velocity in space accurately. It shows that processing of two patterns of otolith activation, one delayed with respect to the other, for each plane of eye movement is not sufficient. (A pattern in this context is an array of signals emanating from the otoliths. Each component of the array is a signal corresponding to a class of otolith hair cells with a given polarization vector as described by Tou and Gonzalez in 1974.) The key result is that estimation of head velocity in space can be achieved by processing three temporally displaced patterns, each representing a sampling of gravity as the head rotates. A vector cross product of differences between pairs of the sampled gravity vectors implements the estimation. An interesting property of this model is that the component of velocity about the axis of rotation reduces to that derived previously using the pattern estimator model described by Raphan and Schnabolk in 1988 and Fanelli et al in 1990. This study suggests that the central nervous system (CNS) maintains a current as well as 2 delayed representations of gravity at every head orientation during rotation. It also suggests that computing vector cross products and implementing delays may be fundamental operations in the CNS for generating orientation information associated with motion.

Interstitial Nucleus of Cajal Encodes Three-Dimensional Head Orientations in Fick-Like Coordinates

2007 ◽  
Vol 97 (1) ◽  
pp. 604-617 ◽  
Author(s):  
Eliana M. Klier ◽  
Hongying Wang ◽  
J. Douglas Crawford
Keyword(s):  
Coordinate System ◽  
Degrees Of Freedom ◽  
Three Dimensional ◽  
Semicircular Canals ◽  
Head Rotation ◽  
Head Orientation ◽  
Interstitial Nucleus Of Cajal ◽  
The Gaze ◽  
Behavioral Constraints ◽  
The Right

Two central, related questions in motor control are 1) how the brain represents movement directions of various effectors like the eyes and head and 2) how it constrains their redundant degrees of freedom. The interstitial nucleus of Cajal (INC) integrates velocity commands from the gaze control system into position signals for three-dimensional eye and head posture. It has been shown that the right INC encodes clockwise (CW)-up and CW-down eye and head components, whereas the left INC encodes counterclockwise (CCW)-up and CCW-down components, similar to the sensitivity directions of the vertical semicircular canals. For the eyes, these canal-like coordinates align with Listing’s plane (a behavioral strategy limiting torsion about the gaze axis). By analogy, we predicted that the INC also encodes head orientation in canal-like coordinates, but instead, aligned with the coordinate axes for the Fick strategy (which constrains head torsion). Unilateral stimulation (50 μA, 300 Hz, 200 ms) evoked CW head rotations from the right INC and CCW rotations from the left INC, with variable vertical components. The observed axes of head rotation were consistent with a canal-like coordinate system. Moreover, as predicted, these axes remained fixed in the head, rotating with initial head orientation like the horizontal and torsional axes of a Fick coordinate system. This suggests that the head is ordinarily constrained to zero torsion in Fick coordinates by equally activating CW/CCW populations of neurons in the right/left INC. These data support a simple mechanism for controlling head orientation through the alignment of brain stem neural coordinates with natural behavioral constraints.

scholarly journals Development of wireless vertical bar spinner combat robot

2020 ◽  
Vol 18 (2) ◽  
pp. 759
Author(s):  
Amirul Syafiq Sadun ◽  
Jamaludin Jalani ◽  
Suziana Ahmad ◽  
Amiera Saryati Sadun ◽  
Sumaiya Mashori
Keyword(s):  
High Power ◽  
Vertical Axis ◽  
Horizontal Axis ◽  
Robot Design ◽  
Performance Requirement ◽  
Science Centre ◽  
National Science ◽  
And Performance

Recently, combat robot competition has become one of the most famous engineering competitions among schools and universities. The robots are usually built with a destructive weapon, which can immobilize or disable opponent’s robot and win the match. Despite the variety of robot design and concept, the trend has shown that most of the local contestant tend to design a horizontal axis weapon type. In this project, a wireless vertical axis bar spinner combat robot is designed and developed for the 3rd Malaysia Combat Robot Competition which was held at National Science Centre (PSN) in 2017. The robot is controlled using radio control (RC) and powered by a highly discharge 22.2V Lithium Polymer (LiPo) chemical battery. Furthermore, related analysis has been conducted to meet the design and performance requirement of the competition. With the DC brush motor and thick metal bar rotating in vertical axis, the robot has proven to produce high power, torque and speed during the competition.

scholarly journals Clinical features and outcome of Covid-19 in individuals without Comorbidities. Do children have the advantage?

2021 ◽  
Vol 8 (2) ◽  
pp. 88-93
Author(s):  
Dr. Abhishek Kumar ◽  
◽  
Dr. Nilu Kumari ◽  
Dr. Ranjeet Kumar Singh ◽  
Dr. Alok Kumar ◽  
...  
Keyword(s):  
Severe Disease ◽  
Age Groups ◽  
Asymptomatic Infection ◽  
Healthy Individuals ◽  
Adult Group ◽  
Middle Aged ◽  
History Of ◽  
Adults And Children ◽  
The Mean ◽  
Respiratory Complaints

Objective: Information regarding clinical characteristics and the natural course of COVID-19amongst individuals without comorbidities is scarce. We therefore conducted a retrospectiveobservational study to decipher the disease profile in two different age groups, middle-aged (40-59years) and children (up to 12 years). Method: Study was conducted by reviewing the medicalrecords of all patients in the desired age groups and excluding all those with preexisting illness(called comorbidities). Result: A total of 154 and 27 patients were enrolled and studied in themiddle-aged adults and children group respectively. Males dominated in both groups with a sex ratioof 2.9 in adults and 1.7 in children. Most of the children (92.5%) had a history of exposure from aninfected family member, while in the adult group history of contact was present in 71.4% ofpatients.62.9% of children had an asymptomatic infection which was significantly higher than 22.8%in adults. Cough and fever were the most common symptoms in both age groups, but adults weremore likely to have respiratory complaints when compared with children.11 (7.1%) patients in theadult group had severe disease while in the children group none had severe disease. Similarly in theadult group 11 patients required ICU admission, but none in the children group. The mean durationof RTPCR positivity was similar in both groups. There was 1 (0.6%) expiry in the adult groupwhereas none in children. Conclusion: Healthy individuals in both middle-aged and children grouptend to have milder disease and both harbour the virus for the almost same duration but adults aremore symptomatic in comparison to children and hence children are more likely to be potentialasymptomatic carrier and transmitter of infection.

Human Updating of Visual Motion Direction During Head Rotations

2008 ◽  
Vol 99 (5) ◽  
pp. 2558-2576
Author(s):  
Mario Ruiz-Ruiz ◽  
Julio C. Martinez-Trujillo
Keyword(s):  
Visual Motion ◽  
Human Subjects ◽  
Head Tilt ◽  
Head Rotation ◽  
Three Dimensions ◽  
Spatial Updating ◽  
Motion Direction ◽  
Direction Discrimination ◽  
Head Rotations ◽  
Stimulus Direction

Previous studies have demonstrated that human subjects update the location of visual targets for saccades after head and body movements and in the absence of visual feedback. This phenomenon is known as spatial updating. Here we investigated whether a similar mechanism exists for the perception of motion direction. We recorded eye positions in three dimensions and behavioral responses in seven subjects during a motion task in two different conditions: when the subject's head remained stationary and when subjects rotated their heads around an anteroposterior axis (head tilt). We demonstrated that after head-tilt subjects updated the direction of saccades made in the perceived stimulus direction (direction of motion updating), the amount of updating varied across subjects and stimulus directions, the amount of motion direction updating was highly correlated with the amount of spatial updating during a memory-guided saccade task, subjects updated the stimulus direction during a two-alternative forced-choice direction discrimination task in the absence of saccadic eye movements (perceptual updating), perceptual updating was more accurate than motion direction updating involving saccades, and subjects updated motion direction similarly during active and passive head rotation. These results demonstrate the existence of an updating mechanism for the perception of motion direction in the human brain that operates during active and passive head rotations and that resembles the one of spatial updating. Such a mechanism operates during different tasks involving different motor and perceptual skills (saccade and motion direction discrimination) with different degrees of accuracy.

Sign in / Sign up

Export Citation Format

Share Document