Effects of Hand Orientation and Delay on the Verbal Judgment of Haptically Perceived Orientation

We examined the haptic perception of orientations of a single bar throughout the horizontal plane using a verbal response: participants were to assign a number of minutes to the orientation of a bar defined with respect to the stimulus table. Performance was found to be systematically biased. Deviations were consistent with, yet much smaller than, those resulting from haptic motor matching tasks. The size and direction of the deviations were found to correlate with hand orientation, and not to depend on spatial location per se, suggesting a role for hand-centred reference frames in biasing performance. Delaying the response by 10 s led to a small improvement only of right-hand perceptions, indicating different hemispheric involvement in processes involved in retaining and/or recoding of haptic orientation information. Also the haptic oblique effect was found with the current verbal response. Importantly, it was affected neither by hand orientation nor by delay, suggesting that the oblique effect is independent of the aforementioned deviations in orientation perception.

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Reference frames and haptic perception of orientation: Body and head tilt effects on the oblique effect

Perception & Psychophysics ◽

10.3758/bf03194419 ◽

2001 ◽

Vol 63 (3) ◽

pp. 541-554 ◽

Cited By ~ 65

Author(s):

Marion Luyat ◽

Edouard Gentaz ◽

Tony Regia Corte ◽

Michel Guerraz

Keyword(s):

Haptic Perception ◽

Reference Frames ◽

Head Tilt ◽

Oblique Effect

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The Haptic ‘Oblique Effect’ in Children's and Adults' Perception of Orientation

Perception ◽

10.1068/p240631 ◽

1995 ◽

Vol 24 (6) ◽

pp. 631-646 ◽

Cited By ~ 51

Author(s):

Edouard Gentaz ◽

Yvette Hatwell

Keyword(s):

Horizontal Plane ◽

Haptic Perception ◽

Sagittal Plane ◽

Oblique Effect ◽

The Other ◽

Older Children ◽

Other Hand ◽

Left And Right ◽

Plane Scanning ◽

Effect Of Age

The haptic perception of vertical, horizontal, and diagonal orientations was studied in children (aged 7 and 9 years) and in adults. The purpose was to test the hypothesis that the haptic oblique effect results from the different scanning movements at work when one hand explores an oblique standard and the other hand sets the response rod. In experiment 1, blindfolded subjects reproduced the orientation of a standard rod presented in either the frontal, the horizontal, or the sagittal plane, and this task was achieved either ipsilaterally (the same hand explored the standard and set the response rod) or contralaterally (one hand explored the standard and the other hand set the response rod). Since, in the sagittal plane, scanning movements are analogous when the left and right hands explore oblique orientations, no oblique effect should be observed in this condition if the hypothesis is valid. Moreover, a development effect should be observed, since young children generally rely more on movement coding than do older children and adults. Results did not support these predictions: the same oblique effect appeared in the frontal and the sagittal planes both in the ipsilateral and in the contralateral condition, and the effect of age was not in the direction predicted by the hypothesis. The results were consistent with the hypothesis in the horizontal plane only. Experiments 2 and 3 provided further tests of this hypothesis but both failed to support it. Taken together, the results of these three experiments did not support the assumption and it is suggested that the haptic oblique effect may be linked to the gravitational cues provided by the arm—hand system when it acts in the three spatial planes.

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Edge orientation perception during active touch

Journal of Neurophysiology ◽

10.1152/jn.00280.2018 ◽

2018 ◽

Vol 120 (5) ◽

pp. 2423-2429 ◽

Cited By ~ 3

Author(s):

Derek Olczak ◽

Vaishnavi Sukumar ◽

J. Andrew Pruszynski

Keyword(s):

Motor System ◽

Active Touch ◽

Contact Forces ◽

Edge Orientation ◽

Passive Touch ◽

Per Se ◽

Orientation Perception ◽

Psychophysical Studies ◽

Psychophysical Task ◽

Better Than

Previous studies investigating the perceptual attributes of tactile edge orientation processing have applied their stimuli to an immobilized fingertip. Here we tested the perceptual attributes of edge orientation processing when participants actively touched the stimulus. Our participants moved their finger over two pairs of edges, one pair parallel and the other nonparallel to varying degrees, and were asked to identify which of the two pairs was nonparallel. In addition to the psychophysical estimates of edge orientation acuity, we measured the speed at which participants moved their finger and the forces they exerted when moving their finger over the stimulus. We report four main findings. First, edge orientation acuity during active touch averaged 12.4°, similar to that previously reported during passive touch. Second, on average, participants moved their finger over the stimuli at ~20 mm/s and exerted contact forces of ~0.3 N. Third, there was no clear relationship between how people moved their finger or how they pressed on the stimulus and their edge orientation acuity. Fourth, consistent with previous work testing tactile spatial acuity, we found a significant correlation between fingertip size and orientation acuity such that people with smaller fingertips tended to have better orientation acuity. NEW & NOTEWORTHY Edge orientation acuity expressed by the motor system during manipulation is many times better than edge orientation acuity assessed in psychophysical studies where stimuli are applied to a passive fingertip. Here we show that this advantage is not because of movement per se because edge orientation acuity assessed in a psychophysical task, where participants actively move their finger over the stimuli, yields results similar to previous passive psychophysical studies.

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Orientation Encoding and Viewpoint Invariance in Face Recognition: Inferring Neural Properties from Large-Scale Signals

The Neuroscientist ◽

10.1177/1073858418769554 ◽

2018 ◽

Vol 24 (6) ◽

pp. 582-608 ◽

Cited By ~ 10

Author(s):

Fernando M. Ramírez

Keyword(s):

Face Recognition ◽

Visual Processing ◽

Large Scale ◽

Bilateral Symmetry ◽

Distributed Network ◽

Face Area ◽

Orientation Information ◽

Orientation Perception ◽

Multivariate Pattern

Viewpoint-invariant face recognition is thought to be subserved by a distributed network of occipitotemporal face-selective areas that, except for the human anterior temporal lobe, have been shown to also contain face-orientation information. This review begins by highlighting the importance of bilateral symmetry for viewpoint-invariant recognition and face-orientation perception. Then, monkey electrophysiological evidence is surveyed describing key tuning properties of face-selective neurons—including neurons bimodally tuned to mirror-symmetric face-views—followed by studies combining functional magnetic resonance imaging (fMRI) and multivariate pattern analyses to probe the representation of face-orientation and identity information in humans. Altogether, neuroimaging studies suggest that face-identity is gradually disentangled from face-orientation information along the ventral visual processing stream. The evidence seems to diverge, however, regarding the prevalent form of tuning of neural populations in human face-selective areas. In this context, caveats possibly leading to erroneous inferences regarding mirror-symmetric coding are exposed, including the need to distinguish angular from Euclidean distances when interpreting multivariate pattern analyses. On this basis, this review argues that evidence from the fusiform face area is best explained by a view-sensitive code reflecting head angular disparity, consistent with a role of this area in face-orientation perception. Finally, the importance is stressed of explicit models relating neural properties to large-scale signals.

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Mulifractal phase transitions: the origin of self-organized criticality in earthquakes

Nonlinear Processes in Geophysics ◽

10.5194/npg-1-191-1994 ◽

1994 ◽

Vol 1 (2/3) ◽

pp. 191-197 ◽

Cited By ~ 17

Author(s):

C. Hooge ◽

S. Lovejoy ◽

D. Schertzer ◽

S. Pecknold ◽

J.-F. Malouin ◽

...

Keyword(s):

Phase Transition ◽

Spatial Distribution ◽

Phase Transitions ◽

Horizontal Plane ◽

Spatial Location ◽

Seismic Process ◽

First Order ◽

Self Organized ◽

Self Organized Criticality ◽

Model Independent

Abstract. Fractal and occasionally multifractal behaviour has been invoked to characterize (independently of their magnitude) the spatial distribution of seismic epicenters, whereas more recently, the frequency distribution of magnitudes (irrespective of their spatial location) has been considered as a manifestation of Self-Organized Criticality (SOC). In this paper we relate these two aspects on rather general grounds, (i.e. in a model independent way), and further show that this involves a non-classical SOC. We consider the multifractal characteristics of the projection of the space-time seismic process onto the horizontal plane whose values are defined by the measured ground displacements, we show that it satisfies the requirements for a first order multifractal phase transition and by implication for a non-classical SOC. We emphasize the important consequences of the stochastic alternative to the classical (deterministic) SOC.

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Orientation Discrimination at Isoluminance

Perception ◽

10.1068/v96l1202 ◽

1996 ◽

Vol 25 (1_suppl) ◽

pp. 127-127

Author(s):

T E Reisbeck ◽

K R Gegenfurtner

Keyword(s):

Oblique Effect ◽

Sine Wave ◽

Orientation Discrimination ◽

Stimulus Contrast ◽

Moving Stimuli ◽

Orientation Contrast ◽

Spatial Frequencies ◽

Orientation Perception ◽

Sine Wave Gratings ◽

Contrast Thresholds

Colour and form are important attributes of the objects in our visual environment. We tested the hypothesis that colour and orientation are processed independently in the visual system. Orientation perception for stimuli defined by luminance is characterised by a decrease in thresholds with increasing stimulus contrast, and by a strong oblique effect: stimuli along the horizontal or vertical axes are discriminated more easily. We determined orientation discrimination thresholds for stationary, slow (1 Hz) or fast (8 Hz) moving sine-wave gratings (1 cycle deg−1) defined by luminance or isoluminant (red — green) contrast. In a 4AFC paradigm, three of four stimulus patches were identical and the fourth differed in orientation, contrast, or in both. When we measured orientation discrimination thresholds as a function of stimulus contrast, thresholds decreased for all stimuli with increasing contrast. At all temporal frequencies the functions relating orientation thresholds to stimulus contrast had similar shapes for luminance and isoluminant gratings. On a cone-contrast metric, thresholds for stationary and slowly moving stimuli were consistently lower for isoluminant compared to luminance stimuli. For fast-moving stimuli orientation thresholds were similar for both kinds of gratings. For both types of stimuli a marked oblique effect was observed. To characterise processing of contrast and orientation completely, we measured simultaneous thresholds for contrast and orientation. The shapes of the resulting two-dimensional threshold contours were similar for luminance and isoluminant gratings, indicating similar rules for combining differences in contrast and orientation. We conclude that processing of isoluminant and luminance stimuli undergoes the same neural processing at least for the low spatial frequencies used here.

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Three-dimensional tuning of head direction cells in rats

Journal of Neurophysiology ◽

10.1152/jn.00880.2017 ◽

2019 ◽

Vol 121 (1) ◽

pp. 4-37 ◽

Cited By ~ 16

Author(s):

Michael E. Shinder ◽

Jeffrey S. Taube

Keyword(s):

Horizontal Plane ◽

Reference Frames ◽

Three Dimensional ◽

Vertical Axis ◽

Ventral Surface ◽

Three Dimensions ◽

Head Direction ◽

Horizontal Canal ◽

Cell Responses ◽

The Earth

Head direction (HD) cells fire when the animal faces that cell’s preferred firing direction (PFD) in the horizontal plane. The PFD response when the animal is oriented outside the earth-horizontal plane could result from cells representing direction in the plane of locomotion or as a three-dimensional (3D), global-referenced direction anchored to gravity. To investigate these possibilities, anterodorsal thalamic HD cells were recorded from restrained rats while they were passively positioned in various 3D orientations. Cell responses were unaffected by pitch or roll up to ~90° from the horizontal plane. Firing was disrupted once the animal was oriented >90° away from the horizontal plane and during inversion. When rolling the animal around the earth-vertical axis, cells were active when the animal’s ventral surface faced the cell’s PFD. However, with the rat rolled 90° in an ear-down orientation, pitching the rat and rotating it around the vertical axis did not produce directionally tuned responses. Complex movements involving combinations of yaw-roll, but usually not yaw-pitch, resulted in reduced directional tuning even at the final upright orientation when the rat had full visual view of its environment and was pointing in the cell’s PFD. Directional firing was restored when the rat’s head was moved back-and-forth. There was limited evidence indicating that cells contained conjunctive firing with pitch or roll positions. These findings suggest that the brain’s representation of directional heading is derived primarily from horizontal canal information and that the HD signal is a 3D gravity-referenced signal anchored to a direction in the horizontal plane. NEW & NOTEWORTHY This study monitored head direction cell responses from rats in three dimensions using a series of manipulations that involved yaw, pitch, roll, or a combination of these rotations. Results showed that head direction responses are consistent with the use of two reference frames simultaneously: one defined by the surrounding environment using primarily visual landmarks and a second defined by the earth’s gravity vector.

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Sound localization and word discrimination in reverberant environment in children with developmental dyslexia

Arquivos de Neuro-Psiquiatria ◽

10.1590/0004-282x20150005 ◽

2015 ◽

Vol 73 (4) ◽

pp. 314-320

Author(s):

Wendy Castro-Camacho ◽

Yolanda Peñaloza-López ◽

Santiago J. Pérez-Ruiz ◽

Felipe García-Pedroza ◽

Ana L. Padilla-Ortiz ◽

...

Keyword(s):

Sound Localization ◽

Developmental Dyslexia ◽

Horizontal Plane ◽

Poor Performance ◽

Spatial Location ◽

Reverberant Environment ◽

Word Discrimination

Objective Compare if localization of sounds and words discrimination in reverberant environment is different between children with dyslexia and controls. Method We studied 30 children with dyslexia and 30 controls. Sound and word localization and discrimination was studied in five angles from left to right auditory fields (-90o, -45o, 0o, +45o, +90o), under reverberant and no-reverberant conditions; correct answers were compared. Results Spatial location of words in no-reverberant test was deficient in children with dyslexia at 0º and +90o. Spatial location for reverberant test was altered in children with dyslexia at all angles, except –-90o. Word discrimination in no-reverberant test in children with dyslexia had a poor performance at left angles. In reverberant test, children with dyslexia exhibited deficiencies at -45o, -90o, and +45o angles. Conclusion Children with dyslexia could had problems when have to locate sound, and discriminate words in extreme locations of the horizontal plane in classrooms with reverberation.

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