Motion Direction Discrimination with Tactile Random-Dot Kinematograms

Motion detection is a fundamental sensory function for multiple modalities, including touch, but the mechanisms underlying tactile motion detection are not well understood. While previous findings supported the existence of high-level feature tracking, it remains unclear whether there also exist low-level motion sensing that directly detects a local spatio-temporal correlation in the skin-stimulation pattern. To elucidate this mechanism, we presented, on braille displays, tactile random-dot kinematograms, similar to those widely used in visual motion research, which enables us to independently manipulate feature trackability and various parameters of local motion. We found that a human observer is able to detect the direction of difficult-to-track tactile motions presented to the fingers and palms. In addition, the direction-discrimination performance was better when the stimuli were presented along the fingers than when presented across the fingers. These results indicate that low-level motion sensing, in addition to high-level tracking, contribute to tactile motion perception.

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Human Updating of Visual Motion Direction During Head Rotations

Journal of Neurophysiology ◽

10.1152/jn.00931.2007 ◽

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.

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Different mechanisms for the learning of motion detection vs. the learning of motion direction discrimination

Journal of Vision ◽

10.1167/1.3.29 ◽

2010 ◽

Vol 1 (3) ◽

pp. 29-29 ◽

Cited By ~ 1

Author(s):

S. Koyama ◽

A. Harner ◽

T. Watanabe

Keyword(s):

Motion Detection ◽

Motion Direction ◽

Direction Discrimination

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Difference in perceptual and oculomotor responses revealed by apparent motion stimuli presented with an interstimulus interval

Journal of Neurophysiology ◽

10.1152/jn.00647.2014 ◽

2015 ◽

Vol 113 (9) ◽

pp. 3219-3228 ◽

Cited By ~ 5

Author(s):

Shizuka Nohara ◽

Kenji Kawano ◽

Kenichiro Miura

Keyword(s):

Feature Tracking ◽

Visual Motion ◽

Level Energy ◽

Direction Discrimination ◽

Relative Contrast ◽

Oculomotor Responses ◽

Feature Based ◽

High Level ◽

High Level Feature ◽

Response Direction

To understand the mechanisms underlying visual motion analyses for perceptual and oculomotor responses and their similarities/differences, we analyzed eye movement responses to two-frame animations of dual-grating 3 f5 f stimuli while subjects performed direction discrimination tasks. The 3 f5 f stimulus was composed of two sinusoids with a spatial frequency ratio of 3:5 (3 f and 5 f), creating a pattern with fundamental frequency f. When this stimulus was shifted by 1/4 of the wavelength, the two components shifted 1/4 of their wavelengths and had opposite directions: the 5 f forward and the 3 f backward. By presenting the 3 f5 f stimulus with various interstimulus intervals (ISIs), two visual-motion-analysis mechanisms, low-level energy-based and high-level feature-based, could be effectively distinguished. This is because response direction depends on the relative contrast between the components when the energy-based mechanism operates, but not when the feature-based mechanism works. We found that when the 3 f5 f stimuli were presented with shorter ISIs (<100 ms), and 3 f component had higher contrast, both perceptual and ocular responses were in the direction of the pattern shift, whereas the responses were reversed when the 5 f had higher contrast, suggesting operation of the energy-based mechanism. On the other hand, the ocular responses were almost negligible with longer ISIs (>100 ms), whereas perceived directions were biased toward the direction of pattern shift. These results suggest that the energy-based mechanism is dominant in oculomotor responses throughout ISIs; however, there is a transition from energy-based to feature-tracking mechanisms when we perceive visual motion.

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Bayesian Computation in Recurrent Neural Circuits

Neural Computation ◽

10.1162/08997660460733976 ◽

2004 ◽

Vol 16 (1) ◽

pp. 1-38 ◽

Cited By ~ 138

Author(s):

Rajesh P. N. Rao

Keyword(s):

Motion Detection ◽

Network Architecture ◽

Discrimination Task ◽

Visual Motion ◽

Natural World ◽

Direction Selectivity ◽

Orientation Discrimination ◽

Posterior Probabilities ◽

Motion Direction ◽

Model Network

A large number of human psychophysical results have been successfully explained in recent years using Bayesian models. However, the neural implementation of such models remains largely unclear. In this article, we show that a network architecture commonly used to model the cerebral cortex can implement Bayesian inference for an arbitrary hidden Markov model. We illustrate the approach using an orientation discrimination task and a visual motion detection task. In the case of orientation discrimination, we show that the model network can infer the posterior distribution over orientations and correctly estimate stimulus orientation in the presence of significant noise. In the case of motion detection, we show that the resulting model network exhibits direction selectivity and correctly computes the posterior probabilities over motion direction and position. When used to solve the well-known random dots motion discrimination task, the model generates responses that mimic the activities of evidence-accumulating neurons in cortical areas LIP and FEF. The framework we introduce posits a new interpretation of cortical activities in terms of log posterior probabilities of stimuli occurring in the natural world.

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Complementary mechanisms create direction selectivity in the fly

eLife ◽

10.7554/elife.17421 ◽

2016 ◽

Vol 5 ◽

Cited By ~ 54

Author(s):

Juergen Haag ◽

Alexander Arenz ◽

Etienne Serbe ◽

Fabrizio Gabbiani ◽

Alexander Borst

Keyword(s):

Motion Detection ◽

Visual Motion ◽

Optic Lobe ◽

Direction Selectivity ◽

Neural Computation ◽

Directional Selectivity ◽

Motion Sensing ◽

Null Direction ◽

Preferred Direction ◽

High Degree

How neurons become sensitive to the direction of visual motion represents a classic example of neural computation. Two alternative mechanisms have been discussed in the literature so far: preferred direction enhancement, by which responses are amplified when stimuli move along the preferred direction of the cell, and null direction suppression, where one signal inhibits the response to the subsequent one when stimuli move along the opposite, i.e. null direction. Along the processing chain in the Drosophila optic lobe, directional responses first appear in T4 and T5 cells. Visually stimulating sequences of individual columns in the optic lobe with a telescope while recording from single T4 neurons, we find both mechanisms at work implemented in different sub-regions of the receptive field. This finding explains the high degree of directional selectivity found already in the fly’s primary motion-sensing neurons and marks an important step in our understanding of elementary motion detection.

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Perceived direction of deformation flow

10.1101/693762 ◽

2019 ◽

Author(s):

Takahiro Kawabe

Keyword(s):

Discrimination Performance ◽

Natural World ◽

Natural Image ◽

Global Motion ◽

Motion Direction ◽

Image Deformation ◽

Direction Discrimination ◽

Transparent Liquid ◽

Shearing Deformation ◽

Opposite Motion

AbstractIn everyday circumstances, human observers can easily discriminate the direction of transparent liquid flow. However, the mechanism of direction discrimination is not so straightforward. The present study focused on the flow of image deformation, which is closely related to the flow of transparent liquid in the natural world. To determine what image information is important in discriminating the direction of deformation flow, a natural image in a stimulus clip was deformed by using a deformation vector map that translated leftward or rightward. The task of the observers was to judge whether the transparent liquid in the clip flowed leftward or rightward. Manipulating the amplitude of deformation, we found that the discrimination performance improved with the amplitude. Interestingly, the observers’ performance was high overall only when shearing deformation was applied to the stimuli, while the observers reported an opposite-motion direction when only compressive deformation was applied. We computationally analyzed motion statistics of stimuli and found that the combination of mean and skewness of horizontal motion vectors reliably predicted the performance. The results indicate that human observers use global motion directions in order to determine the direction of deformation flow.

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The Effect of Temporal Phase on the Perception of Apparent Motion

Perception ◽

10.1068/v96l0806 ◽

1996 ◽

Vol 25 (1_suppl) ◽

pp. 68-68

Author(s):

H S Hock ◽

K Kogan ◽

N Lodes

Keyword(s):

Apparent Motion ◽

Motion Detection ◽

Discrimination Task ◽

Luminance Contrast ◽

Background Luminance ◽

Motion Direction ◽

Direction Discrimination ◽

Temporal Phase ◽

The Difference ◽

Perceived Speed

In classical apparent motion, a spot of light is presented in alternation such that the waveforms describing the varying luminance at each of two locations are 180° out of phase. However, when the luminance variation at each location is approximately sinusoidal, and the perceiver's task is to discriminate motion direction, the optimum temporal phase is 90° (van Santen and Sperling, 1984 Journal of the Optical Society of America A1 451 – 473). The results reported in this study suggest that the optimality of the 90° temporal phase may be specific to the direction-discrimination task. Our experiments were based on a new procedure for measuring classical apparent motion thresholds (Hock, Kogan, and Espinoza, 1996, paper presented at ARVO). Two horizontally displaced dots are presented simultaneously against a darker background. The luminance ( L1) of one dot is always greater than that of the other ( L2), and the luminance values for the dots are exchanged on successive frames. Whether motion or stationarity is perceived depends on the background-relative luminance contrast (BRLC): ( L1- L2) divided by the difference between the average [( L1+ L2)/2] and background luminance. We found in the current study that motion thresholds depend on the temporal phase of the luminance variation at each location (rather than temporal asynchrony); the greater the phase difference (from 41° to 180°) the less the BRLC required for motion perception. At suprathreshold BRLC values, the perceived speed of apparent motion decreases with increased differences in temporal phase. The results are discussed in terms of Reichardt-type motion detection models.

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Neural Timing Deficits Prevalent in Developmental Disorders, Aging, and Concussions Remediated Rapidly By Movement Discrimination Exercises

10.20944/preprints202105.0659.v1 ◽

2021 ◽

Author(s):

Teri Lawton ◽

John Shelley-Tremblay ◽

Ming-Xiong Huang

Keyword(s):

Working Memory ◽

Processing Speed ◽

Cognitive Skills ◽

Developmental Disorders ◽

Visual Motion ◽

Source Imaging ◽

Low Level ◽

Before And After ◽

High Level ◽

Movement Discrimination

(1) Background: Substantial evidence that neural timing deficits are prevalent in developmental disorders, aging, and concussions resulting from a mild Traumatic Brain Injury (mTBI) is presented. We show that if timing deficits are remediated using low-level movement discrimination training, then high-level cognitive skills, including reading, attention, processing speed, and working memory improve substantially. (2) Methods: Two case studies are presented using MEG source imaging on an adult dyslexic, and a healthy older adult observed before and after training on movement discrimination two times/week for 8 weeks for adult dyslexic. (3) Results: We found improvements in reading, attention, processing speed, and working memory on neuropsychological tests. Substantial MEG signal increases in visual Motion Networks (V1, V3, MT, MST), Attention Networks (ACC, dlPFC, vlPFC and precuneous/ PCC areas) and Memory Networks (dlPFC). (4) Conclusions: Improving neural timing deficits before cognitive exercises to improve specific cognitive skills provides a rapid and effective method to improve cognitive skills. Improving the timing and sensitivity of low-level dorsal pathways, improving feedforward and feedback pathways, is essential to improve high-level cognitive skills. This adaptive training with substantial feedback shows cognitive transfer to tasks not trained on, significantly improving a person’s quality of life rapidly and effectively.

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A Study of Moving Base Simulation Motion Cues Utilizing Washout Technique

Proceedings of the Human Factors Society Annual Meeting ◽

10.1177/154193127501900206 ◽

1975 ◽

Vol 19 (2) ◽

pp. 173-178

Author(s):

Mark Kirkpatrick ◽

Nicholas Shields ◽

Ronald Brye ◽

Frank L. Vinz

Keyword(s):

Constant Velocity ◽

Visual Cues ◽

Visual Motion ◽

General Purpose ◽

Psychophysical Method ◽

Human Observer ◽

Motion Direction ◽

Velocity Change ◽

Choice Procedure ◽

Moving Base

The present study was conducted to derive data on non-visual motion thresholds utilizing washout technique, and to develop specific threshold values for use as washout parameters. It describes the results of acceleration detection studies carried out using the NASA MSFC General Purpose Simulator which provides six degree-of-freedom cab motion. A series of experiments was performed to test the hypothesis that constant velocity visual cues might suppress non-visual deceleration sensitivity. The psychophysical method employed was the forced-choice procedure which theoretically yields a pure sensitivity measure. The MSFC General Purpose Simulator was programmed to provide velocity ramps in three axes – pitch, fore–aft translation, and vertical translation. Data were collected with and without a constant velocity visual input. Comparison of the current results with classical data suggested significantly greater sensitivity of the human observer to fore-aft accelerations than has generally been reported, sensitivity tending to depend on motion direction and sign of velocity change.

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