Effect of target-background luminance contrast on binocular depth discrimination at photopic levels of illumination

A study was conducted of the effects of exposure to combinations of low ambient temperatures (70°, 20°, 0°, −20°, −40°F) and wind (3, 10, 20, 30 mph) upon binocular depth discrimination at three viewing distances (20, 40, 60 ft.). 60 groups of 8 Ss each were randomly assigned to one of 60 possible treatment combinations in a factorial design, and binocularly performed depth equality settings using the Howard-Dolman task. The results indicated significant main effects for temperature, wind, and viewing distance, as well as a significant T × W interaction, which occurred for a very brief exposure duration of 1 min. The results are interpreted in light of previous findings for binocular viewing over natural terrain, supporting the notion of two types of stereoscopic threshold, i.e., true stereopsis (ηt) and relative sensitivity in commonplace viewing (ηR).

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Associations Between Binocular Depth Perception and Performance Gains in Laparoscopic Skill Acquisition

Frontiers in Human Neuroscience ◽

10.3389/fnhum.2021.675700 ◽

2021 ◽

Vol 15 ◽

Author(s):

Adamantini Hatzipanayioti ◽

Sebastian Bodenstedt ◽

Felix von Bechtolsheim ◽

Isabel Funke ◽

Florian Oehme ◽

...

Keyword(s):

Perceptual Learning ◽

Skill Acquisition ◽

Depth Perception ◽

Motor Coordination ◽

Laparoscopic Skill ◽

Laparoscopic Skills ◽

Depth Discrimination ◽

Visual Motor ◽

Performance Gains ◽

Binocular Depth

The ability to perceive differences in depth is important in many daily life situations. It is also of relevance in laparoscopic surgical procedures that require the extrapolation of three-dimensional visual information from two-dimensional planar images. Besides visual-motor coordination, laparoscopic skills and binocular depth perception are demanding visual tasks for which learning is important. This study explored potential relations between binocular depth perception and individual variations in performance gains during laparoscopic skill acquisition in medical students naïve of such procedures. Individual differences in perceptual learning of binocular depth discrimination when performing a random dot stereogram (RDS) task were measured as variations in the slope changes of the logistic disparity psychometric curves from the first to the last blocks of the experiment. The results showed that not only did the individuals differ in their depth discrimination; the extent with which this performance changed across blocks also differed substantially between individuals. Of note, individual differences in perceptual learning of depth discrimination are associated with performance gains from laparoscopic skill training, both with respect to movement speed and an efficiency score that considered both speed and precision. These results indicate that learning-related benefits for enhancing demanding visual processes are, in part, shared between these two tasks. Future studies that include a broader selection of task-varying monocular and binocular cues as well as visual-motor coordination are needed to further investigate potential mechanistic relations between depth perceptual learning and laparoscopic skill acquisition. A deeper understanding of these mechanisms would be important for applied research that aims at designing behavioral interventions for enhancing technology-assisted laparoscopic skills.

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Binocular depth discrimination depends on orientation

Perception & Psychophysics ◽

10.3758/bf03199441 ◽

1976 ◽

Vol 20 (2) ◽

pp. 113-118 ◽

Cited By ~ 12

Author(s):

Randolph Blake ◽

John M. Camisa ◽

Dianne N. Antoinetti

Keyword(s):

Depth Discrimination ◽

Binocular Depth

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Stereoscopic mechanisms: binocular responses of the striate cells of cats to moving light and dark bars

Proceedings of the Royal Society of London Series B Biological Sciences ◽

10.1098/rspb.1986.0084 ◽

1986 ◽

Vol 229 (1256) ◽

pp. 227-256 ◽

Cited By ~ 21

Keyword(s):

Receptive Fields ◽

Neural Mechanisms ◽

Stimulus Contrast ◽

Depth Discrimination ◽

Response Profile ◽

Binocular Facilitation ◽

Receptive Field Disparity ◽

Response Profiles ◽

Preferred Stimulus ◽

Binocular Depth

New knowledge concerning the internal structure and response properties of the receptive fields of striate cells calls for a fresh appraisal of their binocular interactions in the interest of a better understanding of the neural mechanisms underlying binocular depth discrimination. Binocular position-disparity response profiles were recorded from 71 simple and B-cells in response to moving light and dark bars. Predominantly excitatory (PE) cells ( N = 48) had disparity response profiles that were spatially closely similar to their respective monocular responses. In addition, the centrally located excitatory subregions were flanked on one or both sides by non-specific inhibitory regions, PE cells with a preferred stimulus orientation within 30° of the vertical ( N = 17) showed binocular facilitations with maximal values that were always more than twice (mean 3.3) the sum of the two monocular responses to the same stimuli and generally greater than the facilitations shown by cells with orientations more than 30° from the vertical ( N = 29; mean 2.2 times the sum of the respective monocular responses). The strength of the binocular facilitation depended on the stimulus contrast, the facilitation decreasing with increasing contrast. The receptive-field disparity distribution of the 31 PE cells capable of making significant horizontal disparity discriminations has standard deviations of 0.37° and 0.40°, respectively. Predominantly inhibitory cells (PI) ( N = 23) showed two basic types of disparity response profile: symmetric ( N = 17) and asymmetric ( N = 6). Uncertainty regarding the precise location of the binocular fixation point in the anaesthetized and paralysed preparation made it difficult to categorize PI cells adequately.

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Correlated structure of neuronal firing in macaque visual cortex limits information for binocular depth discrimination

Journal of Neurophysiology ◽

10.1152/jn.00667.2020 ◽

2021 ◽

Author(s):

Jackson Earle Tulonen Smith ◽

Andrew J Parker

Keyword(s):

Theoretical Work ◽

Temporal Scale ◽

Neuronal Firing ◽

Brain Areas ◽

Cortical Areas ◽

Depth Discrimination ◽

Binocular Stereo ◽

Integrative Processing ◽

Visual Cortical ◽

Binocular Depth

Variability in cortical neural activity potentially limits sensory discriminations. Theoretical work shows that information required to discriminate two similar stimuli is limited by the correlation structure of cortical variability. We investigated these information-limiting correlations by recording simultaneously from visual cortical areas V1 and V4 in macaque monkeys, performing a binocular, stereo-depth discrimination task. Within both areas, noise correlations on a rapid temporal scale (20-30ms) were stronger for neuron-pairs with similar selectivity for binocular depth, meaning that these correlations potentially limit information for making the discrimination. Between-area correlations (V1 to V4) were different, being weaker for neuron pairs with similar tuning, and having a slower temporal scale (100+ms). Fluctuations in these information-limiting correlations just prior to the detection event were associated with changes in behavioral accuracy. Although these correlations limit the recovery of information about sensory targets, their impact may be curtailed by integrative processing of signals across multiple brain areas.

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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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Effects of Target Separation and Distance on Commonplace Binocular Depth Discrimination

Journal of the Optical Society of America ◽

10.1364/josa.46.000122 ◽

1956 ◽

Vol 46 (2) ◽

pp. 122 ◽

Cited By ~ 5

Author(s):

Warren H. Teichner ◽

John L. Kobrick ◽

E. Ralph Dusek

Keyword(s):

Depth Discrimination ◽

Binocular Depth

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