The Role of High Spatial Frequencies in Hemispheric Processing of Categorical and Coordinate Spatial Relations

2004 ◽  
Vol 16 (9) ◽  
pp. 1576-1582 ◽  
Author(s):  
Matia Okubo ◽  
Chikashi Michimata
Keyword(s):  
Visual Field ◽  
Spatial Frequency ◽  
Right Hemisphere ◽  
High Spatial Frequency ◽  
Spatial Relation ◽  
Spatial Relations ◽  
Right Visual Field ◽  
Spatial Frequencies ◽  
Low Pass ◽  
Categorical Task

Right-handed participants performed categorical and coordinate spatial relation tasks on stimuli presented either to the left visual field-right hemisphere (LVF-RH) or to the right visual field-left hemisphere (RVF-LH). The stimuli were either unfiltered or low-pass filtered (i.e., devoid of high spatial frequency content). Consistent with previous studies, the unfiltered condition produced a significant RVF-LH advantage for the categorical task and an LVF-RH advantage for the coordinate task. Low-pass filtering eliminated this Task × Visual Field interaction; thus, the RVF-LH advantage disappeared for the categorical task. The present results suggest that processing of high spatial frequency contributes to the left hemispheric advantage for categorical spatial processing.

Hemispheric Processing of Categorical and Coordinate Spatial Relations in the Absence of Low Spatial Frequencies

2002 ◽  
Vol 14 (2) ◽  
pp. 291-297 ◽  
Author(s):  
Matia Okubo ◽  
Chikashi Michimata
Keyword(s):  
Visual Field ◽  
Spatial Frequency ◽  
Right Hemisphere ◽  
Spatial Relation ◽  
Spatial Relations ◽  
Right Visual Field ◽  
Spatial Frequencies ◽  
Categorical Task ◽  
The Right ◽  
Coordinate Spatial Relations

Right-handed participants performed the categorical and coordinate spatial relation judgments on stimuli presented to either the left visual field—right hemisphere (LVF-RH) or the right visual field—left hemisphere (RVF-LH). The stimulus patterns were formulated either by bright dots or by contrast-balanced dots. When the stimuli were bright, an RVF-LH advantage was observed for the categorical task, whereas an LVF-RH advantage was observed for the coordinate task. When the stimuli were contrast balanced, the RVF-LH advantage was observed for the categorical task, but the LVF-RH advantage was eliminated for the coordinate task. Because the contrast-balanced dots are largely devoid of low spatial frequency content, these results suggest that processing of low spatial frequency is responsible for the right hemisphere advantage for the coordinate spatial processing.

Spatial-Frequency Discrimination, Brain Lateralisation, and Acute Intake of Alcohol

Perception ◽  
1998 ◽  
Vol 27 (6) ◽  
pp. 729-736 ◽  
Author(s):  
Reidulf G Watten ◽  
Svein Magnussen ◽  
Mark W Greenlee
Keyword(s):  
Visual Field ◽  
Spatial Frequency ◽  
Visual Information ◽  
Right Hemisphere ◽  
Frequency Discrimination ◽  
Right Visual Field ◽  
Double Blind ◽  
Spatial Frequencies ◽  
Balanced Placebo Design ◽  
Acute Intake

The effect of alcohol (breath-alcohol level of 0.1%) on perceptual discrimination of low (1.5 cycles deg−1) and high (8 cycles deg−1) spatial frequencies in the left and right visual field was measured in eighteen right-handed males, in a double-blind, balanced placebo design. Discrimination thresholds for briefly (180 ms) presented sinusoidal gratings were determined by two-alternative forced-choice judgments with four interleaving psychophysical staircases providing random trial-to-trial variation of reference spatial frequency and visual field, in addition to a random (±10%) jitter of reference spatial frequency. Alcohol produced overall higher discrimination thresholds but did not alter the visual-field balance: no main effect of visual field was observed, but in both placebo and alcohol conditions spatial frequency interacted with visual field in the direction predicted by the spatial-frequency hypothesis of hemispheric asymmetry in visual-information processing, with left-visual-field/right-hemisphere superiority in discrimination of low spatial frequencies and right-visual-field/left-hemisphere superiority in discrimination of high spatial frequencies.

Categorical and Metric Spatial Processes Distinguished by Task Demands and Practice

1999 ◽  
Vol 11 (2) ◽  
pp. 153-166 ◽  
Author(s):  
Marie T. Banich ◽  
Kara D. Federmeier
Keyword(s):  
Visual Field ◽  
Right Hemisphere ◽  
Receptive Fields ◽  
Spatial Relations ◽  
Task Demands ◽  
Spatial Processing ◽  
Right Visual Field ◽  
Metric Distance ◽  
The Right ◽  
Categorical Spatial Relations

In this study we examined Kosslyn's (1987) claim that the right hemisphere exhibits a relative superiority for processing metric spatial relations, whereas the left hemisphere exhibits a relative superiority for processing categorical spatial relations. In particular, we examined whether some failures to observe strong visual field (VF) advantages in previous studies might be due to practice effects that allowed individuals to process tasks in alternative manners (e.g., to process a metric task using a categorical strategy). We used two versions of a task previously employed by Hellige and Michimata (1989) in which individuals judge the metric (distance) or categorical (above/below) spatial relations between a bar and a dot. In one version, the position of the bar was held static. In another, the bar's position varied. This manipulation prevented participants from using the computer screen as a reference frame, forcing them to compute the spatial relationships on the basis of the relevant items only (i.e., the bar and the dot). In the latter, but not the former version of the task we obtained evidence supporting Kosslyn's hypothesis, namely, a significant right visual field (RVF) advantage for categorical spatial processing and a trend toward a left visual field (LVF) advantage for metric spatial processing. Furthermore, the pattern of results for trials on which information was presented centrally (CVF trials) was similar to that observed on RVF trials, whereas the pattern for trials in which identical information was presented in each visual field (BVF trials) was similar to that observed on LVF trials. Such a pattern is consistent with Kosslyn's suggestion that categorical processing is better suited for cells with small receptive fields and metric processing for cells with larger receptive fields.

The Role of High Spatial Frequencies in Face Perception

Perception ◽  
1983 ◽  
Vol 12 (2) ◽  
pp. 195-201 ◽  
Author(s):  
Adriana Fiorentini ◽  
Lamberto Maffei ◽  
Giulio Sandini
Keyword(s):  
Spatial Frequency ◽  
Face Perception ◽  
Energy Content ◽  
High Spatial Frequency ◽  
Face Width ◽  
Spatial Frequencies ◽  
Low Pass ◽  
High Pass ◽  
Spatial Frequency Domain

The relevance of low and high spatial-frequency information for the recognition of photographs of faces has been investigated by testing recognition of faces that have been either low-pass (LP) or high-pass (HP) filtered in the spatial-frequency domain. The highest resolvable spatial frequency was set at 15 cycles per face width (cycles fw−1). Recognition was much less accurate for images that contained only the low spatial frequencies (up to 5 cycles fw−1) than for images that contained only spatial frequencies higher than 5 cycles fw−1. For faces HP filtered above 8 cycles fw−1, recognition was almost as accurate as for faces LP filtered below 8 cycles fw−1, although the energy content of the latter greatly exceeded that of the former. These findings show that information conveyed by the higher spatial frequencies is not redundant. Rather, it is sufficient by itself to ensure recognition.

Spatial Processing and Hemispheric Asymmetry: Contributions of the Transient/Magnocellular Visual System

1998 ◽  
Vol 10 (4) ◽  
pp. 472-484 ◽  
Author(s):  
Elizabeth Cowin Roth ◽  
Joseph B. Hellige
Keyword(s):  
Visual Field ◽  
Visual Information ◽  
Hemispheric Asymmetry ◽  
Right Hemisphere ◽  
Spatial Task ◽  
Spatial Processing ◽  
Right Visual Field ◽  
Green Background ◽  
Categorical Task ◽  
The Right

Right-handed observers were presented with stimuli consisting of a line and two horizontally separated dots. A categorical spatial task required observers to indicate whether the dots were above or below the line, and a coordinate spatial task required observers to indicate whether the line could fit into the space between the two dots. For the coordinate task, reaction time was faster when the stimuli were presented to the left visual field (right hemisphere) than when the stimuli were presented to the right visual field (left hemisphere). The opposite hemispheric asymmetry was obtained for the categorical task. In addition, coordinate spatial processing took longer with stimuli presented on a red background than with stimuli presented on a green background. The opposite trend characterized categorical spatial processing. Because the color red attenuates processing in the transient/magnocellular visual pathway, these results suggest that coordinate spatial processing is more dependent on the transient/magnocellular pathway than is categorical spatial processing. However, manipulations of color condition had no effect on visual field (hemispheric) asymmetries, suggesting that the two hemispheres rely on the same visual information and on the same computational mechanisms as each other—although they do not always use that information with equal efficiency.

Categorical versus Coordinate Spatial Processing: Effects of Blurring and Hemispheric Asymmetry

1994 ◽  
Vol 6 (2) ◽  
pp. 156-164 ◽  
Author(s):  
Elizabeth L. Cowin ◽  
Joseph B. Hellige
Keyword(s):  
Visual Field ◽  
Visual Information ◽  
Right Hemisphere ◽  
Visual Fields ◽  
Spatial Processing ◽  
Right Visual Field ◽  
Horizontal Line ◽  
Significant Difference ◽  
Categorical Task ◽  
The Right

The present experiment examined the effects of dioptric blurring on the performance of two different spatial processing tasks using the same visual stimuli. One task (the above/below, categorical task) required subjects to indicate whether a dot was above or below a horizontal line. The other task (the coordinate, near/far task) required subjects to indicate whether the dot was within 3 mm of the line. For both tasks, the stimuli on each trial were presented to either the right visual field and left hemisphere (RVF/LH) or the left Visual field and right hemisphere (LVF/RH). For the above/below task, dioptric blurring consistently increased reaction time (RT) and did so equally on LVF/RH and RVF/LH trials. Furthermore, there was no significant difference between the two visual fields for either clear or blurred stimuli. For the near/far task, dioptric blurring had no consistent effect on either RT or error rate for either visual field. On an initial block of trials, however, there were significantly fewer errors on LVF/RH than on RVF/LH trials, with the LVF/RH advantage being independent of whether the stimuli were clear or blurred. This initial LVF/RH advantage disappeared quickly with practice, regardless of whether the stimuli were clear or blurred. This pattern of results suggests that for both cerebral hemispheres, somewhat different aspects of visual information are relevant for categorical versus coordinate spatial processing and that the right hemisphere is superior to the left for coordinate (but not categorical) spatial processing.

scholarly journals Persistent Hemispheric Differences in the Perceptual Selection of Spatial Frequencies

2014 ◽  
Vol 26 (9) ◽  
pp. 2021-2027 ◽  
Author(s):  
Elise A. Piazza ◽  
Michael A. Silver
Keyword(s):  
Spatial Frequency ◽  
Left Hemisphere ◽  
Hemispheric Asymmetry ◽  
Time Course ◽  
Right Hemisphere ◽  
High Spatial Frequency ◽  
Hemispheric Differences ◽  
Spatial Frequencies ◽  
The Right ◽  
Perceptual Selection

Previous research has shown that the right hemisphere processes low spatial frequencies more efficiently than the left hemisphere, which preferentially processes high spatial frequencies. These studies have typically measured RTs to single, briefly flashed gratings and/or have directed observers to attend to a particular spatial frequency immediately before making a judgment about a subsequently presented stimulus. Thus, it is unclear whether the hemispheres differ in perceptual selection from multiple spatial frequencies that are simultaneously present in the environment, without bias from selective attention. Moreover, the time course of hemispheric asymmetry in spatial frequency processing is unknown. We addressed both of these questions with binocular rivalry, a measure of perceptual selection from competing alternatives over time. Participants viewed a pair of rivalrous orthogonal gratings with different spatial frequencies, presented either to the left or right of central fixation, and continuously reported which grating they perceived. At the beginning of a trial, the low spatial frequency grating was perceptually selected more often when presented in the left hemifield (right hemisphere) than in the right hemifield (left hemisphere), whereas the high spatial frequency grating showed the opposite pattern of results. This hemispheric asymmetry in perceptual selection persisted for the entire 30-sec stimulus presentation, continuing long after stimulus onset. These results indicate stable differences in the resolution of ambiguity across spatial locations and demonstrate the importance of considering sustained differences in perceptual selection across space when characterizing conscious representations of complex scenes.

Evidence for the View That Temporospatial Integration in Vision is Temporally Anisotropic

Perception ◽  
1997 ◽  
Vol 26 (9) ◽  
pp. 1169-1180 ◽  
Author(s):  
Denis M Parker ◽  
J Roly Lishman ◽  
Jim Hughes
Keyword(s):  
Spatial Frequency ◽  
Spatial Information ◽  
High Spatial Frequency ◽  
Spatial Frequencies ◽  
Integration Mechanism ◽  
Low Pass ◽  
Degraded Image ◽  
Efficient Integration ◽  
Urban Scene ◽  
Frequency Sequence

In two experiments low-pass and high-pass spatially filtered versions of a base image were prepared and the effect of the order of delivery of sequences of filtered and base images investigated. A task that required subjects to discriminate 120 ms presentations of a full-bandwidth base image and degraded sequences that contained sets of three different spatially filtered versions, or mixtures of spatially filtered and full-bandwidth versions of the image, were used. Each set of images used in the degraded sequences was presented either so that within the 120 ms presentation window the spatial content swept from low to high spatial frequencies or from high to low. In experiment 1 twenty subjects discriminated between a base image and degraded sequences of an urban scene. Results showed both a significant overall effect of image order, with low-to-high spatial-frequency information delivery being mistaken more often for the full-bandwidth presentation than high-to-low, and that different sets of degraded image sequences varied significantly in the frequency with which they were mistaken for the full-bandwidth presentation. In experiment 2 a base and filtered versions of a human face were used in an identical task with twenty different subjects and a very similar pattern of significant results was obtained, although imposed on a lower overall error frequency than that obtained in experiment 1. It was concluded that the results of both experiments provide evidence for an anisotropic temporospatial integration mechanism in which availability of spatial information in a low-to-high spatial-frequency sequence results in more efficient integration than a high-to-low.

scholarly journals Contrast thresholds reveal different visual masking functions in humans and praying mantises

2017 ◽  
Author(s):  
Ghaith Tarawneh ◽  
Vivek Nityananda ◽  
Ronny Rosner ◽  
Steven Errington ◽  
William Herbert ◽  
...  
Keyword(s):  
Spatial Frequency ◽  
Motion Detection ◽  
Visual Masking ◽  
High Spatial Frequency ◽  
Visual Noise ◽  
Frequency Noise ◽  
Detection Systems ◽  
Spatial Frequencies ◽  
Summary Statement ◽  
Contrast Thresholds

AbstractRecently, we showed a novel property of the Hassenstein-Reichardt detector: namely, that insect motion detection can be masked by “invisible” noise, i.e. visual noise presented at spatial frequencies to which the animals do not respond when presented as a signal. While this study compared the effect of noise on human and insect motion perception, it used different ways of quantifying masking in two species. This was because the human studies measured contrast thresholds, which were too time-consuming to acquire in the insect given the large number of stimulus parameters examined. Here, we run longer experiments in which we obtained contrast thresholds at just two signal and two noise frequencies. We examine the increase in threshold produced by noise at either the same frequency as the signal, or a different frequency. We do this in both humans and praying mantises (Sphodromantis lineola), enabling us to compare these species directly in the same paradigm. Our results confirm our earlier finding: whereas in humans, visual noise masks much more effectively when presented at the signal spatial frequency, in insects, noise is roughly equivalently effective whether presented at the same frequency or a lower frequency. In both species, visual noise presented at a higher spatial frequency is a less effective mask.Summary StatementWe here show that despite having similar motion detection systems, insects and humans differ in the effect of low and high spatial frequency noise on their contrast thresholds.

scholarly journals Is Peripheral Motion Detection Affected by Myopia?

2021 ◽  
Vol 15 ◽  
Author(s):  
Junhan Wei ◽  
Deying Kong ◽  
Xi Yu ◽  
Lili Wei ◽  
Yue Xiong ◽  
...  
Keyword(s):  
Visual Field ◽  
Spatial Frequency ◽  
Motion Detection ◽  
High Speed ◽  
Detection Threshold ◽  
High Spatial Frequency ◽  
Spherical Equivalent ◽  
Detection Thresholds ◽  
Significant Difference ◽  
Motion Speed

PurposeThe current study was to investigate whether myopia affected peripheral motion detection and whether the potential effect interacted with spatial frequency, motion speed, or eccentricity.MethodsSeventeen young adults aged 22–26 years participated in the study. They were six low to medium myopes [spherical equivalent refractions −1.0 to −5.0 D (diopter)], five high myopes (<-5.5 D) and six emmetropes (+0.5 to −0.5 D). All myopes were corrected by self-prepared, habitual soft contact lenses. A four-alternative forced-choice task in which the subject was to determine the location of the phase-shifting Gabor from the four quadrants (superior, inferior, nasal, and temporal) of the visual field, was employed. The experiment was blocked by eccentricity (20° and 27°), spatial frequency (0.6, 1.2, 2.4, and 4.0 cycles per degree (c/d) for 20° eccentricity, and 0.6, 1.2, 2.0, and 3.2 c/d for 27° eccentricity), as well as the motion speed [2 and 6 degree per second (d/s)].ResultsMixed-model analysis of variances showed no significant difference in the thresholds of peripheral motion detection between three refractive groups at either 20° (F[2,14] = 0.145, p = 0.866) or 27° (F[2,14] = 0.475, p = 0.632). At 20°, lower motion detection thresholds were associated with higher myopia (p < 0.05) mostly for low spatial frequency and high-speed targets in the nasal and superior quadrants, and for high spatial frequency and high-speed targets in the temporal quadrant in myopic viewers. Whereas at 27°, no significant correlation was found between the spherical equivalent and the peripheral motion detection threshold under all conditions (all p > 0.1). Spatial frequency, speed, and quadrant of the visual field all showed significant effect on the peripheral motion detection threshold.ConclusionThere was no significant difference between the three refractive groups in peripheral motion detection. However, lower motion detection thresholds were associated with higher myopia, mostly for low spatial frequency targets, at 20° in myopic viewers.

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