Previous experiments demonstrate a normal decline in unconditioned responding in rats with perirhinal cortex lesions but attenuated performance on spontaneous object recognition (SOR), a finding supporting the assertion that distinct systems support these phenomena. This finding informs on the nature of these two fundamental forms of learning and may be ...

CONTEXT: Posterior shoulder tightness has been associated with altered shoulder range of motion (ROM) and several pathologic entities among baseball players. This tightness is hypothesized to be the result of the cumulative stress placed on the posterior shoulder during the deceleration phase of the throwing motion. The role of the ...

BACKGROUND: Missing adenomas and the inability to accurately differentiate between polyp histology remain the main limitations of standard-definition white-light (SD-WL) colonoscopy. OBJECTIVE: To compare the adenoma detection rates of SD-WL with those of high-definition white-light (HD-WL) and narrow-band imaging (NBI) as well as the accuracy of predicting polyp histology. DESIGN: ...

In mammals, the nocturnal melatonin signal is well established as a key hormonal indicator of seasonal changes in day-length, providing the brain with an internal representation of the external photoperiod. The pars tuberalis (PT) of the pituitary gland is the major site of expression of the G-coupled receptor MT1 in ...

We propose a polarizing color filter based on a one-dimensional subwavelength metal-dielectric grating combining the functions of a polarizer and a color filter. The proposed device consists of three parts: a substrate, a dielectric grating, and a metal grating. The effects of the dielectric grating and the metal grating are ...

Review of basic principles and recent developments in the area of stimuli responsive polymeric capsules and nanoshells formed via layer-by-layer (LbL) is presented. The most essential attributes of the LbL approach are multifunctionality and responsiveness to a multitude of stimuli. The stimuli can be logically divided into three categories: physical ...

Aquatic habitats are rich in polarized patterns that could provide valuable information about the environment to an animal with a visual system sensitive to polarization of light. Both cephalopods and fishes have been shown to behaviourally respond to polarized light cues, suggesting that polarization sensitivity (PS) may play a role ...

Prominent in the sky, but not visible to humans, is a pattern of polarized skylight formed around both the Sun and the Moon. Dung beetles are, at present, the only animal group known to use the much dimmer polarization pattern formed around the Moon as a compass cue for maintaining ...

Many animals rely on a sun compass for spatial orientation and long-range navigation. In addition to the Sun, insects also exploit the polarization pattern and chromatic gradient of the sky for estimating navigational directions. Analysis of polarization-vision pathways in locusts and crickets has shed first light on brain areas involved ...

Purpose. To assess the effect on visual acuity of compensating fixation instability by controlling retinal image motion in people with macular disease. Methods. Ten patients with macular disease participated in this study. Crowded and noncrowded visual acuity were measured using an eye tracking system to compensate for fixation instability. Four ...

The inverse opal hydrogel heterostructure (polyacrylamide (PAAm) (left side)-polyacrylic acid (PAA)/PAAm interpenetrating polymer network (IPN) (right side) is created by colloidal crystal templating. The two parts, PAAm and IPN, appear different structural colors due to the varied lattice constants and solvent response behaviors. The IPN part keeps red color and ...

Individuals with autism often show a fragmented way of perceiving their environment, suggesting a disorder of information integration, possibly due to disrupted communication between brain areas. We investigated thirteen individuals with high-functioning autism (HFA) and thirteen healthy controls using the metastable motion quartet, a stimulus consisting of two dots alternately ...

Although perceptual decision making activates a network of brain areas involved in sensory, integrative, and motor functions, circuit activity can clearly be modulated by factors beyond the stimulus. Of particular interest is to understand how the network is modulated by top-down factors such as attention. Here, we demonstrate in a ...

Human gaze is a critical social cue that can reveal intentions and dispositions of others. The right posterior superior temporal sulcus (pSTS) is thought to be critically involved in processing eye gaze information. We combined diffusion tensor imaging (DTI) and functional magnetic resonance imaging (fMRI) to identify direct neural connections ...

To investigate the surface integrity of solvent-challenged ormocer-matrix composites, photoactivated by different light exposure modes, through surface-hardness measurements at different periods of time; and to compare such behavior with dimethacrylate-based materials. One hundred percent ormocer-based matrix (experimental ormocer (ORM)), a commercial mixed dimethacrylate-ormocer-based matrix (Admira (ADR)) and two commercial dimethacrylate-based ...

A highly familiar type of movement occurs whenever a person walks towards you. In the present study, we investigated whether this type of motion has an effect on face processing. We took a range of different 3D head models and placed them on a single, identical 3D body model. The ...

Can linguistic semantics affect neural processing in feature-specific visual regions? Specifically, when we hear a sentence describing a situation that includes motion, do we engage neural processes that are part of the visual perception of motion? How about if a motion verb was used figuratively, not literally? We used fMRI ...

In representational momentum (RM), the final position of a moving target is mislocalized in the direction of motion. Here, the effect of a concurrent sound on visual RM was demonstrated. A visual stimulus moved horizontally and disappeared at unpredictable positions. A complex tone without any motion cues was presented continuously ...

The magnitude of the association between developmental dyslexia (DD) and motion sensitivity is evaluated in 35 studies, which investigated coherence motion perception in DD. A first analysis is conducted on the differences between DD groups and age-matched control (C) groups. In a second analysis, the relationship between motion coherence threshold ...

Across humans' evolutionary history, detecting animate entities in the visual field (such as prey and predators) has been critical for survival. One of the defining features of animals is their motion-self-propelled and self-directed. Does such animate motion capture visual attention? To answer this question, we compared the time to detect ...

Accuracy in estimating an object's global motion over time is not only affected by the noise in visual motion information but also by the spatial limitation of the local motion analyzers (aperture problem). Perceptual and oculomotor data demonstrate that during the initial stages of the motion information processing, 1D motion ...

The magnocellular (M) pathway hypothesis proposes that impaired visual motion perception observed in individuals with Autism Spectrum Disorders (ASD) might be mediated by atypical functioning of the subcortical M pathway, as this pathway provides the bulk of visual input to cortical motion detectors. To test this hypothesis, we measured luminance ...

The onset of motion in an otherwise continuous sound elicits a prominent auditory evoked potential, the so-called motion onset response (MOR). The MOR has recently been shown to be modulated by stimulus-dependent factors, such as velocity, while the possible role of task-dependent factors has remained unclear. Here, the effect of ...

Humans use smooth pursuit eye movements to track moving objects of interest. In order to track an object accurately, motion signals from the target have to be integrated and segmented from motion signals in the visual context. Most studies on pursuit eye movements used small visual targets against a featureless ...

This study investigated the effect of temporal frequency and modulation depth on reaction times for discriminating the direction of first-order (luminance-defined) and second-order (contrast-defined) motion, equated for visibility using equal multiples of direction-discrimination threshold. Results showed that reaction times were heavily influenced by temporal frequency, especially in the case of ...

We report blue fluorescent organic light-emitting devices (OLED) by solution process utilizing a blue emitting small molecule, 2,7-bis[(9-ethyl-9H-carbazol-3-yl)ethenyl]-9,9-bis(4-n-octyloxyphenyl)-9H-fluorene (CB), which has good solubility in common organic solvent. The peak positions of absorption and emission spectra of a new fluorene-based molecule in tetrahydrofuran solution were observed at 399 and 439 nm, ...

Spatiotemporal context in sensory stimulus has profound effects on neural responses and perception, and it sometimes affects task difficulty. Recently reported experimental data suggest that human detection sensitivity to motion in a target stimulus can be enhanced by adding a slow surrounding motion in an orthogonal direction, even though the ...

Multisensory interactions between haptics and vision remain poorly understood. Previous studies have shown that shapes, such as letters of the alphabet, when drawn on the skin, are differently perceived dependent upon which body part is stimulated and on how the stimulated body part, such as the hand, is positioned. Another ...

Motion boundaries (local changes in visual motion direction) arise naturally when objects move relative to an observer. In human visual cortex, neuroimaging studies have identified a region (the kinetic occipital area [KO]) that responds more strongly to motion-boundary stimuli than to transparent-motion stimuli. However, some functional magnetic resonance imaging (fMRI) ...

Audiovisual synchrony enables integration of dynamic visual and auditory signals into a more robust and reliable multisensory percept. In this fMRI study, we investigated the neural mechanisms by which audiovisual synchrony facilitates shape and motion discrimination under degraded visual conditions. Subjects were presented with visual patterns that were rotated by ...

Motion-in-depth causes changes in the size of retinal images in addition to producing optic flow patterns. A previous psychophysical study showed that human subjects can perceive expansion motion in texture stimuli that exhibit increases in the scale of image elements but no consistent optic flow pattern. The neural mechanisms by ...

Two experiments examined extinction to stimuli presented either with contracting or expanding motion. Experiment 1 used solid shapes which either increased or decreased in size rapidly, consistent with looming motion. Experiment 2 employed random dots so that stimulus size was not confounded with type of motion. In both experiments extinction ...

Based on the principle of efficient coding, we present a theoretical framework for how to categorize the basic types of changes that can occur in a spatio-temporal signal. First, theoretical results for the problem of estimating multiple transparent motions are reviewed. Then, confidence measures for the presence of multiple motions ...

Humans are very sensitive to the presence of other living persons or animals in their surrounding. Human actions can readily be perceived, even in a noisy environment. We recently demonstrated that biological motion, which schematically represents human motion, influences smooth pursuit eye movements during the initiation period (Orban de Xivry, ...

Sensitivity to visual motion is a fundamental property of neurons in the visual cortex and has received wide attention in terms of mathematical models. A key feature of many popular models for cortical motion sensors is the use of pairs of functions that are related by a 90 degrees phase ...

Age is known to affect sensitivity to retinal motion. However, little is known about how age might affect sensitivity to motion during pursuit. We therefore investigated direction discrimination and speed discrimination when moving stimuli were either fixated or pursued. Our experiments showed: (1) age influences direction discrimination at slow speeds ...

A highly important question in visual neuroscience is to identify where in the visual system information from different processing channels is integrated to form the complex scenery we perceive. A common view to this question is that information is processed hierarchically because small and selective receptive fields in lower visual ...

Single-cell recording studies have provided vision scientists with a detailed understanding of motion processing at the neuronal level in non-human primates. However, despite the development of brain imaging techniques, it is not known to what extent the response characteristics of motion-sensitive neurons in monkey brain mirror those of human motion-sensitive ...

It is unknown whether the rodent visual system can perceive biological motion, an ability present in primates, cats, and several bird species. Using a water-maze visual discrimination task, we find that rats can be trained to distinguish between left- and rightward motion of abstract point-light displays of walking humans. However, ...

Because the human visual system is continually being bombarded with inputs, it is necessary to have effective mechanisms for filtering out irrelevant information. This is partly achieved by the allocation of attention, allowing the visual system to process relevant input while blocking out irrelevant input. What is the physiological substrate ...

In an influential study, R. J. Bootsma and P. C. W. van Wieringen (1990) argued that 2 of their 5 participants used visual information continuously during the attacking forehand drive in table tennis, its brief duration vis-à-vis the visuomotor delay notwithstanding. The authors repeated Bootsma and van Wieringen's experiment and ...

There is behavioral evidence of increased spontaneous recruitment of visual attention to ancestral evolved categories, such as animals, compared with expertise-derived categories, such as a computer. In order to investigate the association between visual perception and spontaneous visual attention, a study was performed to determine if brain activation whilst viewing ...

A version of the line motion illusion (LMI) occurs when one of two adjacent surfaces changes in luminance; a new surface is perceived sliding in front of the initially presented surface. Previous research has implicated high-level mechanisms that can create or modulate LMI motion via feedback to lower-level motion detectors. ...

Human vision remains perceptually stable even though retinal inputs change rapidly with each eye movement. Although the neural basis of visual stability remains unknown, a recent psychophysical study pointed to the existence of visual feature-representations anchored in environmental rather than retinal coordinates (e.g., "spatiotopic" receptive fields; Melcher and Morrone, 2003). ...

Recent studies have shown that many neurons in the primate dorsal medial superior temporal area (MSTd) show spatial tuning during inertial motion and that these responses are vestibular in origin. Given their well-studied role in processing visual self-motion cues (i.e., optic flow), these neurons may be involved in the integration ...

In the visual system of Drosophila, photoreceptors R1-R6 relay achromatic brightness information to five parallel pathways. Two of them, the lamina monopolar cells L1 and L2, represent the major input lines to the motion detection circuitry. We devised a new method for optical recording of visually evoked changes in intracellular ...

Brain activity was recorded while participants engaged in a difficult visual search task for a target defined by the spatial configuration of its component elements. The search displays were segmented by time (a preview then a search display), by motion, or were unsegmented. A preparatory network showed activity to the ...

To investigate form-related activity in motion-sensitive cortical areas, we recorded cell responses to animate implied motion in macaque middle temporal (MT) and medial superior temporal (MST) cortex and investigated these areas using fMRI in humans. In the single-cell studies, we compared responses with static images of human or monkey figures ...

Although it is well documented that the ability to perceive biological motion is mediated by the lateral temporal cortex, whether and when neural activity in this brain region is modulated by attention is unknown. In particular, it is unclear whether the processing of biological motion requires attention or whether such ...

Adult observers can quickly identify specific actions performed by an invisible actor from the points of lights attached to the actor's head and major joints. Infants are also sensitive to biological motion and prefer to see it depicted by a dynamic point-light display. In detecting biological motion such as whole ...