orientation

..These findings provide evidence that view-based strategies to reorient by geometry could be used by animals...

..These results demonstrate that it is necessary to use measures that take response biases into account in order to fully understand the holistic nature of face processing...

..b>Orientation columns in visual cortex are perhaps the best known example of such a functional organization in the brain...

..The time course of object detection and object categorization can be selectively manipulated. They are not intrinsically linked. As soon as you know an object is there, you do not necessarily know what it is...

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..Scalp EEG (53 channels) was recorded in 15 subjects performing an orientation decision task with pictures of faces, words, and cars presented upright or inverted...

..owing to the low spatial resolution of conventional human neuroimaging techniques compared to the size of orientation columns in visual cortex...

..We manipulated low-level properties, such as element orientation and local motion, while incorporating higher-level properties, such as object complexity and identity, and ..

..cortex of primates and carnivores is organized into columns of neurons with similar preferences for stimulus orientation, but the developmental origin and function of this organization are still matters of debate...

..This study provides evidence that links single-unit activity to spatial perception mediated by vestibular signals, and supports the idea that the role of MSTd in self-motion perception extends beyond optic flow processing...

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..neglected in mice perhaps because of their poor spatial acuity and the lack of columnar organization such as orientation maps...

Neuronal orientation selectivity has been shown in animal models to require corticocortical network cooperation and to be dependent on the presence of GABAergic inhibition...

..These findings are inconsistent with the claim that holistic processing, as indexed by the composite face effect, significantly influences accuracy in a face-identification task...

..Our results suggest that in normal viewing, figural aftereffects may strongly influence form perception and could provide a novel method for probing properties of human face perception...

..These findings suggest that distinct brain areas are involved in redirecting attention based upon sensory events (bottom-up, exogenous shifts) and based upon cognitive expectations (top-down, endogenous shifts)...

..Identifying the neuronal mechanisms and functional roles of each type of representation, and of their interactions, promises to provide a framework for investigation of the organization of human memory more generally...

..of object motion in external space, the brain must combine retinal motion signals and information about the orientation of the eyes in space...

..such activity encompasses a set of dynamically switching cortical states, many of which correspond closely to orientation maps...

..Grids of neighbouring cells share a common orientation and spacing, but their vertex locations (their phases) differ...

The origin of orientation selectivity in the responses of simple cells in cat visual cortex serves as a model problem for understanding cortical circuitry and computation...

..A final experiment with forty 7-year-old children suggested that children like adults showed independence between the three networks under some conditions...

..random), while still preserving pairwise relationships between the target and flankers. Orientation discrimination and contrast detection of the central Gabor were measured...

..principles of visual cortical organization is that neurons form a "map" in which neighboring cells have similar orientation preferences...

..These findings show that perceptual cue integration occurs in nonhuman primates and identify a population of neurons that may form its neural basis...

..originating from one of the "form-processing" extrastriate cortical areas, area 21a (A21a), to orientation selectivity of single neurons in the ipsilateral area 17 (A17)...

..We concentrate on perhaps the best studied test case, namely orientation or tilt, which gives rise to the notorious tilt illusion and the adaptation tilt after-effect...

..Moreover, access to both allocentric and egocentric streams of spatial information may enable the posterior PHG to construct a global and comprehensive representation of spatial environments...

..When adapting and test stimuli shared the same orientation, aftereffects were similar for upright and inverted faces...

..The findings provide a new view, demonstrating that the maintenance of attention and shifting of attention differ in their relationship to the oculomotor system...

..Here, we show that the antennae are necessary for proper time-compensated Sun compass orientation in migratory monarch butterflies, that antennal clocks exist in monarchs, and that they likely provide the ..

..Our data show that even in trained adult pigeons, olfactory cues are needed for homing from unfamiliar locations and that the lack of magnetic information does not affect navigational abilities of experienced adult homing pigeons...

..These findings show that odors, rather than providing navigational information, activate a nonolfactory path integration system...

..The pictures presented conspecific faces with open or closed eyes in an upright or inverted orientation in a frame...

..Spatial interactions are strong at upright, but not inverted orientation. Recent evidence indicated spatial interactions root in the low spatial frequencies (LSF) of face stimulus...

..We further tested the GABA hypothesis by examining the relationship between visual cortical GABA levels and orientation-specific surround suppression (OSSS), a behavioral measure of visual inhibition thought to be dependent on ..

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..and haptic information optimally, but that one or the other sense prevails: touch for size and vision for orientation discrimination...

..Effects of imagery and perception were location and orientation specific, accumulated in strength over time, and survived an intervening visual task lasting several seconds ..

Spatial orientation is critical for many behaviors. Intrinsic to the oriented state is the knowledge of past, present, and future spatial location relative to one or more landmarks...

..In summary, we have demonstrated that the temporal dynamics of reversal with biological motion are similar to other forms of ambiguous SFM. We conclude that perceptual switching with biological motion is a robust bistable phenomenon...

..We quantified computationally the dependency of MEG and EEG on the source orientation using a forward model with realistic tissue boundaries...

..In rectangular lattices, distance ratio and global orientation of rows and columns were manipulated...

..In both experiments, low-span participants performed poorly when task switching from antisaccade to prosaccade blocks. The findings support a controlled-attention view of WM capacity...

..The spatial selectivity of cross-orientation suppression (XOR) has been described, so for this paper we investigated the temporal properties of XOR...

..we chose a planar stimulus and examined the relation between the neural responses and the simulated 3D orientation of the plane defined by motion cues...

..The CP-in-noise signature phenomenon was then used to show that configural processing survives image plane rotations of 45 degrees-90 degrees...

..Rather than signaling object image motion on the retina, they represent object motion in world-centered coordinates. This representation may simplify the coordination of object-directed action and ego motion-invariant visual perception...

..perceptual distortions are generated by dynamic alteration of connection efficacy within a network linking cortical areas of similar orientation specificity, consistent with established anatomical and physiological results.

..We argue that even early memory representations for pointing movements are influenced by visual information in the surrounding visual field...

..We investigated whether the perception of edge orientation, a fundamental visual feature, can be decoded from human brain activity measured with functional magnetic ..

Results of earlier spatial-orientation studies focusing on the sense of verticality have emphasized an intriguing paradox...

..measuring the fMRI response to sequential pairs of sinusoidal gratings that had either the same or orthogonal orientation. The adaptation hypothesis predicts that brain areas with orientation-selective neurons should show a more ..

Task-related characteristics of gait and segment orientation during natural locomotion along a curved path have been described in order to gain insight into the neural organization of walking...

..We conclude that eye movements are driven by the degree of match, along various dimensions that go beyond simple visual form, between a word and the mental representations of objects in the concurrent visual field...

..wherein the only factor dichotomizing performance was the neural complexity required to discriminate grating orientation. The ability of persons with autism was found to be superior for identifying the orientation of simple, ..

..The bee's perception of distance flown is therefore not absolute, but scene-dependent. These findings raise important and interesting questions about how these animals navigate reliably...

..analytical techniques enabled by the high-resolution GPS data (track efficiency, virtual vanishing bearings, orientation threshold), we localised the preview effect to the first 1000 m of the journey...

..Posture and view effects on body parts representations are discussed with respect to proprioception, handedness, visual familiarity and the influence of anatomical joint constraints on motor imagery...

..We predicted that its orientation to prevailing currents and the arrangement of its siphons would induce passive flow due to dynamic pressure at ..

..From these results, we conclude that masking derives its effectiveness, at least partly, from disrupting reentrant processing, thereby interfering with the neural mechanisms of figure-ground segmentation and visual awareness itself...

..insensitive to faint test patterns that resemble the pre-exposed pattern (such as gratings of the same orientation), and we require more contrast to detect them...

..The effects last for up to 3 s without diminution and are not affected by changes in color, polarity, or contrast. These findings are discussed as they relate to spatial attention, object perception, and memory...

..Hand presence affected attentional prioritization of space, not the shifting of attention...

..The results argue against a spreading trace of attention that encompasses the whole line...

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..Overall, the two-stage-processing hypothesis gave the best account, with respect both to choice probabilities and to observed mean RTs and mean RT patterns within a choice pair...

..In that way, we propose that participants could automatically simulate the typical size as soon as they perceived the drawings of objects with homegenous sizes...

..The results suggest that exogenous but not endogenous attention operates in perceived 3-D space...

..The specific nature of their learning deficit is consistent with reports of physiological and anatomical differences for individuals with dyslexia in frontal and cerebellar structures...

..This result suggests a relatively late (re)activation in visual areas associated with the processing of stimuli that had not been cued in advance...

..To evaluate the contribution of information about orientation from motion smear, thresholds for orientation discrimination were measured using parallel lines with the same ..

..These findings establish a new laboratory measure of a form of distractibility common to everyday life and highlight load as an important determinant of such distractibility...

..The results of two experiments support this account...

Stimuli moving in slightly different directions trace trajectories that differ slightly in orientation. These different 'speed lines', in principle, could generate responses in orientation mechanisms, and such responses could determine ..

..This is an encouraging outcome because it suggests that the physical layout of the workspace can be used to predict MTs for obstacle avoiding movements, an accomplishment that fits with the spirit of Fitts' Law...

..These results provide further support for earlier behavioral and neuroimaging studies indicating that automatic orienting of attention by arrow cues and gaze cues are based on different neural mechanisms...

..These results might help to characterize the human mirror neuron system and reveal how joint attention tunes early perceptual processes toward action prediction...

..Finally, both ventral and dorsal regions were modulated during reorienting but significantly only by reorienting after voluntary shifts, suggesting the importance of a mismatch between expectation and sensory input...

..Strategic self-organization develops until ages 16 to 17 years. Recognition memory did not appear to develop over this age range. Implications for prefrontal cortex organization by level of processing are discussed...

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..The timing of attentional cueing affected feature pairing reports as much as the timing of the features themselves...

..We conclude that the amount of top-down information provided by predictive cues influences the neural correlates of reorienting of visuospatial attention by modulating activation of a right fronto-parietal attentional network...

..Results indicated that nonoverlapping feedforward signals by primes and targets traverse the visuomotor system in a rapid chase, controlling associated motor responses in strict sequence...

..The results suggest that the presentation of an accessory stimulus facilitates response activation processes because of the participants' enhanced level of preparation for stimulus processing...

..Overall, the results suggest that the time course of color cueing is not inherently different from that of location cueing once its main disadvantages are removed...

..Simpler memory-based accounts that do not take into account the context in which a person is embedded cannot adequately account for the results...

..In the discussion, we describe the implications and limitations of these data for theories of warning effects and potential avenues for future research...

..The left IFG was correlated with memory retrieval of the cued representation for conjunction detection, and the right posterior PCu was associated with maintenance and memory retrieval among competing stimuli...

..This pattern of results implies that both the left and right PPC are directly involved in the interaction between attention and smooth pursuit preparation...

..Briefly, target-mask similarity determines how motor preparation is accumulated during the prime-mask sequence...

..More broadly, the nature of the information being stored--not the nature of the operations performed on this information--may determine which subsystem stores the information...

..e., offline updating). These results support M. Amorim, S. Glasauer, K. Corpinot, and A. Berthoz's (1997) 2-system model of spatial updating that includes both online and offline updating...

..Thus, at least under certain circumstances, medial rostral PFC appears to support attention toward the external environment, facilitating performance in situations that do not require extensive processing of experimental stimuli...

..e., 3 short and 3 long durations). The compatibility effect between hand and duration was replicated, but followed a rectangular function of the duration. The shape of this function is discussed in relation to the specific task demands...

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..If these interfering representations are eliminated, the performance is again improved. The implications of these findings for general human spatial cognition are discussed...

..Conflict resolution was impaired only in AD. Orienting remained unchanged across groups. These findings provide evidence of different life span developmental and clinical trajectories for each attentional network...

..Overall, our findings show that a Simon-like effect can only be observed under conditions of explicit change detection, likely because a shift of attention towards the change location has occurred...

..In addition, the studies will demonstrate that perceptual processing abilities must be considered and either controlled for or manipulated in cognitive aging research. ..

..These guidelines will lead to development of products and environments that allow elderly adults to remain more independent and to engage safely in more activities in their daily lives. ..

..Postdoctoral trainees will have at least two mentors from the training faculty and will join a rich environment for postdoctoral investigations in the Department of Psychology. ..

..The results from these studies will be directly applicable to clinical situations concerning the functional outcomes of cochlear implants in young children. ..

..Such a development should have wide appeal and will greatly advance our ability to dissect functional circuits with fMRI. ..

..I-m), and testing time course of mGluR modulation of transmission in s. I-m. Understanding these mechanisms may assist in development of pharmacological treatments for Alzheimer's disease. ..

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..Thus, the proposed research will provide essential information for understanding conditions that involve deficits in the control of gaze. ..

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..U., which focuses on modeling operant tasks used in experimental studies of drug self-administration phenomena, in work supported by a supplement to a previous grant from NIDA. ..

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..Understanding of the cellular effects of acetylcholine involved in these processes could allow targeting of specific receptor effects in the treatment of disorders. ..

..This empirical work will lay the essential groundwork for development of a formal model linking linguistic and non-linguistic representations of space. ..

..Research could guide combined use of drugs influencing GABAb and ACh receptors. ..

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..Together these studies will assist in understanding the dynamic role of entorhinal cortex in representing environmental stimuli for active maintenance and encoding into episodic memory. ..

..Findings may also lead to ways of improving spatial abilities in the general population. ..

..I-m), and testing time course of mGluR modulation of transmission in s. I-m. Understanding these mechanisms may assist in development of pharmacological treatments for Alzheimer's disease. ..

..The relevance of this project is in developing new, effective interventions for restoring visual acuity and stereopsis in adults and children with amblyopia. ..

..Thus, the proposed research will provide essential information for understanding conditions that involve deficits in the control of gaze. ..

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..In addition, the proposed methods, conceptual framework, and findings can provide the basis for assessing flexibility in children with motor impairments and for tracking improvements in flexibility with therapy. ..

..It also has great relevance to retinal or neurological diseases which may affect the M or P cells selectively. Thus, this project has relevance to medical diagnosis and treatment of visual diseases in humans...

..This project contributes directly to public health by developing a low cost image enhancement system for use by this growing population of visually impaired people. ..

..The proposed program of research develops new diagnostics that are sensitive to the early stages of neuro-degeneration in glaucoma. ..

..Patterns of facilitation and inhibition are used to decide what aspects of motion information receive implicit registration. ..

The goal of this proposal is to investigate the mechanism by which learning and adaptation can alter the orientation tuning of neurons in primary visual cortex...

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..Only by developing a better understanding of the nature of observer error, may we discover effective approaches to reducing the errors. ..

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..It could lead to a better understanding of the neural mechanisms underlying cognitive functions, as well as to potential applications for revealing mechanisms of neural disorders. ..

..I plan to conduct these studies employing sophisticated neuroimaging and analytical techniques to examine the dynamic interactions of the DLPFC with the visual system. ..

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..Increased understanding of the fundamental mechanisms of biological clock function will facilitate the development of better treatment strategies for a wide range of disorders. ..

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