Dissertations / Theses: 'Spatial perception'

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Richez, Aurélien. "Perception spatiale et compétences motrice : approche développement et neuropsychologique." Thesis, Lille 3, 2014. http://www.theses.fr/2014LIL30054/document.

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Les théories qui modélisent la perception spatiale chez l'adulte s'accordent à postuler l'existence de liens forts entre la perception et l'action(James, 1892 ; Poincaré, 1902 ; Gibson, 1979 ; Noe, 2004). Une vaste collection de données montre également que ces liens sont présents dans le développement ontogénétique. Ce travail de thèse vise à examiner les implications de tels liens dans le développement de la perception spatiale et d'en identifier les déterminants chez l'enfant. Nous avons mené une série d'expériences, basée sur l'utilisation des paradigmes d'atteignabilité et d'amorçage visuomoteur, autour de la problématique de l'élaboration et l'utilisation des représentations perceptives et sensorimotrices dans la perception spatiale. Nous avons mené ces expériences chez une population d'adultes et d'enfants âgées de 7 à 13 ans avec l'objectif d'évaluer la trajectoire développementale de la perception spatiale. Les résultats obtenus mettent en évidence des discontinuités dans les trajectoires développementales des différentes tâches proposées. Nous avons mis en évidence les marqueurs de ces changements développementaux dans les performances des tâches d'atteignabilité, d'imagerie motrice et également d'amorçage visuomoteur. Nous interprétons ces résultats comme relevant d'un changement qualitatif de la perception spatiale durant cette période. D'une manière générale, les travaux présentés dans cette thèse apportent des données nouvelles sur le développement de la perception spatiale chez l'enfant, et sont mis en relation avec la littérature en psychologie et en neurosciences du développement
Spatial perception and motor skills : a developmental approach

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2

Philip, Jean. "La pseudonégligence peut-elle rendre compte des asymétries de la perception de l'espace latéral en modalité tactilo-kinésthésique ?" Grenoble 2, 1995. http://www.theses.fr/1995GRE29020.

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La pseudonegligence observee chez les normaux (bowers et heilman, 1980) consiste a repondre a gauche du centre objectif quand on demande de partager des lignes horizontales par le milieu. Certains l'expliquent par la nature spatiale de la tache qui, en activant l'hemisphere d, entrainerait un "surdimensionnement" de la partie g du stimulus. Mais son instabilite souligne aussi la puissance du biais d'orientation vers la d. D'autres pensent que le sens de l'exploration determine celui des deviations, ou invoquent un amorcage de l'attention du cote ou debute l'exploration. Nous avons teste l'hypothese de l'existence dans cette tache de composantes sensorielle et motrice s'exercant en sens inverse. Nos resultats ne confirment pas la pseudonegligence et ne montrent pas de difference entre les sujets aveugles et voyants. Chaque main devie dans l'hemiespace controlateral. D'autre part, si on impose toujours le meme sens d'exploration, les deviations suivent ce sens. Mais, lorsqu'on amorce lateralement l'attention avant l'exploration, les erreurs sont attirees du cote de l'amorcage. La discussion porte sur la theorie d'activation hemispherique et sur l'hypothese d'un decalage du referentiel egocentre
Bowers and heilman (1980) observed that when righthanded adults were asked to locate, in the hapic modality, the midpoint of a horizontal line, both hands tended to deviate to the left of the true midpoint. This error, called "pseudoneglect" by reference to the rightward error of patients suffering from right posterior brain lesions, was also observed in vision and has been explained by hemispheric activation theories. Because bisection is spatial in nature, it would activate the right hemisphere and would therefore induce a left lateral shift of attention. In our research on bisection in the haptic modality of normal blindfolded and totally blind adults, we first replicated bowers and heilman's results (sampaio & philip, 1991). But further studies failed to confirm the existence of pseudoneglect. Actually, each hand tended to deviate in the contralateral space. In addition, when the direction of exploration of the line to be bisected was constrained (from left-to-right only, or from right-to-left), the responses were deviated in the direction of the arm movement. Finally, attentional priming of one end of the stimulus tended to deviate the subjective midpoint in the direction of the lateral cue. These results are discussed in relation to hemispheric activation theories and to the hypothesis assuming changes in the egocentric reference frame

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Hendicott, Peter Leslie. "Spatial perception and progressive addition lenses." Thesis, Queensland University of Technology, 2007. https://eprints.qut.edu.au/16468/1/Peter_Hendicott_Thesis.pdf.

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Progressive addition lenses (PALs) are an increasingly preferred mode for the correction of presbyopia, gaining an increased share of the prescription lens market. Sales volumes are likely to increase over the next few years, given the increasing cohort of presbyopic patients in the population. This research investigated adaptation to PAL wear, investigating head movement parameters with and without progressive lenses in everyday visual tasks, and examined symptoms of spatial distortions and illusory movement in a crossover wearing trial of three PAL designs. Minimum displacement thresholds in the presence and absence of head movement were also investigated across the lens designs. Experiment 1 investigated head movements in two common visual tasks, a wordprocessing copy task, and a visual search task designed to replicate a natural environment task such as looking for products on supermarket shelving. Head movement parameters derived from this experiment were used to set head movement amplitude and velocity in the third experiment investigating minimum displacement thresholds across three PAL designs. Head movements were recorded with a Polhemus Inside Track head movement monitoring system which allows real time six degrees of freedom measurement of head position. Head position in azimuth, elevation and roll was extracted from the head movement recorder output, and data for head movement angular extent, average velocity (amplitude/duration) and peak velocity were calculated for horizontal head movements Results of the first experiment indicate a task dependent effect on head movement peak and average velocity, with both median head movement average and peak velocity being faster in the copy task. Visual task and visual processing demands were also shown to affect the slope of the main sequence of head movement velocity on head movement amplitude, with steeper slope in the copy task. A steeper slope, indicating a faster head movement velocity for a given head movement amplitude, was found for head movements during the copy task than in the search task. Processing demands within the copy task were also shown to affect the main sequence slopes of velocity on amplitude, with flatter slopes associated with the need for head movement to bring gaze to a specific point. These findings indicate selective control over head movement velocity in response to differing visual processing demands. In Experiment 2, parameters of head movement amplitude and velocity were assessed in a group of first time PAL wearers. Head movement amplitude, average and peak velocity were calculated from head movement recordings using the search task, as in Experiment 1. Head movements were recorded without PALs, on first wearing a PAL, and after one month of PAL wear to assess adaptation effects. In contrast to existing literature, PAL wear did not alter parameters of head movement amplitude and velocity in a group of first time wearers either on first wearing the lenses or after one month of wear: this is due to task related effects in this experiment compared to previous work. Task demand in this experiment may not have required wearers to use the progressive power corridor to accomplish identification of visual search targets, in contrast to previous studies where experimental conditions were designed to force subjects to use the progressive corridor. In Experiment 3, minimum displacement thresholds for random dot stimuli were measured in a repeated measures experimental design for a single vision lens as control, and three PAL designs. Thresholds were measured in central vision, and for two locations in the temporal peripheral field, 30° temporal fixation and 10° above and below the horizontal midline. Thresholds were determined with and without the subjects' head moving horizontally in an approximate sinusoidal movement at a frequency of about 0.7 Hz. Minimum displacement thresholds were not significantly affected by PAL design, although thresholds with PALs were higher than with a single vision lens control. Head movement significantly increased minimum displacement threshold across lens designs, by a factor of approximately 1.5 times. Results indicate that the local measures of minimum displacement threshold determined in this experiment are not sensitive to lens design differences. Sensitivity to motion with PAL lenses may be more a global than a localized response. For Experiment 4, symptoms of spatial distortion and illusory movement were investigated in a crossover wearing trial of three PAL designs, and related to optical characteristics of the lenses. Peripheral back vertex powers of the PALs were measured at two locations in the right temporal zone of the lenses, 15.6 mm temporal to the fitting cross, and 2.7 m above and below the horizontal to the fitting cross. These locations corresponded to the zones of the lenses through which minimum displacement thresholds were measured in the previous experiment. The effect of subjects' self movement on symptoms is able to discriminate between PAL designs, although subjective symptoms alone were not related to the lens design parameters studied. Subjects' preference for one PAL design over the other designs studied in this experiment is inversely related to the effect on subject movement on their symptoms of distortion. An optical parameter, blur strength, derived from the power vector components of the peripheral powers, may indicate preference for particular PAL designs, as higher blur strength values are associated with lower lens preference scores. Head movement amplitude and velocity are task specific, and are also influenced by visual processing demands within tasks. PALs do not affect head movement amplitude and velocity unless tasks are made demanding or performed in less natural situations designed to influence head movement behaviour. Both head movement and PALs have large effects on minimum displacement thresholds; these effects may be due in part to complexity of the subjects' task within the experiment. Minimum displacement thresholds however were not influenced by PAL design. The most sensitive indicator for subject's preference of PALs was the effect of subjects' self movement on their perception of symptoms, rather than the presence of actual symptoms. Blur strength should be further investigated for its role in PAL acceptance.

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Hendicott, Peter Leslie. "Spatial perception and progressive addition lenses." Queensland University of Technology, 2007. http://eprints.qut.edu.au/16468/.

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Progressive addition lenses (PALs) are an increasingly preferred mode for the correction of presbyopia, gaining an increased share of the prescription lens market. Sales volumes are likely to increase over the next few years, given the increasing cohort of presbyopic patients in the population. This research investigated adaptation to PAL wear, investigating head movement parameters with and without progressive lenses in everyday visual tasks, and examined symptoms of spatial distortions and illusory movement in a crossover wearing trial of three PAL designs. Minimum displacement thresholds in the presence and absence of head movement were also investigated across the lens designs. Experiment 1 investigated head movements in two common visual tasks, a wordprocessing copy task, and a visual search task designed to replicate a natural environment task such as looking for products on supermarket shelving. Head movement parameters derived from this experiment were used to set head movement amplitude and velocity in the third experiment investigating minimum displacement thresholds across three PAL designs. Head movements were recorded with a Polhemus Inside Track head movement monitoring system which allows real time six degrees of freedom measurement of head position. Head position in azimuth, elevation and roll was extracted from the head movement recorder output, and data for head movement angular extent, average velocity (amplitude/duration) and peak velocity were calculated for horizontal head movements Results of the first experiment indicate a task dependent effect on head movement peak and average velocity, with both median head movement average and peak velocity being faster in the copy task. Visual task and visual processing demands were also shown to affect the slope of the main sequence of head movement velocity on head movement amplitude, with steeper slope in the copy task. A steeper slope, indicating a faster head movement velocity for a given head movement amplitude, was found for head movements during the copy task than in the search task. Processing demands within the copy task were also shown to affect the main sequence slopes of velocity on amplitude, with flatter slopes associated with the need for head movement to bring gaze to a specific point. These findings indicate selective control over head movement velocity in response to differing visual processing demands. In Experiment 2, parameters of head movement amplitude and velocity were assessed in a group of first time PAL wearers. Head movement amplitude, average and peak velocity were calculated from head movement recordings using the search task, as in Experiment 1. Head movements were recorded without PALs, on first wearing a PAL, and after one month of PAL wear to assess adaptation effects. In contrast to existing literature, PAL wear did not alter parameters of head movement amplitude and velocity in a group of first time wearers either on first wearing the lenses or after one month of wear: this is due to task related effects in this experiment compared to previous work. Task demand in this experiment may not have required wearers to use the progressive power corridor to accomplish identification of visual search targets, in contrast to previous studies where experimental conditions were designed to force subjects to use the progressive corridor. In Experiment 3, minimum displacement thresholds for random dot stimuli were measured in a repeated measures experimental design for a single vision lens as control, and three PAL designs. Thresholds were measured in central vision, and for two locations in the temporal peripheral field, 30° temporal fixation and 10° above and below the horizontal midline. Thresholds were determined with and without the subjects' head moving horizontally in an approximate sinusoidal movement at a frequency of about 0.7 Hz. Minimum displacement thresholds were not significantly affected by PAL design, although thresholds with PALs were higher than with a single vision lens control. Head movement significantly increased minimum displacement threshold across lens designs, by a factor of approximately 1.5 times. Results indicate that the local measures of minimum displacement threshold determined in this experiment are not sensitive to lens design differences. Sensitivity to motion with PAL lenses may be more a global than a localized response. For Experiment 4, symptoms of spatial distortion and illusory movement were investigated in a crossover wearing trial of three PAL designs, and related to optical characteristics of the lenses. Peripheral back vertex powers of the PALs were measured at two locations in the right temporal zone of the lenses, 15.6 mm temporal to the fitting cross, and 2.7 m above and below the horizontal to the fitting cross. These locations corresponded to the zones of the lenses through which minimum displacement thresholds were measured in the previous experiment. The effect of subjects' self movement on symptoms is able to discriminate between PAL designs, although subjective symptoms alone were not related to the lens design parameters studied. Subjects' preference for one PAL design over the other designs studied in this experiment is inversely related to the effect on subject movement on their symptoms of distortion. An optical parameter, blur strength, derived from the power vector components of the peripheral powers, may indicate preference for particular PAL designs, as higher blur strength values are associated with lower lens preference scores. Head movement amplitude and velocity are task specific, and are also influenced by visual processing demands within tasks. PALs do not affect head movement amplitude and velocity unless tasks are made demanding or performed in less natural situations designed to influence head movement behaviour. Both head movement and PALs have large effects on minimum displacement thresholds; these effects may be due in part to complexity of the subjects' task within the experiment. Minimum displacement thresholds however were not influenced by PAL design. The most sensitive indicator for subject's preference of PALs was the effect of subjects' self movement on their perception of symptoms, rather than the presence of actual symptoms. Blur strength should be further investigated for its role in PAL acceptance.

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5

Tamè, Luigi. "Multiple Spatial Representations for Haptic Perception." Doctoral thesis, Università degli studi di Trento, 2010. https://hdl.handle.net/11572/368662.

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In everyday life, our body gets in contact with multiple tactile stimuli from the outside world. How our somatosensory system identifies and localises these multiple stimuli entering in contact with our body surface, is the general framework to which the researches of the present thesis belong. Tactile stimuli on our body can be spatially coded and represented by using multiple reference frames. Touch is initially encoded into a sensory-space within primary somatosensory map and then further stages of processing can represent the location of tactile event with respect to the overall body structure (body-space) or to the outside world (external-space). In the present thesis we report first a series of behavioural experiments aimed at investigating which spatial reference frame is adopted in a special context of sensory stimulation, namely the double simultaneous stimulation (DSS). Then, we used functional magnetic resonance (fMRI) as a tool for delineating the neural bases of the cognitive processes sub-serving the elaboration and representation of concurrent stimuli for conscious tactile perception. In a first behavioural study using the tactile DSS paradigm, we defined the spatial coding used by observers when tactile stimuli are delivered with different fingers combinations (i.e., within vs. between hands) and hand postures (i.e., hands palm-down vs. palm-up). In a second behavioural work we tested the influence of different visual modulations (e.g., seeing body parts or objects) and visual-proprioceptive conflict (e.g., seeing body parts in a different position with respect to one adopted by the participant) on the spatial representation of touch. Furthermore, we investigated the effect of changes to the visual structural morphology of a body part on the spatial representation of touch. Finally, using a fMRI adaptation paradigm for touches at the fingers, we aimed to define the neural bases of tactile perception in a repeated stimulations context. In particular, we assessed the mutual interaction between tactile stimuli located at body parts that are clearly distinct in terms of the body-space (e.g., left and right index fingers), but proximal in terms of neural representations (due to some bilateral responses of the somatosensory cortices).

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Tamè, Luigi. "Multiple Spatial Representations for Haptic Perception." Doctoral thesis, University of Trento, 2010. http://eprints-phd.biblio.unitn.it/168/1/Luigi_Tam%C3%A8_PhD_Thesis.pdf.

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In everyday life, our body gets in contact with multiple tactile stimuli from the outside world. How our somatosensory system identifies and localises these multiple stimuli entering in contact with our body surface, is the general framework to which the researches of the present thesis belong. Tactile stimuli on our body can be spatially coded and represented by using multiple reference frames. Touch is initially encoded into a sensory-space within primary somatosensory map and then further stages of processing can represent the location of tactile event with respect to the overall body structure (body-space) or to the outside world (external-space). In the present thesis we report first a series of behavioural experiments aimed at investigating which spatial reference frame is adopted in a special context of sensory stimulation, namely the double simultaneous stimulation (DSS). Then, we used functional magnetic resonance (fMRI) as a tool for delineating the neural bases of the cognitive processes sub-serving the elaboration and representation of concurrent stimuli for conscious tactile perception. In a first behavioural study using the tactile DSS paradigm, we defined the spatial coding used by observers when tactile stimuli are delivered with different fingers combinations (i.e., within vs. between hands) and hand postures (i.e., hands palm-down vs. palm-up). In a second behavioural work we tested the influence of different visual modulations (e.g., seeing body parts or objects) and visual-proprioceptive conflict (e.g., seeing body parts in a different position with respect to one adopted by the participant) on the spatial representation of touch. Furthermore, we investigated the effect of changes to the visual structural morphology of a body part on the spatial representation of touch. Finally, using a fMRI adaptation paradigm for touches at the fingers, we aimed to define the neural bases of tactile perception in a repeated stimulations context. In particular, we assessed the mutual interaction between tactile stimuli located at body parts that are clearly distinct in terms of the body-space (e.g., left and right index fingers), but proximal in terms of neural representations (due to some bilateral responses of the somatosensory cortices).

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AGGIUS-VELLA, ELENA. "From sensory perception to spatial cognition." Doctoral thesis, Università degli studi di Genova, 2019. http://hdl.handle.net/11567/940911.

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To interact with the environmet, it is crucial to have a clear space representation. Several findings have shown that the space around our body is split in several portions, which are differentially coded by the brain. Evidences of such subdivision have been reported by studies on people affected by neglect, on space near (peripersonal) and far (extrapersonal) to the body position and considering space around specific different portion of the body. Moreover, recent studies showed that sensory modalities are at the base of important cognitive skills. However, it is still unclear if each sensory modality has a different role in the development of cognitive skills in the several portions of space around the body. Recent works showed that the visual modality is crucial for the development of spatial representation. This idea is supported by studies on blind individuals showing that visual information is fundamental for the development of auditory spatial representation. For example, blind individuals are not able to perform the spatial bisection task, a task that requires to build an auditory spatial metric, a skill that sighted children acquire around 6 years of age. Based these prior researches, we hypothesize that if different sensory modalities have a role on the devlopment of different cognitive skills, then we should be able to find a clear correlation between availability of the sensory modality and the cognitive skill associated. In particular we hypothesize that the visual information is crucial for the development of auditory space represnetation; if this is true, we should find different spatial skill between front and back spaces. In this thesis, I provide evidences that spaces around our body are differently influenced by sensory modalities. Our results suggest that visual input have a pivotal role in the development of auditory spatial representation and that this applies only to the frontal space. Indeed sighted people are less accurated in spatial task only in space where vision is not present (i.e. the back), while blind people show no differences between front and back spaces. On the other hand, people tend to report sounds in the back space, suggesting that the role of hearing in allertness could be more important in the back than frontal spaces. Finally, we show that natural training, stressing the integration of audio motor stimuli, can restore spatial cognition, opening new possibility for rehabilitation programs. Spatial cognition is a well studied topic. However, we think our findings fill the gap regarding how the different availibility of sensory information, across spaces, causes the development of different cognitive skills in these spaces. This work is the starting point to understand the strategies that the brain adopts to maximize its resources by processing, in the more efficient way, as much information as possible.

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Martin, Romain. "Encodage spatial et intelligence." Nancy 2, 1998. http://www.theses.fr/1998NAN21014.

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La thèse est organisée en deux parties. Une première partie présente la littérature consacrée à l'étude de la cognition spatiale. Cette présentation s'inscrit dans une approche interdisciplinaire (psychologie, neurophysiologie, sciences de l'information, éthologie, philosophie). Il est notamment analysé comment les différences interindividuelles en cognition spatiale sont décrites par ces différentes disciplines. Une attention particulière sera donnée à des différences qualitatives de traitement, c'est-à-dire aux stratégies mises en oeuvre pour réaliser des traitements visuo-spatiaux. On analysera également les différences dans la qualité des représentations construites à partir d'une exploration d'un espace tridimensionnel. Il sera essayé de dresser un cadre interprétatif intégratif des différences constatées sur la base de la théorie neurologiquement plausible de Kosslyn introduisant la distinction entre un subsystème catégoriel et métrique pour l'encodage des relations spatiales. L'hypothèse est émise que l'efficacité de fonctionnement de ces subsystèmes peut constituer un élément explicatif important pour les différences interindividuelles en cognition spatiale. Dans la deuxième partie, on présentera 4 expériences impliquant la mesure de la qualité de l'encodage spatial à l'aide de dispositifs sur support informatique. Un de ces dispositifs est plus spécialement destiné à évaluer la précision de l'encodage spatial et montre la stabilité des différences interindividuelles constatées, ainsi que la relation entre précision d'encodage et performance à des épreuves de type papier-crayon. Il s'avère que cette dernière relation est importante, surtout en ce qui concerne les facteurs spatial et général. Une épreuve d'exploration d'un espace virtuel en 3D permet en plus d'évaluer l'impact de la précision de l'encodage spatial sur l'efficacité de déplacement. Les résultats sont interprétés dans le cadre neurologiquement plausible de la théorie de Kosslyn
The dissertation is organized in two parts. The first part presents the literature concerning the study of spatial cognition. This representation adopts an interdisciplinary approach (psychology, neurophysiology, information sciences, ethology, philosophy). Of special interest are interindividual differences in spatial cognition as described by these disciplines. Particular attention is payed to qualitative processing differences, i. E. Different strategies for processing of visuo-spatial information. Individual differences in the quality of representations constructed from navigation in a threedimensional space are also analysed. The attempt is made to create an integrative framework of interpretation for the described differences on the basis of the neurologically plausible theory of Kosslyn introducing the distinction between categorical and metric spatial relations encoding. The hypothesis is made that the efficiency of these subsystems may represent an important element in the explanation of interindividual differences in spatial cognition. In the second part, 4 experiences are presented which imply the measurement of the quality of spatial relations encoding with computer-assisted tests. One of these tests measures specifically the precision of spatial relations encoding and shows stability of individual differences, as well as the relation between spatial relations encoding precision and performance on paper and pencil tests. This relation seems important, especially with the spatial and general factors of intelligence. A navigation test in a virtual environment furthermore permits to evaluate the influence of spatial relations encoding precision on wayfinding performance. Results are interpreted in the framework of Kosslyn's neurologically plausible theory of visuo-spatial information processing

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Knauff, Markus. "Räumliches Wissen und Gedächtnis : zur Wissenspsychologie des kognitiven Raums /." Wiesbaden : Deutscher Universitäts-Verlag, 1997. http://catalogue.bnf.fr/ark:/12148/cb37083409x.

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Bailleux, Christine. "Identification de formes ambigue͏̈s : approche différentielle des référentiels spatiaux d'orientation." Grenoble 2, 1995. http://www.theses.fr/1995GRE29022.

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Ce travail a pour objet de proposer un nouvel eclairage a la theorie des cadres de reference d'orientation associee aux taches d'identification de formes. Deux courants de recherches, appartenant a la psychologie cognitive generale et a la psychologie differentielle, se sont interesse aux referentiels spatiaux d'orientation, mais il ont rarement ete mis en relation. Ce travail se propose de rapprocher la theorie des cadres de reference, elaboree par les cognitivistes, et l'etude de la dependanceindependance a l'egard du champ (dic) au travers de la vicariance des processus perceptifs. Une revue de la litterature montre l'importance d'une prise en compte conjointe des traitements d'identification et d'orientation et met, egalement, en evidence la necessite de considerer les differences individuelles dans le recours aux references visuelles d'orientation. L'hypothese generale, testee ici, est que le style cognitif des individus aura des repercussions sur la resolution d'une tache d'identification de formes ambigues. Autrement dit, que les resultats classiquement observes d'une relative dependance des sujets aux informations visuelles contextuelles dans les taches d'identification de formes est fonction du degre de dependance des individus a l'egard du referentiel visuel d'orientation. Les travaux empiriques portent sur le role du contexte visuel et l'influence des variations posturales sur la resolution de la tache de kopermann. De facon generale, les resultats vont dans le sens attendu: les sujets reperes sur la base du rft comme dependants a l'egard du referentiel visuel sont ceux qui ont le plus de difficulte a resoudre la tache d'identification. Cependant, cette dependance a l'egard du referentiel visuel peut etre modulee en fonction de la nature du contexte visuel presente et des variations posturales introduites lors de la passation de l'epreuve. L'ensemble de ces resultats amenent a formuler des hypotheses en termes de demandes attentionnelles mais celles-ci sont encore a verifier
The aim of this work is to propose a new point of view of the reference frame theory. Cognitive psychologists and differential psychologists were interested in spatial reference frames but their points of view were rarely associated. This work tried to bring together reference frame theory and cognitive style of field-dependence-independence (fdi). The emphasis was placed on the necessity to take into account orientation and identification processing and individual differences in identification of ambiguous shapes. The general hypothesis was that the cognitive style influence the resolution of identification task when ambiguity was due ambiguous orientation. Field dependent subjects were dependent to visual reference both in identification and orientation tasks. The empirical results were analysed in two directions: the influence of visual context and the effect of modulation of postural balance. Results were congruent with theoretical hypotheses but a last research , concerned pop-out treisman's paradigm, led to re-analyse all the results in terms of visual-spatial attention theory and differential attentional demands

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Griffiths, Shaaron S., and shaaron griffiths@deakin edu au. "Spatial and temporal disparaties in aurally aided visual search." Deakin University. School of Psychology, 2001. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20061207.134032.

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Research over the last decade has shown that auditorily cuing the location of visual targets reduces the time taken to locate and identify targets for both free-field and virtually presented sounds. The first study conducted for this thesis confirmed these findings over an extensive region of free-field space. However, the number of sound locations that are measured and stored in the data library of most 3-D audio spatial systems is limited, so that there is often a discrepancy in position between the cued and physical location of the target. Sampling limitations in the systems also produce temporal delays in which the stored data can be conveyed to operators. To investigate the effects of spatial and temporal disparities in audio cuing of visual search, and to provide evidence to alleviate concerns that psychological research lags behind the capabilities to design and implement synthetic interfaces, experiments were conducted to examine (a) the magnitude of spatial separation, and (b) the duration of temporal delay that intervened between auditory spatial cues and visual targets to alter response times to locate targets and discriminate their shape, relative to when the stimuli were spatially aligned, and temporally synchronised, respectively. Participants listened to free-field sound localisation cues that were presented with a single, highly visible target that could appear anywhere across 360° of azimuthal space on the vertical mid-line (spatial separation), or extended to 45° above and below the vertical mid-line (temporal delay). A vertical or horizontal spatial separation of 40° between the stimuli significantly increased response times, while separations of 30° or less did not reach significance. Response times were slowed at most target locations when auditory cues occurred 770 msecs prior to the appearance of targets, but not with similar durations of temporal delay (i.e., 440 msecs or less). When sounds followed the appearance of targets, the stimulus onset asynchrony that affected response times was dependent on target location, and ranged from 440 msecs at higher elevations and rearward of participants, to 1,100 msecs on the vertical mid-line. If targets appeared in the frontal field of view, no delay of acoustical stimulation affected performance. Finally, when conditions of spatial separation and temporal delay were combined, visual search times were degraded with a shorter stimulus onset asynchrony than when only the temporal relationship between the stimuli was varied, but responses to spatial separation were unaffected. The implications of the results for the development of synthetic audio spatial systems to aid visual search tasks was discussed.

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Higginbotham, Alexia J. "Aging and Visual Spatial Integration." TopSCHOLAR®, 2019. https://digitalcommons.wku.edu/theses/3099.

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The current study evaluated the ability of 20 younger and 20 older adults to discriminate shapes depicted by Glass patterns. On any given trial, observers identified a particular pattern as either possessing a radial or concentric organization. Detecting a shape defined by a Glass pattern requires the successful detection of the orientations of its constituent local dipoles. In addition, long-range processes are needed to integrate the spatially separated dipoles into perceivable contours that have a particular (e.g., radial or concentric) organization. In the current experiment, the shapes were defined by either 40 or 200 oriented dipoles spread over an area with a diameter of either 6 or 25 degrees visual angle. Three amounts of visual noise were added to the patterns to manipulate task difficulty: 1) no added noise points, 2) low amounts of noise (a 1:1 ratio of randomlyplaced noise points and signal dipoles), and 3) large amounts of noise (a 5:1 ratio of randomly-placed noise points and signal dipoles). The results of the current study indicate that human observers, both younger and older, possess an effective ability to integrate visual information across space (using Glass patterns as stimuli). There is a small age-related deterioration in discrimination performance and this is most likely due to the deficits in orientation discrimination that accompany reductions in inhibitory GABA activity in visual cortex.

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MacBride, S. J. C. "Socio-spatial isomorphism." Thesis, University of St Andrews, 1999. http://hdl.handle.net/10023/2894.

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It is contended that space can act as a metaphor for social relationships. The thesis draws on schema theory from cognitive psychology to explain how the affective qualities of social stimuli serve to bias the 'cognitive maps' of individuals. Supporting evidence is cited from the fields of cognitive, social, environmental and neuro-psychology. The metaphor is tested experimentally from a micro-spatial level (e. g. spatial locations of characters in a photograph) up to a macro-spatial level (spatial locations of towns). The affective valence of the stimuli used were either a priori based (e. g. homes of people already known to the subject, perceived religious predominance of towns in a sectarian setting) or influenced by the experimenter (e. g. captions purporting to inform representations of social scenes in photographs derived from newspapers and magazines). Distortion of perceived distances (between subject and stimuli and between stimuli) form the dependent variable in each experiment. Results in all experiments indicated a strong tendency for the valence of stimuli to bias people in their distance estimations. Relative overestimation of distance was observed for stimuli perceived to be negatively valenced and the reverse for those stimuli perceived to be positively valenced. In a final experiment, distance estimations were examined between a variety of human figures photographed in 'real-world' social encounters. The results were in line with Social Identity Theory, with overestimation observed between groups and underestimation within groups. Results throughout are interpreted in relation to the 'socio-spatial schema' metaphor.

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Eagle, Richard A. "Spatial characteristics of human visual motion perception." Thesis, University of Oxford, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.334872.

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Keating, Peter. "Plasticity and integration of auditory spatial cues." Thesis, University of Oxford, 2011. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.561113.

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Although there is extensive evidence that auditory spatial processing can adapt to changes in auditory spatial cues both in infancy and adulthood, the mechanisms underlying adaptation appear to differ across species. Whereas barn owls compensate for unilateral hearing loss throughout development by learning abnormal mappings between cue values and spatial position, adult mammals seem to adapt by ignoring the acoustical input available to the affected ear and learning to rely more on unaltered spatial cues. To investigate these differences further, ferrets were raised with a unilateral earplug and their ability to localize sounds was assessed. Although these animals did not fully compensate for the effects of an earplug, they performed considerably better than animals that experienced an earplug for the first time, indicating that adaptation had taken place. We subsequently found that juvenile-plugged (JP) ferrets learned to adjust both cue mappings and weights in response to changes in acoustical input, with the nature of these changes reflecting the expected reliability of different cues. Thus, the auditory system may be able to rapidly update the way in which individual cues are processed, as well as the way in which different cues are integrated, thereby enabling spatial cues to be processed in a context- specific way. In attempting to understand the mechanisms that guide plasticity of spatial hearing, previous studies have raised the possibility that changes in auditory spatial processing may be driven by mechanisms intrinsic to the auditory system. To address this possibility directly, we measured the sensitivity of human subjects to ITDs and ILDs following transient misalignment of these cues. We found that this induces a short-term recalibration that acts to compensate for the effects of cue misalignment. These changes occurred in the absence of error feedback, suggesting that mutual recalibration can occur between auditory spatial cues. The nature of these changes, however, was consistent with models of cue integration, suggesting that plasticity and integration may be inextricably linked. Throughout the course of this work, it became clear that future investigations would benefit from the application of closed-field techniques to the ferret. For this reason, we developed and validated methods that enable stimuli to be presented to ferrets over earphones, and used these methods to assess ITD and ILD sensitivity in ferrets using a variety of different stimuli. We found that the Duplex theory is able to account for binaural spatial sensitivity in these animals, and that sensitivity is comparable with that found in humans, thereby confirming the ferret as an excellent model for understanding binaural spatial hearing.

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Collin, Charles Alain. "Effects of spatial frequency overlap on face and object recognition." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36896.

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There has recently been much interest in how limitations in spatial frequency range affect face and object perception. This work has mainly focussed on determining which bands of frequencies are most useful for visual recognition. However, a fundamental question not yet addressed is how spatial frequency overlap (i.e., the range of spatial frequencies shared by two images) affects complex image recognition. Aside from the basic theoretical interest this question holds, it also bears on research about effects of display format (e.g., line-drawings, Mooney faces, etc.) and studies examining the nature of mnemonic representations of faces and objects. Examining the effects of spatial frequency overlap on face and object recognition is the main goal of this thesis.
A second question that is examined concerns the effect of calibration of stimuli on recognition of spatially filtered images. Past studies using non-calibrated presentation methods have inadvertently introduced aberrant frequency content to their stimuli. The effect this has on recognition performance has not been examined, leading to doubts about the comparability of older and newer studies. Examining the impact of calibration on recognition is an ancillary goal of this dissertation.
Seven experiments examining the above questions are reported here. Results suggest that spatial frequency overlap had a strong effect on face recognition and a lesser effect on object recognition. Indeed, contrary to much previous research it was found that the band of frequencies occupied by a face image had little effect on recognition, but that small variations in overlap had significant effects. This suggests that the overlap factor is important in understanding various phenomena in visual recognition. Overlap effects likely contribute to the apparent superiority of certain spatial bands for different recognition tasks, and to the inferiority of line drawings in face recognition. Results concerning the mnemonic representation of faces and objects suggest that these are both encoded in a format that retains spatial frequency information, and do not support certain proposed fundamental differences in how these two stimulus classes are stored. Data on calibration generally shows non-calibration having little impact on visual recognition, suggesting moderate confidence in results of older studies.

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Fulmer, Hilary Renee. "Visual influences on limitations of space spatial depth perception versus spatial definition /." Cincinnati, Ohio : University of Cincinnati, 2006. http://www.ohiolink.edu/etd/view.cgi?acc%5Fnum=ucin1147885019.

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Thesis (Master of Architecture)--University of Cincinnati, 2006.
Title from electronic thesis title page (viewed July 24, 2006). Includes abstract. Keywords: spatial limitations; spatial perception; spatial depth; spatial definition; reflection; representation; transparency; visual fluctuation; spatial fluctuation; movement. Includes bibliographical references.

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FULMER, HILARY RENEE. "VISUAL INFLUENCES ON LIMITATIONS OF SPACE: SPATIAL DEPTH PERCEPTION VERSUS SPATIAL DEFINITION." University of Cincinnati / OhioLINK, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1147885019.

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Luyat, Marion. "La perception visuelle de la verticale : rôle de l'activité posturale et de l'orientation du corps." Grenoble 2, 1996. http://www.theses.fr/1996GRE29010.

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Ces recherches s'inscrivent dans le domaine de l'orientation spatiale et concernent en particulier le role de la posture dans la perception de la verticale (verticale subjective visuelle). Dans le cadre de l'approche ecologique de l'orientation spatiale (stoffregen & riccio, 1988), l'effet du controle actif de la posture sur la perception de la verticale est etudie, dans une premiere serie d'experiences, en manipulant le degre de sollicitation posturale de l'individu. Les resultats montrent que la gestion de l'equilibre n'est pas une condition indispensable pour effectuer un jugement perceptif visuel de verticalite. La position de l'axe z semble en revanche jouer un role important. De fait, d'une etude specifiquement centree sur le versant actif de la posture, ces donnees conduisent la recherche vers une prise en compte du versant statique de la posture. Afin d'etudier la contribution de l'axe z, une deuxieme serie d'experiences est realisee. La perception de la verticale est evaluee en decubitus dorsal lors de modifications de la position du corps au sol et egalement en presence de references visuelles susceptibles d'induire une inclinaison du plan median apparent. Les resultats mettent en evidence un role important de la position du corps, en particulier de la position du corps par rapport a la cible. Des deviations systematiques de la verticale sont par ailleurs observees lorsque le contexte visuel induit un deplacement subjectif du plan median. Concernant le jugement visuel de verticalite, l'ensemble des donnees suggere une implication importante de la position du corps, reelle (deviation du regard) ou fictive (deviation du plan median apparent), par rapport a la cible
These studies are in line with the domain of spatial orientation and concern more particularly the visual perception of the vertical (visual subjective vertical). Referring to stoffregen & riccio's theory, the role of postural activity has been tested in a first series of experiments. Results showed that postural activity was not a crucial factor to accurately perceive the vertical orientation. By contrast, the main position of the body axis (z-axis) seemed to be an important factor. To study the role of this z-axis, a second series of experiments was conducted. The perception of the vertical was estimated with real modifications of z-axis orientation in supine posture and in the dark or in the presence of a tilted frame. Results revealed important shifts of the subjective vertical both in the condition of real modification of z-axis position and in the condition of virtual modification of z-axis. Finally, the corpus of data suggested an important contribution of the position (real or virtual) of the body in space

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Colliot, Pascale. "Perception de l'espace chez les sujets sains et cérébro-lésés : implication pour l'étude de la Négligence Spatiale Unilatérale." Grenoble 2, 2002. http://www.theses.fr/2002GRE29034.

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Longtemps définie comme un trouble attentionnel et/ou représentationnel, la Négligence Spatiale Unilatérale (NSU) est depuis une dizaine d'années décrite comme une perturbation du référentiel égocentrique (RE) prenant la forme d'une déviation ipsilésionnelle. Cette hypothèse "référentielle" propose ainsi un lien de cause à effet entre une distorsion du RE et le comportement de négligence. Grâce à l'étude conjointe des sujets sains et des patients cérébro-lésés, l'objectif de cette étude consiste essentiellement à tester cette hypothèse. Aucune des expériences réalisées ne permet de concevoir la NSU comme la conséquence d'une déviation ipsilésionnelle du RE, et nos résultats remettent en cause le rôle prépondérant de la position de cette référence sur la présence et l'ampleur de la NSU. La discussion porte sur les mécanismes liés à la prise d'informations et/ou à l'orientation de l'attention dans l'espace et leur implication dans la prise en charge et la rééducation de la NSU.

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Johansson, Falck Marlene. "From perception of spatial artefacts to metaphorical meaning." Umeå universitet, Institutionen för språkstudier, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-52535.

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This chapter compares spatial constructs in mental imagery to spatial constructs in non-metaphorical and metaphorical language. The study is based on a psycholinguistic survey of people’s mental imagery for paths and roads, and a previous corpus-linguistic investigation of path- and road-instances from the British National Corpus (the BNC) (see Johansson Falck 2010). The aim is to investigate if spatial path and road constructs in mental imagery focus on similar aspects as those in metaphorical language. The study shows that mental imagery and metaphorical language are more restricted than non-metaphorical language, and typically are related to the specific anticipations for bodily action that paths and roads afford. The focus is on function, which influences both direction and manner of motion.
Embodiment of Motion Metaphors

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Henrion, Andrea. "The urban observatory : spatial adjustment-perception in space." Virtual Press, 1997. http://liblink.bsu.edu/uhtbin/catkey/1116357.

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This thesis develops a creative Project, the "Urban Observatory", situated on a traffic island in the center of Chicago on Wacker Drive and Wabash Avenue along the Chicago River. The aim of the building is to inspire and motivate people to experience the city from a different standpoint and to raise the inhabitant of the city to a different level of perception.The purpose of this study was to explore everyday circumstances and observations of an individual place, the American City and the search for its true genius loci. The main intention is to explore and visualize issues about culturally based differences in behavior and perception of people living in place of 'super scale' and 'high technology' on one side and abandonment and destruction on the other side. The study of the American City and its inhabitants results in an experimental design for an Urban Observatory, an architectural formulation standing in opposition to an architecture of change and fragmentation, an architecture of lost and senseless space. Furthermore the study researches the urban American fabric in practice as well as in theory. The intensive study of the writings of Malcolm Quantrill, Richard Sennett, Toni Hiss and others were the base for developing ideas about how people perceive and react consciously and unconsciously to a specific environment.This helped to identify the frame of the architectural exploration, in order to focus on ideas about: what is architecture of observation in the urban context, and what is the idea of perception in its spatial form?A journal of the design process (sketches, writings), models of varying scale and detail, drawings, photographs, etc. are the working tools to shape the idea of a building and fusing all aspects in a final project.
Department of Architecture

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Riera, Robusté Joan. "Spatial hearing and sound perception in musical composition." Doctoral thesis, Universidade de Aveiro, 2014. http://hdl.handle.net/10773/13269.

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Doutoramento em Música
This thesis explores the possibilities of spatial hearing in relation to sound perception, and presents three acousmatic compositions based on a musical aesthetic that emphasizes this relation in musical discourse. The first important characteristic of these compositions is the exclusive use of sine waves and other time invariant sound signals. Even though these types of sound signals present no variations in time, it is possible to perceive pitch, loudness, and tone color variations as soon as they move in space due to acoustic processes involved in spatial hearing. To emphasize the perception of such variations, this thesis proposes to divide a tone in multiple sound units and spread them in space using several loudspeakers arranged around the listener. In addition to the perception of sound attribute variations, it is also possible to create rhythm and texture variations that depend on how sound units are arranged in space. This strategy permits to overcome the so called "sound surrogacy" implicit in acousmatic music, as it is possible to establish cause-effect relations between sound movement and the perception of sound attribute, rhythm, and texture variations. Another important consequence of using sound fragmentation together with sound spatialization is the possibility to produce diffuse sound fields independently from the levels of reverberation of the room, and to create sound spaces with a certain spatial depth without using any kind of artificial sound delay or reverberation.
Esta tese explora as possibilidades da Audição Espacial em relação à percepção do som e apresenta três composições acusmáticas baseadas numa estética musical que enfatiza esta relação e a incorpora como uma parte do seu discurso musical. A primeira característica importante destas composições é a utilização exclusiva de sinusóides e de outros sinais sonoros invariáveis no tempo. Embora estes tipos de sinais não apresentem variações no tempo, é possível percepcionar variações de altura, intensidade e timbre assim que estes se movem no espaço, devido aos processos acústicos envolvidos na audição espacial. Para enfatizar a percepção destas variações, esta tese propõe dividir um som em múltiplas unidades e espalhá-las no espaço utilizando vários monitores dispostos à volta da plateia. Além da percepção de variações de características do som, também é possível criar variações de ritmo e de textura que dependem de como os sons são dispostos no espaço. Esta estratégia permite superar o problema de “sound surrogacy” implícito na música acusmática, uma vez que é possível estabelecer relações causa-efeito entre o movimento do som e a percepção de variações de características do som, variações do ritmo e textura. Outra consequênça importante da utilização da fragmentação com a espacialização do som é a possibilidade de criar campos sonoros difusos, independentemente dos níveis de reverberação da sala, e de criar espaços sonoros com uma certa profundidade, sem utilizar nenhum tipo de delay ou reverberação artificiais.

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Bondugula, Rajkumar. "Capturing the user's perception of directional spatial relations /." free to MU campus, to others for purchase, 2003. http://wwwlib.umi.com/cr/mo/fullcit?p1418006.

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Dahl, Howard Stewart. "Comparison of spatial contrast sensitivity between younger and older observers." Thesis, University of British Columbia, 1985. http://hdl.handle.net/2429/25373.

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Contrast sensitivity to vertically oriented grating patterns with a sinusoidal luminance profile were examined between groups of observers varying either in gender or age. For each observer at each of the seven spatial frequencies tested (.75, 1.5, 3, 6, 7.5, 10, 15 cyc/deg) threshold values were calculated for either ascending or descending trials as well as a combination of both. These threshold values were numerically transformed into sensitivity values and contributed to a group mean contrast sensitivity score for each spatial frequency. No significant effect of gender was found but younger observers (mean age=22.6 yrs.) exhibited significantly better contrast sensitivity than the older aged group (mean age=66.2 yrs.) for ascending trials at 3, 1.5 and .75 cyc/deg--the lowest spatial frequencies tested. Contrast sensitivity was also correlated with various measures. These findings were discussed in relation to the existing literature on age and spatial contrast sensitivity and since the machine used to examine the contrast sensitivity function (CSF) in this study utilized a laser interferometric method of stimulus generation, possible neurological changes with aging to explain this noted loss were also considered. Also discussed were various parameters that effect the CSF with a view toward explaining the disparate findings of various existing studies of age and the CSF.
Arts, Faculty of
Psychology, Department of
Graduate

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Coker, Dianna Ross. "The role of visual-spatial aptitude in accounting coursework." Diss., This resource online, 1993. http://scholar.lib.vt.edu/theses/available/etd-06062008-170640/.

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Farran, Emily Kate. "Visuo-spatial cognition in Williams syndrome." Thesis, University of Bristol, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.390996.

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Geeseman, Joseph W. "The influence of auditory cues on visual spatial perception." OpenSIUC, 2010. https://opensiuc.lib.siu.edu/theses/286.

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Traditional psychophysical studies have been primarily unimodal experiments due to the ease in which a single sense can be isolated in a laboratory setting. This study, however, presents participants with auditory and visual stimuli to better understand the interaction of the two senses in visuospatial perception. Visual stimuli, presented as Gaussian distributed blobs, moved laterally across a computer monitor to a central location and "bounced" back to their starting position. During this passage across the screen, a brief auditory "click" was presented via headphones. Participants were asked to respond to the bounce of the ball, and response latency was recorded. Response latency to the bounce position varied as a function of baseline (no sound) and the varying sound offset locations.

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Best, Virginia Ann. "Spatial Hearing with Simultaneous Sound Sources: A Psychophysical Investigation." University of Sydney. Medicine, 2004. http://hdl.handle.net/2123/576.

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This thesis provides an overview of work conducted to investigate human spatial hearing in situations involving multiple concurrent sound sources. Much is known about spatial hearing with single sound sources, including the acoustic cues to source location and the accuracy of localisation under different conditions. However, more recently interest has grown in the behaviour of listeners in more complex environments. Concurrent sound sources pose a particularly difficult problem for the auditory system, as their identities and locations must be extracted from a common set of sensory receptors and shared computational machinery. It is clear that humans have a rich perception of their auditory world, but just how concurrent sounds are processed, and how accurately, are issues that are poorly understood. This work attempts to fill a gap in our understanding by systematically examining spatial resolution with multiple sound sources. A series of psychophysical experiments was conducted on listeners with normal hearing to measure performance in spatial localisation and discrimination tasks involving more than one source. The general approach was to present sources that overlapped in both frequency and time in order to observe performance in the most challenging of situations. Furthermore, the role of two primary sets of location cues in concurrent source listening was probed by examining performance in different spatial dimensions. The binaural cues arise due to the separation of the two ears, and provide information about the lateral position of sound sources. The spectral cues result from location-dependent filtering by the head and pinnae, and allow vertical and front-rear auditory discrimination. Two sets of experiments are described that employed relatively simple broadband noise stimuli. In the first of these, two-point discrimination thresholds were measured using simultaneous noise bursts. It was found that the pair could be resolved only if a binaural difference was present; spectral cues did not appear to be sufficient. In the second set of experiments, the two stimuli were made distinguishable on the basis of their temporal envelopes, and the localisation of a designated target source was directly examined. Remarkably robust localisation was observed, despite the simultaneous masker, and both binaural and spectral cues appeared to be of use in this case. Small but persistent errors were observed, which in the lateral dimension represented a systematic shift away from the location of the masker. The errors can be explained by interference in the processing of the different location cues. Overall these experiments demonstrated that the spatial perception of concurrent sound sources is highly dependent on stimulus characteristics and configurations. This suggests that the underlying spatial representations are limited by the accuracy with which acoustic spatial cues can be extracted from a mixed signal. Three sets of experiments are then described that examined spatial performance with speech, a complex natural sound. The first measured how well speech is localised in isolation. This work demonstrated that speech contains high-frequency energy that is essential for accurate three-dimensional localisation. In the second set of experiments, spatial resolution for concurrent monosyllabic words was examined using similar approaches to those used for the concurrent noise experiments. It was found that resolution for concurrent speech stimuli was similar to resolution for concurrent noise stimuli. Importantly, listeners were limited in their ability to concurrently process the location-dependent spectral cues associated with two brief speech sources. In the final set of experiments, the role of spatial hearing was examined in a more relevant setting containing concurrent streams of sentence speech. It has long been known that binaural differences can aid segregation and enhance selective attention in such situations. The results presented here confirmed this finding and extended it to show that the spectral cues associated with different locations can also contribute. As a whole, this work provides an in-depth examination of spatial performance in concurrent source situations and delineates some of the limitations of this process. In general, spatial accuracy with concurrent sources is poorer than with single sound sources, as both binaural and spectral cues are subject to interference. Nonetheless, binaural cues are quite robust for representing concurrent source locations, and spectral cues can enhance spatial listening in many situations. The findings also highlight the intricate relationship that exists between spatial hearing, auditory object processing, and the allocation of attention in complex environments.

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Ralston, George Eastop. "Visuo-spatial working memory." Thesis, University of St Andrews, 1988. http://hdl.handle.net/10023/9595.

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This study set out to investigate the visuo-spatial component of Baddeley and Hitch's (1974) Working Memory framework. The development of our understanding of this component has been less dramatic than that of its verbal counterpart, the Articulatory Loop. The primary reason for this can be said to be the lack of techniques for investigation (Logie, 1986). This thesis presents one attempt to try to explore the nature of this code and to reveal possible new techniques of investigation. The following are three possible areas of investigation : 1. Is the system spatially or visually based? 2. Does movement have a role in the system? 3. How is information stored? The latter two issues are investigated here. Experiments 1-4 set out to explore the possibility that movement may be involved in the code. These experiments supported the idea that movement has a role to play in spatial coding and more specifically demonstrated that arm movements which are not compatible with the presentation of spatial material can cause disruption. In addition it was shown that when movement identical to that involved in presentation is encouraged at recall subjects show marked improvement in performance. Together these results very strongly suggest that movement should be given prominent reference in the definition of spatial coding and in the description of the visuo-spatial slave system. Another development that came out of these experiments relates to the lack of investigative techniques in the field of visuo-spatial short term memory. The fact that movement has been shown to be important suggests that techniques employed to investigate kinaesthetic memory will aid us in exploring visuo-spatial coding. The second issue in this thesis explored further the nature of the internal code. Research into the nature of coding in visuo-spatial memory had previously argued for the presence of a sequential component. Experiments 1-4 in this thesis had shown that movement had an important role to play in coding. The fact that movement by its very nature would appear to be sequential suggested that there was a strong sequential element in coding within visuo-spatial memory. However, concern was expressed that the materials and presentation format used may have led to sequential coding. This was first explored in experiments 5-8. The results supported the view that the material and presentation format used had led to sequential coding. This was further explored by Experiments 9 and 10 which illustrated that while it may be important under certain conditions, sequentiality is not always a dominant element in coding within the Visuo-Spatial Sketch Pad. This thesis has explored two of the central issues currently interesting theorists of Working Memory and has put forward suggestions for techniques which may in the future help us to advance our knowledge of the visuo-spatial component of the Working Memory framework.

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Fabrigoule, Colette. "Etude des processus cognitifs impliqués dans l'apprentissage spatial chez le chien et le renard." Aix-Marseille 2, 1987. http://www.theses.fr/1987AIX22060.

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En milieu naturel les renards manifestent une grande variabilite de deplacements a l'interieur de leur domaine. Cette variabilite de trajets est beaucoup plus compatible avec la theorie cognitive selon laquelle les animaux reorganisent les informations collectees dans le milieu qu'avec la theorie behavioriste qui affirme que les animaux acquierent les habitudes locomotrices. Les chiens, confrontes a des situations de recherche libre de nourriture, montrent egalement une grande variabilite de trajets. Ils sont capables de reorganisation et d'integration de l'information collectee

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Helmetag, Arnd. "Improvement of perception and cognition in synthetic spatial environments." [S.l.] : [s.n.], 2000. http://elib.tu-darmstadt.de/diss/000130/Helm2.pdf.

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Craven, Benjamin Joseph. "Saccadic undershoot and the perception of lateral spatial extent." Thesis, University of Cambridge, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.302947.

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Cleary, Robert. "Spatial frequency selective processes in short range motion perception." Thesis, University of Cambridge, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.237562.

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Newman, Michael C. (Michael Charles). "A multisensory observer model for human spatial orientation perception." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/51636.

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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Aeronautics and Astronautics, 2009.
Includes bibliographical references (p. 37-41).
Quantitative "observer" models for spatial orientation and eye movements have been developed based on 1-G data from humans and animals (e.g. Oman 1982, 1991, Merfeld, et al 1993, 2002; Haslwanter 2000, Vingerhoets 2006). These models assume that the CNS estimates "down", head angular velocity and linear acceleration utilizing an internal model for gravity and sense organ dynamics, continuously updated by sensory-conflict signals. CNS function is thus analogous to a Luenberger state observer in engineering systems. Using a relatively small set of free parameters, Observer orientation models capture the main features of experimental data for a variety of different motion stimuli. We developed a Matlab/Simulink based Observer model, including Excel spreadsheet input capability and a GUI to make the model accessible to less expert Matlab users. Orientation and motion predictions can be plotted in 2D or visualized in 3D using virtual avatars. Our Observer's internal model now computes azimuth, and pseudointegrates linear motion in an allocentric reference frame (perceived north-east-down). The model mimics the large perceptual errors for vertical motion observed experimentally. It retains the well validated "vestibular core" of the Merfeld perceptual model and predicts responses to angular velocity and linear accelerations steps, dumping, fixed radius centrifugation, roll tilt and OVAR. This model was further extended to include static and dynamic visual sensory information from four independent visual sensors (Visual Velocity, Position, Angular Velocity and Gravity/"Down").
(cont.) Visual additions were validated against the Borah et al (1978) Kalman filter simulation results and validation data sets (Earth vertical constant velocity rotation in the light, somatogravic illusion in the light, and linear and circular vection). The model predicts that circular vection should have two dynamic components, and the recent finding of Tokumaru et al (1998) that visual cues influence somatogravic illusion in ways not accounted for by the Borah model. The model also correctly predicts both the direction of Coriolis illusion, and the magnitude of the resulting tilt illusion. It also predicts that the direction and mechanism of Pseudo-Coriolis illusion is fundamentally different from Coriolis, a prediction verified by means of a pilot experiment. Finally, the model accounts for the dynamics of astronaut post-flight tilt-gain and OTTR vertigos in ways not explained by previous static analyses (e.g. Merfeld, 2003). Supported by the National Space Biomedical Research Institute through NASA NCC 9-58.
by Michael C. Newman.
S.M.

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FARCET, NICOLAS. "Perception et filtrage spatial dans les environnements virtuels distribues." Paris 6, 1999. http://www.theses.fr/1999PA066182.

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La realite virtuelle distribuee designe des applications multi-sites et multi-participants qui sont utilisables au travers d'interfaces graphiques tridimensionnelles. Ces applications permettent aux participants d'interagir de maniere realiste et intuitive avec des environnements, essentiellement synthetises par ordinateur, qui symbolisent ou reproduisent le lieu et les constituants d'une tache generalement collaborative. Dans ces environnements virtuels, l'espace permet une representation moins discontinue de l'information, ameliorant ainsi le sentiment de presence des participants. Le modele d'information qui decrit l'environnement virtuel partage est en majeure partie duplique sur les sites participant a son execution. Pour maintenir la coherence entre les parties dupliquees de ce modele, il est necessaire de diffuser a l'ensemble des sites les actions issues d'un site particulier. Cette diffusion cree cependant sur le reseau un trafic important d'information de coherence. La bande passante limitee du reseau tend a limiter en taille et en complexite les environnements virtuels partages. Afin d'ameliorer la capacite des systemes de realite virtuelle distribues a monter en charge, nous nous sommes interesses a des techniques permettant de filtrer le trafic reseau. Nous sommes partis du constat que l'information reelle qui circule entre les sites sur le reseau provient pour la plus grande partie des interactions de perception a caractere spatial entre les entites de l'environnement virtuel. Nous avons developpe une technique de filtrage distribue qui s'appuie sur une structuration de l'environnement virtuel selon ses dimensions d'espace et d'echelle. Cette structuration permet de mettre en uvre efficacement une fonction de filtrage spatial basee sur la perception des entites de l'environnement virtuel.

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Henry, Daniel. "Spatial perception in virtual environments : evaluating an architectural application /." Connect to this title online (HTML format) Connect to this title online (PDF format) Connect to this title online (PostScript format) Connect to this title online (self-extracting binhexed format), 1992. http://www.hitl.washington.edu/publications/henry/.

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Braem, Bérenger. "Perception des orientations et intégration multisensorielle." Thesis, Lille 3, 2014. http://www.theses.fr/2014LIL30010/document.

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La perception de la verticale repose sur l’intégration des informations vestibulaires, visuelles et somesthésiques. Elle est généralement étudiée dans la modalité visuelle (VVS) ou haptique (VHS) et plus rarement dans la modalité visuo-haptique (VVHS). Cette modalité pose la question de l’intégration des informations mises en jeu par ces deux modalités dans la perception multimodale et du modèle cognitif sous-jacent. Se pose également la question de l'effet des lésions cérébrales perturbant la perception spatiale (hémi-négligence) dans la perception de la verticale.Une comparaison des VVS, VHS et VVHS est réalisée dans les quatre premières études de cette thèse, chez des participants sains jeunes et plus âgés et chez des patients cérébro-lésés droits avecou sans troubles visuo-spatiaux. Les performances observées sont proches de la verticale gravitaire chez les participants sains pour les VVS et VVHS. La VHS (avec la main droite) est déviée, dans le sens horaire chez les jeunes participants et anti-horaire pour les participants plus âgés. La présence d’un cadre visuel perturbe les VVS et VVHS chez les participants dépendants à l'égard du champ.Les patients cérébro-lésés droits présentent une déviation anti-horaire des trois verticales, plus marquée pour la VHS. Les VVHS mesurées sont correctement prédites, dans toutes les conditions,par la somme des VVS et VHS pondérées par leurs précisions relatives. La variance de la VVHS est moindre que les variances des VVS et VHS. La VHS, systématiquement déviée dans ces quatre premières études, fait l’objet d’une évaluation détaillée dans les deux dernières études de cette thèse. Les résultats montrent que la VHS est déviée dans le sens horaire avec la main droite, dans le sens anti-horaire avec la main gauche chez les participants sains jeunes ; les déviations s’inversent avec l’âge. Par ailleurs, les performances sont systématiquement déviées dans le sens des positions initiales. Considérés ensemble, ces résultats montrent que la perception de la verticale implique les informations mises en jeu par les modalités visuelle et haptique mais avec une prépondérance de la première. Ce travail de thèse montre ainsi que la perception de la verticale subjective repose sur une intégration multimodale pondérée des informations sensorielles en accord avec le modèle statistique bayésien du maximum de vraisemblance. Ce mode d'intégration multi-sensorielle n'est pas altéré par l’âge ou la présence de lésions cérébrales affectant la perception visuo-spatiale. Plusieurs pistes restent à explorer, notamment, le poids de la contribution des informations vestibulaires dans la verticale subjective
The perception of the vertical direction is achieved through vestibular, visual and somatosensory information integration. It is studied in the visual (SVV), haptic (SHV) and less often in the visuo-haptic modality (SVHV). The latter raises the question of the integration of visual the information involved in the visual and haptic modalities and of the cognitive model underlying this integration. SVV, SHV and SVHV were compared in the first four studies of this thesis, inhealthy young and older subjects and in right-brain damaged patients with or without visuo-spatial disorders. Performances were closed to the gravity in healthy participants, for SVV as well as forSVHV. VHS, assessed with the right hand, was tilted clockwise in young participants and anticlockwise in older participants. The presence of a visual frame disrupted SVV and SVHV. The right-brain damaged patients had an anti-clockwise deviation of SVV and SVHV and the SHV was even more tilted. SVHV was well predicted from the sum of the SVV and SHV weighted by their relative variances in all conditions and the SVHV variances were lesser. SHV was evaluated in detail in the two last studies of this thesis because of the systematic tilt in the first four studies. The results show that the SHV is tilted clockwise with the right hand and anti-clockwise with the left hand in young healthy subjects. Moreover, deviations reversed in older group and performances are systematically tilted toward the initial positions in the two groups. Taken together, these results show that the way participants integrate visual and haptic information fits the maximum like lihoodmodel with a greater weighting of information available in visual modality and that ageing and right-brain lesions does not alter the multisensory integration. The weight of vestibular information in the subjective vertical, which has not been evaluated per se in this thesis, needs further investigations

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DuBois, Jennifer Faith. "Spatial and Temporal Changes in Tsunami Risk Perception in Canterbury." Thesis, University of Canterbury. Geological Sciences, 2007. http://hdl.handle.net/10092/1440.

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Risk perception for rare, low-probability hazards, such as tsunamis, tends to be low due to individual's unfamiliarity with them and the tendency to see them as synonymous with non-occurrence events. Visitors to an area tend to have even lower risk perception and knowledge of hazards, warning systems and appropriate actions to take during an event. Risk perception, however, can increase, if only temporarily, after a catastrophic event, such as the 2004 Boxing Day tsunami. To determine the changes in resident's knowledge and perception and the differences between those of residents and visitors two surveys were conducted. In the first survey interview style surveying was conducted at eleven locations in the coastal Christchurch and Banks Peninsula area of the Canterbury Region The questionnaire was composed of scaled, open, and closed ended questions and the main themes included knowledge of risk, preparation and warnings, what to do during a tsunami, and changes since the 2004 Boxing Day tsunami. The second survey of five coastal communities was conducted via a postal questionnaire and was aimed at obtaining residential views. Survey data was then analysed with Statistical Package for the Social Sciences (SPSS) statistical software. The residential data was compared with that of the non-residents to determine the differences in perception of residents and visitors. The residential information was then compared with survey data from the 2003 National Coastal Survey. Visitors knew less about general tsunami information such as when the last tsunami occurred and were less likely to believe that a tsunami could occur imminently. Non-residents reported less receipt of information and did considerably less information seeking. Differences in knowledge of warning systems were difficult to ascertain. The Boxing Day event certainly made an impact, increasing people's knowledge and awareness, though most likely only temporarily.

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Jin, Craig T. "Spectral analysis and resolving spatial ambiguities in human sound localization." Connect to full text, 2001. http://hdl.handle.net/2123/1342.

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Thesis (Ph. D.)--School of Electrical and Information Engineering, Faculty of Engineering, University of Sydney, 2001.
Title from title screen (viewed 13 January 2009). Submitted in fulfilment of the requirements for the degree of Doctor of Philosophy to the School of Electrical and Information Engineering, Faculty of Engineering. Includes bibliographical references. Also available in print form.

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Cogné, Mélanie. "Influence de modulations sensorielles sur la navigation et la mémoire spatiale en réalité virtuelle : Processus cognitifs impliqués." Thesis, Bordeaux, 2017. http://www.theses.fr/2017BORD0704.

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Se déplacer selon un but déterminé est une activité courante de la vie quotidienne. Des capacités cognitives variées sont associées aux déplacements, comme la navigation, la mémoire ou encore l’orientation spatiale. De nombreux patients cérébro-lésés ou atteints par une maladie neuro-dégénérative présentent des difficultés topographiques qui retentissent sur leur autonomie en vie quotidienne. Les outils de réalité virtuelle permettent d’évaluer la navigation et la mémoire spatiale à grande échelle, avec une bonne corrélation entre cette évaluation et celle qui serait réalisée dans un environnement réel. La réalité virtuelle permet également d’ajouter des stimuli à la tâche proposée. Ces stimuli additionnels peuvent être contextuels, c’est à dire reliés à la tâche à réaliser dans l’environnement virtuel, ou noncontextuels, soit sans lien avec la tâche à accomplir. Ce travail de thèse s’est attaché à évaluer l’impact de stimuli auditifs et visuels sur la navigation et la mémoire spatiale de patients cérébro-lésés ou présentant une maladie neuro-dégénérative, dans des expériences de réalité virtuelle. Les deux premiers volets de cette thèse ont étudié l’effet de stimuli auditifs contextuels ou non-contextuels lors d’une tâche de courses au sein du supermarché virtuel VAP-S. Le premier volet a montré que des stimuli auditifs contextuels de type effet sonar et énoncé du nom du produit facilitaient la navigation spatiale de patients cérébro-lésés impliqués dans cette tâche de courses. Le second volet a mis en évidence que des sons non-contextuels avec une importante saillance cognitive ou perceptuelle péjoraient la performance de navigation de patients ayant présenté un accident vasculaire cérébral. Les deux volets suivants de cette thèse ont étudié l’effet d’indiçages visuels ou auditifs dans une tâche de navigation spatialedans un quartier virtuel. Ainsi, le troisième volet de la thèse a démontré que des indices visuels comme des flèches directionnelles ou des points de repère sursignifiés facilitaient la navigation spatiale et certains aspects de mémoire spatiale de patients avec des troubles cognitifs légers (MCI) ou présentant une Maladie d’Alzheimer. Enfin, le quatrième volet a mis en évidence qu’un indiçage auditif par des bips indiquant la direction à chaque intersection améliorait la navigation spatiale de patients cérébro-lésés droits présentant une héminégligence visuelle et auditive controlatérale. Ces résultats suggèrent que des stimuli auditifs et visuels pourraient être utilisés lors de prises en charge rééducatives et réadaptatives de patients présentant des difficultés topographiques, ainsi qu’en vie quotidienne par le biais de la réalité augmentée afin de faciliter leurs déplacements. L’impact des stimuli chez les sujets sains et chez les cérébrolésés est différent et justifie une analyse spécifique de processus probablement distincts impliqués lors des déficits cognitifs
Navigating in a familiar or unfamiliar environment is a frequent challenge for human beings. Many patients with brain injury suffer from topographical difficulties, which influences their autonomy in daily life. Virtual Reality Tools enable the evaluation of largescale spatial navigation and spatial memory, resembling a real environment. Virtual reality also permits to add stimuli to the software. These stimuli can be contextual, that is to say linked to the task that participants have to accomplish in the Virtual Environment, or non-contextual, i.e. with no link with the require task. This thesis investigates whether visual or auditory stimuli influence spatial navigation and memory in Virtual Environments of patients with brain injury or with a neurodegenerative disease. The first part of the thesis showed contextual auditory stimuli type a sonar effect and the names of products of the shopping list improved spatial navigation of brain-injured patients during a shopping task in the virtual supermarket VAP-S. The second part of this thesis highlighted that non-contextual auditory stimuli with a high perceptual or cognitive salience decreased spatial navigation performance of brain-injured patients during a shopping task in the VAP-S. The third part of this thesis showed that visual cues like directional arrows and salient landmarks improved spatial navigation and some aspects of spatial memory of patients with Alzheimer’s disease or Mild Cognitive Impairments during a navigation task in a virtual district. The last part of this thesis demonstrated that auditory cues, i.e. beeping sounds indicating the directions, increased spatial navigation in a virtual district of patients who have had a stroke with contra-lesional visual and auditory neglect. These results suggest that some visual and auditory stimuli could be helpful for spatial navigation and memory tasks in patients with brain injury of neuro-degenerative disease. It further offers new research avenues for neuro-rehabilitation, such as the use of augmented reality in real-life settings to support the navigational capabilities of these patients

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Rainville, Stéphane Jean Michel. "The spatial mechanisms mediating the perception of mirror symmetry in human vision /." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=36688.

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The present thesis reports psychophysical and modeling studies on the spatial properties of visual mechanisms mediating the perception of mirror symmetry in human vision. In a first set of experiments, patterns were filtered for power spectra that decayed with spatial frequency according to variable slopes. Results revealed that symmetry detection is optimal if contrast energy is roughly equated across log-frequency bands (i.e. 1/f2) and that, under such conditions, spatial scales contribute equally and independently to symmetry perception. In a second study, random-noise patterns were filtered for various orientation bands. Results showed that symmetry perception is possible at all orientations, is mediated by oriented mechanisms, and is computed independently in different orientation channels. Data also revealed that the dimensions of the spatial integration region (IR) for symmetry vary with orientation in a way that approximately matches the spatial distribution of information in the stimulus. Finally, symmetry detection was measured for bandpass textures of variable spatial density and variable contrast polarity. For such patterns, it was found that symmetry is computed at a spatial scale proportional to stimulus density and that mechanisms insensitive to contrast polarity (i.e. second-order) are involved in the scale-selection process.
Overall, results from empirical and modeling work revealed an intimate link between symmetry perception and the properties of spatial filters. In particular, I argue that the size of the IR tends to vary such that a fixed amount of information is integrated irrespective of the spatial properties of the stimulus. Implications for the functional architecture of symmetry perception are discussed, and a paradigm for future research in symmetry perception is proposed in which spatial filtering is extended to higher orders of spatial complexity.

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Loach, Daniel. "Inhibitory processes in temporal selection." Thesis, Bangor University, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.275136.

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Save, Etienne. "Rôle du cortex pariétal associatif dans l'élaboration et l'utilisation des représentations spatiales chez le rat : comparaison avec l'hippocampe." Aix-Marseille 3, 1993. http://www.theses.fr/1993AIX30029.

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L'hypothese d'une organisation hierarchisee des representations spatiales chez le rat trouve un echo dans la diversite des strategies comportementales mises en uvre par les animaux, dans les taches d'apprentissage spatial. Cette diversite pourrait refleter l'intervention de differentes structures nerveuses. Or, depuis une vingtaine d'annees, l'hippocampe est considere comme etant le substrat neuro-anatomique des processus impliques dans l'elaboration des cartes cognitives et dans la memoire spatiale. Cette theorie a ete moderee par des donnees recentes qui suggerent que le cortex parietal associatif (cpa) jouerait un role important dans ces processus. Nos resultats, reposant principalement sur l'analyse des effets de lesions de l'hippocampe et du cpa sur l'habituation et la reaction au changement au cours de l'exploration, confirment la fonction spatiale du cpa. Ils suggerent d'autre part, en accord avec les donnees neuroanatomiques, que le cpa prendrait en charge plusieurs fonctions. En particulier, il interviendrait a une etape precoce du traitement des informations spatiales (transformation des informations d'origine sensorielle). Par ailleurs, cette transformation serait regulee par des processus attentionnels permettant de selectionner les informations pertinentes a la realisation de la tache. Enfin, il jouerait un role dans le stockage des informations en memoire a long terme. Dans l'ensemble, les donnees suggerent que le cpa et l'hippocampe interagissent etroitement et constituent une boucle fonctionnelle dont le role est crucial dans le codage et le stockage des informations spatiales

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Ackroyd, Katie Elizabeth. "The contribution of neuropsychology to the understanding of depth perception." Thesis, University of Birmingham, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.273940.

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Blanc-Goldhammer, Daryn. "The Neural and Perceptual Mechanisms Underlying Spatial Integration." Thesis, University of Oregon, 2019. http://hdl.handle.net/1794/24536.

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The visual system integrates information over space to see surfaces, contours and edges. This integration can be described by a divisive normalization framework in which surrounding contextual information normalizes response to a central target. We ran a set of studies examining perceptual illusions with the intention of better understanding the neural mechanisms responsible for how the visual system integrates information over space. We measured surround integration using the Simultaneous Tilt Illusion. In the first study, we determined the extent to which the probability that different surround regions were co-assigned to the same object as the center impacts how much they are integrated. We found that the magnitude of the illusion was a sum of regional surround effects weighted by their dependency to the center. These results are consistent with a system that uses prior experience with natural scene statistics to integrate regions of space. In the second study, we measured the relationship between individual differences in spatial integration and autistic traits. We found no evidence for reduced normalization in people who score high on autistic traits. In the third study, we determined the extent to which arousal modulates spatial integration. Although we did not observe an effect of natural fluctuations in arousal, as indexed by pupil diameter, we observed a reduction in the magnitude of the illusion following an alerting tone. While more work is still needed to verify this effect, it suggests that we context information less under moderately alert states. We interpret these results in the context of the neural and perceptual mechanisms underlying spatial integration. Specifically, these results seem to indicate that the normalization process is gated by our expectancies about the structure of a scene and by our internal brain state. These results are consistent with a system that uses prior experience with scene statistics to represent patterns more efficiently.

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Kempster, Kurt A. "Frame rate effects on human spatial perception in video intelligence." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2000. http://handle.dtic.mil/100.2/ADA382287.

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Thesis (M.S. in Information Technology Management) Naval Postgraduate School, Sept. 2000.
"September 2000." Thesis advisor(s): Darken, Rudolph P.; Brady, Terrance C. Includes bibliographical references (p. 77-78). Also available online.

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Mehta, Samar Bharat. "Sensorimotor integration and spatial perception in the rat vibrissa system." Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2006. http://wwwlib.umi.com/cr/ucsd/fullcit?p3211936.

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Thesis (Ph. D.)--University of California, San Diego, 2006.
Title from first page of PDF file (viewed June 21, 2006). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 103-113).

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Wiener, Jan M. "Places and regions in perception, route planning and spatial memory." Tübingen, Robert-Grandmann-Weg 3 : J. M. Wiener, 2004. http://deposit.ddb.de/cgi-bin/dokserv?idn=971944148.

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James, David. "The spatial imaginary of contemporary British fiction : place, perception, poetics." Thesis, University of Sussex, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.426265.

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Dissertations / Theses on the topic 'Spatial perception'

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