Academic literature on the topic 'Spatial-temporal disorders'

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Journal articles on the topic "Spatial-temporal disorders"

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Casarrubias-Jaimez, Ana I., Ana Laura Juárez-López, Efraín Tovar-Sánchez, José Luis Rosas-Acevedo, Maximino Reyes-Umaña, América Libertad Rodríguez-Herrera, and Fernando Ramos-Quintana. "Dealing with the Understanding of the Dynamics Related to Multifactorial Temporal Interactions That Spatially Affect the Landscape of Coastal Lagoons." Water 13, no. 15 (July 31, 2021): 2099. http://dx.doi.org/10.3390/w13152099.

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Models based on multifactorial interactions are needed to deal with the dynamics taking place in the eutrophication processes of coastal lagoons. However, as the number of indirect drivers stemming from anthropogenic factors increases, temporal disorders between anthropogenic activities may increase, thus hindering the understanding of their dynamics. We have built multifactorial pathways to deal with the dynamics associated with the cultural eutrophication process of a coastal lagoon. The pathways guided the identification of potential temporal disorder patterns between anthropogenic activities, which may exert influence on the disturbances associated with eutrophication process. The identification of temporal disorder patterns derived from anthropogenic activities belonging to different pathways resulted in a valuable form of support for analyzing and evaluating relationships between public policies, technological skills and environmental culture programs. All of which exert influence on the eutrophication process, which in turn cause changes on the trophic state and on the landscape of the coastal lagoon. Pathways composed of multifactorial interactions that take into account spatial and temporal aspects, contribute to improving the understanding of the inherent dynamics of the eutrophication process of coastal lagoons. Temporal disorders between anthropogenic activities may be seen to emerge, thus exerting changes on the trophic state and spatial damage on the landscapes of coastal lagoons.
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Usov, Konstantin. "SYNDROMES OF TPO LESION AND SPATIAL FACTOR DISORDERS IN MENTAL PROCESSES." Modern Technologies and Scientific and Technological Progress 2022, no. 1 (May 16, 2022): 283–84. http://dx.doi.org/10.36629/2686-9896-2022-1-283-284.

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Buhusi, Mona, Ioana Scripa, Christina L. Williams, and Catalin V. Buhusi. "Impaired Interval Timing and Spatial–Temporal Integration in Mice Deficient in CHL1, a Gene Associated with Schizophrenia." Timing & Time Perception 1, no. 1 (2013): 21–38. http://dx.doi.org/10.1163/22134468-00002003.

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Interval timing is crucial for decision-making and motor control and is impaired in many neuropsychiatric disorders, including schizophrenia — a neurodevelopmental disorder with a strong genetic component. Several gene mutations, polymorphisms or rare copy number variants have been associated with schizophrenia. L1 cell adhesion molecules (L1CAMs) are involved in neurodevelopmental processes, and in synaptic function and plasticity in the adult brain. Mice deficient in the Close Homolog to L1 (CHL1) adhesion molecule show alterations of hippocampal and thalamo-cortical neuroanatomy as well as deficits in sensorimotor gating and exploratory behavior. We analyzed interval timing and attentional control of temporal and spatial information in male CHL1 deficient (KO) mice and wild type (WT) controls. In a 20-s peak-interval timing procedure (standard and reversed), KO mice showed a maintained leftward shift of the response function relative to WT, indicative of a deficit in memory encoding/decoding. In trials with 2, 5, or 10-s gaps, KO mice shifted their peak times less than WT controls at longer gap durations, suggesting a decreased (attentional) effect of interruptions. In the spatial–temporal task, KO mice made more working and reference memory errors than controls, suggestive of impaired use of spatial and/or temporal information. When the duration spent on the central platform of the maze was manipulated, WT mice showed fewer spatial errors at the trained duration than at shorter or longer durations, indicative of discrimination based upon spatial–temporal integration. In contrast, performance was similar at all tested durations in KO mice, indicative of control by spatial cues, but not by temporal cues. These results suggest that CHL1 KO mice selectively attend to the more relevant cues of the task, and fail to integrate more complex spatial–temporal information, possibly as a result of reduced memory capacity related to hippocampal impairment, and altered temporal-integration mechanisms possibly due to thalamo-cortical anomalies.
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Lopez, C., C. Hemimou, and L. Vaivre-Douret. "Handwriting disorders in children with developmental coordination disorder (DCD): Exploratory study." European Psychiatry 41, S1 (April 2017): S456. http://dx.doi.org/10.1016/j.eurpsy.2017.01.494.

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IntroductionAlthough more than 85% of children with DCD are affected by handwriting disorders, their characteristics and underlying mechanisms remain poorly known.ObjectivesWe aim to better identify the nature of handwriting disorders in subtyping DCD children.MethodsSchool children aged between 5 to 15 years and exhibited a DCD (according to DSM-5) are eligible for inclusion. They were classified in three subtypes of DCD: ideomotor (IM), visual-spatial and/or constructional (VSC), and mixed (MX). They were assessed with a standardized handwriting evaluation including quality and speed and a clinical observation of motor gestual developmental and temporal-spatial organization of handwriting highlighting six qualitative criteria: irregular handwriting (criterion 1), immaturity of handwriting gesture (criterion 2), excessive pressure of the pen on the paper (criterion 3), neuro-vegetative responses (criterion 4), trembling (criterion 5), slow handwriting velocity (criterion 6). Two groups are established: children with poor handwriting (PH) and children with dysgraphia (DysG).ResultsWhile 89% of children have handwriting disorders, only 20% exhibit dysgraphia. IM DCD is characterized by an immaturity of handwriting gesture and is associated with PH. Dysgraphia appears only in VSC and MX DCD which are characterized by the association of criteria 1, 2, 3, and 4. This association appears to more than 80% in DysG. Slow handwriting velocity is constant between PH and DysG.ConclusionImmaturity of handwriting gesture is a possible underlying mechanism of poor handwriting. Dysgraphia is associated with specific impairments in spatial organization of letters and in motor control of handwriting gesture.Disclosure of interestThe authors have not supplied their declaration of competing interest.
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Kwon, Hyeokhyen, Gari D. Clifford, Imari Genias, Doug Bernhard, Christine D. Esper, Stewart A. Factor, and J. Lucas McKay. "An Explainable Spatial-Temporal Graphical Convolutional Network to Score Freezing of Gait in Parkinsonian Patients." Sensors 23, no. 4 (February 4, 2023): 1766. http://dx.doi.org/10.3390/s23041766.

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Freezing of gait (FOG) is a poorly understood heterogeneous gait disorder seen in patients with parkinsonism which contributes to significant morbidity and social isolation. FOG is currently measured with scales that are typically performed by movement disorders specialists (i.e., MDS-UPDRS), or through patient completed questionnaires (N-FOG-Q) both of which are inadequate in addressing the heterogeneous nature of the disorder and are unsuitable for use in clinical trials The purpose of this study was to devise a method to measure FOG objectively, hence improving our ability to identify it and accurately evaluate new therapies. A major innovation of our study is that it is the first study of its kind that uses the largest sample size (>30 h, N = 57) in order to apply explainable, multi-task deep learning models for quantifying FOG over the course of the medication cycle and at varying levels of parkinsonism severity. We trained interpretable deep learning models with multi-task learning to simultaneously score FOG (cross-validated F1 score 97.6%), identify medication state (OFF vs. ON levodopa; cross-validated F1 score 96.8%), and measure total PD severity (MDS-UPDRS-III score prediction error ≤ 2.7 points) using kinematic data of a well-characterized sample of N = 57 patients during levodopa challenge tests. The proposed model was able to explain how kinematic movements are associated with each FOG severity level that were highly consistent with the features, in which movement disorders specialists are trained to identify as characteristics of freezing. Overall, we demonstrate that deep learning models’ capability to capture complex movement patterns in kinematic data can automatically and objectively score FOG with high accuracy. These models have the potential to discover novel kinematic biomarkers for FOG that can be used for hypothesis generation and potentially as clinical trial outcome measures.
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BĂLĂNEAN, DENISA, EUGEN BOTA, and SIMONA PETRACOVSCHI. "CORRECTION OF LEARNING DISORDERS BY OPTIMIZING THE DEVELOPMENT OF SPATIAL AND TEMPORAL ORIENTATION." Studia Universitatis Babeş-Bolyai Educatio Artis Gymnasticae 66, no. 2 (June 30, 2021): 43–66. http://dx.doi.org/10.24193/subbeag.66(2).15.

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Learning to read, write and calculate are proving to be some of the most significant cognitive processes in early education. The objective of this systematic review is to explore the associations between the psychomotor component and the academic achievement in writing, reading, and mathematics. An organized and methodical research of electronic databases was completed in order to determine significant studies. Twenty eligible articles were strictly evaluated, with extracted and summarized keywords. The two components of the psychomotor activity that influence reading were primarily the orientation ability and the fine motor skill, which is the one responsible for the correct spelling of “mirror-writing”. Differences in motor function were observed after intervention programmes. The results of all researchers have shown that there is a link between dysgraphia, dyslexia and the orientation ability or visual perception. Meanwhile, the role of cognitive and motor skills that underpinned mathematical performance was highlighted, and children who had a high capacity for spatial and visual orientation benefited from a better understanding and perception of geometric figures. However, the importance of students'''' spatial reasoning in relation to mathematics was identified, but only in terms of geometry. Poor quality of spatial notions has been found to be one of the causes of delay in the acquisition of reading, writing and mathematical calculation. The role of fine motor skills in the writing process was also noted, being of real importance in times when the child manipulates the writing tool and puts a word or a sentence on the page.
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Bucci, Maria Pia, Nathalie Goulème, Coline Stordeur, Eric Acquaviva, Isabelle Scheid, Aline Lefebvre, Christophe‐Loïc Gerard, Hugo Peyre, and Richard Delorme. "Discriminant validity of spatial and temporal postural index in children with neurodevelopmental disorders." International Journal of Developmental Neuroscience 61, no. 1 (July 3, 2017): 51–57. http://dx.doi.org/10.1016/j.ijdevneu.2017.06.010.

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Lopez, C., and L. Vaivre-Douret. "Effect of the vision suppression on the graphomotor gesture in school aged children typically developed and with handwriting disorders." European Psychiatry 65, S1 (June 2022): S751. http://dx.doi.org/10.1192/j.eurpsy.2022.1939.

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Introduction The knowledge aboutthe integration of letter motor programs during learning to write support the idea of an interdependence of visual and kinesthetic controls to direct the strokes. Objectives The objective of our study is to analyze the effect of the vision suppression both on the postural-gestural organization and on the spatial/temporal/kinematic parameters in a prescriptural task. Methods 35 school aged children with handwriting disorders (HD group) aged 6-11 years and 35 matched typical children were included in the study. They performed a prescriptural task of copying a cycloid line of loops, carried out under two conditions, with open eyes versus closed eyes. Postural-gestural measures were recorded with two video cameras allowing 2D reconstruction of the gesture. Spatial/temporal/kinematic measures were recorded with a digital pen. Results The HD group showed a significantly poorer postural control and an improvement in the spatial/temporal/kinematic parameters of the loops when they closed their eyes compared to eyes open. In typical group, the postural-gestural organization became significantly more mature but with no significant influence on the spatial/temporal/kinematic parameters of the loops. Conclusions HDs could be partly explained by a deficit in the processing of proprioceptive/kinesthetic feedback and a disruptive effect of the visual control on the quality of the prescriptural drawings. The ability to direct the strokes would remain dependent on sensory feedbacks, themselves insufficiently efficient, which would lead to difficulties in reaching a proactive control of handwriting. These results should be able to enhance clinical practices and to contribute to clinical decision making processes for handwriting disorders remediation. Disclosure No significant relationships.
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Bereskin, D., and I. A. Gorbunov. "Features of Bioelectric Activity of the Cerebral Cortex and Thinking Disorders in Children with Various Borderline Disorders of Residual Organic Genesis." Experimental Psychology (Russia) 14, no. 1 (2021): 151–71. http://dx.doi.org/10.17759/exppsy.2021140107.

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The article presents the results of a study of the features of cognitive function and bioelectric activity cerebral cortex in children with borderline mental disorders of residually organic genesis. 80 children participated with the following diagnoses: organic emotionally labile [asthenic] disorder [F 06.06]; inorganic enuresis [F 98.0], encopresis [F 98.1], stereotypical motor disorders [F 98.4], other specified emotional and behavioral disorders with onset usually occurring in childhood [F 98.8]. The features of bioelectric activity of the cerebral cortex, the ability to spatial analysis and synthesis, arithmetic counting, assimilation of logical and grammatical structures, the presence of viscosity, detail and diversity intellectual activity were studied in children. Data of electroencephalographic examinations were compared with the results of psychodiagnostic methods using the methods of mathematical statistics. Differences of bioelectric activity and features of thinking in children were investigated depending on features of boundary disorder. It is shown that on the background of asthenization more pronounced cognitive impairment is observed. Children with asthenic disorders [06.06] have the largest scatter of data than patients with enuresis [F98.0], encopresis [F 98.1], stereotypical movement disorders [F 98.4], disorders of behavior [F 98.8]. At the same time, on average, they have the most significant violations of thinking, what happens against the background of increasing spectral power of low-frequency activity of delta and theta rhythms in general, as well as of delta rhythm in the frontal part of the brain. Increase of low-frequency activity in the frontal lobes of both hemispheres leads to more pronounced disorders of thinking, than similar changes in the temporal, parietal, occipital regions of the right hemisphere and speech zones of the left hemisphere. In the first case, they are manifested in violations of spatial analysis and synthesis, viscosity, detail and diversity of thinking, as well as in difficulties in the semantic and symbolic activity, in the assimilation of logical and grammatical structures and arithmetic. In the second case — only in violations of spatial analysis and synthesis, viscosity, detail and diversity of thinking.
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Hegemann, Stefan, Sabine Fitzek, Clemens Fitzek, and Michael Fetter. "Cortical vestibular representation in the superior temporal gyrus." Journal of Vestibular Research 14, no. 1 (April 27, 2004): 33–35. http://dx.doi.org/10.3233/ves-2004-14103.

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We present the unique case of a patient with a circumscribed solitary cerebral metastasis of a malignant melanoma extending from the medial part of the superior temporal gyrus to the lower part of the 1st long insular gyrus causing gait and stance instability and an ipsiversive tilt of the subjective visual vertical. Oculomotor disorders could not be detected. We suggest that the superior temporal gyrus is likely to be involved in spatial orientation presumably using otolithic information.
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Dissertations / Theses on the topic "Spatial-temporal disorders"

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Stewart, Jillian. "Spatial and temporal effects on visual filtering in autism spectrum disorder." Thesis, McGill University, 2014. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=121544.

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The ability to filter irrelevant stimuli in order to attend to meaningful sources of information is crucial to all aspects of adaptive functioning, as real-life environments involve innumerable and consistently moving and changing stimuli. This study was designed to examine the ability of children with autism spectrum disorder (ASD) and their typically developing peers (TD) to visually filter potentially distracting task-irrelevant stimuli in order to better process and respond to task-relevant information. A modified version of the flanker paradigm (Eriksen & Eriksen, 1974) was used, in which participants responded to a 'target' stimulus presented at the centre of a computer screen with irrelevant 'flanker' stimuli presented to the left and right along the same horizontal plane. The flanker stimuli varied in shape (similar or dissimilar to target), distance from targets (1.16°, 3.46°, or 6.89° of visual angle), and in temporal onset relative to target onset (simultaneous, or 150ms, 300ms, or 450ms after target) so that the conditions that affect visual filtering performance could be identified. The speed and accuracy of participants' target identification were measured under each of these conditions. The participants included school-aged children with ASD (n= 13) and TD children (n= 13) matched on mental age (mean MA = 8.6 years). Both groups of children had faster RTs when flankers were similar to targets than when they were dissimilar. Children with ASD also showed improved performance when flankers and target were presented simultaneously, and weakened performance with increasing onset asynchrony. Unlike TD children, who had faster RTs when flankers were at a far distance from targets, participants with ASD were unaffected by distance manipulations. This is an indication of a deficit in children with ASD to adjust the focus of attention, a process that is essential to educational success among school-aged children.
Être capable de filtrer les stimuli non pertinents afin de se concentrer sur les sources d'information significatives est de première importance dans le fonctionnement adaptif, car l'environnement de chaque individuel est composé d'innombrables stimuli qui changent sans cesse. Cette étude cherche à mieux comprendre la capacité des enfants avec des troubles du spectre autistique (TSA) à filtrer des stimuli visuels distractifs pour accéder plus facilement aux sources d'informations pertinentes, comparé à des enfants qui démontrent un développement typique (DT). Une version modifiée de la tâche "flanker paradigm" (Eriksen & Eriksen, 1974) a été utilisée, dans laquelle les participants répondent à un stimulus (la "cible") présenté au centre de l'écran d'ordinateur, avec des stimuli qui flanquent (les stimuli "distractifs") la cible, de gauche et de droite, sur le même axe horizontal. Les stimuli distractifs varient en tant que forme (soit similaires ou dissimilaires à la cible), distance de la cible (angle visuel de 1.16°, 3.46°, ou 6.89°), et temps d'apparition relatif à la cible (simultanés, ou +150ms, + 300ms, ou +450 ms), pour identifier les conditions qui affectent la performance de filtration visuelle. La vitesse et la précision de l'identification de la cible ont été mesurées pour chacune de ces conditions. Les participants étaient des enfants d'âge scolaire avec TSA (n =13) et DT (n = 13), avec l'âge mental (AM) égalisé (moyenne AM = 8.6 ans). Les deux groupes d'enfants répondaient plus rapidement quand les distractifs ressemblaient à la cible que quand ils ne ressemblaient pas. Les enfants avec le TSA ont aussi démontré une performance améliorée quand les distractifs et la cible étaient présentés simultanément, et une performance diminuée avec des délais croissants entre l'apparition de la cible et les distractifs. Contrairement aux enfants DT, qui répondaient plus rapidement quand les distractifs étaient plus éloignés de la cible, les participants avec TSA n'étaient pas affectés par la manipulation de la distance. Ceci indique un déficit dans les enfants avec le TSA d'ajuster leur attention, une procédure qui est essentielle au succès scolaire parmi les enfants d'âge scolaire.
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Scheible, Colleen G. "THE USE OF SPATIAL, TEMPORAL, AND METAPHORICAL TERMS BY CHILDREN WITH AUTISM SPECTRUM DISORDER." Miami University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=miami1556746121099907.

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VARALTA, Valentina. "FUNCTIONAL AND NEURAL BASES OF SPATIAL-TEMPORAL DISORDERS OF VISUAL AWARENESS." Doctoral thesis, 2013. http://hdl.handle.net/11562/557550.

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L’estinzione visiva è un disturbo spazio-temporale di visual awareness. Pazienti con lesioni all’emisfero destro che presentano estinzione visiva spesso mostrano difficoltà nel rilevare lo stimolo controlesionale quando presentato contemporaneamente ad uno stimolo ipsilesionale (condizione di stimolazione bilaterale). In questi pazienti spesso inoltre lo stimolo di sinistra deve essere presentato con un vantaggio temporale per poter essere percepito come simultaneo a quello di destra. Nel presente lavoro, sono stati condotti tre esperimenti al fine di indagare le basi funzionali e neurali dei disturbi spazio-temporali di visual awareness. Attraverso il primo esperimento abbiamo indagato i correlati neurali di tali disturbi in pazienti con ictus in fase cronica con estinzione visiva. I deficit di visual awareness potrebbero in linea di principio dipendere da una disfunzione della corteccia parietale posteriore dovuta alla lesione della giunzione temporo-parietale, area tipicamente danneggiata nei pazienti con disturbi di visual awareness. Infatti la corteccia visiva ipsilesionale che risulta strutturalmente intatta potrebbe essere funzionalmente normale ma la sua attività viene modulata in maniera patologica a causa delle influenze top-down che derivano dalla corteccia parietale posteriore, e questo creerebbe asimmetria interemisferica. Tuttavia, non è ancora chiaro se l'effetto di una modulazione top-down disfunzionale influenzi esclusivamente le risposte del paziente o se induca cambiamenti neurali nelle aree visive. In questo esperimento, abbiamo cercato di indagare tale aspetto utilizzando la tomografia ad emissione di posizione (PET) a riposo in pazienti post-ictus. Nello specifico attraverso tale metodica abbiamo comparato il metabolismo corticale di un paziente che mostra estinzione visiva in fase cronica con quello di due pazienti che hanno recuperato il disturbo in fase acuta e che al momento dell’esame PET non evidenziavano deficit di visual awareness. Dai risultati si evidenzia che nel paziente con estinzione la corteccia visiva ipsilesionale, seppur strutturalmente intatta, risulta ipometabolica rispetto alla corteccia visiva controlesionale, mentre nessuna asimmetria interemisferica nelle aree visive è stata trovata nei pazienti senza estinzione. Questi dati suggeriscono che i cambiamenti neurali nelle aree occipitali strutturalmente intatte potrebbero essere cruciali per spiegare il disturbo di visual awareness per stimoli controlesionale in pazienti con estinzione in fase cronica. Nel secondo e nel terzo esperimento abbiamo studiato il possibile contributo dei meccanismi di cattura contingente dell’attenzione nell’elaborazione spazio-temporale delle informazioni visive, sia in pazienti con disturbi dell'attenzione (esperimento 2) sia in soggetti sani (esperimento 3). Dalla letteratura emerge che il deficit attentivo dei pazienti con lesioni parietali destre può essere determinato dalla difficoltà di disancorare l’attenzione da stimoli ipsilesionale per riorientarla verso stimoli controlesionali. È stato tuttavia dimostrato che il deficit di disancoraggio dipende della rilevanza che gli stimoli ipsilesionali assumono sulla base della richiesta del compito e/o delle aspettative del paziente. Anche studi su soggetti sani suggeriscono che l’aspettativa per una modalità sensoriale può accelerare la relativa percezione dello stimolo presentato in quella modalità piuttosto che in un’altra, riducendo il tempo necessario per la rilevazione dello stimolo stesso (ipotesi del “prior entry”). Il secondo esperimento si è concentrato sull’indagine delle basi funzionali dei disturbi spazio-temporali di visual awareness nei pazienti con estinzione visiva. Nello specifico abbiamo indagato se la richiesta del compito influenza l'elaborazione spazio-temporale delle informazioni visive in questi pazienti. Sono state valutate le prestazioni di un paziente con estinzione visiva in un compito di giudizio di ordine temporale. Il compito era eseguito in 2 diverse condizioni: in un caso s’istruiva il paziente ad eseguire il compito focalizzando la propria attenzione su un particolare stimolo (focused condition) mentre in un altro si chiedeva di eseguire il compito senza focalizzare l’attenzione su uno specifico stimolo (non-focused condition). Le prestazioni del paziente sono state confrontate con quelle di un paziente cerebroleso destro senza estinzione visiva e di quattro soggetti sani comparabili per età. Nella condizione non-focused il paziente con estinzione ha mostrato un bias spazio-temporale (PSS = -255), mentre si è evidenziata una riduzione importante di tale bias nella condizione focused (PSS = -44). Questi risultati indicano una chiara modulazione delle prestazioni del paziente sulla base del set attentivo utilizzato. Al contrario, nessuna modulazione è stata trovata sia nel paziente cerebroleso (condizione non-focused: PSS = -4, condizione focused: PSS = -2) che nei soggetti sani (condizione non-focused: PSS media = -16, condizione focused: media PSS = 3). Inoltre il paziente con estinzione ha mostrato una maggiore accuratezza nella discriminazione temporale di stimoli controlesionali, ma non di quelli ispilesionali, nella condizione focused (62,5%) rispetto alla condizione non-focused (46,7%). Lo scopo del terzo esperimento è stato quello di indagare le possibili influenze dei meccanismi di cattura contingente dell’attenzione sull’elaborazione spazio-temporale delle informazioni visive in soggetti sani. Diciotto soggetti sono stati testati attraverso un compito di giudizio di ordine temporale simile a quello utilizzato nell'esperimento 2. Nella condizione non-focused i soggetti non hanno mostrato alcun bias nel giudizio di ordine temporale (PSS = -3,6). Al contrario focalizzando l’attenzione su uno specifico stimolo (condizione focused) i soggetti mostravano un bias nel giudizio ordine temporale (PSS = -11) a favore di tale stimolo. Sulla base delle nostre conoscenze, questi sono i primi dati che dimostrano come la cattura dell’attenzione sia contingente al set attentivo anche in compiti di giudizio di ordine temporale.
Visual extinction is a spatial-temporal disorder of visual awareness. Right-hemisphere patients with visual extinction frequently miss the stimulus presented in their contralesional field on trials with bilateral presentation. They can also need the left stimulus to be presented with a temporal lead in order to be perceived as simultaneous to the right one. In the present work, three experiments were carried out in order to investigate functional and neural bases of spatial-temporal disorders of visual awareness. The first one focused on neural correlates of spatial-temporal disorders of visual awareness in patients with visual extinction at a chronic stage. An impairment of visual awareness is likely to depend upon unbalanced top-down modulation from dorsal fronto-parietal on occipital areas, typically intact in the ipsilesional hemisphere, biasing spatial-temporal processing of visual information towards the ipsilesional side. However, it is not clear yet whether the effect of a dysfunctional top-down modulation can only affect responses or, rather, induce neural changes in targeted visual areas. In this experiment, we addressed this issue by using position emission tomography (PET) at rest to measure possible differences between the cortical metabolism of one patient showing visual extinction at a chronic stage, and two patients who recovered from extinction, one at a chronic and another at a sub-acute stage. We found the structurally intact visual cortex of the extinction patient being hypometabolic in the right as compared to the left hemisphere, whereas no hemispheric asymmetry in the metabolism of visual cortex was found in the patients who recovered from extinction. Our data suggest that neural changes in structurally intact occipital areas might be crucial to explain the lack of visual awareness for contralesional stimuli in chronic extinction patients. In the second and third experiment we investigated the possible contribution of mechanisms of contingent attentional capture to spatial-temporal processing of visual information both in patients with attention disorders (experiment 2) and in healthy individuals (experiment 3). It was suggested that impairments of right parietal patients can be accounted for by a deficit in disengaging exogenous attention from ipsilesional stimuli and reorienting it towards contralesional events. It has been shown that the disengagement deficit depending on their behavioural relevance of ipsilesional stimuli (task demands and expectation of the patient). Also the results in the healthy subjects suggest that attending to a sensory modality can speed up the relative perception of stimulus presented in that rather than a different modality, reducing the time necessary for the stimulus to be perceived (“prior entry” hypothesis). The second experiment focused on functional basis of spatial-temporal disorders of visual awareness in patients with visual extinction, investigating whether task-set related factors can affect spatial-temporal processing of visual information in these patients. Specifically, we examined the performance of a visual extinction patient on a temporal order judgment (TOJ) task under conditions with different attentional set and compared his performance to that of one right-brain-damaged patient without visual extinction and four healthy subjects age matched. In the not focused condition the extinction patient shown spatial-temporal bias (PSS=-255), while he shown an important reduction of this bias under focused condition (PSS=-44). These findings indicate a clear modulation of patient’s performance with the attentional set, particularly for the PSS. On the contrary, no such a modulation was found both in the brain-damaged control patient (not focused condition: PSS=-4, focused condition: PSS=-2) and in healthy subjects (not focused condition: mean PSS=-16; focused condition: mean PSS=3). Furthermore the extinction patient showed higher accuracy of temporal discrimination for left-sided stimuli, but not for right-sides stimuli, in the focused (62,5%) as compared to the not focused (46,7%) condition. The aim of the third experiment was to investigate whether mechanisms of contingent attentional capture would also affect spatial-temporal processing of visual information in healthy subjects. Eighteen participants were tested on a similar TOJ paradigm as that used in experiment 2. In the not focused task-set condition subjects showed no bias in temporal order judgment (PSS=-3.6). On the contrary focusing subject’s attentional set onto one stimulus dimension yielded a clear-cut bias in temporal order judgment (PSS=-11). Present findings support evidence indicating that exogenous attention would affect sensitivity in a TOJ task and also extend this evidence, showing that in a TOJ task, as in other visual orienting tasks, capture of attention by external stimuli is contingent to the current attentional set.
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Fitterer, Jessica Laura. "The effects of alcohol access on the spatial and temporal distribution of crime." Thesis, 2017. http://hdl.handle.net/1828/7848.

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Increases in alcohol availability have caused crime rates to escalate across multiple regions around the world. As individuals consume alcohol they experience impaired judgment and a dose-response escalation in aggression that, for some, leads to criminal behaviour. By limiting alcohol availability it is possible to reduce crime; however, the literature remains mixed on the best practices for alcohol access restrictions. Variances in data quality and statistical methods have created an inconsistency in the reported effects of price, hour of sales, and alcohol outlet restrictions on crime. Most notably, the research findings are influenced by the different effects of alcohol establishments on crime. The objective of this PhD research was to develop novel quantitative approaches to establish the extent alcohol access (outlets) influences the frequency of crime (liquor, disorder, violent) at a fine level of spatial detail (x,y locations and block groups). Analyses were focused on British Columbia’s largest cities where policies are changing to allow greater alcohol access, but little is known about the crime-alcohol access relationship. Two reviews were conducted to summarize and contrast the effects of alcohol access restrictions (price, hours of sales, alcohol outlet density) on crime, and evaluate the state-of-the-art in statistical methods used to associate crime with alcohol availability. Results highlight key methodological limitations and fragmentation in alcohol policy effects on crime across multiple disciplines. Using a spatial data science approach, recommendations were made to increase spatial detail in modelling to limit the scale effects on crime-alcohol association. Providing guidelines for alcohol-associated crime reduction, kernel density space-time change detection methods were also applied to provide the first evaluation of active policing on alcohol-associated crime in the Granville St. entertainment district of Vancouver, British Columbia. Foot patrols were able to reduce the spatial density of crime, but hot spots of liquor and violent assaults remained within 60m proximity to bars (nightclubs). To estimate the association between alcohol establishment size, and type on disorder and violent crime reports in block groups across Victoria, British Columbia a Poisson Generalized Linear Model with spatial lag effects was applied. Estimates provided the factor increase (1.0009) expected in crime for every additional patron seat added to an establishment capacity, and indicated that establishments should be spaced greater than 300m a part to significantly reduce alcohol-associated crime. These results offer the first evaluation of seating capacity and establishment spacing on alcohol-associated crime for alcohol license decision making, and are pertinent at a time when alcohol policy reform is being prioritized by the British Columbia government. In summary, this dissertation contributes 1) cross-disciplinary policy and methodological reviews, 2) expands the application of spatial statistics to alcohol-attributable crime research, 3) advances knowledge on local scale of effects of different alcohol establishment types on crime, 4) and develops transferable models to estimate the effects of alcohol establishment seating capacity and proximity between establishments on the frequency of crime.
Graduate
2018-02-27
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Books on the topic "Spatial-temporal disorders"

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Roberts, Timothy P. L., and Luke Bloy. Neuroimaging in Pediatric Psychiatric Disorders. Edited by Dennis S. Charney, Eric J. Nestler, Pamela Sklar, and Joseph D. Buxbaum. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780190681425.003.0060.

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Noninvasive imaging and electrophysiological techniques have been developed to probe specific aspects of brain function and dysfunction, providing exquisite spatial maps of functional centers and temporal characteristics. The evolution of these techniques has advanced from single-modality methods identifying functional localization, specialization and segregation, through real-time measures of neuronal activity, toward multimodality integration of structural, functional, and spectro-temporal approaches. While these have an immediate impact in conditions where physical brain lesions are evident (e.g., brain tumor and stroke), making a commensurate contribution within neuropsychiatry is more complex. Nonetheless, by combining concepts of morphology, neurochemistry, neural signal propagation, and regional connectivity, there appears to be ample opportunity to contribute not only to the diagnosis of patients with mental illness but to the stratification and subtyping across behavioral phenotypes and, ultimately, to patient management. Here we present an overview of the most common noninvasive neuroimaging methodologies and their applications to pediatric neurodevelopmental disorders.
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Maquet, Pierre, and Julien Fanielle. Neuroimaging in normal sleep and sleep disorders. Edited by Sudhansu Chokroverty, Luigi Ferini-Strambi, and Christopher Kennard. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780199682003.003.0011.

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Functional neuroimaging techniques include methods that probe various aspects of brain function and help derive models of brain organization in health and disease. These techniques can be grouped in two categories. Some are mainly based on electromagnetic signals (electroencephalography, magnetoencephalography), recording brain activity using a large number of sensors with exquisite temporal resolution (usually of the order of a kilohertz) but allowing only indirect characterization of three-dimensional brain activity by resorting to mathematical models. The second type includes different techniques (PET scan, SPECT, MRI, optical imaging) that typically assess metabolic or hemodynamic parameters, with millimeter spatial resolution and usually from the entire brain volume. However, temporal resolution is usually low because it is primarily driven by metabolic processes that unfold in several seconds or minutes. This chapter focuses on this second type, covering the contribution of brain imaging to understanding NREM sleep and REM sleep and also sleep disorders.
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Wassermann, Eric M. Direct current brain polarization. Edited by Charles M. Epstein, Eric M. Wassermann, and Ulf Ziemann. Oxford University Press, 2012. http://dx.doi.org/10.1093/oxfordhb/9780198568926.013.0007.

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The transcranial application of weak direct current (DC) to the brain is an effective neuromodulation technique that has had more than a century of experimental and therapeutic use. Focal DC brain polarization is now undergoing renewed interest, because of the wide acceptance of TMS as a research tool and candidate treatment for brain disorders. The effects of static electrical fields on cortical neurons in vivo have been known since the advent of intracellular recording. These effects are highly selective for neurons oriented longitudinally in the plane of the electric field. DC can enhance cognitive processes occurring in the treated area. The earliest clinical application of DC polarization was in the field of mood disorders. However, due to lack of temporal and spatial resolution, this technique does not appear particularly useful for exploring neurophysiological mechanisms.
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Monteggia, Lisa M., and Wei Xu. Methods for In Vivo Gene Manipulation. Edited by Dennis S. Charney, Eric J. Nestler, Pamela Sklar, and Joseph D. Buxbaum. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780190681425.003.0004.

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Recent advances in mouse genetics have opened many new avenues of research in which to explore gene function in the brain, and contributions to the pathophysiology and treatment of psychiatric disorders. The use of the mouse to explore gene function has contributed a better understanding of the role of specific genes in the nervous system including their influence on neural circuits and complex behavior.This chapter explores current approaches to manipulate gene function in a mouse. Genetically modified mice allow for the investigation of a particular gene in vivo. The approaches discussed highlight recent advances to specifically overexpress or disrupt a specific gene of interest in the brain. We also highlight viral-mediated gene transfer approaches to allow for spatial and temporal control of gene function.
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Kiszka, Krzysztof. Ruchy osuwiskowe w świetle badań dendrogeomorfologicznych na podstawie analizy osuwiska Sawickiego w Beskidzie Niskim = Landsilde movements based on dendrogeomorphological research based on a analysis of the Sawicki Landslide in the Beskid Niski mts. Instytut Geografii i Przestrzennego Zagospodarowania im. Stanisława Leszczyckiego, Polska Akademia Nauk, 2021. http://dx.doi.org/10.7163/9788361590835.

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Research concerns the problem of landslide movement, which is one of the most important geomorphological processes in the Carpathians. The aim of the studies is to determine the temporal and spatial complexity of landslide activity and to demonstrate the suitability of using different species of conifers in the dendrogeomorphological method. The Sawicki landslide located in Beskid Niski Mts., which is one of the largest landslides in the Polish Flysch Carpathians, was selected for dendrogeomorphological analysis. The dendrogeomorphological method and geomorphological mapping were used in the research. 1078 samples from conifers (fir, spruce, larch and pine) growing on the Sawicki landslide and its immediate surroundings were taken using an increment borer in 2013- 2018. The cores were taken from the upslope and downslope side of the tree stump. The width of annual tree rings were measured for each extracted core sample. The landslide activity was assessed on the basis of the eccentricity, the eccentricity index and its yearly variation. Geological and topographic maps, published data on landslides activity in the research area, precipitation data from the Research Station in Szymbark (Institute of Geography and Spatial Organization Polish Academy of Science) for 1968-2017 and from the meteorological station in Krynica (Institute of Meteorology and Water Management) for 1881-2010 were also used for dendrogeomorphological research of Sawicki landslide. The research shows that the Sawicki landslide is characterized by varied temporal and spatial complexity of landslide activity. The dynamics of displacements within the research sites and research sub-sites, including various fragments of landslides, and movements of colluvial packages is spatially mosaic and chaotic in time. Mass movements covering almost the entire surface of the landslide occurred in the years 1913-1914 and 1974-1975, while in the years 1888, 1906-1907, 1916, 1918, 1929, 1965, 1973, 1980, 1983-1985, 1997 landslide activity was recorded only in its particular parts. The largest variation in the dynamics of landslide movements is characteristic for the period 1970-1985. It was also found that in the initial stage of formation of the landslide tongue, the colluviums movement is disordered. During further downhill movement, the direction of displacement is arranged. Periods of Sawicki landslide activity refers to extremely humid years (62%) and wet years (48%) and they are consistent with the years of landslides activity in Szymbark, listed in the current literature of the subject. The most predisposed conifer species to dendrogeomorphological analysis were spruce, larch and fir. Despite its limitations, the dendrogeomorphological method is a useful tool in landslide activity research.
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Book chapters on the topic "Spatial-temporal disorders"

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Skillicorn, David B., Olivier J. Walther, Quan Zheng, and Christian Leuprecht. "Spatial and temporal diffusion of political violence in North and West Africa." In African Border Disorders, 87–112. New York : Routledge, 2017. | Series: Routledge studies in African politics and international relations: Routledge, 2017. http://dx.doi.org/10.4324/9781315166483-5.

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Misbah, Chaouqi. "Order and Disorder both Spatial and Temporal near a Hopf Bifurcation." In Complex Dynamics and Morphogenesis, 319–38. Dordrecht: Springer Netherlands, 2016. http://dx.doi.org/10.1007/978-94-024-1020-4_12.

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Zhu, Yingying, Xiaofeng Zhu, Han Zhang, Wei Gao, Dinggang Shen, and Guorong Wu. "Reveal Consistent Spatial-Temporal Patterns from Dynamic Functional Connectivity for Autism Spectrum Disorder Identification." In Medical Image Computing and Computer-Assisted Intervention – MICCAI 2016, 106–14. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-46720-7_13.

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Chandran, Siddharthan, and Alastair Compston. "Demyelinating disorders of the central nervous system." In Oxford Textbook of Medicine, 4948–63. Oxford University Press, 2010. http://dx.doi.org/10.1093/med/9780199204854.003.0241002_update_001.

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Clinicians suspect demyelination when episodes reflecting damage to white matter tracts within the central nervous system occur in young adults. The paucity of specific biological markers of discrete demyelinating syndromes places an emphasis on clinical phenotype—temporal and spatial patterns—when classifying demyelinating disorders. The diagnosis of multiple sclerosis, the most common demyelinating disorder, becomes probable when these symptoms and signs recur, involving different parts of the brain and spinal cord. Other important demyelinating diseases include post-infectious neurological disorders (acute disseminated encephalomyelitis), demyelination resulting from metabolic derangements (central pontine myelinosis), and inherited leucodystrophies that may present in children or in adults. Accepting differences in mechanism, presentation, and treatment, two observations can usefully be made when classifying demyelinating disorders. These are the presence or absence of inflammation, and the extent of focal vs. diffuse demyelination. Multiple sclerosis is prototypic for the former, whereas dysmyelinating disorders, such as leucodystrophies are representative of the latter....
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Tiège, Xavier De, and Veikko Jousmäki. "Investigations of the Somatosensory System with Magnetoencephalography." In Fifty Years of Magnetoencephalography, 225–46. Oxford University Press, 2020. http://dx.doi.org/10.1093/oso/9780190935689.003.0016.

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This chapter reviews the historical contribution of magnetoencephalography (MEG) to the understanding of the functioning of the somatosensory system and how some achievements have been transferred to clinical research or routine to be integrated in clinical guidelines. Considering the vast literature and the existence of comprehensive MEG review papers on the topic, the chapter focuses on pioneering or specific studies in a historical framework. Thanks to its noninvasiveness and excellent temporal and good spatial resolutions, MEG has substantially contributed in the past 50 years to the characterization of the spatial, temporal, and spectral dynamics of somatosensory system activity. It has brought a tremendous amount of novel insights into the neural mechanisms at the basis of body perception. The methods developed for this purpose appeared useful in clinical routine and also in clinical research to investigate the pathophysiology of various brain disorders.
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Sivasubramaniyan, V., and K. Venkataramaniah. "Focal Increased Radiopharmaceutical Uptake Differentiation Using Quantitative Indices." In Radiopharmaceuticals [Working Title]. IntechOpen, 2021. http://dx.doi.org/10.5772/intechopen.99065.

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Focal increased radiopharmaceutical uptake in a lesion results in focal Hot Spots in the scans. This can occur in benign infective or inflammatory disorders and cancerous diseases as well. Comparison between malignant and benign lesions is important. The Hot spots can be classified into benign and malignant lesions by Spatial Scintimetry or Temporal Scintimetry. Spatial Scintimetry compares the uptake in the region of interest with the adjacent tissue or the unaffected contralateral site. The quantitative indices are lesion/non lesion ratio, lesion/background activity and lesion to Bone ratio etc. The Temporal Scintimetry relies on the changes in the counts or uptake in the Hotspot lesion with reference to the dual point time of acquisition. The Hotspot in the bone scan can be classified using the quantitative index of retention ratio by Dr. V. Siva and Israel. In PET studies the focal hot spots can be differentiated into benign and malignant lesion using the dual phase PETCT evaluation using the Rong’s Retention ratio and Dr. V. Siva’s modified RRI values.
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Zhou, Lang, Pengyu Chen, and Aleksandr Simonian. "Advanced Biosensing towards Real-Time Imaging of Protein Secretion from Single Cells." In Biosensor - Current and Novel Strategies for Biosensing [Working Title]. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.94248.

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Protein secretion of cells plays a vital role in intercellular communication. The abnormality and dysfunction of cellular protein secretion are associated with various physiological disorders, such as malignant proliferation of cells, aberrant immune function, and bone marrow failure. The heterogeneity of protein secretion exists not only between varying populations of cells, but also in the same phenotype of cells. Therefore, characterization of protein secretion from single cell contributes not only to the understanding of intercellular communication in immune effector, carcinogenesis and metastasis, but also to the development and improvement of diagnosis and therapy of relative diseases. In spite of abundant highly sensitive methods that have been developed for the detection of secreted proteins, majority of them fall short in providing sufficient spatial and temporal resolution for comprehensive profiling of protein secretion from single cells. The real-time imaging techniques allow rapid acquisition and manipulation of analyte information on a 2D plane, providing high spatiotemporal resolution. Here, we summarize recent advances in real-time imaging of secretory proteins from single cell, including label-free and labelling techniques, shedding light on the development of simple yet powerful methodology for real-time imaging of single-cell protein secretion.
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Plerou, Antonia, and Panayiotis Vlamos. "Evaluation of Mathematical Cognitive Functions with the Use of EEG Brain Imaging." In Advances in Multimedia and Interactive Technologies, 284–306. IGI Global, 2016. http://dx.doi.org/10.4018/978-1-4666-8659-5.ch014.

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During the last decades, the interest displayed in neurocognitive and brain science research is relatively high. In this chapter, the cognitive neuroscience field approach focuses in the aspect of the way that cognitive functions are produced by neural circuits in the brain. Within this frame, the effects of impairment to the brain and subsequent changes in the thought processes due to changes in neural circuitry resulting from the ensued damage are analyzed and evaluated. All cognitive functions result from the integration of many simple processing mechanisms, distributed throughout the brain. Brain cortex structures, linked with cognitive disorders, are located in several parts like the frontal, the parietal, the temporal, the occipital lobe and more are analyzed and specified. A critical topic of this chapter in the evaluation of brain operations is mapping regions that control cognitive and mathematical concepts functions. Dyscalculia, in this chapter, is described as a specific disorder of managing and conceiving mathematical concepts. Dyscalculia could be identified by difficulties in visual perception, in spatial number organization, in basic mathematical operations and in mathematical induction logic. Moreover, people who deal with dyscalculia present problems, in Euclidean and Non-Euclidean Geometry concepts perception, in Calculus aspects as well as in solving algorithmic problems where the design, the description and the application of algorithmic steps are required. In order to enhance cognitive brain functions perception, the use of EEG brain imaging is proposed measuring cerebral activity and event-related potentials. The procedure described in this chapter is about the comparison and contrasts EEG brain imaging patterns of healthy volunteers to EEG samples taken of adults considered being at risk of mathematics learning disabilities such as Dyscalculia and algorithmic thinking difficulties. EEG interpretation analysis is to follow where the deviation of a normal and an abnormal range of wave's frequency are defined. Several visualized EEG patterns in relevance with specific abnormalities are presented while several neurocognitive generated disorders could be identified with the use of EEG Brain-imaging technique. The electroencephalogram EEG brain imaging procedure, in order to evaluate problems associated with brain function, is to be further analyzed in this chapter as well. The EEG is the depiction of the electrical activity occurring at the surface of the brain. The recorded waveforms reflect the cortical electrical activity and they are generally classified according to their frequency (Delta, Theta, Beta, Alpha, Beta, and Gamma) amplitude, and shape. EEG Implementation with the use of 10/20 system of the standardized position of scalp electrodes placement for a classical EEG recording is described as well. The EEG implementation objective is to identify, classify and evaluate those frequencies and regions in the brain that best characterize brain activity associated with mathematical learning disabilities. Mapping the brain with non-invasive techniques based on trigger and sensing/evaluation experimental multimedia methods similar to those used in computer games and applications are expected to provide relevant results in order to enhance and confirm theoretical cognitive aspects. At that point, a cognitive and mathematical perception evaluation is to follow and specifically the assessment of the relation of difficulties in mathematics with particular parts of the human brain. EEG wave data visualization is contacted with the use of Acknowledge an interactive, intuitive program which provides data analysis instantly. At the end of this chapter EEG computational evaluation with the use of pattern recognition methods as well as the intuition of author's future work in relevance with the use of experimental multimedia technologies to enhance the dynamic recognition and evaluation of user cognitive responses during EEG implementation are noted.
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Conference papers on the topic "Spatial-temporal disorders"

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Tyler, Christopher W. "Why We Need to Pay Attention to Psychometric Function Slopes." In Vision Science and its Applications. Washington, D.C.: Optica Publishing Group, 1997. http://dx.doi.org/10.1364/vsia.1997.sud.2.

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One of the key tools of noninvasive visual assessment(\p)(p) is the measurement of visual thresholds in a variety of test targets, including letter acuity charts, perimetric visual fields, spatial and temporal sensitivity functions, color discrimination thresholds and so on through many variants. Implicit in the measurement of any threshold (of either the detection or discrimination type) is a psychometric function of percent correct versus stimulus strength. A neglected variable in the analysis of psychometric data is the steepness of the psychometric function, which is usually assumed to be fairly stable across conditions and observers and therefore to play little role in determining the measured sensitivity levels and their disturbances by eye disorders.
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Genack, Azriel Z. "Optical transmission in disordered media." In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1986. http://dx.doi.org/10.1364/oam.1986.fs1.

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Optical propagation is studied in samples of random close-packed polystyrene and titania spheres with indices of refraction n = 1.59 and n ≃ 2.8, respectively. Both spatial and temporal aspects of propagation are probed by measuring the transmission of light as a function of sample thickness as well as fluctuations in the transmitted light intensity as a function of laser frequency. Fluctuations in intensity with amplitude as large as the average intensity of light are observed within a single coherence area of a speckle pattern as the laser frequency is scanned. This makes clear the essential role of interference in transport and makes possible the measurement of the width of the distribution in the transit time of light through the sample.
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Rocha, Andreia, Bruna Bellaver, Luiza Machado, Carolina Soares, Pâmela C. L. Ferreira, Samuel Greggio Gianina T. Venturin, Jaderson C. da Costa, Diogo O. Souza, and Eduardo R. Zimmer. "TEMPORAL CHANGES IN ASTROCYTES ON A TRANSGENIC RAT MODEL OF AD." In XIII Meeting of Researchers on Alzheimer's Disease and Related Disorders. Zeppelini Editorial e Comunicação, 2021. http://dx.doi.org/10.5327/1980-5764.rpda023.

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Background: Recent evidences have pointed to astrocytes as important players in the Alzheimer’s Disease (AD) pathogenesis. Objective: With this in mind, we aim to longitudinally investigate astrocyte changes in a new important AD transgenic model, the TgF344-AD rat, the first animal model harboring human APP/PS1 mutations which presents age-dependent amyloid and tau pathology. Methods: TgF344-AD rats and wild type littermates were evaluated in three time points: 3, 6 and 9 months of age. Rats underwent a [18F]FDG-microPET, a spatial-memory, an astrocytes CSF biomarkers (ELISA multiplex) and a glutamate uptake (ex-vivo slices) analysis. Examination of further time-points are being conducted at the moment. Results: At 9 months of age, TgF344-AD animals presented an increase in the cortical [18F]FDG uptake and a decline in their alternance performance in the Y-maze task. In the CSF analysis, GFAP was elevated at both 6 months and 9 months, while S100B presented a decrease at 6mo. Additionally, the cortical glutamate uptake was increased at 9 months. Conclusion: This study is the first to longitudinally investigate the in vivo brain glucose metabolism in the TgF344-AD rat model. Our results suggest that this model presents an early increase on glucose metabolism which may be related to astrocytes activation and the increase of glutamate uptake by these cells. Furthermore, we also identified a spatial memory impairment at the same age.
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Wei, Xile, Dong Lin, Lihui Cai, Meili Lu, Jiang Wang, and Bin Deng. "Characterization of Spatial Temporal Dynamic of Brain Network in Disorder of Consciousness via Community Analysis." In 2020 39th Chinese Control Conference (CCC). IEEE, 2020. http://dx.doi.org/10.23919/ccc50068.2020.9189127.

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Cronin-Golomb, Alice, S. Corkin, and J. H. Growdon. "Alzheimer’s disease: a disorder of the precortical visual system?" In OSA Annual Meeting. Washington, D.C.: Optica Publishing Group, 1986. http://dx.doi.org/10.1364/oam.1986.tut1.

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Alzheimer’s disease (AD) is characterized by maximal degeneration of the parietal and temporal lobes with relative sparing of primary visual areas. As may be expected from this pattern of degeneration, AD patients as a group are widely impaired on tests of higher-order visuospatial function, whereas only a minority show deficiencies in color vision, Vernier acuity, and stereoacuity. This pattern of functional sparing of basic visual processes does not hold, however, for contrast sensitivity function, which is commonly impaired at all spatial frequencies in patients with AD, relative to age-matched controls.1 In cats, ablation of the striate cortex results in only modest changes in contrast sensitivity function; furthermore, blocking the ON channel in the monkey retina affects contrast sensitivity but not color discrimination, acuity, motion detection or stereopsis. Thus contrast sensitivity, unlike the other basic visual functions we have measured in AD, may involve precortical brain areas. In light of a recent report of optic nerve degeneration and retinal changes in AD,2 these observations raise the intriguing possibility that, as far as basic visual processes are concerned, AD is a precortical, not a cortical disease.
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Iwai, T., and J. C. Dainty. "Pathlength Distribution Function of Dynamic Multiple Light Backscattering in Dense Disordered Media." In Photon Correlation and Scattering. Washington, D.C.: Optica Publishing Group, 1992. http://dx.doi.org/10.1364/pcs.1992.tub3.

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Investigations on the propagation of light in random media have been of current interest The static backscattered light exhibits the photon localization (intensity enhancement) at the exact backward direction1). The dynamic backscattered light shows the minimum correlation time at the exact backward direction and double peaks in its both sides2). Both features are closely related with each other by considering the trajectory of the photon transport in the media. In this study, we shall examine to derive the pathlength distribution function from the autocorrelation function using Levenberg-Marquardt method3) and reveal the relation between the spatial and temporal features of the backscattered light from dense random media by using the pathlength distribution function.
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Reports on the topic "Spatial-temporal disorders"

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Grumstrup, Erik. Final Technical Report: Photoconversion in Disordered Semiconductors: Spatial, Spectral, and Temporal Insights through Nonlinear Microscopy. Office of Scientific and Technical Information (OSTI), November 2022. http://dx.doi.org/10.2172/1897590.

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Howes, F. A., and D. L. Stein. Studies of spatial and temporal disorder in macroscopic systems. Final report, April 1, 1993--May 31, 1998. Office of Scientific and Technical Information (OSTI), June 1998. http://dx.doi.org/10.2172/621902.

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