A series of 5 experiments investigated whether false memory in associated word lists present with serial position effects (SPE) and how any such effects behave in response to manipulations of true recall SPE. Recall for a series of events is typified by SPE such that items nearer the beginning, primacy effect, and end, recency effect, of a series are remembered better than middle items. Recall is also typified by the intrusion of falsely remembered information. Word-lists segmented into trimesters of either semantically (e.g., hot, snow, warm.../ bed, rest, awake.../ looking, lens, shatter...) or phonologically (e.g., code, called, fold.../ sweep, sleet, steep.../ class, grass, glad...) associated words produced false recall (e.g., cold, sleep, glass), allowing for the simultaneous investigation of SPE for true and false recall. Typical SPE for true recall were observed for each of the five Experiments. For immediate free recall, semantic false recall declined from early to late study trimesters whereas phonological false recall displayed a false primacy and recency effect similar to true recall SPE. Phonological false recall was significantly reduced when a 15 second distractor task was implemented during the retention interval. Dividing attention during study using a concurrent handwriting task reduced true recall whereas semantic false recall increased at primacy and phonological false recall increased at recency. This suggests distinct processes underlying the two forms of false recall. Dividing attention using an articulatory suppression task produced less true recall and less false recall than using concurrent handwriting. This research indicates that false recall SPE exist and that the semantic and phonological forms of false recall SPE are distinct. Current theories of false memory and of true recall SPE are considered.

A series of 5 experiments investigated whether false memory in associated word lists present with serial position effects (SPE) and how any such effects behave in response to manipulations of true recall SPE. Recall for a series of events is typified by SPE such that items nearer the beginning, primacy effect, and end, recency effect, of a series are remembered better than middle items. Recall is also typified by the intrusion of falsely remembered information. Word-lists segmented into trimesters of either semantically (e.g., hot, snow, warm.../ bed, rest, awake.../ looking, lens, shatter...) or phonologically (e.g., code, called, fold.../ sweep, sleet, steep.../ class, grass, glad...) associated words produced false recall (e.g., cold, sleep, glass), allowing for the simultaneous investigation of SPE for true and false recall. Typical SPE for true recall were observed for each of the five Experiments. For immediate free recall, semantic false recall declined from early to late study trimesters whereas phonological false recall displayed a false primacy and recency effect similar to true recall SPE. Phonological false recall was significantly reduced when a 15 second distractor task was implemented during the retention interval. Dividing attention during study using a concurrent handwriting task reduced true recall whereas semantic false recall increased at primacy and phonological false recall increased at recency. This suggests distinct processes underlying the two forms of false recall. Dividing attention using an articulatory suppression task produced less true recall and less false recall than using concurrent handwriting. This research indicates that false recall SPE exist and that the semantic and phonological forms of false recall SPE are distinct. Current theories of false memory and of true recall SPE are considered.

Les silhouettes ambiguës, comme celle du lapin/canard (Jastrow, 1899), ont été étudiées selon plusieurs approches. Toutefois, les figures prises en exemples dans la large majorité des études sont généralement les mêmes. Cette redondance des images ambiguës utilisées pousse à croire qu'elles sont peut-être assez rares. Certaines observations anecdotiques suggèrent cependant qu’elles seraient au contraire relativement fréquentes. C'est ce que cherche à déterminer cette expérience. Nous avons utilisé des modèles tridimensionnels d'animaux projetés de façon aléatoire afin d'en extraire les silhouettes dont la complexité périmétrique a ensuite été modifiée par lissage. Treize sujets ont dû indiquer ce qu'ils percevaient dans l'image. Nous démontrons qu’une silhouette est classée en moyenne dans 1.9079 catégories de base. Nous avons également démontré qu’une diminution de la complexité périmétrique rend d’abord une silhouette plus ambiguë pour éventuellement atteindre un sommet (équivalent à environ six fois la complexité périmétrique d’un disque) à la suite duquel l’ambiguïté chute. / Ambiguous silhouettes such as the duck/rabbit (Jastrow, 1899) have been studied by several approaches. However, the figures taken as examples in the vast majority of studies are generally the same. This redundancy of the ambiguous images used in litterature implies they may be quite rare. On the other hand, anecdotal evidence suggests that they might be relatively frequent. This is what this experiment is trying to establish. We used three-dimensional models of animals from a random point of view to extract silhouettes whose perimetric complexity was subsequently modified by smoothing. Thirteen subjects were asked to indicate what they saw in the image. We show that silhouettes are classified on average with 1.9079 based categories. We also established that a decrease in the perimetric complexity initially makes a more ambiguous figure but that this effect eventually reaches a peak (at a perimetric complexity of approximately 6 times that of a disk) after which ambiguity drops.

Orientador: Dr. Marcelo Salvador Caetano / Dissertação (mestrado) - Universidade Federal do ABC, Programa de Pós-Graduação em Neurociência e Cognição, 2017. / A percepção de movimento pode alterar a percepção do tempo. Existem diferentes categorias de estímulos de movimento, entre eles: o movimento biológico (representação humana do movimento) e o movimento não biológico (qualquer outro tipo de representação do movimento não humano). Estudos de neuroimagem sugerem que algumas áreas corticais apresentam respostas mais evidentes para estímulos de movimento biológico (Sulco Temporal Superior ¿ STS) enquanto outras preferem o movimento não biológico (Giro Temporal Médio ¿ MTG, do inglês). Dado esses achados, o presente estudo se propôs primeiramente a investigar se categorias distintas de movimento (biológico e não biológico) poderiam modular a percepção de tempo de forma diferente. Além disso, o estudo também se propôs a examinar o padrão das respostas corticais hemodinâmicas das áreas STS e MTG durante a exposição aos estímulos de movimentos biológicos e não biológicos entre diferentes velocidades aparentes. O principal achado deste estudo refere-se à descrição de diferenças na distorção temporal entre estímulos com representação de movimento biológico e não biológico, em velocidades em que o movimento é julgado mais natural e plausível. Os resultados fisiológicos também sugerem uma diferença na atividade cortical hemodinâmica frente a estímulos com diferentes intensidades de movimento, além de mostrar correlações entre a percepção temporal e respostas fisiológicas. / The perception of motion can distort time perception. There are several categories of motion stimuli such as biological motion (human representation of motion) and non-biological motion (any other type of representation of non-human things). Neuroimaging studies suggest that some cortical areas in the brain are more responsive to stimuli of biological motion (Superior Temporal Sulcus), while others are more responsive to non-biological motion stimuli (Middle Temporal Gyrus). The present study has investigated if different categories of stimuli (biological and non-biological) can distort time perception in different manners. Furthermore, this study also investigated the patterns of hemodynamic responses in the STS and MTG areas while participants watched stimuli presented at different speeds. The main result was the difference in the temporal distortion caused by stimuli representing biological and non-biological motion in speeds in which the movement was judged to be natural and plausible. Physiological results suggest differences in hemodynamic responses during observation and performance in the time-reproduction task, and show correlations between temporal perception and cortical hemodynamic responses.

L'un des principaux objectifs des neurosciences est de comprendre comment les fonctions cognitives sont codées par la dynamique des grands réseaux neuronaux. L'étude de la perception sensorielle a principalement été axée sur l'enregistrement de l'activité neuronale induites par des stimulations sensorielles. Une approche alternative réside dans l'utilisation des illusions sensorielles. Ainsi, la perception sensorielle peut avoir lieu en l'absence de stimulation physique externe. Nous avons utilisé une approche multidisciplinaire combinant l'imagerie calcique à deux photons, le comportement moteur et l'optogénétique. Nous avons pu montrerque la larve de poisson zèbre est capable de percevoir " l'effet après mouvement " (EAM). En utilisant l'optogenetique (halorhodopsine) nous avons été capables d'inhiber les mouvementes oculaires pendant la présentation du stimulus conditionné (SC). Nous avons montré que les mouvements des yeux lors du SC ne sont pas impératifs pour l'induction de l'EAM, ce qui suggère que l'EAM n'est probablement pas d'origine musculaire. En utilisant la microscopie à deux photons nous avons montré une habituation de neurones tectales au cours de l'EAM. Cette habituation se dégrade selon une échelle de temps qui correspond au comportement oculo-moteur, lors de l'EAM. En revanche, les cellules ganglionnaires de la rétine ne sont pas habitués. Ceci indique que le toit optique, mais pas la rétine, joue un rôle prépondérant dans l'induction du EAM. Cette approche multidisciplinaire permet de comprendre de façon plus approfondie les mécanismes neuronaux sous-jacents au EAM, et de spéculer sur le corrélat neuronal de la perception du mouvement. / One of the main goals in neuroscience is to understand how cognitive functions are encoded by the dynamics of large neuronal networks. The main stream to study sensory perception has mainly focused on sensory stimulation and neuronal recordings of the induced neural responses. An alternative approach is the use of sensory illusions, in which sensory perception take place in the absence of physical external stimulation. For this purpose, we have used a multidisciplinary approach combining the zebrafish larva as the experimental model, two-photon calcium imaging, motor behavior and optogenetics. We showed that the zebrafish larva is capable of perceiving motion after-effect (MAE). Using optogenetics (halorhodopsin) to prevent eye movements during the presentation of the conditioning stimulus (CS), we showed that pursuit eye movements during CS are not imperative for the induction of MAE, suggesting that neither muscular fatigue nor eye-muscle proprioception feedback play a role in the generation of MAE. Furthermore, we used two-photon microscopy in combination with transgenic fish expressing GcaMP3 . We first observed that during MAE, neurons in the optic tectum (the largest and highest visual brain center of the larva) were strongly habituated. This habituation later decayed with a temporal scale that matched that of the optomotor MAE-like behavior. In contrast, no significant habituation was observed in the retina, Thus, we suggested that the optic tectum but not the retina plays a role in generation of MAE. Our approach contributed to a more comprehensive view of the neuronal mechanisms underlying MAE, and shed light on the neuronal correlate of motion perception

No description available.

This investigation is concerned with the role played by the illusions of security, Bolshevism, and American innocence in the making of the Versailles Treaty of 1919. The main sources used in this thesis were the U.S. State Department publications The World War and The Paris Peace Conference and Paul Mantoux's Proceedings of the Council of Four. The drafting of the Versailles Treaty is approached chronologically with special emphasis accorded the problems emanating from the questions of Russia and the Rhine. The study concludes that the peacemakers were manipulated by the illusions of security, Bolshevism, and American innocence.

No / BACKGROUND: Tripping is a common factor in falls and a typical safety strategy to avoid tripping on steps or stairs is to increase foot clearance over the step edge. In the present study we asked whether the perceived height of a step could be increased using a visual illusion and whether this would lead to the adoption of a safer stepping strategy, in terms of greater foot clearance over the step edge. The study also addressed the controversial question of whether motor actions are dissociated from visual perception. METHODOLOGY/PRINCIPAL FINDINGS: 21 young, healthy subjects perceived the step to be higher in a configuration of the horizontal-vertical illusion compared to a reverse configuration (p = 0.01). During a simple stepping task, maximum toe elevation changed by an amount corresponding to the size of the visual illusion (p<0.001). Linear regression analyses showed highly significant associations between perceived step height and maximum toe elevation for all conditions. CONCLUSIONS/SIGNIFICANCE: The perceived height of a step can be manipulated using a simple visual illusion, leading to the adoption of a safer stepping strategy in terms of greater foot clearance over a step edge. In addition, the strong link found between perception of a visual illusion and visuomotor action provides additional support to the view that the original, controversial proposal by Goodale and Milner (1992) of two separate and distinct visual streams for perception and visuomotor action should be re-evaluated.

Syftet med föreliggande studie var att ta fram ett svenskt material för att undersöka mottagligheten för semantiska illusioner vid bearbetning av auditivt språkligt meddelande hos vuxna individer utan kommunikationsstörning. Utöver detta syftade även studien till att undersöka om mottaglighet för den semantiska illusionseffekten är relaterad till lexikal åtkomst och arbetsminneskapacitet. I studiens initiala skede utformades det nya testmaterialet Auditivt test av mottaglighet för semantiska illusioner (ATSI). ATSI består av tre deltest, varje deltest innefattar 40 påståenden med en jämn fördelning av sanna påståenden, falska påståenden och illusoriska påståenden. Deltagarna i studien bestod av 30 vuxna individer utan kommunikationsstörning. Deltagarnas uppgift var att avgöra om påståendena i ATSI var sanna eller falska. Utöver ATSI utförde även deltagarna test gällande lexikal åtkomst och arbetsminneskapacitet. Effekten av semantiska illusioner analyserades genom t-test och visade att illusionseffekten var statistiskt signifikant. Resultaten från ATSI korrelerades med deltagarnas prestation gällande lexikal åtkomst och arbetsminneskapacitet. Hur lurade deltagarna blev av den semantiska illusionseffekten korrelerade med lexikal åtkomst. I föreliggande studie kunde inget samband observeras mellan hur lurade deltagarna blev och arbetsminneskapacitet. I diskussionen förs i föreliggande studie resonemang kring varierande metodologiska aspekter likväl som resultatens implikationer för den språkliga bearbetningsprocessen. Slutsatsen i föreliggande studie är att den semantiska illusionen är ett stabilt fenomen som har effekt vid bearbetning av språkligt meddelande auditivt. / The aim of this study was to construct a Swedish test material in order to examine the susceptibility for semantic illusions in adults without any communication disorders when processing verbal input of language. Furthermore the study aimed to investigate if the susceptibility for semantic illusions relates to the individual’s lexical access speed and working memory capacity. In order to accomplish the aim of the study, a new auditory test material called Auditivt Test av mottaglighet för Semantiska Illusioner (ATSI) was created. ATSI consists of three separate test sections, each containing 40 statements with an even distribution of true statements, false statements and statements containing the semantic illusion. The participants had to decide whether each statement was true or false. The participants in this study consisted of 30 adult individuals without communication disorders. Furthermore the participants performed test regarding lexical access speed and working memory capacity. The effects of semantic illusions were analyzed trough t-tests and found to be statistically significant. Correlation analysis were made between result from ATSI and lexical access speed as well as between results from ATSI and working memory capacity. How tricked the participants were by the semantic illusions was related to lexical access, but not working memory capacity. Methodological aspects are discussed in this study as well as the result’s implication for language processing. The conclusion is that semantic illusions is a stabile phenomenon, and it occurs when processing spoken sentences.

Psychological aspects of evidence evaluation: Abstract The diploma thesis focuses on the topic of judging and decision-making within the process of evidence evaluation. Its main goal is to identify and describe cognitive illusions which can have a negative impact on the process of evidence evaluation. The mutual position of psychology and law in also considered within introductory chapters. The decision making of the judges is initially described by theoretical models. Three cognitive illusions that are essential for evidence evaluation are described in the following chapter. It is anchoring heuristic, hindsight bias and confirmation bias. Eventually risks, which these cognitive illusions represent for evidence evaluation, are described and forms of countermeasures are discussed. One chapter of the thesis is devoted to the description of ego depletion, which could pose another limit for the process of evidence evaluation. Ego depletion describes decline of self-control in cases which demand conscious effort. The judges are probably in a risk of ego depletion. This phenomenon can lead to higher vulnerability towards cognitive illusions and stronger tendency to maintain status quo. Possible countermeasures are described and discussed on one hand against anchoring, hindsight and confirmation bias and on the...