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1.
Acta Psychol (Amst) ; 202: 102958, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31864215

RESUMO

A novel illusion entitled "the letter height superiority effect" has been demonstrated. This shows that letters are perceived as being taller than pseudoletters, while in reality their objective sizes are identical. An explanation of this illusion has been proposed in the framework of the Interactive Activation Model. Indeed, we postulated that the more a feature is activated, the taller a stimulus is perceived as being. The objective of the current study was to test this postulate by manipulating feature activation through signal-to-noise ratio. We presented gray stimuli (low signal-to-noise ratio) or black ones (high signal-to-noise ratio). In a first experiment, participants judged the size of pairs of either letters or pseudoletters presented as black or gray. In a second experiment we presented pairs consisting of a letter and a pseudoletter, of identical or different colors. In a third experiment, we presented pairs of letters or pseudoletters of identical or different colors by block to test the possible effect of previous exposure on perceptual judgments. The results showed that for identical objective size, participants perceive black stimuli to be taller than gray ones and that the effects of the nature of the stimuli and their color are cumulative. The results also indicated that the effects were not due to previous exposure to color or sizes. These results confirm the Interactive Activation Model as a credible explanation for the letter height superiority effect.


Assuntos
Percepção de Cores/fisiologia , Ilusões/fisiologia , Ilusões/psicologia , Reconhecimento Visual de Modelos/fisiologia , Estimulação Luminosa/métodos , Adolescente , Adulto , Feminino , Humanos , Julgamento/fisiologia , Masculino , Tempo de Reação/fisiologia , Adulto Jovem
2.
Behav Ther ; 50(6): 1173-1184, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31735251

RESUMO

BACKGROUND: Anxiety sensitivity cognitive concerns (ASCC), or fear of cognitive dyscontrol sensations, confers risk for anxiety and mood psychopathology. Recent work demonstrated that novel perceptual challenges generated by a head mounted display can elicit fear among those with elevated ASCC. This suggests that interoceptive exposure to perceptual challenges may offer a means to mitigate ASCC. This study was designed to evaluate whether repeated exposure to novel perceptual challenges can reduce ASCC, and if these effects are stronger among those experiencing greater negative emotionality as a proxy for individuals likely to present for treatment. METHODS: Participants with elevated ASCC (N = 57) were randomized to one of three experimental conditions utilizing a head-mounted display. In the rotations condition (n = 20), participants viewed themselves spinning in a circle. In the opposite directions condition (n = 20), participants turned their head while the camera moved in the opposite direction creating dissonance in their visual field. In the control condition (n = 17), participants completed a series of simple arithmetic problems. RESULTS: Participants in the rotation condition, relative to control, reported significant reductions in ASCC from pre- to post-exposure and these effects were strongest for those with elevated negative affect. The main effect of the opposite directions exposure on post-treatment ASCC was non-significant, but follow-up analyses revealed that reductions in ASCC were observed among those with elevated negative affectivity. DISCUSSION: Perceptual illusion challenges appear to have utility for reducing ASCC through repeated exposure. There was evidence for the perceptual illusion exercises, particularly the rotations condition, specifically reducing ASCC, making this challenge the first we are aware of that specifically targets ASCC-related concerns. LIMITATIONS: As a proof-of-concept study, the present sample was not recruited for clinically-significant psychopathology, and only a brief follow-up was utilized. Future research should utilize a longer follow-up and test if these exposures mitigate ASCC-relevant psychopathology among clinical samples.


Assuntos
Ansiedade/psicologia , Ilusões/psicologia , Adulto , Afeto , Transtornos de Ansiedade/terapia , Medo/psicologia , Feminino , Humanos , Masculino , Adulto Jovem
3.
Psychol Aging ; 34(7): 978-990, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31621358

RESUMO

Although there is some evidence suggesting that audiovisual integration is inefficient in older adults, and that such inefficiency is associated with age-related functions such as mild cognitive impairment, falls, and balance maintenance, these associations have yet to be demonstrated in a population-representative study of ageing. Based on a sample of 3,955 adults aged over 50 years, we investigated the role of age, cognitive status, and sex on susceptibility to the sound-induced flash illusion (SIFI) as a measure of audiovisual temporal integration, while controlling for a range of covariates. We developed a hierarchical Bayesian, ordinal-regression model to determine which variables predicted audiovisual integration. Higher susceptibility to the SIFI was predicted by older age, female sex (at larger temporal asynchronies), and a lower score on the Montreal Cognitive Assessment (MoCA). Our results confirm, in a population-representative sample, that enhanced audiovisual integration is associated with ageing and extend the association between multisensory integration and mild cognitive impairment to global cognitive status. Importantly, the findings also highlight the role of the sex of the participant as a previously overlooked factor in studying multisensory perception in ageing. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Envelhecimento/psicologia , Percepção Auditiva/fisiologia , Cognição/fisiologia , Ilusões/psicologia , Sexo , Percepção Visual/fisiologia , Idoso , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
4.
Int J Occup Med Environ Health ; 32(5): 653-662, 2019 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-31511703

RESUMO

OBJECTIVES: The study analyzed the effectiveness of military pilots' behavior under the influence of false horizon illusion - a false perception of the real horizon. It was assumed that visual illusion tends to cause spatial disorientation (SD). The question was asked which orientation of the sloping cloud (right/left) would have a bigger impact on SD. The effectiveness of the flight profile performance under the influence of visual illusion was analyzed in the context of the field dependence (FD), field independence (FI) or field intermediate dependence (FINT) of perception, the effectiveness of attention and operational memory. MATERIAL AND METHODS: The study covered 66 pilots. A flight simulator was used as a measure of effectiveness in performing the flight profile in spatial disorientation conditions. The effectiveness of attention and working memory was diagnosed using 4 computer tasks. RESULTS: It was revealed that the right sloping cloud (compared to the left sloping cloud) had a greater impact on military pilots' behavior. The cognitive style distinguishes the accuracy of the flight profile performance from the inclined cloud pointing to the right. The comparisons showed significant differences between the FI and FD pilot groups. All the pilots demonstrated the right-sided asymmetry of the flight rate. While performing tasks on the simulator, the FI pilots were characterized by a more stable rate than the FINT pilots. CONCLUSIONS: A general conclusion is that the "correct falling cloud" had a greater impact on pilots' behavior. The presented results confirm the hypothesis that susceptibility to visual illusions is significantly increased in the pilots characterized by field dependence while the pilots with the FINT style of perception are characterized by a greater variability of the flight rate. Int J Occup Med Environ Health. 2019;32(5):653-62.


Assuntos
Cognição , Ilusões/psicologia , Pilotos/psicologia , Adulto , Medicina Aeroespacial , Simulação por Computador , Humanos , Memória de Curto Prazo , Militares/psicologia , Orientação Espacial , Campos Visuais
5.
Acta Psychol (Amst) ; 199: 102921, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31445425

RESUMO

The effects of moving task-irrelevant objects on time-to-contact (TTC) judgments are examined in six experiments. In particular, we investigated the effects of the symbolic meaning of speed on TTC by presenting images of objects recalling the symbolic meaning of high speed (motorbike, rocket, formula one, rabbit, cheetah and flying Superman) and low speed (bicycle, hot-air balloon, tank, turtle, elephant and static Superman). In all experiments, participants judged the TTC of these moving objects with a black line, indicating the end of the occlusion. Experiment 7 was conducted to disambiguate whether the effects on TTC, found in the previous experiments, were either a by-product of a speed illusion or they were rather elicited by the implicit timing task. In a two-interval forced choice task, participants were instructed to judge if "high-speed objects" moved actually faster than "slow-speed objects". The results revealed no consistent speed illusion. Taken together the results showed shorter TTC estimated with stimuli recalling the meaning of high compared to low speed, but only with the long occlusion duration (3.14 s). At shorter occlusion durations, the pattern was reversed (participant tend to have shorter TTC with stimuli recalling the meaning of low speed). We suggest that the symbolic meaning of speed works mainly at low speed and long TTC, because the semantic elaboration of the stimulus needs a deeper cognitive elaboration. On the other hand, at higher speeds, a small erroneous perceptual judgment affects the TTC, perhaps due to a speed expectancy violation of the expected "slow object".


Assuntos
Ilusões/fisiologia , Julgamento/fisiologia , Percepção de Movimento/fisiologia , Estimulação Luminosa/métodos , Percepção do Tempo/fisiologia , Adulto , Animais , Feminino , Humanos , Ilusões/psicologia , Masculino , Rememoração Mental/fisiologia , Coelhos , Fatores de Tempo , Adulto Jovem
7.
Acta Psychol (Amst) ; 198: 102870, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31301573

RESUMO

The standard visual search task is integral to the study of selective attention and in search tasks target present slopes are the primary index of attentional demand. However, there are times when similarities in slopes may obscure important differences between conditions. To demonstrate this point, we used the case of line-ending illusory contours, building on a study by Li, Cave, and Wolfe (2008) where orientation-based search for figures defined by line-ending illusory contours was compared to that for the corresponding real-contour controls. Consistent with Li et al. (2008), we found search to be efficient for both illusory contour figures and the corresponding real-contour controls, with no significant differences between them. However, major differences between illusory contours and the real-contour controls emerged in selective enumeration, a task where participants enumerated targets in a display of distractors, with the number of targets and distractors manipulated. When looking at the distractor slopes, the increase in RT to enumerate a single target as a function of the number of distractors (a direct analogue to target present trials, with identical displays), we found distractor costs for illusory contour figures to be over 100 ms/distractor higher than for the corresponding real-contour controls. Furthermore, the discrepancies in RT slope between 1-3 and 6-8 targets associated with subitizing were only seen in the real-contour controls. These results show that similarities in RT slopes in search may mask important differences between conditions that emerge in other tasks.


Assuntos
Percepção de Forma/fisiologia , Ilusões/psicologia , Reconhecimento Visual de Modelos/fisiologia , Desempenho Psicomotor/fisiologia , Adolescente , Atenção/fisiologia , Feminino , Previsões , Humanos , Ilusões/fisiologia , Masculino , Orientação/fisiologia , Estimulação Luminosa/métodos , Distribuição Aleatória , Adulto Jovem
8.
Exp Brain Res ; 237(8): 2111-2121, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31190083

RESUMO

Transcranial direct current stimulation (tDCS) has been widely used for modulating sensory, motor and cognitive functions, but there are only few attempts to induce and change illusory perception. Visual illusions have been the most traditional and effective way to investigate visual processing through the comparison between physical reality and subjective reports. Here we used tDCS to modulate two different visual illusions, namely the Brentano illusion and the glare effect, with the aim of uncovering the influence of top-down mechanisms on bottom-up visual perception in two experiments. In Experiment 1, to a first group of subjects, real and sham cathodal tDCS (2 mA, 10 min) were applied over the left and right posterior parietal cortices (PPC). In Experiment 2, real and sham cathodal tDCS were applied to the left and right occipital cortices (OC) to a second group of participants. Results showed that tDCS was effective in modulating only the Brentano illusion, but not the glare effect. tDCS increased the Brentano illusion but specifically for the stimulated cortical area (right PPC), illusion direction (leftward), visual hemispace (left), and illusion length (160 mm). These findings suggest the existence of an inhibitory modulation of top-down mechanisms on bottom-up visual processing specifically for the Brentano illusion, but not for the glare effect. The lack of effect of occipital tDCS should consider the possible role of ocular compensation or of the unstimulated hemisphere, which deserves further investigations.


Assuntos
Ofuscação , Ilusões/fisiologia , Estimulação Luminosa/métodos , Estimulação Transcraniana por Corrente Contínua/métodos , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Ilusões/psicologia , Masculino , Adulto Jovem
9.
Cyberpsychol Behav Soc Netw ; 22(7): 494-499, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31210540

RESUMO

Increasing evidence points to the role of interoception in body perception and in constructing the bodily self. Body ownership illusion (BOI) in virtual reality (VR) is a widely used paradigm to study body perception. However, existing research has focused mainly on exteroceptive sensory modalities, and studies on interoception and BOI remain scarce. The postulated mechanism of BOI is related to the multisensory integration of information and visuo-tactile or visuo-kinesthetic sensory conflict resolution. In this within-subjects experimental study, we introduced systematic visuo-interoceptive (visuo-respiratory) conflicts and tested if participants would resolve them by adjusting their respiration rate (RR). Participants observed a virtual breathing avatar body from the first-person perspective while their own RR was recorded. The VR system was connected to a respiration monitor. The avatar was first breathing for 60 seconds in accordance with the participant's RR; then, it was either slowing down or speeding up, each condition lasting for 180 seconds. The dependent variable was a change in participants' RR, expressed as a linear regression slope coefficient. Forty participants were included in each experimental condition, in a counterbalanced order. There was a change in RR in the predicted direction in both conditions. Participants' RR decreased on average by 0.48 breaths/minute and increased by 0.64 breaths/minute, leading to a change of 1.45 and 1.93 breaths/minute, respectively, over the entire timespan of the experiment. The difference between conditions was statistically significant (V = 192, p < 0.01). Because a change in RR of even 1 breath/minute is considered clinically significant, the results of this study-apart from demonstrating visuo-respiratory conflict resolution-may have an applied significance.


Assuntos
Imagem Corporal/psicologia , Ilusões/psicologia , Respiração , Taxa Respiratória , Realidade Virtual , Adulto , Feminino , Humanos , Masculino
10.
Atten Percept Psychophys ; 81(8): 2902-2916, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31165452

RESUMO

The perception of quantities has been suggested to rely on shared, magnitude-based representational systems that preserve metric properties. As such, different quantifiable dimensions that can characterize any given stimulus (e.g., size, speed, or numerosity) have been shown to modulate the perceived duration of these stimuli-a finding that has been attributed to cross-modal interaction among the quantity representations. However, these results are typically based on the isolated effects of a single stimulus dimension, leaving their potential combined effects uncharted. In the present study we aimed to investigate the joint effects of numerical magnitude and physical size on perceived time. In four complementary experiments, participants categorized six durations as "short" or "long," which were presented through combinations of Hindu-Arabic numerals in three font sizes, as well as with simple shapes (rectangles) and unfamiliar symbols (Klingon letters), the sizes of which corresponded to the font sizes of the Hindu-Arabic numerals. Our results showed temporal underestimation for the smallest numeral in the set (3), with no effects of font size on perceived duration. The perceived durations were longest for the physically smallest geometric stimuli (i.e., a rectangle), and the font size of symbol-like stimuli (i.e., Klingon letters) was not found to have an effect on perceived time. Finally, presenting only one numeral (6) instead of the rectangle once again eliminated the relationship between physical size and perceived time, suggesting an overshadowing of physical-size-based influences on temporal choice behavior, presumably by perceived symbolism. Our results point at the complex nature of the interaction between different magnitude representations.


Assuntos
Ilusões/fisiologia , Ilusões/psicologia , Conceitos Matemáticos , Estimulação Luminosa/métodos , Simbolismo , Percepção do Tempo/fisiologia , Adolescente , Adulto , Feminino , Humanos , Masculino , Adulto Jovem
11.
Exp Brain Res ; 237(8): 2061-2073, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31172241

RESUMO

Frequency-dependent brightness enhancement, a perceptual illusion in which a flickering light can appear twice as bright as a constant light, has historically been reported to produce maximum effects at a flicker rate within the alpha (8-12 Hz) band (Bartley in J Exp Psychol 23(3):313-319, 1938). Our recent examinations of this phenomenon using brightness discrimination between two flickering stimuli, however, have instead revealed the brightest percepts from theta-band (4-7 Hz) flicker (Bertrand et al. in Sci Rep 8(1):6152, 2018). Two primary questions arise from these seemingly contradictory findings: first, could task differences between these studies have caused recruitment of discrete oscillatory processes? Second, could the reported theta-band flicker enhancement be the result of an aliased alpha rhythm, sequentially sampling two stimulus locations, resulting in an ~ 5 Hz half-alpha rhythm? Here, we investigated these questions with two experiments: one replicating Bartley's (1938) adjustment paradigm, and one containing both Bartley's adjustment task and Bertrand's (2018) discrimination task, but presenting stimuli only sequentially (rather than concurrently). Examination of a range of frequencies (2-12 Hz) revealed the greatest brightness enhancement arising from flicker in the delta- and theta-band across all conditions, regardless of the spatial or temporal configuration of the stimuli. We speculate that these slower rhythms play an integral role in complex visual operations (e.g., a discrimination decision) where the entrainment of the endogenous neural rhythm to matched exogenous rhythmic stimulation promotes more efficient processing of visual information and thus produces perceptual biases as seen in frequency-dependent brightness enhancement.


Assuntos
Ritmo alfa/fisiologia , Ritmo Delta/fisiologia , Aprendizagem por Discriminação/fisiologia , Ilusões/fisiologia , Estimulação Luminosa/métodos , Ritmo Teta/fisiologia , Adolescente , Feminino , Humanos , Ilusões/psicologia , Luminescência , Masculino , Distribuição Aleatória , Percepção Visual , Adulto Jovem
12.
Rev. Asoc. Esp. Neuropsiquiatr ; 39(135): 33-49, ene.-jun. 2019. tab
Artigo em Espanhol | IBECS | ID: ibc-186380

RESUMO

Tradicionalmente ha existido una incongruencia entre la definición de conciencia y la caracterización de su patología, que se restringe a aquellos cuadros que afectan la vida consciente en su conjunto, ya sea por un descenso del nivel o por una desorganización de sus contenidos. Los avances en neurociencia cognitiva han demostrado que existen otras perturbaciones de la conciencia que no implican su afectación total. Con el fin de presentar una clasificación integral de estos trastornos, partiremos de las teorías de Edelman y Damasio, quienes diferencian una forma elemental de conciencia (conciencia primaria, para el primero, o central, para el segundo) de una forma compleja (conciencia de orden superior o ampliada, respectivamente). Las enfermedades que afectan a la conciencia primaria producen trastornos globales, pues afectan a la conciencia en su conjunto. Los trastornos de la conciencia superior producen perturbaciones parciales, que involucran mayormente a la autoconciencia, aunque también incluyen las distorsiones y engaños perceptivos


Traditionally, there has been an incongruity between the definition of consciousness and the characterization of its pathology, which is restricted to those disorders that affect consciousness as a whole, either by a decrease in its level or by a disorganization of its contents. Developments in cognitive neuroscience have shown that there are other disturbances of consciousness that do not imply its total involvement. In order to present a comprehensive classification of these disorders, we will build our classification on the theories of Edelman and Damasio, who differentiate an elementary form of consciousness (primary or core consciousness, respectively) from a complex one (higher order or extended consciousness, respectively). Diseases that affect primary consciousness cause global disorders, because they affect consciousness as a whole. Disorders of higher-order consciousness cause partial disturbances, which mostly involve self-consciousness. Perceptual distortions and deceptions are also included here


Assuntos
Humanos , Transtornos da Consciência/classificação , Inconsciência/psicologia , Consciência , Estado de Consciência/classificação , Metacognição , Delírio/psicologia , Amnésia/psicologia , Teoria da Mente , Ilusões/psicologia , Alucinações/psicologia
13.
Exp Brain Res ; 237(7): 1773-1779, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31037326

RESUMO

Whether visible or not, knowing the location of our hands is fundamental to how we perceive ourselves and interact with our environment. The present study investigated perceived hand location in the absence of vision in 30 participants. Their right index finger was placed 10, 20 or 30 cm away on either side of the body midline, with and without their left index finger placed 10 cm to the left of the right index. On average, at each position, participants perceived their right hand closer to the body midline than it actually was. This underestimation increased linearly with increased distance of the hand from body midline [slope 0.77 (0.74 to 0.81), mean (95% CI)]. Participants made smaller errors in perceived hand location when the right hand was in the contralateral workspace [mean difference 2.13 cm (1.57 to 2.69)]. Presence of the left hand on the support surface had little or no effect on perceived location of the right hand [mean difference [Formula: see text] cm ([Formula: see text] to 0.02)]. Overall, participants made systematic perceptual errors immediately after hand placement. The magnitude of these errors grew linearly as the hand got further away from the body midline. Because of their magnitude, these errors may contribute to errors in motor planning when visual feedback is not available. Also, these errors are important for studies in which perceived hand location is assessed after some time, for example, when studying illusions of body ownership and proprioceptive drift.


Assuntos
Mãos/fisiologia , Ilusões/fisiologia , Ilusões/psicologia , Propriocepção/fisiologia , Percepção do Tato/fisiologia , Percepção Visual/fisiologia , Adulto , Feminino , Humanos , Masculino
14.
Psychon Bull Rev ; 26(4): 1195-1212, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31044361

RESUMO

The current study comprises the first systematic meta-analysis of weight illusions. We obtained descriptive data from studies in which subjective heaviness estimates were made for pairs or groups of objects that had the same mass and different volumes (size-weight illusion; SWI) or different apparent material properties (material-weight illusion; MWI). Using these data, we calculated mean effect sizes to represent illusion strength. Other study details, including stimulus mass, volume, density, and degree of visual and somatosensory access to the stimuli were also recorded to quantify the contribution of these variables to effect sizes for the SWI. The results indicate that the SWI has a larger mean effect size than the MWI and that the former is consistent in strength when information about stimulus size is gained through somatosensory channels, regardless of visual access. The SWI is weaker when only the visual system provides size information. Effect sizes for the SWI were larger when there was a greater difference in volume across the stimuli. There was also a positive correlation between SWI strength and the difference in physical density across the different experimental stimuli, even after controlling for volume differences. Together, we argue that these findings provide support for theories of weight illusions that are based on conceptual expectancies as well as those that are based on bottom-up processing of physical density. We further propose that these processes, which have been considered dichotomously in the past, may not be mutually exclusive from each other and could both contribute to our perception of weight when we handle objects in everyday life.


Assuntos
Ilusões/psicologia , Percepção de Tamanho , Percepção de Peso , Humanos
15.
Exp Brain Res ; 237(7): 1821-1832, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31079236

RESUMO

The rubber hand illusion (RHI) is a perceptual phenomenon in which participants experience ownership over a fake model hand through synchronous visuotactile stimulation. Several studies have shown that the illusion occurs only when both hands are in close proximity to each other. In the present study, we systematically examined the role of relative position (lateral, distal) and distance (13-75 cm) of the model hand (with respect to participants' real hand) on illusion experience across both lateral and distal positions. Furthermore, we also compared different facets of the subjective illusion experience; the experience of the model hand being part of one's body (i.e., ownership) and the perceptual fusion of vision and touch (i.e., referral of touch). In two experiments we observed indications for a stronger illusion experiences in distal compared to lateral positions of identical distances, indicating that the illusory effects may vary as a function of the relative position of the hand. Our results also showed that manipulations of distance differently modulated both facets of the illusion. While ownership was restricted to near distances, referral of touch sensations remained stable at farther distances. These results are interpreted in relation to variations in sensory weighting across different planes.


Assuntos
Percepção de Distância/fisiologia , Mãos/fisiologia , Ilusões/fisiologia , Estimulação Luminosa/métodos , Propriocepção/fisiologia , Percepção do Tato/fisiologia , Feminino , Humanos , Ilusões/psicologia , Masculino , Distribuição Aleatória , Percepção Espacial/fisiologia , Adulto Jovem
16.
Psychiatry Res ; 276: 262-268, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31125903

RESUMO

Suicide remains a public health concern with suicide rates showing a consistent increase over the last 20 years. Recent studies have found a relationship between anxiety sensitivity (i.e., the fear of anxiety related symptoms) and suicidality. Specifically, a relationship has been found between anxiety sensitivity cognitive concerns (ASCC) and suicidality. The knowledge around this relationship, however, has relied mostly on self-report measures. This study seeks to expand on the current literature by exploring the association between ASCC and suicidality, through the use of head-mounted display perceptual illusion challenges (e.g., using tactile sensations and mannequins to create illusions that the participant has switched bodies). A head-mounted display was used to elicit symptoms (e.g., depersonalization, derealization) related to ASCC in a sample of undergraduate students (N = 54). Suicidality and depression were measured by the Inventory of Depression and Anxiety Symptoms-2 (IDAS-II), anxiety sensitivity cognitive concerns by the Anxiety Sensitivity Index-3 (ASI-3), and distress by the Subjective Units of Distress Scale (SUDS). Findings indicated that suicidality was associated with self-reported ASCC as well as the fear generated from the challenges. Furthermore, our results found that challenge-induced fear predicted suicidality scores above and beyond the traditional self-report measures of ASCC. The small sample size and low suicide risk of the current sample limits generalizations to more severe populations.


Assuntos
Ansiedade/psicologia , Medo/psicologia , Ilusões/psicologia , Suicídio/psicologia , Adolescente , Adulto , Despersonalização/psicologia , Depressão/psicologia , Feminino , Humanos , Masculino , Fatores de Risco , Estudantes/psicologia , Adulto Jovem
17.
Atten Percept Psychophys ; 81(5): 1500-1511, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30850939

RESUMO

This study investigates the bi-directionality of synaestesic experience by means of a flanked bisection paradigm in TT, a number-colour synaesthete. Previous studies have shown that bisection is shifted towards the larger digit flanker (e.g., Ranzini & Girelli, 2012). TT and controls performed line bisections with lines flanked by black digits (experiment 1), by TT's photism colours (experiment 2), and by congruently (experiment 3), or incongruently coloured digits (experiment 4). While the results of the control group mainly replicated previous findings, only the colour-digit congruence elicited in TT the larger-digit bias. TT's absence of effects in the other conditions was not due to reduced sensitivity to luminance effects (experiment 5), or to mathematical expertise (experiment 6). We suggest that grapheme-colour synaesthesia might be characterised by a rigid access to semantic representation when the inducer is task-irrelevant.


Assuntos
Cognição , Percepção de Cores/fisiologia , Ilusões/psicologia , Transtornos da Percepção/psicologia , Semântica , Adulto , Cor , Feminino , Humanos , Masculino , Adulto Jovem
18.
PLoS One ; 14(2): e0211914, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30785901

RESUMO

INTRODUCTION: Positive psychotic experiences are associated with increased rate of white noise speech illusions in patients and their relatives. However, findings have been conflicting to what degree speech illusions are associated with subclinical expression of psychosis in the general population. The aim of this study was to investigate the link between speech illusions and positive psychotic experiences in a general population sample. In addition, the hypothesis that speech illusions are on the pathway from known risk factors for psychosis (childhood adversity and recent life events) to subthreshold expression of psychosis, was examined. METHODS: In a follow-up design (baseline and 6 months) the association between the number of white noise speech illusions and self-reported psychotic experiences, assessed with the Community Assessment of Psychic Experiences (CAPE), was investigated in a general population sample (n = 112). In addition, associations between speech illusions and childhood adversity and life events, using the Childhood Experiences of Care and Abuse questionnaire and the Social Readjustment Rating Scale, were investigated. RESULTS: No association was found between the CAPE positive scale and the number of white noise speech illusions. The CAPE positive scale was significantly associated with childhood adversity between 12 and 16 years (B = 0.980 p = 0.001) and life events (B = 0.488 p = 0.044). The number of speech illusions showed no association with either life events or childhood adversity. CONCLUSION: In the nonclinical population, the pathway from risk factors to expression of subclinical psychotic experiences does not involve white noise speech illusions as an intermediate outcome.


Assuntos
Ilusões/psicologia , Ruído/efeitos adversos , Transtornos Psicóticos , Inquéritos e Questionários , Adulto , Criança , Maus-Tratos Infantis/psicologia , Pré-Escolar , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Transtornos Psicóticos/fisiopatologia , Transtornos Psicóticos/psicologia , Fatores de Risco
19.
J Exp Psychol Gen ; 148(10): 1675-1687, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30730194

RESUMO

The human perceptual system is responsive to numerical information within visual and auditory scenes. For example, when shown 2 displays of dots, observers can instantly, albeit approximately, identify the set that is more numerous. Theories in perceptual and cognitive psychology have focused on 2 mechanisms for how vision accomplishes such a feat: Under the domain-specific encoding theory, number is represented as a primary visual feature of perception, much like motion or color, while under the domain-general theory, the visual system represents number indirectly, through a complex combination of features such as the size of the dots, their total cluster, and so forth. Evidence for the latter theory often comes from "congruency effects:" the finding that participants frequently select the side where the dots on the screen are denser, larger, or brighter, rather than the side that is actually more numerous. However, such effects could also stem from response conflicts between otherwise independent dimensions. Here, we test these 2 competing accounts by embedding numerical displays within visual illusions that create large conflicts between number and other non-numeric dimensions-including contour length, convex hull, and density-and contrast participants' performance on a number discrimination task (i.e., "Which side has more dots?") against a number estimation task (i.e., "How many dots are there?"), which should eliminate response conflicts. Across 3 experiments, we find that while contour length illusions only affect number perception in discrimination tasks, the influences of convex hull and density on number perception persist in both discrimination and estimation tasks, supporting a more domain-general account of number encoding. (PsycINFO Database Record (c) 2019 APA, all rights reserved).


Assuntos
Atenção/fisiologia , Cognição/fisiologia , Ilusões/psicologia , Percepção Visual/fisiologia , Feminino , Percepção de Forma/fisiologia , Humanos , Masculino
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