Search results for "Illusions"
showing 10 items of 50 documents
Méprises
2013
Optical illusions in scanning electron micrographs: the case of the eggshell of Acrosternum (Chinavia) marginatum (Hemiptera: Pentatomidae)
2003
Scanning electron microscopy revealed that-as is common in this family of the Hemiptera-the eggs of the green stink bug Acrosternum (Chinavia) marginatum are roughly barrel-shaped and possess at their apical pole a row of slender extensions, the aero-micropylar processes. The outer surface of the eggshell carries hexagonally arranged pits. The analysis of cross-fractured eggshells showed that the pits have slender basal extensions with transverse diaphragms. When scanning electron micrographs of the egg surface of A. marginatum are viewed upside down, the perception flips and the pits appear as elevations to all observers addressed. Thus, we are dealing with an optical illusion, which is kn…
100 Years of Benham's Top in Colour Science
1995
For 100 years Benham's top has been a popular device demonstrating pattern-induced flicker colours (PIFCs). Results of early and recent investigations on PIFCs are reported and show that the phenomenon originates in phase-sensitive lateral interactions of modulated neural activity in the retina followed by additional spatial interactions in the visual cortex behind the locus of binocular fusion. Colour matches with normal colour stimuli indicate that S/(M + L) opponent neurons are involved. Dichromats do not find matching stimuli for all PIFCs. PIFCs may become useful in medical diagnosis. The phenomenon is interpreted as a side effect of a neural mechanism providing colour constancy under…
Op art et roman virtuel : correspondances entre Escher et Perec
2012
Op art et roman virtuel : correspondances entre Escher et Perec Les structures mathématiques, la notion de réalité comme « humaine illusion », le défi à l’infini et la structure énigmatique qui donne aux œuvres eschériennes la même structure que celle d’un roman policier permettent d’établir des convergences significatives entre le graveur hollandais et Georges Perec. Dans certaines œuvres de Perec, en effet, il est possible de remarquer des références explicites au graveur bien qu’elles constituent la traduction visuelle de l’angoisse du « retour du semblable », du « retour involontaire au même point ». Mais Perec ne se limite pas seulement à citer Escher, puisque certaines de ses œuvres c…
O069. Menstrual cycle affects cortical excitability differently in females with migraine and in healthy controls: a new perspective by cross modal so…
2015
The sound-induced flash illusions (SIFI) represent a valid tool to explore multimodal perception and are critically dependent on visual and acoustic cortical excitability [1, 2]. In a previous study [3], we observed a significant reduction of illusions in migraine patients with respect to healthy controls, probably due to a condition of visual cortex hyperexcitability. Aim of the present study was to evaluate SIFI perceptions in healthy women and patients with menstrual migraine and to describe the effects of cyclical change of steroid hormones and cortical responsiveness.
Somatosensory Illusions Elicited by Sham Electromagnetic Field Exposure: Experimental Evidence for a Predictive Processing Account of Somatic Symptom…
2020
OBJECTIVE According to the predictive processing theory of somatic symptom generation, body sensations are determined by somatosensory input and central nervous predictions about this input. We examined how expectations shape predictions and consequently bodily perceptions in a task eliciting illusory sensations as laboratory analogue of medically unexplained symptoms. METHODS Using the framework of signal detection theory, the influence of sham Wi-Fi on response bias (c) and somatosensory sensitivity (d') for tactile stimuli was examined using the somatic signal detection task (SSDT). A healthy student sample (n = 83) completed the SSDT twice (sham Wi-Fi on/off) in a randomized order after…
Design Anamorphosis in Math Class
2015
Many visual effects are based on mathematical, geometrical procedures. Creating visual illusions through playful activities hold exciting pedagogical opportunities for raising students’ interest towards mathematics and the technical aspects of visual arts. The Experience Workshop Math-Art Movement has a number of thematic workshops — developed through interdisciplinary collaborations between mathematics teachers, artists and scholars — that are connected to perspective illusions and visual paradoxes. In this paper we introduce classroom activities focusing on mathematical connections in anamorphosis, drawing inspiration from István Orosz’s anamorphic art. peerReviewed
Why are dreams interesting for philosophers? The example of minimal phenomenal selfhood, plus an agenda for future research1
2013
This metatheoretical paper develops a list of new research targets by exploring particularly promising interdisciplinary contact points between empirical dream research and philosophy of mind. The central example is the MPS-problem. It is constituted by the epistemic goal of conceptually isolating and empirically grounding the phenomenal property of “minimal phenomenal selfhood,” which refers to the simplest form of self-consciousness. In order to precisely describe MPS, one must focus on those conditions that are not only causally enabling, but strictly necessary to bring it into existence. This contribution argues that research on bodiless dreams, asomatic out-of-body experiences, and ful…
Why are dreams interesting for philosophers? The example of minimal phenomenal selfhood, plus an agenda for future research.
2013
This metatheoretical paper develops a list of new research targets by exploring particularly promising interdisciplinary contact points between empirical dream research and philosophy of mind. The central example is the MPS-problem. It is constituted by the epistemic goal of conceptually isolating and empirically grounding the phenomenal property of “minimal phenomenal selfhood,” which refers to the simplest form of self-consciousness. In order to precisely describe MPS, one must focus on those conditions that are not only causally enabling, but strictly necessary to bring it into existence. This contribution argues that research on bodiless dreams, asomatic out-of-body experiences, and ful…