Visual Capture of a Tactile Sensation is Influenced by Repeated, Structured Exposure of a Visual Stimulus in Virtual Reality

Phantom limb pain is commonly known as a neurological condition, where an amputee will continue to feel a limb that is no longer present in a painful fashion. Virtual mirror therapy (VMT) has been suggested as a method for alleviating phantom limb pain. The inclusion of tactile sensation in VMT has shown to be beneficial; however, delivering a tactile sensation to a phantom limb, without the use of invasive procedures, can be difficult. The current approach for transferring a tactile sensation to a phantom limb is called visual capture. The ability to establish visual capture has been demonstrated in VMT applications. However, there is little research into whether an established visual capture effect can be relocated to a more distal location for phantom limb pain management. This paper investigates whether a passive vibrotactile sensation can be moved to a distal location from its veridical location using a series of distally located lights presented in either a random or a structured fashion. Eight non-amputee participants were tasked with localising a static tactile sensation on a virtual arm. These vibrotactile sensations were presented simultaneously with a visual light stimulus, either co-located or located distally at three different locations. Findings show that a tactile sensation without a visual stimulus was difficult for participants to localise; however, when a visual stimulus was added, they were better able to locate the veridical tactile position. The structured group exhibited a larger range of tactile relocation responses than the random group. However, this result was unreliable, with the majority of the responses situated at the vibrotactile actuator. There was a significant difference between the random and structured group’s ability to retain a visual capture at the veridical vibrotactile location when the lights were located distally. The random group did not express a visual capture response when the lights were presented distally while the structured group did, suggesting the structured group developed a more robust association between the visual stimulus and the vibrotactile stimulus. Findings may be of use where increasing tactile acuity without significant alteration of a veridical location is a desired therapeutic outcome.

The McGurk Effect in Qatari Arabic: Influences of Lexicality and Consonant Position

The McGurk effect is a psycholinguistic phenomenon where an illusion is made by dubbing an auditory element of one sound on a visual element of another sound, which leads to hearing a third sound. The phenomenon demonstrates how the perception of speech does not depend on audio inputs only. Rather, it shows how seeing the shape of the mouth while producing a certain sound can influence what we hear. Thus, it proves the interaction of both vision and auditory parameters in understanding language. In addition, what is known as “lexicality – the property of a word being real or not” influences speech perception. People, unconsciously, tend to alter nonwords to real words. For example, if one said “shtrength” instead of “strength”, a listener would alter and understand it as “strength”. For the purpose of the research, these two phenomena were combined. In this study, we test how effective is the McGurk effect on the Qatari Arabic dialect, which has not been investigated before. The data used were 24 minimal pairs of real and fake words with the substitution of the phonemes: /b/ and /g/ at three different positions: first, middle, final. Videos were made by dubbing audio recordings of the sound /b/ into video recordings of the sound /g/ in order to test if this creates an illusion of the sound /d/. We ran the experiment on 25 native Qatari female students, they had to sit on a computer with headphones on, watch and hear clearly what the person on the video is saying, and then they had to preform two tasks: first, lexical decision task: decide if the word is real or fake. Second, sound discrimination task: choose what sound did they hear. In general, the participants captured audio (which means they heard /b/) were only 16% of target trials, while visual capture occurred (which means they heard /g/) 45%, and the McGurk fusion (which means they heard /d/) happened on 39%. Interestingly, perceiving McGurk fusion was gradually less common at later consonants positions. A significant effect of lexicality was also found, as fusion was more likely to occur if the results of the fusion was a real word.

Outrageously Real

This chapter dismantles the common distinction between modernist aestheticism and documentary reference by studying André Gide’s factual writings. In his recollections of his experiences as a juror (Souvenirs de la cour d’assises, 1914) and his reports on court cases in the Nouvelle Revue Française series “Ne jugez pas” (“Judge Not,” 1930), Gide’s ostensibly impersonal organization of testimonial evidence produces a complex polyphonic construction that claims to let documents speak for themselves, while in fact articulating them within a larger discourse. In Voyage au Congo (1927) and Le Retour du Tchad (1928) Gide’s politically engaged writing on French Equatorial Africa enters into dialogue with the largely apolitical documentary film-making practices of his travelling companion Marc Allégret. Commenting on Allégret’s cinematic practices, Gide both reflects on the limitations of documentary and attempts to rival film’s visual capture of living gesture.

Evaluation of biodiversity metrics through environmental DNA metabarcoding compared with visual and capture surveys in river fish community

Information on alpha (local), beta (between habitats), and gamma (regional) diversity is fundamental to understanding biodiversity as well as the function and stability of community dynamics. The methods like environmental DNA (eDNA) metabarcoding are currently considered useful to investigate biodiversity.We compared the performance of eDNA metabarcoding with visual and capture surveys in estimating alpha/gamma diversity and the variation of the community assemblages of river fish communities, particularly considering community nestedness and turnover.In five rivers across west Japan, with comparing to visual/capture surveys, eDNA metabarcoding detected more species in the study sites, consequently the overall number of species in the region (i.e., gamma diversity) was higher. In particular, the species found by visual/capture surveys were encompassed by those by eDNA metabarcoding.With analyzing the community assemblages between the rivers, we showed the different results between the both methods. While, in the same river, the nestedness and species turnover changing from upstream to downstream did not significantly differ between the both methods. Our results suggest that eDNA metabarcoding may be suitable method, especially for understanding regional community patterns, for fish monitoring in rivers.