1,721,097 research outputs found
Mazzurega, M., Occelli, V., Garberi, P., Esposito, G., & Zampini, M. (2014). Body representation and interpersonal socio affective factors: The enfacement illusion modulated by autistic-like traits. International Multisensory Research Forum, Amsterdam, The Netherlands, June, 11-14.
No full textChanges in spatial position of hands modify tactile extinction but not disownership of contralesional hand in two right brain-damaged patients
No full textSomatic misperceptions and misrepresentations, like supernumerary phantom limb and denial of ownership of a given body part, have typically been reported following damage to the right side of the brain. These symptoms typically occur with personal or extrapersonal neglect and extinction of left-sided stimuli, suggesting that all these different symptoms may be linked to the same neural substrate. In the present research, we tested two right brain-damaged (RBD) patients to find out whether changing the position of the hands in space influences tactile extinction and denial of ownership to the same extent. Results showed that manipulation of the spatial position of the hands reduces tactile extinction but leaves denial of ownership of the left hand unaffected. Such a dissociation suggests that delusional misperceptions may be independent from somatic neglect and that representation of hands in space and attribution of ownership are dynamically mapped in at least partly separate neural substrates
Influence of sound on texture perception of apples
No full textCrispness perception of dry food could be modulated by the sound the perceiver produces while biting into it [1]). Does sound influence crispness perception for wet food (apples) as well? Does sound have an effect for perceived hardness that, unlike crispness [2], is mainly a mechanical parameter? Sixty-two participants, divided in 3 groups, were asked to bite flesh cylinders sampled from apples with different texture profiles and to rate them for crispness or hardness. Crucially, they could hear the sound (realistic or manipulated) produced while biting only through headphones.
In experiment 1 (E1), participants rated the perceived crispness of ‘Reinette’, ‘Golden’, and ‘Fuji’ apples. High frequencies of sound (2-20 kHz) were reduced (-12 dB or -24 dB) or fed back without any auditory adjustment (realistic sound). In experiment 2 (E2), perceived crispness and hardness of ‘Reinette’ and ‘Fuji’ apples were rated. The sound was either realistic, or reduced (-24 dB), or globally dampened (microphone off). Experiment 3 (E3) had the same conditions as E2 with the difference that white noise was continuously presented through the headphones.
In all experiments, the different apple varieties were correctly discriminated. As for sound manipulation, E1 confirmed its effect on crispness perception: Apples were rated less crispy when both sound reductions were applied than with the realistic sound. In E2, both reduction and dampening of sounds lowered the perceived crispness of apples as compared to the realistic sound. Apples were instead rated less hard with the microphone off than with the real sound. In E3, the effect of sound disappeared for crispness, while it was marginal for hardness: Apples were rated softer only with the microphone off.
This research demonstrates that sound affects perceived crispness also in wet foods. It also demonstrates, for the first time, that such effects can be observed also for mechanical sensory parameters.
[1] Zampini, M., & Spence, C. (2004). The role of auditory cues in modulating the perceived crispness and staleness of potato chips. J. Sens. Stud., 19, 347-363.
[2] Christensen, C.M., & Vickers, Z.M. (1981). Relationships between chewing sounds to judgments of food crispness. J. Food Sci., 46, 574-57
Multisensory modulation of texture perception in apples
Full text linkCrispness is an important texture parameter influencing sensory evaluation of food, as it works as a predictor of overall food quality. Previous research demonstrated that crispness perception of dry foods could be modulated by the sound the perceiver produced while biting into them (1). Therefore, we investigated whether multisensory effects on crispness perception could be extended to wet food (apples). Additionally, we were interested in verifying whether sound could also modulate perceived hardness, given that hardness (unlike crispness; 2) is considered to mainly rely on mechanical cues. Participants here were asked to bite a series of apple cylinders and to rate their crispness or hardness using a rating scale. Crucially, they heard their biting sound (either realistic or manipulated) through headphones. Measures have been replicated with different apple varieties with the aim to study the sound manipulation effect at different intensity levels for crispness and hardness.
In experiment 1, participants evaluated the perceived crispness of cylinders from 3 apple varieties differing in crispness (‘Reinette’-low, ‘Golden’-medium, and ‘Fuji’-high). High frequencies of sound (2-20 kHz) were reduced (-12 dB or -24 dB) or were left unmodified (realistic sound). The results confirmed the role of sound manipulation in crispness perception also in the case of wet food: Apples were perceived as being less crispy when both sound reductions were applied than with the realistic sound. Additionally, apple varieties were correctly perceived as differing in terms of crispness (‘Reinette’<‘Golden’<‘Fuji’).
In experiment 2, participants evaluated the perceived crispness and hardness of cylinders obtained from apples differing both in crispness and in hardness (‘Reinette’-low vs. ‘Fuji’-high). Sound manipulation consisted in presenting the realistic sound, or in reducing high frequencies of -24 dB, or else in switching the microphone off (thus dampening the acoustic cues overall). The results for both crispness and hardness confirmed that apples were rated significantly different (‘Fuji’ was perceived as the hardest and most crispy). As for sound, any reduction (-24 dB or microphone off) in the auditory information lowered the perceived crispness of apples as compared to the realistic sound. Interestingly, apples were perceived as being less hard when the microphone was switched off than when the real sound was presented. This supports the existence of multisensory effects of sound also for mechanical texture parameters.
In experiment 3, participants underwent the same conditions as in experiment 2 with the sole difference of white noise being continuously presented through the headphones. The volume was such as to try and cover any sounds coming from outside the headphones. The results replicated those obtained in experiment 2 as to the effects of apples both for crispness and for hardness. The effect of sound, though, disappeared for crispness, while it was marginal for hardness (with apples judged as being softer only with the microphone switched off).
This research effectively extends to wet foods the study of sound effects on perceived crispness. Additionally, it demonstrates for the first time that such multisensory effects can be highlighted in evaluations considered as being mainly guided by mechanical cues.
REFERENCES
(1) Zampini, M., & Spence, C. (2004). The role of auditory cues in modulating the perceived crispness and staleness of potato chips. Journal of Sensory Studies, 19, 347-363.
(2) Christensen, C. M., Vickers, Z. M. (1981). Relationships between chewing sounds to judgments of food crispness. Journal of Food Science, 46, 574-578
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Olfactory modulation of visual attention and preference towards congruent food products: an eye tracking study
No full textIn multisensory environments, odours often accompany visual stimuli, directing attention towards congruent objects. While previous research shows that people fixate longer on objects that match a recently smelled odour, it remains unclear whether odours directly influence product choices. Since odours persist in real-world settings, we investigated the effects of repeated odour exposure on visual attention and product choice, accounting for potential olfactory habituation. In a within-participant design, 30 participants completed a task where either a lemon odour (experimental condition) or clean air (control) was paired with congruent lemon-based food images, which varied to prevent visual habituation. We measured eye movements and choice preferences for these food products. Results revealed that participants exhibited longer gaze durations and more frequent fixations on food products congruent with the lemon odour. Repeated odour exposure had no effect on gaze patterns, as participants consistently focused on odour-congruent products throughout the experiment. The intensity and pleasantness of the lemon odour remained stable over time, suggesting no olfactory habituation occurred with this food-related odour. Despite this stable visual attention and odour intensity and pleasantness, participants began to diversify their product choices, selecting fewer odour-congruent items over time. These findings suggest that while odours continue to direct attention towards matching products, repeated exposure may reduce their influence on product choice, highlighting the complex role of olfactory stimuli in decision-making. The study provides insights into how odours interact with visual cues and influence consumer behaviour in prolonged exposure scenario
Neuropsychological evidence that somatic stimuli are spatially coded accord to multiple frames of reference in a stroke patient with tactile extinction.
No full textA right-brain damaged patient with pure tactile extinction was asked to report series of single or double light, brief touches delivered to both hands, the thumb or the pinkie of a single hand, the sides of a single index. The stimulated hand was positioned palm up or palm down, in front of or behind the patient, in anatomic or crossed position. In double touch conditions, stimuli coded as left-sided were extinguished not only when delivered to both hands, but also when delivered on a single hand or a single finger. The findings suggest that tactile stimuli may be coded as left or right according to multiple body anchors that are dynamically scaled from the corporeal midline, to axes centered on a single hand or finger. (C) 2000 Elsevier Science Ireland Ltd
- …
