Search results for "motion"
showing 10 items of 4368 documents
Motion detection in goldfish investigated with the optomotor response is “color blind”
1996
AbstractThe action spectrum of the optomotor response in goldfish was measured to investigate which of the four cone types involved in color vision contributes to motion detection. In the dark-adapted state, the action spectrum showed a single maximum in the range of 500–520 nm, and resembled the rod spectral sensitivity function. Surprisingly, the action spectrum measured in the light-adapted state also revealed a single maximum only, located in the long wavelength range between 620 and 660 nm. A comparison with spectral sensitivity functions of the four cone types suggests that motion detection is dominated by the L-cone type. Using a two colored, “red-green” cylinder illuminated with two…
Malestar emocional y percepción de amenaza en familiares de personas afectadas por COVID-19
2021
Los familiares de personas afectadas por la COVID-19 pudieron experimentar mayor impacto emocional durante el confinamiento, más aún si se tenía una imagen muy amenazante del COVID-19. El objetivo fue analizar la relación entre la psicopatología y la percepción de amenaza en familiares de personas afectadas por COVID-19. Participaron 50 familiares de personas afectadas por COVID-19 (84% mujeres), de entre 20 y 63 años (M=36,88; DT=12,73). Se evaluó la psicopatología (SCL-90-R; Derogatis, Lipman y Covi, 1973) y la percepción de amenaza del COVID (BIP-Q5; Pérez-Fuentes, Molero, Oropesa et al., 2020). Observamos una afectación emocional y una percepción de amenaza moderadas. Quienes tenían enf…
Social Cognition in Neurodevelopmental Disorders and Epilepsy
2021
Introduction: The purpose of our study was to perform a comparative analysis of social cognition in children and adolescents with epilepsy, autism spectrum disorder (ASD), specific learning disorder (SLD) and in typical development (TD) controls. The secondary aim was to relate social cognition to some clinical and demographic characteristics.Methods: Our work is a transversal observational study. The recruits were 179 children and adolescents aged between 6 and 18 years diagnosed with epilepsy, ASD, or SLD and 32 subjects with TD. All the participants underwent neuropsychological assessment of Emotion Recognition (ER) and Theory of Mind (ToM) skills.Results: All three clinical groups perfo…
Emotional modulation of the attentional blink and the relation to interpersonal reactivity
2013
The extent of the attentional blink effect on detection rates in rapid serial visual presentations is modulated by the emotionality of the stimuli. Emotionally salient stimuli are detected more often, even if presented in the attentional blink period, and elicit an enlarged P3 response, which has been interpreted as enhanced consolidation. This effect correlates with individual differences in trait affectivity such as anxiety or dysphoria. Here, we ask if it is also related to the capacity to detect emotions in others, i.e., to interpersonal social traits. We therefore presented emotional and neutral images depicting social scenes as targets in an attentional blink design and measured detec…
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…
Interaction of sight and sound in the perception and experience of musical performance
2016
Recently, Vuoskoski, Thompson, Clarke, and Spence (2014) demonstrated that visual kinematic performance cues may be more important than auditory performance cues in terms of observers’ ratings of expressivity perceived in audiovisual excerpts of piano playing, and that visual kinematic performance cues had crossmodal effects on the perception of auditory expressivity. The present study was designed to extend these findings, and to provide additional information about the roles of sight and sound in the perception and experience of musical performance. Experiment 1 investigated the relative contributions of auditory and visual kinematic performance features to participants’ subjective emotio…
Visually induced motion sickness and presence in videogames: The role of sound
2012
Visually induced motion sickness (VIMS) is a well-known phenomenon in virtual environments, simulators, and videogames. We conducted an experiment to analyze the role of sound on the severity of VIMS and the feeling of presence in videogames. Thirty-two subjects first watched a pre-recorded sequence of the game “Mirrors Edge” and then played the game actively. Game-play sound was activated for half of the participants. VIMS was measured via the Simulator Sickness Questionnaire and the Fast Motion Sickness Scale, presence was captured using the Presence Questionnaire. Results showed severe VIMS in all participants during the passive video session, whereas active-play revealed only moderate …
Grain boundary ridges slow dawn grain boundary motion: In-situ observation
2014
Abstract The impact of grain boundary (GB) ridge on motion of high-angle GB in Zn was studied. The steady-state motion of faceted GB half-loop with [ 10 1 ¯ 0 ] tilt GB and GB ridge was recorded in-situ. The temperatures of faceting–roughening transition were experimentally defined for three GB half-loops. Above the transition temperature GB half-loops had GB “rough-to-rough” ridge with continuously curved GB segments. Below the transition temperature a facet appeared and coexisted with two “facet-to-rough” ridges. For the first time we could extract mobility of “rough-to-rough” and “rough-to-facet” ridges and bring out clearly that GB ridge slows down GB motion. Present removes contradicti…
Sound Event Envelope Estimation in Polyphonic Mixtures
2019
Sound event detection is the task of identifying automatically the presence and temporal boundaries of sound events within an input audio stream. In the last years, deep learning methods have established themselves as the state-of-the-art approach for the task, using binary indicators during training to denote whether an event is active or inactive. However, such binary activity indicators do not fully describe the events, and estimating the envelope of the sounds could provide more precise modeling of their activity. This paper proposes to estimate the amplitude envelopes of target sound event classes in polyphonic mixtures. For training, we use the amplitude envelopes of the target sounds…
An automatic approach for rill network extraction to measure rill erosion by terrestrial and low‐cost unmanned aerial vehicle photogrammetry
2019
For an erosion event (October 2016) occurred at the Sparacia experimental area (Southern Italy), both terrestrial and low-altitude aerial surveys were carried out by consumer grade camera and quadcopter (low-cost unmanned aerial vehicle [UAV]) to measure rill erosion on two plots with steepness of 22% and 26%. Applying the structure from motion (SfM) technique, the three-dimensional digital terrain models (3D-DTMs) and the quasi three-dimensional models (2.5D-digital elevation model [DEM]) were obtained by the two surveys. Furthermore, 3D-DTM and DEM were built using the available aerial photographs (166) and adding 40 terrestrial photographs. For the first time, the convergence index was a…