1,721,004 research outputs found
Physiological responses related to pleasant and unpleasant sounds
No full textSound is a crucial factor in everyday life, since it impacts on people feelings and reactions to circumstances. Therefore, classifying sounds based on experiential, physiological, and behavioral responses becomes a key factor in the under-standing of the relationship between sound and emotions. As reported in the literature, since using a single type of analysis results to be only partially reliable, there is an increasing demand of integration among the various kind of analyses. The aim of this study is to integrate both physiological and self-reported outcomes, in order to provide a more accurate information about the emotions induced by pleasant and unpleasant audio stimuli. In particular, several indices were extracted from physiological signals, which were matched with self-reported outcomes. The results of this study show that cardiac response in terms of sympathetic activation is significantly different for the two types of acoustic artefacts. To further support the physiological responses results, statistical analysis of Loudness, Roughness and Sharpness values was performed. The two types of stimuli seemed to be characterized by significantly different levels of Loudness and Roughness, which were found higher for unpleasant stimuli. Therefore, it is possible to conclude that only one type of measure is not always sufficient to characterize the emotional response to sounds and more than one measure is needed as indicator of listener emotions
Information Retrieval from Photoplethysmographic Sensors: A Comprehensive Comparison of Practical Interpolation and Breath-Extraction Techniques at Different Sampling Rates
Full text linkThe increasingly widespread diffusion of wearable devices makes possible the continuous monitoring of vital signs, such as heart rate (HR), heart rate variability (HRV), and breath signal. However, these devices usually do not record the “gold-standard” signals, namely the electrocardiography (ECG) and respiratory activity, but a single photoplethysmographic (PPG) signal, which can be exploited to estimate HR and respiratory activity. In addition, these devices employ low sampling rates to limit power consumption. Hence, proper methods should be adopted to compensate for the resulting increased discretization error, while diverse breath-extraction algorithms may be differently sensitive to PPG sampling rate. Here, we assessed the efficacy of parabola interpolation, cubic-spline, and linear regression methods to improve the accuracy of the inter-beat intervals (IBIs) extracted from PPG sampled at decreasing rates from 64 to 8 Hz. PPG-derived IBIs and HRV indices were compared with those extracted from a standard ECG. In addition, breath signals extracted from PPG using three different techniques were compared with the gold-standard signal from a thoracic belt. Signals were recorded from eight healthy volunteers during an experimental protocol comprising sitting and standing postures and a controlled respiration task. Parabola and cubic-spline interpolation significantly increased IBIs accuracy at 32, 16, and 8 Hz sampling rates. Concerning breath signal extraction, the method holding higher accuracy was based on PPG bandpass filtering. Our results support the efficacy of parabola and spline interpolations to improve the accuracy of the IBIs obtained from low-sampling rate PPG signals, and also indicate a robust method for breath signal extraction
Characterization of Eye Gaze and Pupil Diameter Measurements from Remote and Mobile Eye-Tracking Devices
No full textEye-tracking technology allows to capture real-time visual behavior information and to provide insights about cognitive processes and autonomic function, by measuring gaze position and pupillary response to delivered stimuli. Over the recent years, the development of easy-to-use devices led to a large increase in the use of eye-tracking in a broad spectrum of applications, e.g. clinical diagnostics and psychological research. Given the lack of extensive material to characterize the performance of different eye-trackers, especially latest generation devices, the present study aimed at comparing a screen-mounted eye-tracker (remote) and a pair of wearable eye-tracking glasses (mobile). Seventeen healthy subjects were asked to look at a moving target on a screen for 90 s, while point of regard (POR) and pupil diameter (PD) were recorded by the two devices with a sampling rate of 30 Hz. First, data were preprocessed to remove artifacts, then correlation coefficients (for both signals) and magnitude-squared coherence (for PD) were calculated to assess signals agreement in time and frequency domain. POR measurements from remote and mobile devices resulted highly comparable (ρ > 0.75). PD showed lower correlation and major dispersion (ρ > 0.50), besides a higher number of invalid samples from the mobile device with respect to the remote one. Results provided evidence that the two instruments do share the same content at the level of information generally used to characterize subjects behavioral and physiological reactions. Future analysis of additional features and devices with higher sampling frequencies will be planned to further support their clinical use
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
Comparing fundraising campaigns in healthcare using psychophysiological data: a network-based approach
No full textMeasuring the effectiveness of fundraising campaigns is crucial for improving communication strategies. This is particularly pertinent for healthcare campaigns aimed at raising awareness about sensitive health issues that require financial support for advancing research efforts. The present work assesses campaign effectiveness by examining brain activation evoked by different video stimuli. Within a multivariate statistical setting, we compare the physiological responses that are induced by four fundraising campaigns designed under different communication strategies. Specifically, we model attention-related electroencephalographic (EEG) signals using graphical models to estimate partial correlation networks associated with each video campaign. These networks are then compared in terms of structure and connectivity using resampling methods. The proposed approach is flexible, allowing for the analysis of induced physiological responses at both local and global levels. It accounts for the interrelationships among collected EEG data and participants’ heterogeneity, overcoming the need to derive composite scores as is commonly done in neuromarketing research areas. The networks derived from different campaigns exhibit significantly different structures and connectivity, indicating distinct cognitive and emotional responses induced by the videos. Given its generality, our proposed approach can be applied effectively in psychological and neuroscientific research fields whenever the physiological response to affective stimuli is of interest. Graphical abstract: (Figure presented.)
Exploration of the physiological response to an online gambling task by frequency domain analysis of the electrodermal activity
No full textOnline gambling has dramatically increased over the last decades, thus the study of the underlying physiological mechanisms could be helpful to better understand related disorders. Specifically, physiological arousal is well-known to play a key role in gambling behavior. In the present study, unconventional frequency feature of the electrodermal activity (EDA) was extracted (EDASympn) and compared to the most common heart rate variability (HRV) spectral parameters (LF, HF, HFn, LF/HF) to measure arousal during an online gambling session. 46 subjects played online slot machines for 30 minutes, while EDA and ECG were recorded. In the analysis the gaming session was divided into three 10-minutes-long phases. A one-way repeated measures analysis of variance was carried out for each spectral parameter, with the game phases as within-subjects factor. All the calculated parameters showed significant differences between the initial phase of the game and the last two (p < 0.001). In particular, EDAsympn displayed a reciprocal trend with respect to HFn: an initial increase (decrease for HFn) was followed by a plateau phase. LF exhibited a significant difference also between the second and the third phases. EDA frequency-domain analysis appears to be a promising method for physiological arousal assessment, by showing the same discriminative power of HRV spectral components. Further research is needed to emphasize these findings.Clinical Relevance-This promotes the use of a new and easy-to-implement method to assess sympathetic activity
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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