1,720,959 research outputs found
Expectations and Beliefs in Immersive Virtual Reality Environments: Managing of Body Perception
No full textReal and Perceived Feet Orientation Under Fatiguing and Non-Fatiguing Conditions in an Immersive Virtual Reality Environment
ABSTRACT
Lower limbs position sense is a complex yet poorly understood mechanism, influenced by many factors. Hence, we investigated the position sense of lower limbs through feet orientation with the use of Immersive Virtual Reality (IVR). Participants had to indicate how they perceived the real 1050 orientation of their feet by orientating a virtual representation of the feet that was shown in an IVR 1051 scenario. We calculated the angle between the two virtual feet (α-VR) after a high-knee step-in-1052 place task. Simultaneously, we recorded the real angle between the two feet (α-R) (T1). Hence, we 1053 assessed if the acute fatigue impacted the position sense. The same procedure was repeated after 1054 inducing muscle fatigue (T2) and after 10 minutes from T2 (T3). Finally, we also recorded the time 1055 needed to confirm the perceived position before and after the acute fatigue protocol. Thirty healthy 1056 adults (27.5 ± 3.8: 57% female, 43% male) were immersed in an IVR scenario with a representation 1057 of two feet. We found a mean difference between α-VR and α-R of 20.89° [95% CI: 14.67°, 27.10°] 1058 in T1, 16.76° [9.57°, 23.94°] in T2, and 16.34° [10.00°, 22.68°] in T3. Participants spent 12.59, 17.50 1059 and 17.95 seconds confirming the perceived position of their feet at T1, T2, T3, respectively. 1060 Participants indicated their feet as forwarding parallel though divergent, showing a mismatch in the 1061 perceived position of feet. Fatigue seemed not to have an impact on position sense but delayed the 1062 time to accomplish this task.The Effect of Context on Eye-Height Estimation in Immersive Virtual Reality: a Cross-Sectional Study
ABSTRACT
Eye-height spatial perception provides a reference to scale the surrounding environment. It is the result of the integration of visual and postural information. When these stimuli are discordant, the perceived spatial parameters are distorted. Previous studies in immersive virtual reality (IVR) showed that spatial perception is influenced by the visual context of the environment. Hence, this study explored how manipulating the context in IVR affects individuals’ eye-height estimation. Two groups of twenty participants each were immersed in two different IVR environments, represented by a closed room (Wall - W) and an open field (No Wall - NW). Under these two different conditions, participants had to adjust their virtual perspective, estimating their eye height. We calculated the perceived visual offset as the difference between virtual and real eye height, to assess whether the scenarios and the presence of virtual shoes (Feet, No Feet) influenced participants’ estimates at three initial offsets (+100 cm, +0 cm, -100 cm). We found a mean difference between the visual 1679 offsets registered in those trials that started with 100 cm and 0 cm offsets (17.24 cm [8.78; 25.69]) 1680 and between 100 cm and -100 cm offsets (22.35 cm [15.65; 29.05]). Furthermore, a noticeable mean difference was found between the visual offsets recorded in group W, depending on the presence or absence of the virtual shoes (Feet VS No Feet: -6.12 [-10.29, -1.95]). These findings describe that different contexts influenced eye-height perception.Positive Expectations led to Motor Improvement: an Immersive Virtual Reality Pilot Study
ABSTRACT
This pilot study tested the feasibility of an experimental protocol that evaluated the effect of different positive expectations (verbal and visual-haptic) on anterior trunk flexion. Thirty-six participants were assigned to 3 groups (G0, G+ and G++) that received a sham manoeuvre while immersed in Immersive Virtual Reality (IVR). In G0, the manouvre was paired with by neutral verbal statement. In G+ and G++ the manouvre was paired with a positive verbal statement, but only G++ received a visual-haptic illusion. The illusion consisted of lifting a movable tile placed in front of the participants, using its height to raise the floor level in virtual reality. In this way, participants experienced the perception of touching the floor, through the tactile and the virtual visual afference. The distance between fingertips and the floor was measured before, immediately after, and after 5 minutes from the different manouvres. A major difference in anterior trunk flexion was found for G++ compared to the other groups, although it was only significant compared to G0. This result highlighted the feasibility of the present study for future research on people with mobility limitations (e.g., low back pain or kinesiophobia) and the potential role of a visual-haptic illusion in modifying the performance of trunk flexion
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
Unraveling Negative Expectations and Nocebo-Related Effects in Musculoskeletal Pain
No full textThis Perspective adapts the ViolEx Model, a framework validated in several clinical conditions, to better understand the role of expectations in the recovery and/or maintenance of musculoskeletal (MSK) pain. Here, particular attention is given to the condition in which dysfunctional expectations are maintained despite no longer being supported by confirmatory evidence (i.e., belief-lifting the arm leads to permanent tendon damage; evidence-after the patient lifts the arm no tendon damage occurs). While the ViolEx Model suggests that cognitive immunization strategies are responsible for the maintenance of dysfunctional expectations, we suggest that such phenomenon can also be understood from a Bayesian Brain perspective, according to which the level of precision of the priors (i.e., expectations) is the determinant factor accounting for the extent of priors' updating (i.e., we merge the two frameworks, suggesting that highly precise prior can lead to cognitive immunization responses). Importantly, this Perspective translates the theory behind these two frameworks into clinical suggestions. Precisely, it is argued that different strategies should be implemented when treating MSK pain patients, depending on the nature of their expectations (i.e., positive or negative and the level of their precision)
What physiotherapists specialized in orthopedic manual therapy know about nocebo-related effects and contextual factors: findings from a national survey
Full text linkObjective The aim of this study was to investigate the knowledge of orthopedic manual therapists (OMTs) regarding context factors (CFs) capable of triggering nocebo effects during the treatment and how this knowledge is related to their socio-demographic features. Design A cross-sectional online survey. Setting National. Main Outcome Measures A 20 items questionnaire composed by open-ended and closed single-choice questions was administered to explore: (a) socio-demographic variables (10 questions); (b) the relation between different CFs and nocebo-related effects (2 questions); and (c) the knowledge of participants about nocebo-related effects and how they managed them in the clinical practice (8 questions). Participants 1288 OMTs were recruited from the database of the Master in Rehabilitation of Musculoskeletal Disorders (MRDM) of the University of Genova from March to May 2019. Inclusion criteria were: (a) to possess a valid email account; (b) to understand and use as a native language the Italian; (c) to be graduated as OMTs; and (d) to be employed as physiotherapists specialized-OMTs during the survey. Results 791 responses were received (61.4%); 473 of them were male (59.8%), with an average age of 31.0 +/- 7.1 years. OMTs defined nocebo-related effects as the psychosocial context effects around therapy and patient with specific biological bases (72.2%). OMTs know that their clinical practice is pervaded by nocebo-related effects (42.5%), triggered by CFs. Participants communicated nocebo-related effects balancing the positive features of the therapy with the negative ones (50.9%), during the decision of the therapeutic plan (42.7%). They reported associative learning as the main mechanism involved in nocebo-related effects (28.8%). OMTs taught and trained patient's strategies to manage nocebo-related effects (39.6%) through an evaluation and correction of patient's anxieties, doubts and expectations (37.7%). OMTs most frequently considered themselves to have a "medium" education about nocebo-related effects (48.2%) and that their management should be taught during bachelor (78.6%). Conclusion OMTs believed that nocebo-related effects were present in their clinical practice and that they can be triggered by CFs
Giving an account of patients' experience: A qualitative study on the care process of hip and knee osteoarthritis
Full text linkIntroduction: Despite the publication of clinical practice guidelines, the quality of the care process as experienced by patients with osteoarthritis (OA) appears suboptimal. Hence, this study investigates how patients with OA experience their disease and care process, highlighting potential elements that can enhance or spoil it, to optimise their quality of care. Methods: A qualitative study based on semi-structured interviews. Patients with hip and knee OA in Italy were interviewed. The interview guide was created by a pool of health professionals and patients. The interviews were analysed through a theme-based analysis following a philosophy of descriptive phenomenological research. Results: Our analysis revealed seven main themes: (1) Experiencing a sense of uncertainty, as interviewees perceived treatment choices not to be based on medical evidence; (2) Establishing challenging relationships with the self and the other, as they did not feel understood and felt ashamed or hopeless about their condition; (3) Being stuck in one's own or the health professionals' beliefs about the disease management, as a common thought was the perception of movement as something dangerous together with a frequent prescription of passive therapies; (4) Dealing with one's own attitudes towards the disease; Understanding (5) the barriers to and (6) the facilitators of the adherence to therapeutic exercise, which revolve around the therapy cost, the time needed and the patients' willingness to change their life habits and (7) Developing an uneasy relationship with food since the diet was considered as something that “you force yourself to follow” and overeating as a way “to eat your feelings”. Conclusion: The lack of clear explanations and a negative attitude towards first-line nonsurgical treatments (mainly physical exercise), which are considered as a way to fill the time while waiting for surgery, underlines the importance of providing patients with adequate information about OA treatments and to better explain the role of first-line intervention in the care of OA. This will enhance patient-centred and shared decision-making treatments. Patient Contribution: Patients with hip and knee OA participated in creating the interview and contributed with their experience of their care process
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
Experience of the COVID-19 pandemic as lived by patients with hip and knee osteoarthritis : an Italian qualitative study
Full text linkOBJECTIVE: To examine the experience of the COVID-19 pandemic as lived by people with hip and knee osteoarthritis (OA), in Italy.DESIGN: A qualitative study based on semi-structured interviews.SETTING: Urban and suburban areas in northern Italy.PARTICIPANTS: A total of 11 people with OA were enrolled through a purposeful sampling and completed the study.PRIMARY OUTCOME MEASURE: The experience of Italian people with OA during the COVID-19 pandemic.RESULTS: Four themes were brought to the forefront from the analysis of the interviews. (1) Being Stressed for the Limited Social Interactions and for the Family Members at High Risk of Infection, as the interviewees were frustrated because they could not see their loved ones or felt a sense of apprehension for their relatives. (2) Recurring Strategies to Cope with the Pandemic such as an active acceptance towards the situation. (3) Being Limited in the Possibility of Undergoing OA Complementary Treatments and Other Routine Medical Visits. (4) Being Unaware of the Importance of Physical Activity as First-Line Interventions which was an attitude already present before the pandemic.CONCLUSION: The COVID-19 pandemic and related restrictions impacted the quality of life and the care of individuals with hip and knee OA. The social sphere seemed to be the most hindered. However, the interviewees developed a good level of acceptance to deal with the pandemic. When it came to their care, they faced a delay of routine medical visits not related to OA and of other complementary treatments (eg, physical therapies) to manage OA. Finally, a controversial result that emerged from these interviews was that first-line interventions for OA (ie, therapeutic exercise) was not sought by the interviewees, regardless of the restrictions dictated by the pandemic. Policy-making strategies are thus necessary to support the awareness of the importance of such interventions
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
- …
