Panagiotis Kourtesis | The American College of Greece Deree College (original) (raw)

Papers by Panagiotis Kourtesis

European journal of investigation in health, psychology and education/European journal of Investigation in health, psychology and education, Mar 19, 2024

Background: Given that VR is applied in multiple domains, understanding the effects of cybersickn... more Background: Given that VR is applied in multiple domains, understanding the effects of cybersickness on human cognition and motor skills and the factors contributing to cybersickness gains urgency. This study aimed to explore the predictors of cybersickness and its interplay with cognitive and motor skills. Methods: 30 participants, 20-45 years old, completed the MSSQ and the CSQ-VR, and were immersed in VR. During immersion, they were exposed to a roller coaster ride. Before and after the ride, participants responded to CSQ-VR and performed VR-based cognitive and psychomotor tasks. Post VR session, participants completed the CSQ-VR again. Results: Motion sickness susceptibility, during adulthood, was the most prominent predictor of cybersickness. Pupil dilation emerged as a significant predictor of cybersickness. Experience in videogaming was a significant predictor of both cybersickness and cognitive/motor functions. Cybersickness negatively affected visuospatial working memory an...

Frontiers in Human Neuroscience, Nov 26, 2019

Gaming Skills Questionnaire, 2024

Given the widespread popularity of videogames, research attempted to assess their effects on cogn... more Given the widespread popularity of videogames, research attempted to assess their effects on cognitive and affective abilities, especially in children and adolescents. Despite numerous correlational studies, robust evidence on the causal relationship between videogames and cognition remains scarce, hindered by the absence of a comprehensive assessment tool for gaming skills across various genres. In a sample of 347 adolescents, this study aimed to develop and validate the Gaming Skill Questionnaire (GSQ) and assess the impact of gaming skills in six different genres (sport, first-person shooters, role-playing games, action-adventure, strategy, and puzzle games) on cognitive and affective abilities of adolescents. The GSQ exhibited strong reliability and validity, highlighting its potential as a valuable tool. Gaming skills positively affected executive function, memory, overall cognition, cognitive flexibility, and emotion recognition, except for empathy. Various game genres had different effects on cognitive and affective abilities, with verbal fluency influenced mainly by sports, executive functions by action, strategy, and puzzle, and emotion recognition positively impacted by action and puzzle but negatively by sports and strategy games. Both age and gaming skills influenced cognitive flexibility, with gaming having a greater effect. These intriguing genre-specific effects on cognitive and affective functioning postulate further research with GSQ's contribution.

Background: Given that VR is used in multiple domains, understanding the effects of cybersickness... more Background: Given that VR is used in multiple domains, understanding the effects of cybersickness on human cognition and motor skills and the factors contributing to cybersickness is becoming increasingly important. This study aimed to explore the predictors of cybersickness and its interplay with cognitive and motor skills. Methods: 30 participants, 20–45 years old, completed the MSSQ and the CSQ-VR, and were immersed in VR. During immersion, they were exposed to a roller coaster ride. Before and after the ride, participants responded to the CSQ-VR and performed VR-based cognitive and psychomotor tasks. After the VR session, participants completed the CSQ-VR again. Results: Motion sickness susceptibility, during adulthood, was the most prominent predictor of cybersickness. Pupil dilation emerged as a significant predictor of cybersickness. Experience with videogaming was a significant predictor of cybersickness and cognitive/motor functions. Cybersickness negatively affected visuospatial working memory and psychomotor skills. Overall the intensity of cybersickness’s nausea and vestibular symptoms significantly decreased after removing the VR headset. Conclusions: In order of importance, motion sickness susceptibility and gaming experience are significant predictors of cybersickness. Pupil dilation appears to be a cybersickness biomarker. Cybersickness affects visuospatial working memory and psychomotor skills. Concerning user experience, cybersickness and its effects on performance should be examined during and not after immersion.

Clinical tools involving immersive virtual reality (VR) may bring several advantages to cognitive... more Clinical tools involving immersive virtual reality (VR) may bring several advantages to cognitive neuroscience and neuropsychology. However, there are some technical and methodological pitfalls. The American Academy of Clinical Neuropsychology (AACN) and the National Academy of Neuropsychology (NAN) raised 8 key issues pertaining to Computerized Neuropsychological Assessment Devices. These issues pertain to: (1) the safety and effectivity; (2) the identity of the end-user; (3) the technical hardware and software features; (4) privacy and data security; (5) the psychometric properties; (6) examinee issues; (7) the use of reporting services; and (8) the reliability of the responses and results. The VR Everyday Assessment Lab (VR-EAL) is the first immersive VR neuropsychological battery with enhanced ecological validity for the assessment of everyday cognitive functions by offering a pleasant testing experience without inducing cybersickness. The VR-EAL meets the criteria of the NAN and AACN, addresses the methodological pitfalls, and brings advantages for neuropsychological testing. However, there are still shortcomings of the VR-EAL, which should be addressed. Future iterations should strive to improve the embodiment illusion in VR-EAL and the creation of an open access VR software library should be attempted. The discussed studies demonstrate the utility of VR methods in cognitive neuroscience and neuropsychology.

IEEE Transactions on Visualization and Computer Graphics, May 1, 2023

European journal of investigation in health, psychology and education/European journal of Investigation in health, psychology and education, Mar 19, 2024

Frontiers in Human Neuroscience, Nov 26, 2019

Gaming Skills Questionnaire, 2024

IEEE Transactions on Visualization and Computer Graphics, May 1, 2023

Virtual Reality Driving Simulation: An experiment pertaining to attentional and executive functioning processes while driving., 2020

A Virtual Reality Driving Simulation designed for an experiment pertaining to attentional and exe... more A Virtual Reality Driving Simulation designed for an experiment pertaining to attentional and executive functioning processes while driving. In this presentation, you may find a description and suggestions on how to design and develop on Unity an immersive virtual reality experiment to assess attentional processes and executive functioning of drivers. The suggestions also include the acquisition of eye-tracking and electroencephalography (EEG) data. The code can be found in my GitHub profile (repository’s URL: https://github.com/PanosCortese/VRDriver)

Introduction to the development of virtual reality software in Unity game engine (Part 3)., 2020

A presentation pertinent to the development of virtual reality (VR) software for research, clinic... more A presentation pertinent to the development of virtual reality (VR) software for research, clinical, and academic purposes. It includes also links to useful online tutorials, webpages, and assets. This presentation is the fourth part of the VR workshops series I ran at the uCreate Studio of the University of Edinburgh.

Introduction to the development of virtual reality software in Unity game engine (Part 2)., 2020

A presentation pertinent to the development of virtual reality (VR) software for research, clinic... more A presentation pertinent to the development of virtual reality (VR) software for research, clinical, and academic purposes. It includes also links to useful online tutorials, webpages, and assets. This presentation is the third part of the VR workshops series I ran at the uCreate Studio of the University of Edinburgh.

Introduction to the development of virtual reality software in Unity game engine (Part 1)., 2020

A presentation pertinent to the development of virtual reality (VR) software for research, clinic... more A presentation pertinent to the development of virtual reality (VR) software for research, clinical, and academic purposes. It includes also links to useful online tutorials, webpages, and assets.This presentation is the second part of the VR workshops series I ran at the uCreate Studio of the University of Edinburgh.

Introduction To Virtual Reality, 2020

A presentation pertinent to the virtual reality (VR) technologies (i.e., history of VR) and the r... more A presentation pertinent to the virtual reality (VR) technologies (i.e., history of VR) and the relevant psychological illusions. This presentation is the first part of the VR workshop series I ran at the uCreate Studio of the University of Edinburgh.

VR Research Methods For Cognitive Sciences, 2020

This presentation covers the following topics relative to VR research methods for Cognitive Neuro... more This presentation covers the following topics relative to VR research methods for Cognitive Neuroscience and Neuropsychology 1. Identification of necessary technological knowledge for the effective implementation of immersive virtual reality research tools without the presence of VR Induced Symptoms and Effects (VRISE) which may compromise both neuropsychological and neuroscientific data. 2. Development and Validation of an evaluation tool (e.g., questionnaire) for the quality of immersive VR research/clinical software in terms of user experience (UX) , game mechanics, in-game assistance, and VRISE. 3. Cost-effective (i.e., without depending on third-parties such as freelancers and software development companies) development of VR-EAL, guidelines for the development of immersive VR research/clinical software.

While user's perception and performance are predominantly examined independently in virtual reali... more While user's perception and performance are predominantly examined independently in virtual reality, the Action-Specific Perception (ASP) theory postulates that the performance of an individual on a task modulates this individual's spatial and time perception pertinent to the task's components and procedures. This paper examines the association between performance and perception and the potential effects that tactile feedback modalities could generate. This paper reports a user study (N=24), in which participants performed a standardized Fitts's law target acquisition task by using three feedback modalities: visual, visuo-electrotactile, and visuo-vibrotactile. The users completed 3 Target Sizes × 2 Distances × 3 feedback modalities = 18 trials. The size perception, distance perception, and (movement) time perception were assessed at the end of each trial. Performance-wise, the results showed that electrotactile feedback facilitates a significantly better accuracy compared to vibrotactile and visual feedback, while vibrotactile provided the worst accuracy. Electrotactile and visual feedback enabled a comparable reaction time, while the vibrotactile offered a substantially slower reaction time than visual feedback. Although amongst feedback types the pattern of differences in perceptual aspects were comparable to performance differences, none of them was statistically significant. However, performance indeed modulated perception. Significant action-specific effects on spatial and time perception were detected. Changes in accuracy modulate both size perception and time perception, while changes in movement speed modulate distance perception. Also, the index of difficulty was found to modulate all three perceptual aspects. However, individual differences appear to affect the magnitude of action-specific effects. These outcomes highlighted the importance of haptic feedback on performance, and importantly the significance of action-specific effects on spatial and time perception in VR, which should be considered in future VR studies.

Immersive virtual reality methods in cognitive neuroscience and neuropsychology: Meeting the criteria of the National Academy of Neuropsychology and American Academy of Clinical Neuropsychology

Electrotactile Feedback For Enhancing Contact Information in Virtual Reality, 2021

This paper presents a wearable electrotactile feedback system to enable precise and accurate cont... more This paper presents a wearable electrotactile feedback system to enable precise and accurate contact rendering with virtual objects for mid-air interactions. In particular, we propose the use of electrotactile feedback to render the interpenetration distance between the user's finger and the virtual content is touched. Our approach consists of modulating the perceived intensity (frequency and pulse width modulation) of the electrotactile stimuli according to the registered interpen-etration distance. In a user study (N=21), we assessed the performance of four different interpenetration feedback approaches: electrotactile-only, visual-only, electrotactile and visual, and no interpenetration feedback. First, the results showed that contact precision and accuracy were significantly improved when using interpenetration feedback. Second, and more interestingly, there were no significant differences between visual and electrotactile feedback when the calibration was optimized and the user was familiarized with electrotactile feedback. Taken together, these results suggest that electrotactile feedback could be an efficient replacement of visual feedback for accurate and precise contact rendering in virtual reality avoiding the need of active visual focus and the rendering of additional visual artefacts.

An ecologically valid examination of event-based and time-based prospective memory using immersive virtual reality: the effects of delay and task type on everyday prospective memory, 2021

Recent research has focused on assessing either event-or time-based prospective memory (PM) using... more Recent research has focused on assessing either event-or time-based prospective memory (PM) using laboratory tasks. Yet, the findings pertaining to PM performance on laboratory tasks are often inconsistent with the findings on corresponding naturalistic experiments. Ecologically valid neuropsychological tasks resemble the complexity and cognitive demands of everyday tasks, offer an adequate level of experimental control, and allow a generalisation of the findings to everyday performance. The Virtual Reality Everyday Assessment Lab (VR-EAL), an immersive virtual reality neuropsychological battery with enhanced ecological validity, was implemented to comprehensively assess everyday PM (i.e., focal and non-focal event-based, and time-based). The effects of the length of delay between encoding and initiating the PM intention and the type of PM task on everyday PM performance were examined. The results revealed that everyday PM performance was affected by the length of delay rather than the type of PM task. The effect of the length of delay differentially affected performance on the focal, non-focal, and time-based tasks and was proportional to the salience of the PM cue. This study further highlights the necessity of adopting ecological valid paradigms when examining PM performance. Keywords: focal event-based prospective memory; non-focal event-based prospective memory; time-based prospective memory; everyday prospective memory; virtual reality Prospective memory (PM) involves the ability to remember to initiate an action in the future. The PM action may be associated with either a certain event (event-based e.g., when you see Alex, give him this card) or a specific time (time-based e.g., at 3 pm call Anne). The importance of PM tasks in everyday life varies from minimal importance (e.g., watering the plants every second day) to extreme importance (e.g., taking blood-pressure tablets after lunch). Hence, PM is paramount to various aspects of everyday life. Event-based prospective memory The two predominant theoretical models of event-based PM are the preparatory attentional and memory (PAM) the

An ecologically valid examination of the theoretical framework of prospective memory, 2021

Studies on prospective memory (PM) predominantly assess either event- or time-based PM by impleme... more Studies on prospective memory (PM) predominantly assess either event- or time-based PM by implementing non-ecological laboratory-based tasks. The results deriving from these paradigms have provided findings that are discrepant with ecologically valid research paradigms that converge on the complexity and cognitive demands of everyday tasks. The Virtual Reality Everyday Assessment Lab (VR-EAL), an immersive virtual reality (VR) neuropsychological battery with enhanced ecological validity, was implemented to assess everyday event- and time-based PM, as well as the influence of other cognitive functions on everyday PM functioning. The results demonstrated the importance of delayed recognition, planning, and visuospatial attention on everyday PM. Delayed recognition and planning ability were found to be central in event- and time-based PM respectively. In order of importance, delayed recognition, visuospatial attention speed, and planning ability were found to be involved in event-based PM functioning. Comparably, planning, visuospatial attention accuracy, delayed recognition, and multitasking/task-shifting ability were found to be involved in time-based PM functioning. These findings further suggest the importance of ecological validity in the study of PM, which may be achieved using immersive VR paradigms.

Validation of the Virtual Reality Everyday Assessment Lab, 2020

Objective: The assessment of cognitive functions such as prospective memory, episodic memory, att... more Objective: The assessment of cognitive functions such as prospective memory, episodic memory, attention, and executive functions benefits from an ecologically valid approach to better understand how performance outcomes generalize to everyday life. Immersive virtual reality (VR) is considered capable of simulating real-life situations to enhance ecological validity. The present study attempted to validate the Virtual Reality Everyday Assessment Lab (VR-EAL), an immersive VR neuropsychological battery, against an extensive paper-and-pencil neuropsychological battery.

Methods: Forty-one participants (21 females) were recruited: 18 gamers and 23 non-gamers who attended both an immersive VR and a paper-and-pencil testing session. Bayesian Pearson correlation analyses were conducted to assess construct and convergent validity of the VR-EAL. Bayesian t-tests were performed to compare VR and paper-and-pencil testing in terms of administration time, similarity to real life tasks (i.e., ecological validity), and pleasantness.

Results: VR-EAL scores were significantly correlated with their equivalent scores on the paper-and-pencil tests. The participants’ reports indicated that the VR-EAL tasks were significantly more ecologically valid and pleasant than the paper-and-pencil neuropsychological battery. The VR-EAL battery also had a shorter administration time.

Conclusion: The VR-EAL appears as an effective neuropsychological tool for the assessment of everyday cognitive functions, which has enhanced ecological validity, a highly pleasant testing experience, and does not induce cybersickness.

PhD Doctor of Philosophy, 2020

In cognitive neuroscience and neuropsychology, the collection of cognitive and behavioural data i... more In cognitive neuroscience and neuropsychology, the collection of cognitive and behavioural data is predominantly achieved by implementing paper-and-pencil and computerized (i.e., 2D and 3D applications) assessments. However, these psychometric tools in clinics and/or laboratories display several limitations and discrepancies between the observed performance in the laboratory/clinic and the actual performance of individuals in everyday life. The functional and predictive association between an individual's performance on a set of neuropsychological tests and the individual's performance in various everyday life settings is called ecological validity. Ecological validity is considered an important issue that cannot be resolved by the currently available assessment tools. Virtual reality head-mounted displays (HMD) appear to be effective research tools, which may address the problem of ecological validity in neuropsychological testing. However, their widespread implementation is hindered by virtual reality induced symptoms and effects (VRISE) and the lack of skills in virtual reality software development. In this PhD, a technological systematic literature review of the reasons for adverse symptomatology was conducted and suggestions and technological knowledge for the implementation of virtual reality HMD systems in cognitive neuroscience provided. The review indicated features pertinent to display, sound, motion tracking, navigation, ergonomic interactions, user experience, and computer hardware that should be considered by researchers. Subsequently, a meta-analysis of 44 neuroscientific or neuropsychological studies involving virtual reality HMD systems was performed. The meta-analysis of the virtual reality studies demonstrated that new generation HMDs induce significantly less VRISE and marginally fewer dropouts. Importantly, the commercial versions of the new generation HMDs with ergonomic interactions had zero incidents of adverse symptomatology and dropouts. HMDs equivalent to or greater than the commercial versions of contemporary HMDs accompanied with ergonomic interactions are suitable for implementation in cognitive neuroscience. Another aim of this PhD was to devise a brief tool to appraise and report both the quality of software features and VRISE intensity quantitatively; such a tool does not currently exist. The Virtual Reality Neuroscience Questionnaire (VRNQ; Kourtesis et al., 2019) was developed to assess the quality of virtual reality software in terms of user experience, game mechanics, in-game assistance, and VRISE. Forty participants aged between 28 and 43 years were recruited (18 gamers and 22 non-gamers) for the study. They participated in 3 different virtual reality sessions until they felt weary or discomfort and subsequently filled in the VRNQ. The results demonstrated that VRNQ is a valid tool for assessing virtual reality software as it has good convergent, discriminant, and construct validity. The maximum duration of virtual reality sessions should be between 55 and 70 min when the virtual reality software meets or exceeds the parsimonious cut-offs of the VRNQ, and the users are familiarized with the virtual reality system. Also, gaming experience does not affect how long virtual reality sessions should last. Furthermore, while the quality of virtual reality software substantially modulates the maximum duration of virtual reality sessions, age and education do not. Finally, deeper immersion, better quality of graphics and sound, and more helpful in-game instructions and prompts were found to reduce VRISE intensity. The VRNQ facilitates the brief assessment and reporting of the quality of virtual reality software features and/or the intensity of VRISE, while its minimum and parsimonious cut-offs may appraise the suitability of virtual reality software for implementation in research and clinical settings. However, the development of virtual reality software is predominantly dependent on third parties (e.g., freelancers or companies) with programming and software development skills. A solution that will promote the adoption of immersive virtual reality as a research and clinical tool might be the in-house development of virtual reality research/clinical software by computer science literate cognitive scientists or research software engineers. In Chapter 4, guidelines are offered for the development of virtual reality software in cognitive neuroscience and neuropsychology, by describing and discussing the stages of the development of Virtual Reality Everyday Assessment Lab (VR-EAL), the first neuropsychological battery in immersive virtual reality. Techniques for evaluating cognitive functions within a realistic storyline are discussed. The utility of various assets in Unity, software development kits, and other software are described so that cognitive scientists can overcome challenges pertinent to VRISE and the quality of the virtual reality software. In addition, VR-EAL is evaluated in accordance with the necessary criteria for virtual reality software for research purposes. The virtual reality neuroscience questionnaire (VRNQ) was implemented to appraise the quality of the three versions of VR-EAL in terms of user experience, game mechanics, in-game assistance, and VRISE. Twenty-five participants aged between 20 and 45 years with 12-16 years of full-time education evaluated various versions of VR-EAL. The final version of VR-EAL achieved high scores in every sub-score of the VRNQ and exceeded its parsimonious cut-offs. It also appeared to have better in-game assistance and game mechanics, while its improved graphics substantially increased the quality of the user experience and almost eradicated VRISE. The results substantially support the feasibility of the development of effective virtual reality research and clinical software without the presence of VRISE during a 60-min virtual reality session. In Chapter 5, validation of VR-EAL as an assessment of prospective memory, episodic memory, attention, and executive functions using an ecologically valid approach is examined. Performance on the VR-EAL, an immersive virtual reality neuropsychological battery, is examined against an extensive paper-and-pencil neuropsychological battery. Forty-one participants (21 females) were recruited: 18 gamers and 23 non-gamers who attended both an immersive virtual reality and a paper-and-pencil testing session. Bayesian Pearson correlation analyses were conducted to assess construct and convergent validity of the VR-EAL. Bayesian t-tests were performed to compare virtual reality and paper-and-pencil testing in terms of administration time, similarity to real life tasks (i.e., ecological validity), and pleasantness. VR-EAL scores were significantly correlated with their equivalent scores on the paper-and-pencil tests. The participants' reports indicated that the VR-EAL tasks were considered significantly more ecologically valid and pleasant than the paper-and-pencil neuropsychological battery. The VR-EAL battery also had a shorter administration time. The VR-EAL appears to be an effective neuropsychological tool for the assessment of everyday cognitive functions, and has enhanced ecological validity, a highly pleasant testing experience, and does not induce cybersickness. In the final part of this thesis, the preparatory attentional and memory (PAM) and the multiprocess theories of prospective memory are examined by attempting to identify the cognitive functions which may predict the individual's performance on ecologically valid prospective memory tasks in the same group of participants described in Chapter 5. Bayesian t-tests were conducted to explore the differences among different prospective memory tasks (e.g., event-based and time-based) and prospective memory tasks with varying delays between encoding and the recall of the intended action (e.g., short-delay versus long-delay). Bayesian linear regression analyses were performed to examine the predictors of VR-EAL scores. The results revealed that the type of prospective memory task does not play a significant role in everyday prospective memory functioning, but instead the length of delay between encoding and retrieving the prospective memory intention plays a central role. Support for the PAM and MP frameworks was found in non-focal and focal event-based tasks respectively. However, the findings, inferring a dynamic interplay between automatic and intentional monitoring and retrieval processes, agree with the inclusive approach of the multiprocess framework. Also, the role of executive functions appears crucial in everyday PM. Finally, everyday PM is predominantly facilitated by episodic memory, visuospatial attention, auditory attention, and executive functions. In conclusion, this PhD thesis attempted to show how immersive virtual reality research methods may be implemented efficiently without the confounding effect of cybersickness symptomatology in order to enhance the ecological validity of neuropsychological testing and contribute to our understanding of everyday cognitive ability.