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In psychology, researchers often rely on face photographs to study face perception. However, finding suitable face stimuli for experiments is often challenging. Computer-generated (CG) faces have emerged as a potential solution due to their flexibility and controllability. However, it has been suggested that these stimuli are evaluated and processed differently from real faces, and their suitability as alternatives in experimental settings remains unclear. To address this, two studies were conducted to examine the impact of CG faces' realism and observers’ self-reported exposure to CG faces on faces appraisals (Study 1) and processing (Study 2). In Study 1 (n = 97), we assessed perceptions of both real and CG faces. Findings indicated that participants generally viewed CG faces less favourably, especially when these faces lacked realism. This trend was particularly pronounced among individuals less exposed to digital characters. In Study 2 (n = 33), we examined the recognition accuracy of these faces in a memory task. The data revealed that CG faces, especially those less realistic, were less accurately recognized. However, this discrepancy was primarily observed among individuals with limited exposure to digital characters, while those more familiar with such characters showed no significant difference in recognition. Overall, this work confirmed that, to date, CG faces are not an adequate alternative to real faces and that researchers should be cautious when using these stimuli in experiments involving face processing. However, as digital graphics improve and as digital characters become more commonplace in daily life, the perceptual gap between CG and real faces may diminish.

Immersive virtual reality (IVR) technology provides several educational affordances that make it a valuable tool for learning, especially from a constructivist learning perspective. Combined with the increasing availability of Metaverse social platforms, such as ENGAGE and AltSpace VR, where students and teachers can meet and work together, IVR may transform how students learn and interact with educational content. However, little is known about students’ attitudes toward IVR in education. To address this gap, we surveyed 329 undergraduate students from different universities in Italy. We used the Unified Theory of Acceptance and Use of Technology (UTAUT) to predict students’ intention to adopt IVR for learning. We further explored the role that different individual factors, including students’ learning styles, affordances perceptions, and personal innovativeness, have on their attitudes toward IVR. A hierarchical multiple regression analysis revealed that the four constructs of the UTAUT, namely performance expectancy, effort expectancy, social influence, and facilitating conditions were the strongest predictors of students’ intention to use IVR in education and that individual factors only had little impact on it. Based on these results, this study provides helpful indications for researchers and educators who wish to introduce IVR effectively in educational contexts. Given the new possibilities provided by Metaverse applications based on IVR technology for learning, it is indeed crucial to fully understand the attitudes different stakeholders in education have toward adopting this technology in educational contexts.

Immersive virtual reality (IVR) technology provides several educational affordances that make it a valuable tool for learning, especially from a constructivist learning perspective. Combined with the increasing availability of Metaverse social platforms, such as ENGAGE and AltSpace VR, where students and teachers can meet and work together, IVR may transform how students learn and interact with educational content. However, little is known about students' attitudes toward IVR in education. To address this gap, we surveyed 329 undergraduate students from different universities in Italy. We used the Unified Theory of Acceptance and Use of Technology (UTAUT) to predict students' intention to adopt IVR for learning. We further explored the role that different individual factors, including students' learning styles, affordances perceptions, and personal innovativeness, have on their attitudes toward IVR. A hierarchical multiple regression analysis revealed that the four constructs of the UTAUT, namely performance expectancy, effort expectancy, social influence, and facilitating conditions were the strongest predictors of students' intention to use IVR in education and that individual factors only had little impact on it. Based on these results, this study provides helpful indications for researchers and educators who wish to introduce IVR effectively in educational contexts. Given the new possibilities provided by Metaverse applications based on IVR technology for learning, it is indeed crucial to fully understand the attitudes different stakeholders in education have toward adopting this technology in educational contexts.

Recently, virtual faces are often used as stimuli to replace traditional photographs in human face perception studies. However, despite being increasingly human-like and realistic, they still present flaws in their aspects that might elicit eerie feelings in the observers, known as the Uncanny Valley (UV) effect. The current systematic review offers a qualitative synthesis of empirical studies investigating observers’ subjective experience with virtual compared to real faces to discuss the possible challenges that the UV effect poses when virtual faces are used as stimuli to study face perception. Results: revealed that virtual faces are judged eerier than real faces. Perception of uncanniness represents a challenge in face perception research as it has been associated with negative emotions and avoidance behaviors that might influence observers’ responses to these stimuli. Also, observers perceive virtual faces as more deviating from familiar patterns than real faces. Lower perceptual familiarity might have several implications in face perception research, as virtual faces might be considered as a category of stimuli distinct from real faces and therefore processed less efficiently. In conclusion, our findings suggest that researchers should be cautious in using these stimuli to study face perception.

L'attenzione sostenuta, la capacità di mantenere l'attenzione su un compito per un periodo di tempo prolungato senza distrarsi, è alla base di molte attività quotidiane. I questionari di autovalutazione tipicamente usati per misurarla presentano notevoli limiti: valutare la propria attenzione durante lo svolgimento di un compito può interferire con il compito stesso, mentre valutarla a posteriori difficilmente permette di coglierne i cambiamenti nel tempo. Al contrario, alcuni parametri fisiologici potrebbero costituire una misura oggettiva dell’attivazione cognitiva nel tempo senza alterare l’attività svolta. La recente disponibilità di strumenti accurati e poco invasivi per registrare questi parametri permetterebbe di studiarli anche in situazioni più vicine all’esperienza quotidiana. Questo studio mira a validare, come indicatori di attenzione sostenuta, misure basate sulla variabilità della frequenza cardiaca e della conduttanza cutanea. Un gruppo di 30 partecipanti volontari (20-28 anni) ha eseguito al computer due test neuropsicologici di attenzione sostenuta: il Jumping Square Task e il Sustained-Pace Finger Tapping task, indossando contemporaneamente un device da polso per la registrazione dei parametri fisiologici. La capacità di attenzione sostenuta è stata operazionalizzata dal punto di vista comportamentale come il cambiamento in correttezza e in tempi di risposta tra la prima e la seconda metà di ciascun compito. I parametri fisiologici sono stati analizzati in modo analogo. I risultati mostrano un'associazione, anche se moderata, tra la capacità di attenzione cognitiva e il cambiamento nei parametri fisiologici.

Both visuo-spatial neglect and visual extinction may occur following right-brain damage. So far, studies on brain-damaged patients have not provided definite evidence about which lesion patterns may lead to the association or dissociation of these deficits. This study was set out to address this issue using Intracranial Electrical Stimulation (IES) in a group of nine patients affected by refractory epilepsy. Cerebral regions associated with visuo-spatial neglect and visual extinction were stimulated, including the right frontal, temporal, and posterior parietal areas. During IES, patients with intracranial implantation involving at least one of these cortical regions were administered with a manual line bisection task (N = 9) to assess visuo-spatial neglect, and a computerized task (N = 8) assessing visual extinction. Results showed that parietal IES induced a rightward bias at the manual bisection task, together with a general improvement in reaction times at bilateral and unilateral visual stimuli detection at the extinction task. The occurrence of visual extinction did not vary across stimulations. By adopting a complementary approach to anatomo-clinical correlation studies, our work corroborates the notion that lesions to the right inferior parietal lobule play a pivotal role in the pathogenesis of visuo-spatial neglect. Importantly, our results also suggest that temporarily interfering with the activity of this region is not sufficient per se to generate visual extinction, which instead may involve a broader and/or different network, possibly extending beyond the cerebral regions considered here, posing important theoretical and clinical implications.

The right hemisphere is involved with the integrative processes necessary to achieve global coherence during reasoning and discourse processing. Specifically, the right temporal lobe has been proven to facilitate the processing of distant associate relationships, such as generating novel ideas. Previous studies showed a specific swing of alpha and gamma oscillatory activity over the right parieto-occipital lobe and the right anterior temporal lobe respectively, when people solve semantic problems with a specific strategy, i.e., insight problem-solving. In this study, we investigated the specificity of the right parietal and temporal lobes for semantic integration using transcranial Random Noise Stimulation (tRNS). We administered a set of pure semantics (i.e., Compound Remote Associates [CRA]) and visuo-semantic problems (i.e., Rebus Puzzles) to a sample of 31 healthy volunteers. Behavioral results showed that tRNS stimulation over the right temporal lobe enhances CRA accuracy (+12%), while stimulation on the right parietal lobe causes a decrease of response time on the same task (−2,100 ms). No effects were detected for Rebus Puzzles. Our findings corroborate the involvement of the right temporal and parietal lobes when solving purely semantic problems but not when they involve visuo-semantic material, also providing causal evidence for their postulated different roles in the semantic integration process and promoting tRNS as a candidate tool to boost verbal reasoning in humans.

I volti sono tra gli stimoli visivi più rilevanti per l’uomo poiché comunicano aspetti chiave per le interazioni sociali. In psicologia, i meccanismi di percezione dei volti vengono tradizionalmente studiati mostrando ai partecipanti fotografie di volti e registrando le loro risposte comportamentali e neurofisiologiche. Recentemente, in alcuni studi le fotografie sono state sostituite da volti virtuali creati attraverso programmi di grafica digitale. Tuttavia, è stato suggerito che questi stimoli potrebbero essere valutati ed elaborati diversamente dai volti reali. Alcuni studi hanno ipotizzato che queste differenze potrebbero essere legate sia al grado di realismo, definito dalla qualità grafica, con cui vengono creati i volti virtuali, sia all'esperienza degli individui con questi stimoli, in termini di frequenza di esposizione. I risultati sono limitati e inconsistenti e non è tuttora chiaro qualora l’utilizzo dei volti virtuali in studi sperimentali rappresenti una valida alternativa ai volti reali. Questa tesi di dottorato mira a fornire una visione più approfondita del ruolo del realismo e dell’esperienza sulla valutazione (Capitolo 1 e Capitolo 2) e il riconoscimento (Capitolo 3) dei volti virtuali. Nel Capitolo 1 viene descritta una revisione della letteratura condotta per stabilire il legame tra i volti virtuali e l’effetto uncanny valley, secondo cui le entità artificiali antropomorfe altamente realistiche scaturiscono delle sensazioni di spiacevolezza e repulsione in chi le osserva. I risultati hanno confermato che i volti virtuali vengono giudicati più inquietanti e meno familiari dei volti reali e che ciò potrebbe derivare da delle discrepanze nel livello di realismo dei volti virtuali percepite dagli osservatori. La revisione ha inoltre sottolineato che, ad oggi, quasi nessun studio ha considerato l’esperienza dei partecipanti con i personaggi virtuali come possibile interpretazione dei risultati. Nel Capitolo 2 sono presentati i risultati di, Faces are among the most relevant visual stimuli for humans as they communicate key aspects essential for social interactions. In psychology, the mechanisms of face perception are traditionally investigated by showing individuals photographs of faces and measuring their behavioral and neurophysiological responses. Recent studies have replaced photographs with virtual faces generated using digital graphics programs. However, it has been suggested that these stimuli might be evaluated differently and elaborated less efficiently than real faces. Some researchers have hypothesized that these differences might be related either to the realism, in terms of render quality, of the virtual faces or to individuals’ expertise with virtual face, in terms of frequency of exposure to these stimuli. However, results are limited and inconsistent and it remains unclear whether virtual faces represent suitable alternatives to real faces in experimental studies. This doctoral dissertation aimed to provide a deeper insight into the role of realism and expertise on virtual faces' evaluation (Chapter 1 and Chapter 2) and recognition (Chapter 3). Chapter 1 described a literature review conducted to establish the link between virtual faces and the uncanny valley effect, according to which highly realistic artificial entities evoke an adverse reaction in the viewer. The results confirmed that virtual faces were judged eerier and less familiar than real faces and that these differences mainly resulted from observers’ perceived inconsistencies in the level of realism of virtual faces. The review further revealed that, so far, nearly no studies considered participants’ expertise with digital characters when analyzing observers’ evaluations of virtual faces. Chapter 2 presented the results of a survey that collected individuals’ judgments of real and virtual faces. Results indicated that virtual faces were judged less reassuring, likable, attractive, trustworthy, and memorable than real faces.