Dirk P. Janssen

Switching Modalities in A Sentence Verification Task: ERP Evidence for Embodied Language Processing

In an event related potential (ERP) experiment using written language materials only, we investigated a potential modulation of the N400 by the modality switch effect. The modality switch effect occurs when a first sentence, describing a fact grounded in one modality, is followed by a second sentence describing a second fact grounded in a different modality. For example, “A cellar is dark” (visual), was preceded by either another visual property “Ham is pink” or by a tactile property “A mitten is soft.” We also investigated whether the modality switch effect occurs for false sentences (“A cellar is light”). We found that, for true sentences, the ERP at the critical word “dark” elicited a significantly greater frontal, early N400-like effect (270–370 ms) when there was a modality mismatch than when there was a modality-match. This pattern was not found for the critical word “light” in false sentences. Results similar to the frontal negativity were obtained in a late time window (500–700 ms). The obtained ERP effect is similar to one previously obtained for pictures. We conclude that in this paradigm we obtained fast access to conceptual properties for modality-matched pairs, which leads to embodiment effects similar to those previously obtained with pictorial stimuli.

Subliminal Salience Search Illustrated: EEG Identity and Deception Detection on the Fringe of Awareness

We propose a novel deception detection system based on Rapid Serial Visual Presentation (RSVP). One motivation for the new method is to present stimuli on the fringe of awareness, such that it is more difficult for deceivers to confound the deception test using countermeasures. The proposed system is able to detect identity deception (by using the first names of participants) with a 100% hit rate (at an alpha level of 0.05). To achieve this, we extended the classic Event-Related Potential (ERP) techniques (such as peak-to-peak) by applying Randomisation, a form of Monte Carlo resampling, which we used to detect deception at an individual level. In order to make the deployment of the system simple and rapid, we utilised data from three electrodes only: Fz, Cz and Pz. We then combined data from the three electrodes using Fishers method so that each participant was assigned a single p-value, which represents the combined probability that a specific participant was being deceptive. We also present subliminal salience search as a general method to determine what participants find salient by detecting breakthrough into conscious awareness using EEG.

Countering Countermeasures: Detecting Identity Lies by Detecting Conscious Breakthrough

One major drawback of deception detection is its vulnerability to countermeasures, whereby participants wilfully modulate their physiological or neurophysiological response to critical guilt-determining stimuli. One reason for this vulnerability is that stimuli are usually presented slowly. This allows enough time to consciously apply countermeasures, once the role of stimuli is determined. However, by increasing presentation speed, stimuli can be placed on the fringe of awareness, rendering it hard to perceive those that have not been previously identified, hindering the possibility to employ countermeasures. We tested an identity deception detector by presenting first names in Rapid Serial Visual Presentation and instructing participants to lie about their own identity. We also instructed participants to apply a series of countermeasures. The method proved resilient, remaining effective at detecting deception under all countermeasures.

Playing under threat. Examining stereotype threat in female game players

The present study assesses the impact of stereotype threat on how women experience digital gaming in an evaluative context. By means of a controlled lab experiment, this study tested the effects of reinforcing stereotypical information suggesting that women are less competent players versus the effects of countering this stereotype. In doing so, game leaderboard scores were manipulated distinguishing between Stereotype Neutral (high scores without gender cues), Stereotype Boost (female-dominated high scores) and Stereotype Threat (male-dominated high scores) conditions. Results indicated that gamer identity, trait competitiveness, and playing habits modulate the experience of social identity threat. Performance and affective responses elicited by the Stereotype Threat Condition were more negatively affected in case of strongly identified gamers, highly competitive women, and/or avid players when compared with the other conditions. However, virtually no differences were observed when comparing the Stereotype Neutral and Stereotype Boost conditions. Overall, the present study demonstrates the existence of the stereotype threat mechanism and how this undermines the game experience of female players within digital game culture. Investigating stereotype threat in the context of women playing games.Womens gamer identity and play habits as important moderators for threat effects.Worse performance in threat condition compared to neutral and boost conditions.Increased negative affect in threat condition compared to neutral and boost conditions.Female role modeling does not guarantee improved performance or affective responses.

Improving level design through game user research : a comparison of methodologies

In this article we compare the benefits for game design and development relative to the use of three Game User Research (GUR) methodologies (user interviews, game metrics, and psychophysiology) to assist in shaping levels for a 2-D platformer game. We illustrate how these methodologies help level designers make more informed decisions in an otherwise qualitative design process. GUR data sources were combined in pairs to evaluate their usefulness in small-scale commercial game development scenarios, as commonly used in the casual game industry. Based on the improvements suggested by each data source, three levels of a Super Mario clone were modified and the success of these changes was measured. Based on the results we conclude that user interviews provide the clearest indications for improvement among the considered methodologies while metrics and biometrics add different types of information that cannot be obtained otherwise. These findings can be applied to the development of 2-D games; we discuss how other types of games may differ from this. Finally, we investigate differences in the use of GUR methodologies in a follow-up study for a commercial game with children as players.

Comparing Game User Research Methodologies for the Improvement of Level Design in a 2-D Platformer

In this paper we compare the effects of using three game user research methodologies to assist in shaping levels for a 2-D platformer game, and illustrate how the use of such methodologies can help level designers to make more informed decisions in an otherwise qualitative oriented design process. Game user interviews, game metrics and psychophysiology (biometrics) were combined in pairs to gauge usefulness in small-scale commercial game development scenarios such as the casual game industry. Based on the recommendations made by the methods, three sample levels of a Super Mario clone were improved and the opinions of a second sample of users indicated the success of these changes. We conclude that user interviews provide the clearest indications for improvement among the considered methodologies while metrics and biometrics add different types of information that cannot be obtained otherwise.