A tutorial: Analyzing eye and head movements in virtual reality.

This tutorial provides instruction on how to use the eye tracking technology built into virtual reality (VR) headsets, emphasizing the analysis of head and eye movement data when an observer is situated in the center of an omnidirectional environment. We begin with a brief description of how VR eye movement research differs from previous forms of eye movement research, as well as identifying some outstanding gaps in the current literature. We then introduce the basic methodology used to collect VR eye movement data both in general and with regard to the specific data that we collected to illustrate different analytical approaches. We continue with an introduction of the foundational ideas regarding data analysis in VR, including frames of reference, how to map eye and head position, and event detection. In the next part, we introduce core head and eye data analyses focusing on determining where the head and eyes are directed. We then expand on what has been presented, introducing several novel spatial, spatio-temporal, and temporal head-eye data analysis techniques. We conclude with a reflection on what has been presented, and how the techniques introduced in this tutorial provide the scaffolding for extensions to more complex and dynamic VR environments.

Large language models have divergent effects on self-perceptions of mind and the attributes considered uniquely human.

The rise of powerful Large Language Models (LLMs) provides a compelling opportunity to investigate the consequences of anthropomorphism, particularly regarding how their exposure may influence the way individuals view themselves (self-perception) and other people (other-perception). Using a mind perception framework, we examined attributions of agency (the ability to do) and experience (the ability to feel). Participants evaluated their agentic and experiential capabilities and the extent to which these features are uniquely human before and after exposure to LLM responses. Post-exposure, participants increased evaluations of their agentic and experiential qualities while decreasing their perception that agency and experience are considered to be uniquely human. These results indicate that anthropomorphizing LLMs impacts attributions of mind for humans in fundamentally divergent ways: enhancing the perception of one's own mind while reducing its uniqueness for others. These results open up a range of future questions regarding how anthropomorphism can affect mind perception toward humans.

Incomplete Faces Do but Masked Faces Do Not Affect Mind Perception.

The human face plays a critical role in how we perceive the minds of others. The current research across two studies explored whether face masks also impact mind perception, with the expectation that they lead to lower attributions of agency and experience to individuals, making them seem less mentally capable due to their association with reduced facial expression perception and impaired communication. In the first study, participants' ratings of masked and unmasked faces for agency and experience did not yield significant differences, suggesting that wearing a face mask does not affect the perception of the mind. To explore whether these findings applied when the lower face was cropped instead of masked, results of the second study showed that removing the lower face led to decreased agency ratings, but similar to the first study, there were no changes in experience ratings. Altogether, our results showed that wearing face masks does not reduce the perception of mental capacity. Moreover, female faces received higher ratings for both agency and experience compared to male faces. The complex relationship between face masks, gender, and mind perception warrants further exploration.

Short-Term Memory Capacity Predicts Willingness to Expend Cognitive Effort for Reward.

We must often decide whether the effort required for a task is worth the reward. Past rodent work suggests that willingness to deploy cognitive effort can be driven by individual differences in perceived reward value, depression, or chronic stress. However, many factors driving cognitive effort deployment-such as short-term memory ability-cannot easily be captured in rodents. Furthermore, we do not fully understand how individual differences in short-term memory ability, depression, chronic stress, and reward anticipation impact cognitive effort deployment for reward. Here, we examined whether these factors predict cognitive effort deployment for higher reward in an online visual short-term memory task. Undergraduate participants were grouped into high and low effort groups (n HighEffort = 348, n LowEffort = 81; n Female = 332, n Male = 92, M Age = 20.37, Range Age = 16-42) based on decisions in this task. After completing a monetary incentive task to measure reward anticipation, participants completed short-term memory task trials where they could choose to encode either fewer (low effort/reward) or more (high effort/reward) squares before reporting whether or not the color of a target square matched the square previously in that location. We found that only greater short-term memory ability predicted whether participants chose a much higher proportion of high versus low effort trials. Drift diffusion modeling showed that high effort group participants were more biased than low effort group participants toward selecting high effort trials. Our findings highlight the role of individual differences in cognitive effort ability in explaining cognitive effort deployment choices.

The medium modulates the medusa effect: Perceived mind in analogue and digital images.

We effortlessly attribute mental states to other people. We also attribute minds to people depicted in pictures, albeit at a reduced strength. Intriguingly, this reduction in intensity continues for images of people within a photograph itself-a phenomenon known as the Medusa effect. The present study replicates the Medusa effect for images shown digitally and on paper. Crucially, we demonstrate that we can reduce the magnitude of the Medusa effect by depicting people digitally within a computer screen (e.g., as if one were interacting with a person on a Zoom call). As well as modulating the quantity of the Medusa effect, changes in pictorial medium can affect the quality of the perceived mind. Specifically, the dimension of Experience-what a depicted person can feel-reflected participants' observations that they could interact with an onscreen person embedded in a digital image. This combination of a robust Medusa effect and the ability to control it both quantitatively and qualitatively opens many avenues for its future application, such as manipulating and measuring mind in immersive media.

Autistic traits and anthropomorphism: the case of vehicle fascia perception.

Individuals high in autistic traits can have difficulties with social interactions which may stem from difficulties with mentalizing abilities, yet findings from research investigating anthropomorphism of non-human objects in high trait individuals are inconsistent. Measuring emotions and attributes of front-facing vehicles, individuals scoring high versus low on the AQ-10 were compared for ratings of angry-happy, hostile-friendly, masculine-feminine, and submissive-dominant, as a function of vehicle size (large versus small). Our results showed that participants perceived large vehicles as more angry, hostile, masculine, and dominant than small vehicles, with no significant difference in ratings between high and low AQ-10 scorers. The current findings support previous research reporting high autistic trait individuals' intact object processing. Our novel findings also suggest high autistic trait individuals' anthropomorphizing abilities are comparable to those found in low autistic trait individuals.

Eyes meet, hands greet: The art of timing in social interactions.

Shaking hands is a fundamental form of social interaction. The current study used high-definition cameras during a university graduation ceremony to examine the temporal sequencing of eye contact and shaking hands. Analyses revealed that mutual gaze always preceded shaking hands. A follow up investigation manipulated gaze when shaking hands, and found that participants take significantly longer to accept a handshake when an outstretched hand precedes eye contact. These findings demonstrate that the timing between a person's gaze and their offer to shake hands is critical to how their action is interpreted.

Turning the (virtual) world around: Patterns in saccade direction vary with picture orientation and shape in virtual reality.

Research investigating gaze in natural scenes has identified a number of spatial biases in where people look, but it is unclear whether these are partly due to constrained testing environments (e.g., a participant with their head restrained and looking at a landscape image framed within a computer monitor). We examined the extent to which image shape (square vs. circle), image rotation, and image content (landscapes vs. fractal images) influence eye and head movements in virtual reality (VR). Both the eyes and head were tracked while observers looked at natural scenes in a virtual environment. In line with previous work, we found a bias for saccade directions parallel to the image horizon, regardless of image shape or content. We found that, when allowed to do so, observers move both their eyes and head to explore images. Head rotation, however, was idiosyncratic; some observers rotated a lot, whereas others did not. Interestingly, the head rotated in line with the rotation of landscape but not fractal images. That head rotation and gaze direction respond differently to image content suggests that they may be under different control systems. We discuss our findings in relation to current theories on head and eye movement control and how insights from VR might inform more traditional eye-tracking studies.