13 Head Tracking Use Cases for Research
Head tracking is a powerful way to gain insights on behavior. Although this feature is available alongside eye tracking, it remains underutilized and less known. Head tracking is related to eye tracking in the sense that it provides information on attention and orientation. As head tracking provides an additional source of data, it can be used for numerous applications and research settings, including in situations where implementing eye tracking is challenging.
Fundamental to all research that uses head tracking is attention. Since head movement has to do with orientation and attenuation to stimuli, it is a movement that is very closely coupled with attention. A lot of research, in fact, combines head tracking together with eye tracking to assess attention as the two are related.
Head tracking is a more coarse measure for quantifying attention and it is a beneficial measure as it does not require calibration, a big advantage when compared to eye tracking which requires extensive calibration in order to be specific to the participant. Thus, it is a valuable measurement for attention.
Due to its ease of use (not requiring calibration), head tracking works more directly and passively for measuring attention across numerous scenarios, making it easy to track head movement in real time. In an online setting, head tracking is also used to determine whether the participant is facing and attending the screen or somewhere else.
In sports, head movements play various roles. Head movements help players not only navigate through space, but also guide and affect the outcome of their performance. For example, in basketball, head fakes are used in various game situations to deceive the defender, such as if one wants to shoot the ball or pass it another direction. A recent study examined the production costs of using head fakes in basketball and found that reaction time is higher when a pass is performed with a head fake as opposed to without a head fake. Interestingly, this production cost is negated if the player who head fakes has a longer preparation phase (Güldenpenning et al., 2023).
Another example is in baseball when a player goes up to the plate to bat. Gaze and focus on the pitch is crucial, but head movements are also performed during the batting. In fact, evidence from sport psychology studies analyzing baseball behaviors are finding that there is more head rotation occurring than the eye when batting. Thus head movements play a large role in baseball where players are also likely to keep their head down when batting or even turning their head toward the plate, both being behaviors that have been found to be coached (Terry & Fogt, 2023).
Dystonia is an involuntary movement disorder where regular or periodic muscle contractions cause irregular movements and/or postures. A part of this definition includes tremors, including head shake tremors. This is observed in neurological diseases like in Parkinson’s where head nods are done involuntarily. Diagnosing dystonia in general is subjective and not well defined with minimal requirements. For focal dystonia syndromes (which are localized to one body part), there are no diagnostic criteria available. (Albanese, Giovanni, & Lalli, 2018). For patients suffering from head shake tremors, head tracking can be an objective methodology to quantify the movements.
4. Remote Research
There are many technologies that can be used for studying head tracking, but a powerful use case is studying head tracking with a webcam which opens the door to online studies and remote research where participants do not have to constantly come into the lab in order for researchers to gather behavioral measurements. With Labvanced, researchers can activate head tracking on a PC or on a smartphone. This is useful for studying with children where calibration can be difficult for eye tracking but also on studies that rely on smartphones. Since headtracking does not require as much computational power as eye tracking, it performs faster and works on any device whereas eye tracking requires a decent CPU/GPU to work decently remotely.
Real-time feedback look of head movements demonstrating headtracking in Labvanced.
Try out this simple demo of tracking head movements in Labvanced. When you begin the experiment, a facial mesh appears over your face which shows the neural network is working. Then, you can move your head in any direction and see how the sliders move immediately as a result of tracking the head movement in three-dimensional space. On the back end, these sliders are equivalent to data points and coordinates in space. Data about head movements in Labvanced is reported in 6 data streams.
5. Sensory System Feedback and Head Movement
Feedback from sensor systems, like visual and auditory combined with vestibular information, is at the core of the fundamental behavior of motion tracking. Examples include seeing (and also avoiding) a moving car or dodging a buzzing bee. While such a behavior seems simple, it is a complex behavior requiring the coordination of multisensory inputs. Research assessing the combination of head tracking and moving sound is limited even though it's a fundamental behavior that guides how one navigates and understands their surroundings (Leung et al., 2016).
Music is a meaningful expression of sound where movement by those who listen and/or produce it can be naturally elicited. As music is filled with rhythm and powerful musical turns. Whether listening to live music or a recorded version, head movement is bound to take place. A study by Swarbrick et al. in 2019 showed that when participants listen to an album that has yet to be released (thus is unfamiliar) more head movements occur in a live concert as opposed to listening to a recorded, playback version of the concert. Furthermore, those that were familiar with the musician’s previous work also moved more and had more rhythm when compared to neutral-listeners. By tracking head movements, the researchers show how admiration for an artist and listening to live music both influence behaviors like head movement when listening to music.
In the past decade, as technology is improving across all industries, immersive listening systems are becoming more popular and provide a more powerful music listening experience. A recent study looked at musicians’ preferences for playing with classical stereophonic systems versus with a binaural spatialization system (audio that is recorded with a dual microphone setup and creates a 3D audio effect as if it is being heard live). In the experiment, the researchers used headtracking as a behavioral measure and found that the binaural spatialization condition was associated with higher ratings for immersion, social presence, connection with other musicians, localization, and realism and that there were more head movements compared to the classical stereophonic system. These findings suggest that the improved auditory experience led to higher engagement and/or that “the presence of embodied music cognition mechanisms that cause a higher degree of exploration to better understand the action–perception loop” (Tomasetti & Turchet, 2023).
In the context of musical performance, head movements also play a role in communication and signaling between performing musicians. Communication is important for musicians when improvising or where the musical timing is irregular. By using shared attention, performers can signal and interact with other musicians. In a study by Bishop, Cancino-Chacon, & Goebi published in 2019, head movement was measured and the researchers determined that head movement was used as a method to communicate when notes were held. Furthermore, there was a practice/rehearsal effect where musicians showed more movement as a result of increased familiarity with their co-performer. These findings show the importance of coordination and head movements that can serve as a motivation for promoting risk-taking in a creative musical context.
Human Computer Interaction (HCI) focuses on the overlap between design and the use of computer technology. Thus, a major topic in HCI includes the interaction between humans and computers. Most common inputs include mouse and key tracking, however, innovations have made it possible to use head tracking as an input to interact with and command computers.
HCI also plays a crucial role in the study of games. In the intersection between HCI and games, important areas of consideration include: game play interactions and behaviors, as well as the characteristics of players, HCI experts essentially help to design games. As interactions in games can hold several roles, within this category, head nods and movements can hold a significant function in the overall game performance and design. An example of how HCI, gamification, and head movement for control can be found in this game that was developed by Ilves, Gizatdinova, Surakka & Vankka where the player’s goal was to use head movements to guide a character with an additional possibility to use facial expressions. The outcome of the study showed that the players enjoyed this interactive approach and found it to be more entertaining and interesting which suggests that such an approach is worth considering for a more rewarding experience.
8. Assistive Technologies
People with disabilities experience difficulties in interacting and controligous devices like PCs. For this population, assistive technologies serve as a possible solution for increasing independent use and control over devices (Zapala & Balaj, 2012). By using head tracking, assistive technologies can be navigated and controlled via head movements. It is also common to combine these motions with other inputs such as gaze from eye tracking and speech recognition.
Studies that cognition and performance in an aviation setting also employ head tracking metrics. Very often, this is in conjunction with eye tracking in order to assess where one is looking relative to head position. By measuring head movements, researchers can gain insights on cognitive processes like attention, spatial perception, automatic movements, and in the case where a co-pilot is involved, joint attention and situational awareness (Murthy et al., 2020).
10. Automotive Research
When driving, a lot of cognitive processes occur at once. Most importantly, attention to the road and other vehicles drives decision making and spatial awareness. This is evident in situations like lane changing. When changing a lane, the visual behavior preceeds the decision and for this, head movements play an important role when perceiving the space by orienting to the front or side mirrors (Pech, Lindner, & Wanielik, 2014). Such a study is possible to be conducted in Labvanced with remote head tracking using the webcam built in a smartphone that is mounted on the vehicle’s dashboard.
Related to mobility and the environment is street crossing. In this interesting study, Zito et al. used head tracking to assess how young and old pedestrians cross the street. The results found that older people tend to look down at the street (as opposed to the other side) more often than younger pedestrians and that the older pedestrians’ decision making behavior was determined more by the distance of the car, rather than its speed. Such a study shows the importance of head tracking in a commonplace situation.
11. Communication / Body Language
As hinted in the previous section, head movement can be used to communicate via body language. This is a common phenomenon that occurs beyond the context of music and in day-to-day situations. This is evident during conversation where head nods as body language are used to indicate agreement or disagreement. In the next section, we discuss how culture plays a role indicating whether a head shake means ‘no’ or ‘yes’.
Head movements also play a role in sign language. In a study by Puupponen, the relationship between the head and the torso was assessed in Finnish Sign Language. The research paper looked at how narratives of different complexities influence the movement of the head and torso while also generally assessing the role of these two body parts in sign languages in their function as articulators. The general conclusion was that the head movement plays a greater and more active role in Finnish Sign Language and in most cases there was a co-occurrence in the codirection of the movement whereas more complex combinations resulted in differences in the movements. Assessing the role of head movements in sign language is an interesting research use case and can be studied online using Labvanced.
12. Social Psychology
Head movements play an important role in nonverbal communication, however there is a social or cultural aspect to it which determines the meaning of the body language being used like head nods and shakes.
For example, in US culture, moving the head vertically indicates ‘yes’ or a positive response. Whereas in different cultures it can mean ‘no’ or a negative response. Bulgarian culture is an example of this where horizontal movement can indicate ‘no.’ A study by Andonova and Taylor assessed how these cultural differences influence cognitive processes in a situation that is free of communicative intent and found that there is an influence of country for cognitive situations like gestures and culture-specific embodiment patterns.
Eye tracking with infants and children can be challenging because of the lengthy calibration period and requirement to stay still during the calibration stage. Such observations have been found in both clinical and healthy populations and also in studies utilizing eye tracking in fMRI setting (Sasson & Elison, 2012; Son et al., 2020). Headtracking is a powerful solution to this issue as it does not require calibration. Moreover, in this young population, head orientation and attention are highly related (Langton, 2000).
In developmental psychology, headtracking has many use cases, especially in the area of clinical research. An innovative study by Song et al., published in January 2023, established a method for early screening for autism spectrum disorder in children by developing an algorithm that combines head tracking with measured response to the autistic child’s own name. The reason for this combination of variables is because the lack of response to one’s own name is considered as one of the early warning signs of autism spectrum disorder. The researchers showed that using this algorithm which takes into account head position, there is a 93.3% consistency between the method and clinical diagnosis. Such findings pave the way for a new screening test relying on head tracking which is faster and more cost-effective than the current screening protocol which takes a lot of time, expertise and money.
Overall, head tracking is a powerful and useful feature that can be used in various research applications to study cognitive functions like attention, perception, orientation, decision-making, and interactions. Enabling head tracking with a webcam is possible in online research settings and can open new venues of research through remote administration.
- Albanese, A., Di Giovanni, M., & Lalli, S. (2019). Dystonia: diagnosis and management. European journal of neurology, 26(1), 5-17.
- Andonova, E., & Taylor, H. A. (2012). Nodding in dis/agreement: a tale of two cultures. Cognitive processing, 13, 79-82.
- Bishop, L., Cancino-Chacón, C., & Goebl, W. (2019). Moving to communicate, moving to interact: Patterns of body motion in musical duo performance. Music Perception: An Interdisciplinary Journal, 37(1), 1-25.
- Fogt, N., & Terry, J. (2023). Survey of Visual and Predictive Aspects of Batting and Eye Care Utilization in Baseball Players. Journal of Sports and Performance Vision, 5(1), e1-e15.
- Güldenpenning, I., Weigelt, M., Böer, N. T., & Kunde, W. (2023). Producing deceptive actions in sports: The costs of generating head fakes in basketball. Human Movement Science, 87, 103045.
- Ilves, M., Gizatdinova, Y., Surakka, V., & Vankka, E. (2014). Head movement and facial expressions as game input. Entertainment Computing, 5(3), 147-156.
- Langton, S. R. (2000). The mutual influence of gaze and head orientation in the analysis of social attention direction. The Quarterly Journal of Experimental Psychology: Section A, 53(3), 825-845.
- Leung, J., Wei, V., Burgess, M., & Carlile, S. (2016). Head tracking of auditory, visual, and audio-visual targets. Frontiers in neuroscience, 9, 493.
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- Pech, T., Lindner, P., & Wanielik, G. (2014, October). Head tracking based glance area estimation for driver behaviour modelling during lane change execution. In 17th International IEEE Conference on Intelligent Transportation Systems (ITSC) (pp. 655-660). IEEE.
- Puupponen, A. (2018). The relationship between movements and positions of the head and the torso in Finnish Sign Language. Sign Language Studies, 18(2), 175-214.
- Sasson, N. J., & Elison, J. T. (2012). Eye tracking young children with autism. JoVE (Journal of Visualized Experiments), (61), e3675.
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- Song, C., Wang, S., Chen, M., Li, H., Jia, F., & Zhao, Y. (2023). A multimodal discrimination method for the response to name behavior of autistic children based on human pose tracking and head pose estimation. Displays, 76, 102360.
- Swarbrick, D., Bosnyak, D., Livingstone, S. R., Bansal, J., Marsh-Rollo, S., Woolhouse, M. H., & Trainor, L. J. (2019). How live music moves us: head movement differences in audiences to live versus recorded music. Frontiers in psychology, 9, 2682.
- Tomasetti, M., & Turchet, L. (2023). Playing With Others Using Headphones: Musicians Prefer Binaural Audio With Head Tracking Over Stereo. IEEE Transactions on Human-Machine Systems.
- Zapała, D., & Bałaj, B. (2012). Eye Tracking and Head Tracking–The two approaches in assistive technologies. In book: Sborn'ik pvr'ispvevkuu z mezinárodn'i vvedecké konference (pp.2406-2415).
- Zito, G. A., Cazzoli, D., Scheffler, L., Jäger, M., Müri, R. M., Mosimann, U. P., ... & Nef, T. (2015). Street crossing behavior in younger and older pedestrians: an eye-and head-tracking study. BMC geriatrics, 15(1), 1-10.