Peripheral-physiological and neural correlates of the flow experience while playing video games: a comprehensive review

Using caffeine as a chemical means to induce flow states

Flow is an intrinsically rewarding state characterised by positive affect and total task absorption. Because cognitive and physical performance are optimal in flow, chemical means to facilitate this state are appealing. Caffeine, a non-selective adenosine receptor antagonist, has been emphasized as a potential flow-inducer. Thus, we review the psychological and biological effects of caffeine that, conceptually, enhance flow. Caffeine may facilitate flow through various effects, including: i) upregulation of dopamine D1/D2 receptor affinity in reward-associated brain areas, leading to greater energetic arousal and 'wanting'; ii) protection of dopaminergic neurons; iii) increases in norepinephrine release and alertness, which offset sleep-deprivation and hypoarousal; iv) heightening of parasympathetic high frequency heart rate variability, resulting in improved cortical stress appraisal, v) modification of striatal endocannabinoid-CB1 receptor-signalling, leading to enhanced stress tolerance; and vi) changes in brain network activity in favour of executive function and flow. We also discuss the application of caffeine to treat attention deficit hyperactivity disorder and caveats. We hope to inspire studies assessing the use of caffeine to induce flow.

The effect of music tempo on movement flow

There has been much controversy over the effects of music tempo on movement flow. In this study, a single-factor repeated-measurement design was used to explore the effect of music tempo (fast, slow, and no music control) on movement flow by measuring both subjective experiences and objective electroencephalographic (EEG) characteristics during brisk walking. In the experiment, 20 college students walked briskly on a treadmill using EEG equipment. Each participant walked for 10 min on three different days. Their brain waves were recorded during brisk walking on a treadmill. After each walk, the participants completed a form of short flow state scale-2 (S FSS-2), which covered nine major aspects of flow. The results showed that music tempo had a significant effect on subjective experiences and objective physiological characteristics; that is, a higher subjective flow level for fast-tempo music in brisk walking and a significant enhancement of mean power values in the subconscious brain waves of the delta, theta, alpha, and beta bands for fast tempo music were observed. A fast tempo facilitated the movement flow. The findings of this study can be instructive for the use of music in exercises to improve sports training outcomes.

Presence in video games: A systematic review and meta-analysis of the effects of game design choices

Sense of presence is a widely assessed dimension of video game player experience. A systematic literature review and a meta-analysis were conducted to provide a more comprehensive view of the elements of game design that have an effect on the sense of presence, as well as its different dimensions studied and assessment techniques. The review revealed that many major categories of game design aspects were well represented. The meta-analysis revealed that several game design factors have significant effects on different dimensions of presence. The largest revealed effects were that playing games with a head-mounted display and motion controller rather than a monitor display and non-motion controller has a large effect on global presence. Also, playing with human co-players rather than computer-controlled co-players and playing cooperatively rather than competitively have a very large and large effect on social presence, respectively. Implications for future research are discussed, such as investigating the effects of design factors on presence in a more targeted manner, systematically assessing presence with its most relevant sub-dimensions, and using more similar rating scales. Design recommendations, with their expected impact on players' sense of presence, are proposed.

Group‐based flow: The influence of cardiovascular synchronization and identifiability

Previous work has demonstrated the role of group-based flow in group performance and experience, but the physiological correlates of these relations are largely unknown. We examined the relation between cardiovascular synchronization, self-reported flow, and performance in a three-person online gaming task. We included measures of Heart Rate (HR), Pre-Ejection Period (PEP), and Cardiac Output (CO) as indices of task engagement and challenge (vs. threat) motivation. Group members were identifiable (i.e., visible) or anonymous during the game. Results indicated that PEP (as a marker of task engagement) and within-group synchronization in PEP, predicted flow, and that synchronization in PEP mediated the relation between group performance and experienced flow. The anonymity vs. identifiability of group members did not play a role in these effects. Results are discussed in terms of implications for flow theory, group dynamics, and physiological synchrony.

First few seconds for flow: A comprehensive proposal of the neurobiology and neurodynamics of state onset

Flow is a cognitive state that manifests when there is complete attentional absorption while performing a task. Flow occurs when certain internal as well as external conditions are present, including intense concentration, a sense of control, feedback, and a balance between the challenge of the task and the relevant skillset. Phenomenologically, flow is accompanied by a loss of self-consciousness, seamless integration of action and awareness, and acute changes in time perception. Research has begun to uncover some of the neurophysiological correlates of flow, as well as some of the state's neuromodulatory processes. We comprehensively review this work and consider the neurodynamics of the onset of the state, considering large-scale brain networks, as well as dopaminergic, noradrenergic, and endocannabinoid systems. To accomplish this, we outline an evidence-based hypothetical situation, and consider the flow state in a broader context including other profound alterations in consciousness, such as the psychedelic state and the state of traumatic stress that can induce PTSD. We present a broad theoretical framework which may motivate future testable hypotheses.

The Effect of Heart Rate Variability Biofeedback Training on Vagal Tone in Athletically Talented Secondary School Students

This study examines whether twelve sessions of heart rate variability biofeedback training would improve vagally mediated heart rate variability. If so, it would go some way in explaining why breathing-based interventions reduce clinical symptoms and improve non-clinical performance outcomes. Methods: Thirty participants (N = 30, Nfemale = 13) aged 14–13-year-old, all talented athletes, from a sport specialist school in SE London UK, were randomly divided into three groups, a control group, a psychology skills training combined with heart rate variability biofeedback training group, and a heart rate variability biofeedback only group. For the combined group, a variety of typical psychological skill training techniques were also used. Results: Paired participant t-test and the Wilcoxon Signed Rank test found non-significant differences between pre- and post-intervention measurements of heart rate variability. Non-significant results remained even after pooling the biofeedback training groups (n = 19). Conclusions: Our results do not indicate that beneficial effects associated with focused breathing training can be attributed to improved vagal tone. Further investigation into the underlying mechanisms of the benefits of focused breathing techniques is necessary to maximize clinical and non-clinical outcomes.

The psychophysiological mechanisms of real-world time experience

Our sense of time is fallible, often resulting in the sensation of time flying by quickly or dragging slowly. It has been suggested that changes in sympathetic (SNS) and parasympathetic nervous system (PNS) activity may influence the perceived passage of time, however this proposition has never been tested during real-world temporal experience. The current study directly tested the relationship between the passage of time and SNS–PNS activity in the real-world. Sixty-seven participants completed a normal day’s activities whilst wearing sensors to capture electrocardiography (ECG), electrodermal activity (EDA) and movement. They also provided hourly rating of the subjective speed at which time was passing. Results revealed that greater SNS activity (e.g., increased heart rate, frequency of phasic skin conductance response) was associated with time passing more quickly. PNS activity was not related to time experience. Whilst the findings support previous suggestions that changes in physiological arousal are associated with distortions to the passage of time, the effects are small and other factors are likely to contribute to real-world temporal experience.

Inter-brain synchronization occurs without physical co-presence during cooperative online gaming

Inter-brain synchronization during social interaction has been linked with several positive phenomena, including closeness, cooperation, prosociality, and team performance. However, the temporal dynamics of inter-brain synchronization during collaboration are not yet fully understood. Furthermore, with collaboration increasingly happening online, the dependence of inter-brain phase synchronization of oscillatory activity on physical presence is an important but understudied question. In this study, physically isolated participants performed a collaborative coordination task in the form of a cooperative multiplayer game. We measured EEG from 42 subjects working together as pairs in the task. During the measurement, the only interaction between the participants happened through on-screen movement of a racing car, controlled by button presses of both participants working with distinct roles, either controlling the speed or the direction of the car. Pairs working together in the task were found to have elevated neural coupling in the alpha, beta, and gamma frequency bands, compared to performance matched false pairs. Higher gamma synchrony was associated with better momentary performance within dyads and higher alpha synchrony was associated with better mean performance across dyads. These results are in line with previous findings of increased inter-brain synchrony during interaction, and show that phase synchronization of oscillatory activity occurs during online real-time joint coordination without any physical co-presence or video and audio connection. Synchrony decreased during a playing session, but was found to be higher during the second session compared to the first. The novel paradigm, developed for the measurement of real-time collaborative performance, demonstrates that changes in inter-brain EEG phase synchrony can be observed continuously during interaction.

Brain–Heart Interaction and the Experience of Flow While Playing a Video Game

The flow state – an experience of complete absorption in an activity – is linked with less self-referential processing and increased arousal. We used the heart-evoked potential (HEP), an index representing brain–heart interaction, as well as indices of peripheral physiology to assess the state of flow in individuals playing a video game. 22 gamers and 21 non-gamers played the video game Thumper for 25 min while their brain and cardiorespiratory signals were simultaneously recorded. The more participants were absorbed in the game, the less they thought about time and the faster time passed subjectively. On the cortical level, the fronto-central HEP amplitude was significantly lower while playing the game compared to resting states before and after the game, reflecting less self-referential processing while playing. This HEP effect corresponded with lower activity during gameplay in brain regions contributing to interoceptive processing. The HEP amplitude predicted the level of absorption in the game. While the HEP amplitude was overall lower during the gaming session than during the resting states, within the gaming session the amplitude of HEP was positively associated with absorption. Since higher absorption was related to higher performance in the game, the higher HEP in more absorbed individuals reflects more efficient brain–heart interaction, which is necessary for efficient game play. On the physiological level, a higher level of flow was associated with increased overall sympathetic activity and less inhibited parasympathetic activity toward the end of the game. These results are building blocks for future neurophysiological assessments of flow.