Olivia Newton’s Physical is a great song (so is the video!). This 1980’s classic candidly describes the experience of sexual desire without leaving out the feelings of reduced self-control that sometimes come with it (“It’s gettin’ hard this holdin’ back / If you know what I mean” [music intensifies]).

Sexual arousal has been associated with

• positive emotions and can support interpersonal attachment and well-functioning long-term relationships
• negative emotions, and hence it can be conceived as an ambivalent affective experience

Sexual arousal also affects psychological processes such as attention, working memory, motivation, and decision-making. Changes in any of these, or combination, may lead people to be more willing to engage in risky activities and relax their morals (at least in hypothetical scenarios).

Considering arousal’s impacts on emotional states and cognition, Anna Render and Petra Jansen (pictured below) hypothesized that it might also affect people’s sense of agency over behavior. They presented the results in their recent article published in the Psychonomic Society journal Attention, Perception & Psychophysics.

Physical time, psychological time, and agency

But how does one measure the subjective experience of agency? And how and why should sexual arousal influence agency? Render and Jansen took advantage of an implicit approach to measure it called intentional binding. Intentional binding relies on comparing the physical time between events with the psychological representation of time. This might sound complex, but when it comes to time perception, all you need to do is to compare objective time measures with subjective estimates of time.

Let’s get physical: Imagine you have two clocks, like the one above, but running very fast. At the same time, a person and a machine press a button, and a few milliseconds later, each clock beeps. Of course, the time between the button presses and the beeps in each clock are the same. Simple and intuitive.

Let’s get psychological: Imagine again that you have two running clocks. At the same time, a person and a machine press a button, and a few milliseconds later, each clock beeps. The times between the button presses and clock beeps are objectively the same. But if you ask the person that pressed the button to estimate the time between the time press and the beep, they are likely to estimate a shorter interval. Less intuitive, right?

The subjective compression of the time elapsed between a voluntarily controlled behavior and a following event resulting from that behavior is called intentional binding and constitutes an implicit measure of the sense of agency. Note that such a time-shrinking can happen in two ways:

1. if the action subjectively drifts towards the event – called action binding, or
2. if the event subjectively drifts towards the action – called outcome binding.

Considering the effects of sexual arousal on cognitive processes, its ambivalent effects on affective experience, and some of its similarities with other affective states, the authors hypothesized that sexual arousal should decrease intentional binding, reflecting an implicit reduction of agency. And more specifically, they expected that the effects would be restricted to action binding (as opposed to outcome binding) because participants were in full, voluntary control of the actions and controlled (a critical determinant of observing action binding effects).

Let me see your body behavior talk

To test these hypotheses, the authors compared the behavior of people exposed to an erotic scene from the 2015 movie “Love” (worth checking out for, umm, … science) or to an emotionally neutral scene from a documentary. All participants took part in the Libet clock task.

The Libet clock task presents an accelerated clock (in the experiment, it completed a cycle approximately every 2.5 seconds). It requires participants to engage in a series of button presses with or without a consequence (i.e., a tone 250 ms after the button press). In different trials, participants must estimate the time they pressed the key or the time the tone was presented using the accelerated clock as a reference. This procedure allows obtaining separate measures of action and outcome binding. Participants completed it twice: before and after getting watching the video. A visual summary is shown in the figure below.

To determine the effect of the sexual or neutral video on participants’ affective experience, the authors measured participants’ valence (how positive or negative is their affective experience) and arousal (the subjective level of physiological activation experienced) before and after the video using the Self-Assessment Manikin (assesses affective reactions).

As you may expect, the neutral scene produced no changes in the affective experience of participants. The erotic video, in contrast, increased participants’ arousal but did not change valence (possibly because of the ambivalent effects of sexual arousal on affective experiences, as described above).

What about intentional binding? There was no evidence for the effect of the erotic film on intentional binding. However, taking into account individual differences in the degree of change between arousal levels before and after the video (i.e., including the difference between pre- of post-film arousal scores as a covariate, and correlating these changes with the intentional binding measures obtained before and after the film), higher arousal increases led to decreases in action binding (whereas the outcome binding remained intact). This finding suggests that the arousal increases produced by the erotic scene reduced participants’ sense of agency.

What it means, what it doesn’t, and where to go from here

In the words of Render and Jansen,

The results of the current study support the notion that general arousal, but not sexual arousal specifically, impairs action binding.

Additionally, their work offers methodological insights and has implications for applied contexts.

The results suggest that the film’s affective experience impacted intentional binding, specifically in its action binding component, without impacting outcome binding. Other studies have not made such a distinction. And yet other studies, using different experimental paradigms, have reported arousal-related increases of intentional binding. The authors also highlighted the importance of controlling for individual differences when studying this topic. Both factors suggest that subtle methodological differences are essential, and there is a need for more research.

From a more applied point of view, the decreased sense of agency suggested by results has important implications for the study of violent behavior, much as previously discussed in the context of other emotions, such as anger and fear. In the words of the authors:

If action binding is affected by general arousal, this could be relevant for models explaining violent behavior, as general arousal may be an important factor in sexual and general violent behavior.

As intriguing as this last possibility is, I’m sure that Olivia Newton didn’t have this idea in mind when singing the lines, “You gotta know that you’re bringin’ out / The animal in me!”

Psychonomic Society’s article focused on in this post:

Render, A., & Jansen, P. (2020). Influence of arousal on intentional binding: Impaired action binding, intact outcome binding. Attention Perception Psychophysics. https://doi.org/10.3758/s13414-020-02105-z