Adam Grant, the superstar psychologist and regular New York Times contributor who has a tendency to overstate and oversimplify scientific findings, tweeted this the other day:
The best place to relax is near water. After just 2 minutes of viewing water outdoors, blood pressure and heart rate drop. It’s more calming to look at a lake, pool, or stream than trees or grass. Beaches are popular for a reason. Wider bodies of water bring more tranquility.
He linked to a Journal of Environmental Psychology study published in 2022 called “Transient decreases in blood pressure and heart rate with increased subjective level of relaxation while viewing water compared with adjacent ground.” The authors are Richard G. Coss and Craig M. Keller.
Anyone familiar with psychology’s recent replication travails, particularly when it comes to anything related to social priming (the idea that brief cues can significantly alter people’s judgements and/or behavior), should be skeptical of a study like this. Sure enough, there are all sorts of red flags, both in the study itself and in Grant’s summary of it.
Before we even get to them, though, I found the animating theory of this paper weird. The authors note that since we as a species require water to survive, we might have a deep evolutionary and psychological link to it. It makes sense, then, that seeing it might relax us. Okay, but about 97% of the earth’s water is salty, and given the hundreds of thousands of miles of coastline on the planet, surely “seeing water” is tightly correlated with “seeing saltwater,” which throws this whole thing into question? And even if researchers did prove that perceiving water led to a relaxation response, wouldn’t they have to either prove that this effect didn’t occur on ocean beaches (which seems unlikely), or explain how it could apply to both situations?
ANYWAY, the first study in the paper consisted of “Thirty two individuals (16 men and 16 women) who were members of the Davis Aquatic Masters swim team [and who] volunteered to participate. Three age classes were selected for study, consisting of 6 men and 4 women between 18 and 30 years of age, 4 men and 6 women between 31 and 50 years of age, and 7 men and 5 women between 50 and 85 years of age.”
Each participant was taken, in random order, to three sites, pictured here:
More on the methods:
Participants were instructed to read and sign permission forms before proceeding to the three locations where they were instructed to stand still without speaking and hold his/her wrist cuff on the left arm at heart level. Once the participant was positioned for blood-pressure sampling, the participant was instructed to visually fixate a specific target for 1 min, following which the blood-pressure monitor was immediately activated by the researcher (CK) standing nearby. No other individuals were nearby during this sampling period. While the participant maintained visual fixation, blood-pressure measurement started 15 s later during the ∼25-sec period of cuff deflation. This device was then removed from the participant before moving to next sampling site. The three sampling sites were visited successively in a preselected randomized order. At the swimming pool, participants stood approximately 2 m from the edge of the water and fixated a spot on the water’s surface for a 1 min 40 s following which they walked to the next sampling site. At the parking lot, participants were instructed to fixate a tree at approximately 18-m distance for 1-min 40 s. At Russell Blvd., participants standing on the sidewalk were instructed to fixate for 1 min 40 s a triangular sign diagonal to the street at 105-m distance. Following completions of these tasks, the blood-pressure monitor was removed and the systolic, diastolic and heart (pulse) rates of participants were recorded from the device’s memory. To measure any acoustical distractions, the background sound-pressure level (SPL) at each site was measured using the A setting on the sound-pressure meter (Radio Shack Model 33-20-50). ([sic] throughout)
All of which yielded the following chart (for both measures, lower is better, health-wise):
Summing things up, the authors write:
The results of Study 1 showed that after visually fixating the water in the swimming pool for 1 min 40 s, the [systolic]/[diastolic] ratio for blood pressure was reliably lower compared with focusing on a tree in the parking lot and a small distant sign on Russell Blvd. Heart rate was also reliably lower while viewing water than after viewing the sign on Russell Blvd. Thus, the results of our study provide full support to our hypothesis that viewing water can decrease blood pressure compared with viewing selected urban-habitat features without water. For heart rate, however, our hypothesis received only partial support due to the lack of a reliable difference between viewing water and the tree in the parking lot.
Does it provide “full support” for that hypothesis? I don’t think so. Who is to say that it was the water causing these differences, rather than the fact that the indoor pool setting was calmer and quieter than the outdoor urban ones? Plus, these were members of a swim team! Surely they had positive associations with pools that could be influencing their physiological readings, no? If your claim is that viewing aquatic scenes has a general impact on human well-being, why would you choose swimmers rather than random people?
In the second study, the authors took a sample of 73 participants from “the University of California, Davis campus and city community.” They were taken to six different outdoor sites and administered tests of their blood pressure and heart rate while looking both at water and adjacent ground. They were also asked to rate their subjective level of relaxation.
Here are the results for that one:
So in most cases, there were no statistically significant differences. In other cases, there were. For example, the researchers’ statistical tests “showed that viewing the small lake at site 1. . . lowered heart rate significantly compared with viewing the grassy hill[.]” Okay.
After running the statistical tests that were part of their overall hypotheses, the researchers also did some exploratory analysis, including a test of whether wider bodies of water were more relaxing. They found that if they averaged the relaxation scores for the wider sections of the creek used in this study, versus the narrower sections, doing so yielded a “highly significant” result.
Okay!
***
Psychology researchers shouldn’t run studies like this anymore, and journalists shouldn’t publish them. This study doesn’t tell us anything. The researchers threw a bunch of stuff at a wall to see what stuck, and then some stuff stuck, and the researchers said “Look at what stuck!” In all likelihood, they ran a bunch of other exploratory statistical tests, didn’t get anything, and simply didn’t report their results.
And then a very famous psychologist summarized all this as
The best place to relax is near water. After just 2 minutes of viewing water outdoors, blood pressure and heart rate drop. It’s more calming to look at a lake, pool, or stream than trees or grass. Beaches are popular for a reason. Wider bodies of water bring more tranquility.
We should really be past this by now! Even if these results are robust — and I would bet real, actual money against a robust replication — they don’t necessarily tell us anything meaningful about human life in real-world situations. The authors do note the artificial nature of their experiment at the end of the paper, but propose that maybe all those glimpses at water could have a cumulative effect during a walk.
I think a much better theory is that social priming research has been more or less debunked and that researchers should spend their limited resources on other, more promising kinds of work. At bare minimum, if you do insist on publishing a study like this, it should have guardrails in place, foremost among them preregistration, to forestall charges of cherry-picking and more general methodological uselessness.
Anyway, I found this annoying. I’m going to go seek out some water to chill out a bit.
Questions? Comments? Favorite totally true social priming results? I’m at [email protected] or on Twitter at @jessesingal. I took the photo, which is of Alcatraz. I wonder if inmates there felt relaxed as they looked out at the Bay?