Using Heart Rate Variability to Analyze Stress in Conversation

Hi, my name’s Paul LaFontaine and I’m the organizer of the Denver Quantified Self meet up.

Okay, have you ever actually had a session with your boss and she asked you a question and you just can’t remember for the life of you what the answer is, and you know the information?

I call that vapor lock, and I experienced it, and we all experienced it. And it’s really uncomfortable when it happens at work. And I thought vapor lock came from a relatively important person asking a difficult question, which made for a difficult conversation.

Like the boss talking about my performance, or a negotiation over the points that were really hard to negotiate. And I wanted to actually reduce the time I was in vapor lock so that I could become a kind of negotiation ninja, that I could stay out of vapor lock and project it on others and come up with great results in my negotiation.

So I wanted to understand vapor lock, and when it happened. So, what I did was I measured my heart rate variability, while in meetings at work because I knew that work would provide me with a tremendous number of environments, which I could test and compare different types of meetings. And heart rate variability is an excellent measure because each of our hearts varies based on how our nervous systems are reacting to the environment around us specifically to threats.

So, if there are no threats in the environment, you're relaxed, and your heart actually varies quite a bit right. It goes up and down, and that means that your blood is actually moving to your brain and you can think.

When you perceive that there are threats, the blood goes to your hands and to your legs because you’re ready to run. Your heart beats at a very steady pace, you’ll variability goes down, and you deliberately lose your brain in that instant.

So I had a great platform that I could actually look at different environments of who I was talking to, what I was talking about, and I could use heart rate variability to tell whether my brain was actually engaged.

How I did it, was I used off the shelf technology. When I would go into a meeting I would press a button, and it would measure my heart rate variability, and in the meeting, I would press to stop it. I'd upload it to Excel, so I had a nice dataset.

I added to it the difficulty of the conversation, so I would give it a scale of 1 to 5 in how difficult it was. And you see on the screen, 156 conversations that I actually measured over an eight month period, using a Polar heart rate belt H7, it had the Sweetwater app, and the heart rate variability logger app from Marco Altini .

The way I measured the propensity to vapor lock, was 10 successive intervals at under 17 milliseconds. At a relaxed state or an excited state, I’d generally go from 1000 milliseconds per interval to 500, so 17 milliseconds which is really tight. So that was pretty sure that my heart was often running.

And the result was that I get a map from the meeting that would look like this. It would give me the average amount of time I was in vapor lock, but also the time period, so that I could look at what we were talking about at the time that triggered the vapor lock for me.

So what did I learn? I learned that my hypothesis about difficult conversations was completely wrong. A difficult conversation does not actually trigger vapor lock in me. I also learned that I am actually not a very good ninja trainee. So what you see here is my over time, and with a lot of effort for me trying to get better and the red line is flat. The red line is the average time in vapor lock it didn’t go down at all. So I’m not a very good ninja trainee at all, despite the time in the dojo.

Here on the next slide, you going to see the difficulty of the conversation by less difficult to more difficult, and you can see that the coefficient at the bottom is 0.17, no relationship to the difficulty of the conversation. And when I was in vapor lock, which of course begs the question, what was going on. How can we actually anticipate it? Much to my surprise, it was the number of people in the room.

So if I was in the room with a large number of people, four or above I tend to be in vapor lock more. If I was in a one-to-one conversation, I would very rarely, regardless of how difficult the topic was.

Here you see the numbers, and you can see how it just almost winds up perfectly, the 85 on the bottom is actually a Quantify Self meet up speech, which is a very friendly audience, and I knew the material very well, r equals 0.73, a very strong relationship.

So that leads to a new ninja strategy, right on the strategy is really simple. Look at the number of invites in the meeting, if it’s going to be a larger number stick to your points. If somebody ask you a question, say let’s take it off-line. If it’s a one on one, you can actually explore a little bit more because the stress level is going to be low and your brain is going to be engaged.

So my conclusion is I cannot avoid nor train for vapor lock, I can only actually plan for it. And my next study is actually to look at vapor lock over time of day, because our body actually loses momentum over the course of the day, and can I move my one on ones up front to make myself more effective over all.

Here’s my Twitter, my blog, and my online moniker is QuantSelfLaFont. I really enjoyed this study and enjoyed talking to you today, and now I’ll take your questions. Thanks.