Edson Severnini

The level of particulate matter in the air today is above the recommended World Health Organization guidelines.

I always go for my morning walk and I always check on my phone what is the air quality index for the day.

If it's below 50, you are in a good or green color of the AQI.

If it's between 50 and 100, it's yellow, like the moderate pollution.

And then above 100 is when I avoid leaving the house because that's where it starts getting a little bit unhealthy to be outside.

Pollution levels are not measured around us, like attached to our bodies.

So that would be the ideal experiment.

You are breathing the air, you know exactly how much pollution you have in that air.

It's not the case.

And so that creates noise in the data, which would underestimate the relationship between cognitive function and pollution.

We used the wind direction that brings pollution from other locations, and that makes a uniform level of pollution for all individuals in an area, independently on whether they are close or slightly farther away from the monitor.

I'm not a medical expert.

What I'm going to say now is based on, you know, reviews of this literature.

That, again, is Boston College economist Edson Severnini.

There are two ways where air pollution could impair cognition.

One is that they go directly to the brain and then it affects the functioning of the neurons.

But also they stimulate pro-inflammatory, I think it's called cytokines.

And so this is a more indirect route.

But everybody who is doing research on this topic, they always see processes that are affected by pollution, oxidative stress, inflammation, some neuron loss.

So if you were playing on a day that was above the threshold that we set and you were performing like in the 75th percentile, on average, you would have been on the 80th percentile that day.