I can see three potentially important differences between your methods and those of the original study you linked that found such strong results.
One is duration. They say their session were 2.5 hours each. Yours tended to be 5-30 minutes at a time. I can imagine a few mechanisms that might make this impact the results:
Perhaps you can compensate for elevated CO2 for short periods of time by unconsciously taking larger breaths
Perhaps physiological CO2 doesn’t change that quickly in response to atmospheric CO2. Perhaps if you only spent a short time in high-CO2 rooms, it didn’t have a chance to drop your physiological CO2 to a level that makes a difference
Perhaps physiological CO2 only affects cognition over longer time intervals for reasons unrelated to sheer physiological CO2 levels, perhaps for psychological reasons
The other is CO2 levels. Here’s a screenshot of a histogram of your CO2 levels:
You have a fair number of data points in the original study’s low-medium range. But their median “high” range was 2,496 ppm, and you barely have any data in that range.
Finally, their task was multifaceted, whereas yours was very narrow. Here’s the table of their decision-making measures and scores:
Notice that focused activity improved with elevated CO2, and information search was roughly unaltered. I don’t want to make an argument about which variables your word game maps onto most neatly, but it seems possible that you might have gotten different results with a more robust measure.
Add in questions about the precision of your air monitor (which does, I hasten to add, seem to cluster by time nicely in the way you’d expect if it were at least somewhat accurate), confounding factors—maybe you chose to stop playing when you felt yourself doing poorly, for example—and the lack of blinding in your study, and I’m just not ready to trust your results over theirs.
That’s not to say you should necessarily trust theirs, though! I just think that if I’d run your experiment on myself, I would probably not put very much weight in the evidence. Instead, I would focus more on integrating additional evidence from the published literature, and update whatever prior that established a little bit to account for these results.
I can see three potentially important differences between your methods and those of the original study you linked that found such strong results.
One is duration. They say their session were 2.5 hours each. Yours tended to be 5-30 minutes at a time. I can imagine a few mechanisms that might make this impact the results:
Perhaps you can compensate for elevated CO2 for short periods of time by unconsciously taking larger breaths
Perhaps physiological CO2 doesn’t change that quickly in response to atmospheric CO2. Perhaps if you only spent a short time in high-CO2 rooms, it didn’t have a chance to drop your physiological CO2 to a level that makes a difference
Perhaps physiological CO2 only affects cognition over longer time intervals for reasons unrelated to sheer physiological CO2 levels, perhaps for psychological reasons
The other is CO2 levels. Here’s a screenshot of a histogram of your CO2 levels:
You have a fair number of data points in the original study’s low-medium range. But their median “high” range was 2,496 ppm, and you barely have any data in that range.
Finally, their task was multifaceted, whereas yours was very narrow. Here’s the table of their decision-making measures and scores:
Notice that focused activity improved with elevated CO2, and information search was roughly unaltered. I don’t want to make an argument about which variables your word game maps onto most neatly, but it seems possible that you might have gotten different results with a more robust measure.
Add in questions about the precision of your air monitor (which does, I hasten to add, seem to cluster by time nicely in the way you’d expect if it were at least somewhat accurate), confounding factors—maybe you chose to stop playing when you felt yourself doing poorly, for example—and the lack of blinding in your study, and I’m just not ready to trust your results over theirs.
That’s not to say you should necessarily trust theirs, though! I just think that if I’d run your experiment on myself, I would probably not put very much weight in the evidence. Instead, I would focus more on integrating additional evidence from the published literature, and update whatever prior that established a little bit to account for these results.