Can painkillers reduce your awareness of errors?

Paracetamol, also known as acetaminophen, and most popularly marketed as “Panadol” in Australia, is a widely used painkiller. It has been a widely used painkiller since the 1950s which makes it remarkable that it is only in recent years that we feel we have a handle on how it works, and even then we aren’t totally sure. Still, paracetamol works and it is relatively safe at the prescribed dosage unless you have a compromised liver or, according to a new study, you don’t want to miss errors.

Those who took paracetamol showed a much smaller Pe when making an error which suggests that the drug is reducing awareness of making the error.

The study involved subjects participating in an error detection called the Go or No Go Test. In the test subjects were asked to hit a Go button every time the letter “F” flashed on the screen but refrain from hitting the button if an “E” flashed on the screen. You have to be moving very quickly to catch all the Fs and miss the Es.

Every subject was hooked up to an EEG to measure electrical activity in the brain. These EEGs were used to look for brain wave patterns called Error Related Negativity (ERN) and Error Related Positivity (Pe). What usually shows up on an EEG is that when someone makes an error there is a large increase in ERN and in Pe.

In the study one group was given 1000mg of paracetamol (the standard dose) prior to doing the test while the other group did not take paracetamol. Those who took paracetamol showed a much smaller Pe when making an error which suggests that the drug is reducing awareness of making the error.

The researchers say that reduced ability to recognise an error may translate into problems for cognitive function in daily life. The task in this study employed mostly Go situations so when you see an E it requires cognitive control to not press Go. An additional and unexplained finding is that those given paracetamol missed more of the Go stimuli than the other group. The researchers theorise, without being definitive, if paracetamol causes people to become distracted and the mind to wander.

Perhaps a couple of paracetamol before your next exam or major work meeting might not be the best idea after all.