Common painkiller making us overlook mistakes

You may want to rethink popping that pill for pain as a new study has suggested that a popular over-the-counter painkiller may hinder the brain's error-detection process.

The University of Toronto research, authored by a team including postdoctoral fellow Dan Randles and researchers from the University of British Columbia, is the first neurological study to look at how the painkiller acetaminophen (Tylenol) could be inhibiting the brain response associated with making errors.

"The core idea of our study is that we don't fully understand how acetaminophen affects the brain," says Randles. "While there's been recent behavioural research on the effects of acetaminophen, we wanted to have a sense of what's happening neurologically."

To test the idea two groups of 30 were given a target-detection task called the Go or No Go. Participants were asked to hit a Go button every time the letter F flashed on a screen but refrain from hitting the button if an E flashed on the screen. "The trick is you're supposed to move very quickly capturing all the GOs, but hold back when you see a No Go," says Randles.

"It looks like acetaminophen makes it harder to recognize an error, which may have implications for cognitive control in daily life," says Randles.

"An obvious question is if people aren't detecting these errors, are they also making errors more often when taking acetaminophen? This is the first study to address this question, so we need more work and ideally with tasks more closely related to normal daily behaviour."

The research is published in the journal Social Cognitive and Affective Neuroscience.