New study shows that risk of veering off topic in conversation increases with age

Research led by Paul Hoffman (School of Philosophy, Psychology and Language Sciences) has found that people are more likely to deviate off topic during conversation the older they become.

A series of computerised tests were used to assess speech samples from a group of 60 people whose ages ranged from 18 to more than 80 years old. These tests found that those who were older were less skilled than younger people at keeping a conversation on track. 

Two tests were implemented, one to measure the ability to choose relevant information and another to quantify knowledge. 

Firstly participants were given a series of subjects to speak about for one minute. Researchers then measured the coherence of the participants’ speech – how likely they were to talk about the subject given, rather than producing irrelevant information. Then they were given a series of tests to measure thinking skills. One of these measured how knowledgeable they were, by testing their vocabulary. Another tested their ability to focus on specific aspects of their knowledge – for example, by matching familiar objects based on their colour.

The team found, on average, older people were not as skilled as younger people at selecting which information to share. People with less coherent speech tended to have more knowledge but were less good at selecting the most relevant elements of their knowledge.

This study may help in our understanding of underlying cognitive mechanisms that can cause changes in the quality of social interactions as people age. 

Paul Hoffman said: “Previous studies had found that older people tend to be less coherent in conversation but the reason for this change wasn’t clear. 

“Here we found older people are more knowledgeable than young people but are less skilled at selecting which aspects of their knowledge are most important. We all get distracted by irrelevant thoughts from time to time when we’re speaking, but our results suggest that this happens more often as we get older and accumulate more knowledge.”