The dual-task study assessed the effects of cell phone conversations on performance in a simulated driving task. The key finding was that unconstrained conversation using a handheld or hands-free cell phone doubled the failure rate of detecting simulated traffic signals and slowed reactions to detected signals. The researchers believe this was because cell phone use disrupts driving performance by diverting attention to an engaging cognitive context other than the one immediately associated with driving.
A question to consider is what motivated the researchers to conduct this study.
In 2001 cell phone ownership boomed, with 116 million cell phones users in the United States. This increase in ownership led to an increase in people talking on their phones while driving. A study from 1999 indicated 85% of cell-phone owners’ used their phone ‘at least occasionally’ while driving and 27% reported using their phones on half their trips. Due to the risks associated with cell phone use while driving there have been legislative efforts world wide to restrict cell phone use on the road. Largely the legislation assumes that any interference is due to peripheral factors such as dialling and holding the phone while talking. This study explores this belief as it is important to consider whether the assumption that interference is due to peripheral factors is correct.
Now we are going to review some literature associated with our study. One source that linked cell phone use and road accidents was a study where phone records of individuals in road accidents were evaluated. It was found that 24% of these individuals were using their cell phone prior to the accident. The authors of this study claimed that cell phone use led to a fourfold increase in the likelihood of getting into an accident- and that there were no safety advantages to using a hands free phone.
While such field studies establish a correlation- they do not imply causation- that is cell phone use causes an increase in accident rates. There may be other variables creating an association between phone use and accidents. To assess the possible causal relationship controlled experiments- such as in our study- are required.
The current study focuses on the conversation, as it comprises the majority of the time engaged in this dual task pairing. The researchers of this study sought to determine the extent phone conversations might interfere with driving and the precise nature of the interference. In particular, the peripheral-interference hypothesis, endorsed by the majority of legislative initiatives, which attributes any interference from cell phones to peripheral factors. By contrast, the attentional hypothesis attributes any interference to the diversion of attention from driving to the phone conversation.
Ok, so to summarise, the principal findings are that:
When participants were engaged in cell-phone conversations they missed twice as many simulated traffic signals as when they were not talking on the cell phone and took longer