OK, so texting while driving isn’t safe, right? We’ve been told time and again not to do it, but a CDC report indicates 31 percent of US drivers admit to sending or receiving texts while behind the wheel. Although the figure is an improvement over the 68 percent of drivers who admit to talking on the phone while driving, it’s still pretty scary to think three out of every 10 cars on the road may be operated by someone who’s more focused on a message than properly directing what basically amounts to a bomb on wheels.

AAA offers similar figures, with about 35 percent of drivers admitting to reading at text or email while driving at least once during any given month, and 26 percent typing one. Even though the majority of states now ban texting and driving, we still do it. Are we stupid or just stubborn? Maybe a little of both. Since I mastered applying mascara while driving down a twisty mountain road to school at age 16, surely I can send a message while I’m on the straight and wide highway, right? Especially if I have Siri to help me out?

Wrong. A past study from the University of Utah found that drivers talking on cell phones—whether handheld or hands-free—experienced slower brake times and were involved in as many simulated accidents as participants who registered a .08-percent blood alcohol level. And the same researchers have shown that talking on a hands-free device is markedly different than talking to a passenger in the vehicle, contrary to popular belief. According to University of Utah’s David Strayer, conversations with passengers in the car often incorporate traffic into the discussion or change course based on the complexity of the driving situation. If the driver needs to slam the brakes, for example, the passenger will respond to the situation. But drivers communicating on hands-free devices create weak memories of objects in the driving environment, suggesting a great deal of attention is taken away from the road.

A new study from the Texas Transportation Institute at Texas A&M University compared voice-to-text and traditional texting in a driving experiment. Study lead Christine Yager told Reuters drivers took twice as long to react during both scenarios compared to when they were not texting.

“Eye contact to the roadway decreased, no matter which texting method was used,” she said.

In the study, 43 participants drove along a test track with no electronic devices. Then the same participants drove along the same track while texting and again while using a speech-to-text device such as Siri. According to Yager, drivers using the speech-to-text device actually responded slower than when they used traditional texting because of their need to correct errors in the electronic transcription.

“You’re still using your mind to try and think of what you’re going to say, and that by proxy causes some driving impairment, and that decreases talk time,” she said.

Likewise, drivers using text-to-speech felt a false sense of security and were less on their guards than when they were manually texting messages.

Still, automobile manufacturers are working with researchers to implement mobile communication technology into their vehicles.

“Every day, new technologies come out, and it is important to educate the public that even these seemingly new distractions are still distractions, and it will help people be safer when they get into the vehicle,” Yager said.

Apple is working with several manufacturers on an “eyes free” option that allows users to speak to their cars with a special Siri button on the steering wheel. And in hands-free mode, the iPhone screen stays off, so it cannot distract the driver. Few have implemented the option, however, and the new research casts doubt on whether it should be offered at all.