Quote:
Originally Posted by Mike F
Science disagrees:
"Drivers who talk on the phone may be "blinded" by their conversations and are more likely to cause an accident -- even if they use a hands-free cell phone. A new study shows that telephone chatting causes a unique type of "inattention blindness" that slows drivers' reaction times and may even contribute to traffic jams and air pollution."
"Researchers say talking on the phone produces a more hazardous form of distraction than conversations between the driver and other passengers in the car because the flow of in-car conversations are still dictated by the external environment, whereas cell phone conversations focus attention internally."
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Except that study didn't actually run a baseline comparison with people chatting to a passenger and see how things differed. They did four tests...response measurement to signals and three tests montioring eye movement and recollection to billboards etc.
Test 1: single task vs dual task on low and high density multilane highway. Measured following distance, brake response, accidents. That dual task was only talking on a cell phone not conversing with someone in the car. Conclusion from test 1: In low density traffic conditions there was NO effect. There was an effect in high density traffic conditions. Slight difference in brake response BARELY in the range of statisical signficance when standard error taken into account (a 12 millisec difference), brake offset isn't statisically different, longer to get up to minimum speed while conversing by ~0.25 sec, following distance increased with cell phone (upper range overlaps with other lower range for low denisty theer is some statisical significance with high density). 3 accidents in high density with cell phone use vs none without. Nothing eliminates the possibility that the more you drive the more accidents that are likely. There is no statistical significance provided for the accident number. A whopping 40 people were used.
Test 2: how cell phone conversation affects drivers attention to objects that are encountered while driving. 20 people were used. They looked at billboards as they were driving and then presented with billboards after the driving task and asked to identify as "old" or "new". Conclusion, there was a difference between single and dual task. Single task identified 6.9 +/- 0.7, dual task 3.6 +/- 0.6. Guessing rate was 0.9 +/- 0.3. They tried to relate it to traffic signals...not sure how.
Test 3: Measure eye fixations. 20 people again. Conclusion: There was no difference in eye fixation between the two tasks. There is a difference in recollection indicating that some concentration is going towards the cell phone conversation. There is no control group that shows the same thing doesn't happen when someone is talking to the person next to them or when they are singing along with music, listening to chat radio or countless other things that also take ones attention away.
Test 4: Perceptual memory tested. 200 words had to press a button if the word was an animal name. Once again 20 people. Once again the dual taks was slower to respond. However, once again the upper limit of one range overlapped with the lower limit of the other statisical range. The result is hardly of statistical significance. The difference of the means was 60 millisec. Also nothing to suggest that a different stimuli relevant to driving like oh say traffic signal colours wouldn't provide a different result.
Essentially all the numbers if you take them as statiscally significant when that is arguable for many, says the average cell phone user in this study needs an extra 3.5 feet to stop (at 40 mph) with that 60 millisec delay. What they plainly ignore in their own data is that the average following distance increases by 10-15 feet when their subjects are using the phone.
The end result is that it is actually not much of a study and the numbers hold very little statisical meaning. The results hold even less meaning because they DID NOT test other distractions such as conversing with someone else in the car, having a screaming kid in the back, singing to the music on the radio, listening to the hockey game on the radio, listening to a chat show on the radio etc etc etc. Which is why in the article you provided the Chairman of the National Safety says basically that it is information on the subject but hardly conclusive and will only say that "you need to pay attention when you are driving". Well no kidding but very few give full attention to driving and I'm sure you will have similar findings using all sorts of different distractions. Except many of those distractions would be "normal" and no one would care because they have been distraction since day one of driving cars.