Do people make more slips when they have been drinking alcohol?
Yes, though perhaps not in a way that you might expect. The clearest linguistic evidence of intoxication comes from slurred speech resulting from lack of muscle control in the lips and tongue. These don’t count as speech errors since the problem is physical and (strictly speaking) not cognitive. Joseph Stemberger, in an attempt to find out what does happen cognitively under the influence, ran an experiment in which subjects ingested specific amounts of alcohol, had their blood levels measured and then performed a task designed to cause errors. He found that more errors did, in fact occur. He was measuring only phonological errors though. He also found that, although the amount of errors increased, there was no evidence of new kinds of errors happening. That is, when a person is drinking, more of what can go wrong does go wrong.
