This is a task in which a
participant hears, via
headphones, two
words or two
sounds (such as
laughter and a
siren) simultaneously, one in each ear. The participant then indicates which word or sound they heard most
distinctly. Sometimes the participant hears a
combination of words (such as "water" when given "worry" and "brother") or is unable to
distinguish which word or sound is more distinct.
The purpose of this experiment is to determine which side of a person's brain is being predominantly used for the purpose of understanding words. A right-hand dominant person would be expected to hear more words spoken from the right side, which indicates that the left side of the brain is being used to process lingual sounds. Right-handed people are also expected to hear non-lingual sounds more clearly through the left ear. Left-handed people are expected to have less lateralized processing.
There are a number of circumstances that can compromise the results of this experiment. One is the possibility that the quality of hearing will be better in one ear. Another is than when a participant is more familiar with one word than the other, they may tend to focus on the more familiar term. The same situation may occur with sounds; when given laughter and a siren, the participant may hear the siren more clearly because the sound is identified with alarm and because they are used to hearing laughter that does not merit attention. Other interferences could be caused by the quality of equipment used to administer the test or errors in synchronization of the words.