Starting in the late 1960’s, scientists began to conduct experiments on the human brain to begin to localize which areas in the brain were in charge of processing and conducting certain activities. They discovered that the two hemispheres of the human brain are extremely specialized in their function and activity. Specifically, with sound processing and perception, they discovered that the left hemisphere of the brain is nearly always responsible for speech processing, and the right hemisphere is nearly always responsible for music perception, processing, and musical ability. There are exceptions. However, 95-96% of right-handed males have their language processing ability localized in the left hemisphere. For women, the statistic is somewhat diminished. Also, it has been found that individuals who have highly developed musical abilities are more likely to be able to process musical stimuli with either both hemispheres or solely in the left, where language processing is generally localized.
One of the methods these scientists used to discover this information involved conducting dichotic listening exercises on test subjects. A subject would listen to two different auditory stimuli at one time, where one sound was played in one ear through headphones, and another in the other ear. The side that the subject responded to for certain stimuli would determine which side of the brain was being used during the process. However, it was discovered that the left ear actually corresponds to the right hemisphere and vice versa (just as the left arm corresponds to the right hemisphere). This relationship is called a contralateral relationship.
This sound piece represents my attempt to recreate the sound experiments performed by these scientists. The work is divided into several sections. The first section involves several short musical selections. The first dichotic selection contains two different melodies, one for each channel of audio. The subject must determine if the first two melodies match any of the subsequent pairs of musical selections, and must specify which side it is heard on. Results should show that there is a right hemisphere (left ear) advantage in melody discrimination in general for most people.
The next section consists of two different types of brain teasers. One is verbal in nature; the other is visuo-spatial. The subject must answer one of the questions asked according to which they were most able to process. The results should show that the right hemisphere (left ear) has an advantage for questions that require visuo-spatial processing, and the left hemisphere (right hear) had an advantage for speech processing.
The following section consists of several speech processing exercises. There are three pairs of words played dichotically. The subject has several objects in front of him/her to choose from according to the information given by the pair of words. Most people should show a left ear (right hemisphere) advantage since the task requires predominantly visuo-spatial processing.
This series of exercises can be quite frustrating. Trying to listen to two different stimuli at one time can be a little wearing on one’s nerves. Editing this piece, I can tell you, was very frustrating because I had to listen to each of the exercises ad nauseum (can we say sound torture!?!) So, just for fun, the second act of the piece represents my personal experience in the research and editing process. The piece itself takes advantage of some of the principles of cerebral hemispheric dominance in the way that some of the sounds are panned to the corresponding side of the brain that would most likely process it. Enjoy!
Ü To hear this project, click here!!!