For many years I have been studying the perceptions of people. I do this to understand the limitations we face when witnessing or relaying our experiences to others. This activity is very common in paranormal research and knowing the pitfalls can certainly help.
One of the interesting idiosyncrasies I have come across involves the impact our eyes have on the things we hear. This effect can prove to be damaging in certain cases where both visual and audible senses are stimulated under chaotic conditions. For example: A witness claims that in a busy room with many people talking, they witnessed the apparition of their father saying their name. Of course there are many elements to investigate here and there may be many causes of the experience, but first we must make sure we are recording the facts of the claim correctly. The idea of whether someone “saw” an apparition is only part of the claim. What the apparition was saying is another, and it’s that element that we are addressing here today. The audible interference in the room could have an affect on the perceptions of what words are heard. Our eyes have an influence on our hearing.
Social interactions depend not only on quick, unconscious physical judgments, but on smooth communication through speech. Understanding what someone is saying requires the integration of many types of information: body language, facial expressions, speech sounds, and lip movements. But if these inputs give contrasting information, it can lead to some weird stuff.
Consider a 1976 study by Scottish psychologists Harry McGurk and John MacDonald. They showed volunteers movies of a woman’s mouth forming the shape of the sound “ga” paired with a dubbed sound of “ba.” The volunteers reported hearing “da”, showing for the first time that visual inputs strongly affect speech perception. This so-called McGurk effect has since been repeated in many experiments. Even when people know about it, as you do now, it doesn’t go away. See for yourself: