McGurk effect The complex interaction between vision and hearing

Have you ever experienced the need to lower the volume to music to see the way better, while driving? At first, this behavior may seem curious, and even a bit illogical. However, this behavior corresponds to the close connection between our visual and auditory system. Thus, our senses do not work separately, but they complement each other.

The interconnection between two or more sensory systems allows a more realistic perception of our environment. However, in some cases this same interaction between senses can distort reality. In relation to this, the perceptive errors from the combination between vision and hearing are called McGurk effect.

Content

• The perception of our world is biased
• The interaction of the senses
• The McGurk effect on perception
• Curiosities on the McGurk effect
  • References

The perception of our world is biased

Perception is the process by which people interpret the signs of the world in which we live. Through this interpretation, we are able to confer meanings to our experiences. For this reason, The impression that everyone has of life is very different from that of the other. Taking into account what is already exposed, It is impossible to affirm that there is a really objective criterion about reality.

The perception is determined by two factors: biological and psychological. Biological factors refer to the faculties of our senses to capture the signals of the environment. On the other hand, psychological factors have to do with the preconceived values ​​and ideas that each one has life itself. Also, within the psychological determinants, attention intervenes. Then, these elements act as barriers between the outside world and ourselves. In such a way that they end up being filters that deform reality.

The interaction of the senses

If we break down the mechanisms that produce a bias in perception, it is essential to stop to explain the functioning of the sensory system. First, the senses have the function of obtaining information both around us, and certain internal states. Each of the senses uses an organ of the body to receive the stimuli (eyes, ears, tongue, nose and skin). However, we tend to believe that each of these sensory organs operates in a totally independent way.

The perception: when the senses deceive

Really, The information of the senses is combined in order to produce a totalized image from abroad. For example, the perception that a meal is delicious does not only come from taste itself. Rather, this impression is complemented by a good smell, thanks to the participation of smell. Even the fact that food is presented in a pleasant way could impact our perception of that meal. Thus, in the experience of eating the taste, smell and vision would be involved.

The McGurk effect on perception

Communication with the other is part of the daily life of human beings. To express ourselves effectively, We use both words and body gestures. Therefore, within the communicative process both hearing and vision intervene. Even sound and movement data are combined in the upper temporal groove of the brain to obtain a truthful message.

The fact that an effort is made to gather the most precise possible information does not mean that perception is exempt from errors.

It is common that, when we are in a noisy place, we look at the movement of the lips of our interlocutor. Many times, we can clearly capture what they try to say, but on other occasions we will end up listening to words that do not say. The first person to study this phenomenon was the psychologist Harry McGurk in 1976, with a group of children who were learning to speak. For the experiment, the researcher presented infants a video in which the audio and the image were not synchronized. As a result, phonemes were heard that did not correspond to the sound or the images.

Thanks to this study, it was discovered what we now know as a mcgurk effect. This occurs when The auditory component of a sound is matched to the visual component of another sound. As a consequence of such a situation, the perception of a third non -existent sound is presented. For example, a person pronounces the syllable /pa /, but the lips move as if he were going to say /ka /. What would be obtained from such combination is the impression that the interlocutor is really articulating the phoneme /ta /.

Curiosities on the McGurk effect

It is important to clarify that, the intensity with which the McGurk effect varies from person to person. To begin with, the mother tongue plays an important role, it is shown that Asian languages ​​affect them with less intensity. The Chinese and Japanese are less likely to experience McGurk effect, Well, his tongue is extremely syllabic, so they show greater ability to read the lips.

As a curiosity, individuals who have suffered brain injuries do not usually experience the phenomenon corresponding to the McGurk effect. Similarly, children with literacy disorders live the effects of this phenomenon in a much weaker way. Besides, skilled people look much more affected by the McGurk effect than left -handed.

To conclude, it is important to take into account how the entire sensory-perceptual system is correlated. In this sense, the formation of a unitary image helps people to understand the world. However, it is necessary to emphasize that both our senses and our perception can fail, generating illusory effects such as McGurk.

References

• Harry McGurk and John Macdonald, "Hearing Lips and Seeing Voices," Nature 264: 5588 [1976], 746.
• Alsius, a., Navarra, j. and Soto-Faraco, S. (2007). Attention to touch weakens the integration of audiovisual speech. Experimental brain research, 183 (3), 399-404.
• Boersma, p. (2012). An explanation based on restrictions on the McGurk effect. Phonological architecture: empirical, theoretical and conceptual issues, 299-312.
• NATH, AR AND BEAUCHAMP, MS (2012). A neuronal base for interindividual differences in the McGurk effect, an illusion of multisensory speech. Neuroimagen, 59 (1), 781-787.
• Sekiyama, k. (1997). Cultural and linguistic factors in audiovisual speech processing: the McGurk effect on Chinese participants. Perception and psychophysics, 59 (1), 73-80.
• Sekiyama, k. and Tokura, Yi (1991). McGurk effect on listeners who do not speak English: few visual effects for Japanese participants who listen to Japanese high -intelligibility Japanese syllables. The newspaper of the acoustic society of America, 90 (4), 1797-1805.