Source: http://upload.wikimedia.org/wikipedia/commons/ 8/86/ Texting.jp g
As members of a social networking generation, we have all used the ubiquitous “:-)” smiley in one of its many forms. The reason for the exploding use of such smilies may vary from personalization to habit, but the emoticon’s widespread presence is due to their association with human faces.
In fact, researchers in South Australia led by Owen Churches believe that people may process emoticons in the same way they process human faces (1).
When a person processes a human face, his or her occipitotemporal cortex reveals negative electrical activity between 130 to 200 ms after presentation of the stimulus. This averaged electrophysical response was coined as the N170 event-related potential (ERP). The N170 ERP relies on both featural processing of individual features in the lateral brain regions and configural processing of the combination and relationships of multiple features in the middle fusiform.
Thus, to study how humans process emoticons, Churches and his team decided to compare the electroencephalograms of 20 participants presented with emoticons, faces, and meaningless combination of characters (1). Each participant viewed six different types of stimuli in 60 different fonts: an emoticon represented by “:-)”, an inverted emoticon “(-:”, a smiling human face, an inverted smiling human face, a meaningless string of characters “*/.”, and a 180 degree inversion of the characters. Participants were also presented with 30 upright pictures of flowers as a control.
The results of the EEGs revealed that humans show similar N170 patterns when they see upright emoticons as when they see upright faces. Scientists found an increased N170 ERP amplitude for emoticons compared to faces for both the upright and inverted orientations. However, the “*/.” characters in either orientation failed to produce a significant N170 ERP because no facial recognition was involved (1).
When human faces are inverted, the latency of the N170 response increases due to increased face featural processing in the lateral areas of the brain and reduced configural processing, which cannot process inverted stimuli as faces. However, emoticons in either orientation showed insignificant change in latency of the N170 response. Instead, inverted emoticons produced a decreased amplitude of the N170 response due to the lack of both featural and configural processing, suggesting that humans do not perceive inverted emoticons as faces (1).
Researchers believe that face recognition of emoticons is done entirely by configural rather than featural processing, since the individual typographic features (“:” and “-” and “)”) are not processed as eyes, nose, and mouth when presented separately. When “:-)” is perceived as a face, this is done by configural processing by integrating the separate features (1).
While the implications of the study are not quite clear, researchers see many directions of further exploration: First, the findings that emoticons invoke a greater N170 ERP response than human faces bring up the issue of attention on the electrophysical response. Second, while this study focused on a single emotion, happiness, future studies could explore various other emotions. Third, the effect of different orientations other than the 180 degree inversion could produce different N170 ERPs.
Researchers are also interested in looking deeper at the N170 ERP, which does not reflect the lateralization of face-perception of configural processing in the right hemisphere and featural processing in the left hemisphere. While this suggests that the N170 response should be much larger in the right hemisphere for the upright emoticon stimuli, researchers failed to see this result (1).
References:
1. O. Churches, M. Nicholls, M. Thiessen, M. Kohler, H. Keage, Emoticons in mind: An event-related potential study. Social Neuroscience.9, 196-202 (2014).