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 mise à jour du
24 février 2002
Sleep research
1991; 20;1 16
 Le bâillement, du réflexe à la pathologie
 Yawning elicited by reading : is an open mouth sufficient stimulus ?
 Mary A Carskadon
Sleep Revearch Laborarory, EP Bradley Hospital
Brown University, Providence, RI
Yawning elicited by reading: effects of sleepniness Carskadon MM
 Is yawning an arousal defense reflex ? Askenasy JJ
 Yawning: an evolutionary perspective Smith EO


Provine has shown that reading about yawning is a releasing stimulus or elicitor of yawns: college students were more likely to report yawning while reading a passage about yawning than while reading a control passage about hiccups. Provine also examined the nature of the visual stimuli that elicit yawning and suggested that the full facial configuration is the most potent visual releaser, more so than a yawning mouth alone. We whish to examine whether reading about yawning is a specific releaser of yawning or reading about opening the mouth for another pupose might effective as well. Based upon the visual stimulus data, we hypothesized that the likehood of eliciting yawns, by reading about yawning would be unrelated to the individual's level of interest in the material or level of alertness, whereas yawning in response to another textual stimulus might show a relationship to those factor (boredom and sleepiness)

Methods : While seated in a largte auditoriem, students enrolled in a course on sleep and dreaming but naive to information on yawning were given one of two brief passages to read, with instructions to "remain absolutely quiet and do not look around the room" while reading. A 5-minute reading period was provided, and students were instructed to re-read the passage if they finished early. One passage ("Yawn") described yawning and was the passage previously used by Provine. The second ("Open Wide") was of equal length, but described tonsils and tonsillitis in the context of explaining why a doctor says "open wide and say ah". Subjects were then requested to answer questions about whether they yawned, were tempted to yawn, did not yawn, or could not remember having yawned. while reading the text. They also rated their interest level in the reading and stated how much they had slept the night before. Responses were completed by 119 students, 61 women and 58 men. ranging in age from 19 to 26 (mean =2 20.1. S.D. = 1.1) years. The Yawn text was read by 60 students (31 women, 29 men) and the Open Wide toxi by 59 (30 women, 29 men). No sex differences were found; therefore, the data were combined across sexes.

Results : As shown in the figure students who read the Yawn passage reported yawning or having been tempted to yawn significantly more often than those who read the open Wide passage (chi-square = 17-90; p<.001), Reprted sleep time was not significant predictor of yawning in either gropu. The rported level of intereest in the reading material was significantly related to reports of yawning in the gropu who readthe open wide passage (chi-square = 10,77; p<0,1), with 12 of 20 who reported low interest (1 or 2 on a 5 point scale) reporting yawning or being tempted to yawn versus 5 of 31 who reported a moderate or high level of inyererst (3,4 or( on the same scale). Level ofinterest was not significant factor in reports of yawning behavior of the group who read the yawn passage.

Discussion : Reading about yawingg was significantly more likely to elicit yawning behavior than reading about opernng the mouth per se. This finding supports the specificity of the cognitive releasing stimulus for yawning. Sleep length on the previous night was unrelated to likelihood of yavming, from which one may infer that alertness level was not a significant interveningvariable. On the other hand a more direct measure of alertrness is required to eliminate this factor entirely, since alertness level has other determinants that were not assessed in this study. The relationship of interest level to yawning is also of some note. Previous work has found that yawning occurs more frequently in a boring than a stimulating environment. Our results showed that bordom was a significant factor contributing to yawning in response to a non specofic stimulus but not when specifically reading about yawning.