Scientists have come up with a theory for why time flies when you are having fun and drags when you are bored. Scans have shown that (62) of activity in the brain change depending on how we focus on a task. Concentrating on time passing, as we do when bored, will (63) brain activity which will make it seem as though the clock is ticking more () . The research, by the French Laboratory of Neurobiology and Cognition, is published in the magazine Science. In the study, 12 volunteers watched an image while researchers (65) their brain activity using MRI(核磁共振成像) scans. Volunteers were given a (66) of tasks. In one they were told to concentrate simply on the duration of an image, in (67) they were asked to focus on the (68) , and in a third they were asked to concentrate on both duration and color. The results showed that a network of brain regions was (69) when more subjects were paid attention to duration. It is thought that if the brain is busy focusing on many aspects of a task, then it has to spread its resources thinly, and pays less (70) to time passing. Therefore, time passes without us really (71) it, and seems to go quickly. (72) , if the brain is not stimulated in this way, it concentrates its (73) energies on monitoring the passing of time. This may make time seem to (74) , but in fact it is probably a more accurate perception of reality. (75) the researchers found that the more volunteers concentrated on the duration of the images, the more (76) were their estimates of its duration. Lead researcher Dr. Jennifer Coull said many of the areas of the brain (77) in estimating time were the same that played a key role in controlling movement, and (78) for action. She said this overlap suggests that the brain may make sense of time as (79) between movements, in much the same way (80) musicians mark time with his foot, or (81) anticipate the sound of a starter’s pistol.

CT定位扫描获得后前正位定位相的患者位置应该是