Does time seem to fly by when you’re having fun and drag when you’re not? Research by Marc Whittmann of Germany and colleagues suggests that one’s sense of time intervals in the range of seconds is directly related to activity in the insular cortex. In each cerebral hemisphere, the insular cortex is located within the lateral sulcus, a fissure that separates the temporal lobe from the parietal and frontal lobes of the cerebral cortex. The insular cortex contains the primary sensory area for interoception—sensitivity to stimuli that originate inside the brain and body. According to Whittmann, neural processes in the insular cortex, which are related to body signals, feeling states as well as to self-consciousness, constitute neurophysiological mechanisms for the creation of subjective time. Increasing neural activity in the insular cortex, which is associated with feeling states of the body and emotions, may be related to the cumulative representation of time—the way in which a specific brain perceives how much time passed. No wonder time perception can be so subjective!