From Discover magazine: “Unrealistic optimism refers to the pervasive tendency of healthy individuals to underestimate their likelihood of future misfortune, including illness. The phenomenon shares a qualitative resemblance with anosognosia, a neurological disorder characterized by a deficient appreciation of manifest current illness or impairment.”
Are you too optimistic? Science can fix that. (Discover Magazine)
See also:
Vestibular stimulation attenuates unrealistic optimism. (Cortex)