After a Stroke, a Scientist Studies Herself : NPR
Neurological researcher Jill Bolte Taylor suffered a stroke 12 years ago. While the damage caused by a stroke is often devastating, Taylor was able to make a complete recovery after becoming her own experimental subject.
One of the insights here is that at any given moment, the right part of the brain is "present" evoking those (those "blue sky" thoughts) but is often ecclipsed, by the left brain hemisphere which is focused on more linear, logical type thinking which may incorporate both past and future. This prevents one from being "present" in the moment. The left hemisphere, are those "clouds" that may prevent one from seeing the "blue sky", which is always there in plain sight. Pretty fascinating insight!
See on www.npr.org