Disappointment circuits

Just finished reading a paper published at the Department of Pharmacology . . Univ . of Washington . "Bright light activation between 11:00 p . m . and 4:00 a . m . . . sends a signal from the eye to brain structure called the habenula . . it kicks off a disappointment circuit . . it start suppressing dopamine . . and the habenula is linked to the pancreas . . and starts justs disregulating blood sugar . . " Me-trigger disappointment? And just like that i was hooked . . In the article . . "every circuit in the brain has a push and a pull . . so we have a reward system for viewing light . . at the particular times of day . . but there's a punishment signal . . a chemical punishment signal . . whereby dopamine . . which is this feel good molecule . . is suppressed . . when human beings or animals view bright light in the middle of this dark phase of the circadian cycle . . ...