ed ▁positive ▁versus ▁negative ▁m ood : ▁▁▁ ▁A ▁series ▁of ▁related ▁studies ▁suggested ▁a ▁link ▁between ▁positive ▁m ood ▁and ▁the ▁promotion ▁of ▁cogn itive ▁flex ibility . ▁ ▁In ▁a ▁ 1 9 9 0 ▁study ▁by ▁Murray , ▁Su jan , ▁H irt ▁and ▁Su jan , ▁this ▁hypothesis ▁was ▁exam ined ▁more ▁closely ▁and ▁" found ▁positive ▁m ood ▁participants ▁were ▁able ▁to ▁see ▁relations ▁between ▁concepts ”, ▁as ▁well ▁as ▁demonstr ating ▁advanced ▁ab ilities ▁" in ▁distingu ishing ▁the ▁differences ▁between ▁concepts ". ▁ ▁This ▁group ▁of ▁research ers ▁drew ▁a ▁parallel ▁between ▁" the ir ▁find ings ▁and ▁cre ative ▁problem ▁solving ▁by ▁arg uing ▁that ▁participants ▁in ▁a ▁positive ▁m ood ▁are ▁better ▁able ▁both ▁to ▁differenti ate ▁between ▁and ▁to ▁integrate ▁unusual ▁and ▁diverse ▁information ". ▁ ▁This ▁shows ▁that ▁their ▁subjects ▁are ▁at ▁a ▁distinct ▁cogn itive ▁advantage ▁when ▁performing ▁diver gent ▁thinking - related ▁tasks ▁in ▁an ▁elev ated ▁m ood . ▁Further ▁research ▁could ▁take ▁this ▁topic ▁one ▁step ▁further ▁to ▁explore ▁effective ▁strateg ies ▁to ▁improve ▁diver gent ▁thinking ▁when ▁in ▁a ▁negative ▁m ood , ▁for ▁example ▁how ▁to ▁move ▁beyond ▁" optim izing ▁strateg ies " ▁into ▁" s atisf icing ▁strateg ies " ▁rather ▁than ▁focus ▁on ▁" the ▁quality ▁of ▁their ▁ideas ", ▁in ▁order ▁to ▁generate ▁more ▁ideas ▁and ▁cre ative ▁solutions . ▁ ▁Effect s ▁of ▁sleep ▁dep riv ation ▁ ▁While ▁little ▁research ▁has ▁been ▁conducted ▁on ▁the ▁impact ▁of ▁sleep ▁dep riv