2018年6月大学英语六级听力常考时文：Seasonal Affective Disorde思维导图

SeasonalAffectiveDisorde

Somepeoplefeelsadordepressedduringthewintermonthsinnorthernareasoftheworld.Theymayhavetroubleeatingorsleeping.TheysufferfromaconditionknownasSeasonalAffectiveDisorder,orS-A-D.VictimsofS-A-Dsufferitseffectsduringtheshort,darkdaysofwinter.Theproblemsaremostsevereinthemonthswhentherearefewerhoursofdaylight.Whenspringarrives,thesesignsdisappearandS-A-Dvictimsfeelwellagain.TheNationalMentalHealthAssociationreportsthatS-A-Dcanaffectanyone.Thegroupsaysyoungpeopleandwomenareatthehighestriskforthedisorder.Itsaysthatanestimated25percentoftheAmericanpopulationsuffersfromsomeformofS-A-D.About5percentsufferfromasevereformofthedisorder.Manypeopleinotherpartsoftheworldalsohavethecondition.Theideaofhealthproblemslinkedtoalackoflightisnotnew.Scientistshavediscussedtheissuesincethebeginningofmedicine.Morethantwo-thousandyearsago,theGreekdoctorHippocratesnotedthattheseasonsaffecthumanemotions.Today,expertsdonotfullyunderstandS-A-D,andyettheyagreethatitisaveryrealdisorder.Totreatthedisorder,victimsofS-A-Ddonotneedtowaituntilspring.Expertsknowthatplacingaffectedindividualsinbrightlighteachdayeasesthecondition.Thereareotherthingspeoplecandotoeasetheproblem.Theycanincreasethesunlightintheirhomesandworkplacesandspendmoretimeoutdoorsinthefreshairduringtheday.Onestudyfoundthatwalkingforanhourinwintersunlightwasaseffectiveasspendingtwo-and-one-halfhoursunderbrightlightindoors.