Occipital lobe: Definition, function, and linked conditions

The occipital lobe is one of the four major lobes in the mammalian brain. The occipital lobe is mainly responsible for interpreting the visual world around the ... MedicalNewsTodayHealthConditionsDiscoverToolsConnectSubscribeEverythingyouneedtoknowabouttheoccipitallobeMedicallyreviewedbySeungguHan,M.D.—WrittenbyJonJohnsononMay22,2020DefinitionFunctionLinkedconditionsSummaryTheoccipitallobeisthepartofthehumanbrainresponsibleforinterpretinginformationfromtheeyesandturningitintotheworldasapersonseesit.Theoccipitallobehasfourdifferentsections,eachofwhichisresponsiblefordifferentvisualfunctions.Disorderintheoccipitallobemaycausedisorderinthevisionorthebrainitself.Theremayalsobealinkbetweentheoccipitallobeandconditionssuchasepilepsy.Readontolearnmoreabouttheoccipitallobe,includingitsspecificfunctions.Whatisit?Theoccipitallobeisoneofthefourmajorbrainlobepairsinthehumanbrain.Theoccipitallobeissonamedbecauseitrestsbelowtheoccipitalboneoftheskull.Itisalsothesmallestofthelobes.Thereareactuallytwooccipitallobes—oneoneachhemisphereofthebrain.Thecentralcerebralfissuredividesandseparatesthelobes.Theoccipitallobesarelocatedontherearpartoftheupperbrain.Theysitbehindthetemporalandparietallobesandabovethecerebellum,separatedfromthecerebellumbyamembranecalledthetentoriumcerebelli.Thesurfaceoftheoccipitallobeisaseriesoffolds,includingridgescalledgyrianddepressionscalledsulci.Becausethereisnoorderedstructuretotheoccipitallobe,scientistsusethesesulciandgyritoidentifytheareaofthelobe.Apartfromthese,therearenostructuraldistinctionsinthelobes.Scientistsseparatethelobesfurtherbasedonbasicfunction.Theoccipitallobeitselfcontainsdifferentsections,orareas,andeachofthesehasadifferentsetoffunctions.Theseinclude:thelateralgeniculatebodiesthelingulatheprimaryvisualcortex,knownasBrodmannarea17orV1thesecondaryvisualcortex,knownasBrodmannareas18and19orV2,V3,V4,V5,whichsurroundstheprimaryvisualcortexthedorsomedialstreamFunctionIngeneral,theoccipitallobedealswithaspectsofvision,including:distancedepthperceptioncolordeterminationobjectrecognitionmovementfacerecognitionmemoryinformationHumansalsohavebinocularperceptionduetothefactthattheoccipitallobesoneitherhemispherealsoreceivevisualinformationfrombothoftheretinas.Becausethiscombinestwoimagesintooneimageinthebrain,ithelpsgivemoredepthandprovidespatialawarenessoftheenvironment.Thatsaid,thevisualworldishighlycomplex.Becauseofthis,theprocessofdecodingthisinformationisalsoverycomplex.Thesectionsbelowwilldiscussthedifferentsectionsoftheoccipitallobeinmoredetail.PrimaryvisualcortexTheprimaryvisualcortex,calledBrodmannarea17orV1,receivesinformationfromtheretina.Ittheninterpretsandtransmitsinformationrelatedtospace,location,motion,andcolorofobjectsinthevisualfield.Itdoesthisthroughtwodifferentpathwayscalledstreams:theventralanddorsalstreams.SecondaryvisualcortexThesecondaryvisualcortex—calledBrodmannarea18and19orV2,V3,V4,V5—receivesinformationfromtheprimaryvisualcortex.Thesecondaryvisualcortexdealswithmuchofthesametypeofvisualinformation.VentralstreamTheventralstreamisonepathwaytheprimaryvisualcortexusestosendinformation.Ittakesinformationtothetemporallobe,whichinterpretstheinformationandhelpsthebraingivemeaningtoobjectsinthefieldofvision.Thishelpswithobjectrecognitionandgivesconsciousawarenesstowhatapersonisseeing.DorsalstreamThedorsalstreamistheotherpathwaytheprimaryvisualcortexusestosendinformation.Itsharesinformationaboutanobject’slocationandcarriesittotheparietallobe,whichtakesinotherinformationaboutthespaceandshapeofobjectsinthefieldofvision.LateralgeniculatebodiesThelateralgeniculatebodiestakepartoftherawinformationfromtheouterpartoftheretinatothevisualcortex.LingulaThelingulagathersgeneralinformationaboutthefieldofvisionfromtheinsidehalfoftheretina.Thecombinationofinformationfromthelateralgeniculatebodiesandthelingulahelpscreatespatialawarenessandgivesdepthtothevisualinformation.OthercontributingsectionsAlthoughmodernsciencehasrevealedmuchabouthowtheoccipitalloberevealsthevisualworld,researchersarestilllearningnewinformationabouttheoccipitallobeandexactlyhowitfunctions.Nosectionofthebrainistrulyindependent,andthisincludestheoccipitallobe.Forexample,theoccipitallobetakesinformationfromtheretinaintheeyeandtranslatesitintothevisualworld.Assuch,itreliesheavilyontheeyesthemselves.Theeyesthemselvesalsohavemusclesthatneedcontrolling.Themotorcortexinthebrainisresponsibleforthesemovements,thereforealsoplayingaroleinvision.Thetemporalandoccipitallobesshareimportantinteractions,aswell.Thetemporallobegivesmeaningtotheinterpretedvisualinformationfromtheoccipitallobe.Italsostorestheinformation,toadegree,intheformofmemories.Insomecases,itmayalsobepossibleforothersectionsofthebraintocompensateforanydamageaffectingtheoccipitallobe.LinkedmedicalconditionsDysfunctionintheoccipitallobemayleadtooneormoredysfunctionsinthebrain,vision,oreverydayfunctioning.Itmaycauseorcontributetoanyofthefollowingconditions.BlindnessBecausetheoccipitallobedealswithvision,onepossibleresultofdamageinthisareaisfullorpartialblindness.Lossofsightisnotalwaysstraightforward,however,andthepersonmayinsteadloseoneormorespecificfunctionsoftheirvision.AntonsyndromeAntonsyndromeisarareformofblindnessthatoccurswithoutthepersonbeingawareofit.Theymaydenytheirvisionloss,evenifahealthcareprofessionalpresentsevidenceshowingthattheyhavevisionloss.RiddochsyndromeRiddochsyndromeisarareconditioninwhichapersonisonlyabletoseemovingobjects.Stationaryobjectssimplydonotappearintheirfieldofvision.Thepersoncanalsonotperceiveshapeorcolor.EpilepsyEpilepsysharesalinkwiththeoccipitallobeinsomecases.Ifapersonismorepronetooccipital-typeseizuresorphotosensitivityseizures,flashesoflightorimagesthatcontainmultiplecolorsmaytriggertheseseizures.OtherformsofdysfunctionThetypeofdysfunctiontoaffectthebodycanvarybasedonwherethedysfunctionorinjuryoccursintheoccipitallobe.Somepossibleexamplesinclude:difficultyrecognizingeverydayobjectstroubleunderstandingbasiccolors,shapes,orsizesdifficultyrecognizingfamiliarfacesdifficultybalancing,moving,orstandingvisualhallucinations,suchasflashesoflightchangesindepthperceptiondifficultydetectingmovingobjectsdifficultyreadingorwriting,duetotroublerecognizingwordsSummaryTheoccipitallobeisoneofthefourmajorlobesinthemammalianbrain.Theoccipitallobeismainlyresponsibleforinterpretingthevisualworldaroundthebody,suchastheshape,color,andlocationofanobject.Itthenrelaysthisinformationtootherpartsofthebrain,whichgivethisvisualinformationitsmeaning.Dysfunctionintheoccipitallobemaycauseanumberofbodilydysfunctions,suchasirregularvision,difficultystanding,andblindness.Someconditions,suchasepilepsy,mayalsohavealinktodysfunctionintheoccipitallobe.LastmedicallyreviewedonMay22,2020Biology/BiochemistryNeurology/Neuroscience3sourcescollapsedMedicalNewsTodayhasstrictsourcingguidelinesanddrawsonlyfrompeer-reviewedstudies,academicresearchinstitutions,andmedicaljournalsandassociations.Weavoidusingtertiaryreferences.Welinkprimarysources—includingstudies,scientificreferences,andstatistics—withineacharticleandalsolistthemintheresourcessectionatthebottomofourarticles.Youcanlearnmoreabouthowweensureourcontentisaccurateandcurrentbyreadingoureditorialpolicy.Galetta,S.L.(2017).Occipitallobe[Abstract].https://www.sciencedirect.com/science/article/pii/B9780128093245038104Rehman,A.,&AlKhalili,Y.(2019).Neuroanatomy,occipitallobe.https://www.ncbi.nlm.nih.gov/books/NBK544320/Todorov,O.S.,&deSousa,A.A.(2017).Evolutionoftheoccipitallobe.https://www.researchgate.net/profile/Alexandra_De_Sousa3/publication/322122237_Evolution_of_the_Occipital_Lobe/links/5d00f5e0299bf13a384ff7b4/Evolution-of-the-Occipital-Lobe.pdfFEEDBACK:MedicallyreviewedbySeungguHan,M.D.—WrittenbyJonJohnsononMay22,2020LatestnewsHepatitisoutbreakinchildren:600+casesworldwide,causeremainsamysteryInConversation:Canpsychedelicsrewireadepressed,anxiousbrain?ADHDinkids:EatingmorefruitandvegetablesmayreduceinattentionIntermittentfasting:Isitallit'scrackeduptobe?Cancerandahighfatdiet:What'sthelink?RelatedCoverageEverythingyouneedtoknowaboutthecerebellumMedicallyreviewedbyJ.KeithFisher,M.DThehumanbrainisahugelycomplexorgan,madeofdifferentareasthathandledifferentfunctions.Thecerebellumisthepartthathandlesmany…READMOREAllaboutthecentralnervoussystemMedicallyreviewedbySeungguHan,MDThecentralnervoussystemismadeupofthebrainandspinalcord.Itgathersinformationfromalloverthebodyandcoordinatesactivity.Weexplore…READMOREWhattoknowaboutepilepsyMedicallyreviewedbyHeidiMoawad,MDEpilepsyisafairlycommonneurologicalconditioncharacterizedbyrecurrentseizures.Inthisarticle,learnaboutthedifferenttypesofepilepsy…READMOREWhattoknowaboutepilepsyinchildrenMedicallyreviewedbyNancyHammond,MDEpilepsyisaconditionthatcausesseizures.Itisrelativelycommoninchildren.Learnaboutitscauses,symptoms,andtreatmentshere.READMOREWhatdoesthefrontallobedo?MedicallyreviewedbySeungguHan,MDThefrontallobeisapartofthebrainthatcontrolskeyfunctionsrelatingtoconsciousnessandcommunication,memory,attention,andotherroles…READMORE