Electroencephalographic insights into affective attention
Kuupäev
2014-05-09
Autorid
Ajakirja pealkiri
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Abstrakt
Miks ilus inimene rahvasummas silma jääb? Või ka kauguses kostuv pidurikrigin liiklusmürast üle kostab? Tartu Ülikoolis valminud doktoritöö kohaselt võib põhjuseks olla emotsionaalse informatsiooni kiirendatud töötlus.
Aju on varustatud tähelepanumehhanismidega, mis valivad meeleorganite vahendatud infotulvast välja kõige olulisema teabe. Näiteks tahtlik tähelepanu aitab keskenduda käesolevale ning tahtmatu tähelepanu märgata ootamatusi. Neile sekundeerib ka kolmas süsteem, mis tõstab esile emotsionaalse tähendusega infot. Just afektiivne tähelepanu viib fookuse potentsiaalsetele hüvedele nagu kaunis kaaslane ja ohtudele nagu liiklusõnnetus.
Seni on aga lahendamata küsimus, mis täpselt toimub ajus siis, kui erinevad tähelepanusüsteemid omavahel konkureerivad. Näiteks kui veebiuudise lugeja silm haarab ühtaegu nii pooleliolevat teksti kui mahlakat kõmupealkirja külgribal. Mõnikord jääb võitjaks emotsionaalne tähelepanu ning kõmulugu saab oodatud kliki. Teinekord suudab aga tahtlik tähelepanu ebaolulise ahvatluse kõrvale tõrjuda ja loo lugemine võib jätkuda.
Oma doktoritöös uuris Andero Uusberg lähemalt võimalust, et tähelepanulises võistluses toimub esimese sekundikolmandiku jooksul liidritevahetus. Emotsionaalne tähelepanu reageerib stardis kiiremini, kuid umbes 350 ms järel on tahtlik süsteem seisu viigistanud ning aju fookust juhitakse edaspidi koostöös. Mitmed selle mõttemudeli ennustused leidsid kinnitust emotsionaalse sisuga fotode vaatamise ajal mõõdetud aju elektrilise aktiivsuse analüüsimisel. Üldisemalt aitab tähelepanusüsteemide erinev stardikiirus seletada, miks tegelikkuses ohutud stiimulid nagu kauge pidurikrigin kipuvad siiski tähelepanu haarama – kulub hetk, ette kui konteksti arvestav tahtlik tähelepanu jõuab korrigeerida primitiivsema emotsionaalse süsteemi esialgset valikut.
Doktoritööst leiab ka vihjeid igapäevaseks emotsioonide reguleerimiseks. Ebameeldiva raviprotseduuri või muu ärevust tekitava olukorraga toimetulemiseks soovitatakse vahel mõelda millestki muust. Uusbergi uurimistöö näitas aga, et selline strateegia on suurema tõenäosusega edukas siis, kui mõte juhitakse millelegi piisavalt keerukale. Näiteks kui katseisikutel paluti võimalikult detailirohkelt kujutleda jalutamist kodulinnas, vähenes samal ajal esitletud emotsionaalsete piltide sisusse süvemine ning neile reageerimise intensiivsus. Kui ülesandeks oli aga keskenduda emotsionaalsete piltide neutraalsetele omadustele, vähenes afektiivne tähelepanu vaid mõnevõrra.
Why does a beautiful face stand out from a crowd? Or even a distant braking screech captures attention? A recent doctoral thesis suggests the reason may be faster processing of emotional information. The brain is equipped with various attention mechanisms for sorting out important information from potentially overwhelming sensory input. While top-down attention enables us to concentrate and bottom-up attention to remain vigilant for unexpected aspects of the environment, there is also a third system sensitive to emotional information. This affective attention is responsible for spotting opportunities such as a valuable mate or threats such as a traffic accident. Scientists do not fully comprehend however, how does competition between attention systems is resolved in the brain. As an example, consider a reader of an online news story whose eyes also capture a juicy headline at a sidebar. Sometimes affective attention succeeds in breaking the concentration on the story in favour of the emotional distraction. At other times however, top-down attention prevails and reading continues uninterrupted. In his thesis, Andero Uusberg investigated the idea that the competition between attentional systems changes across time. More specifically, affective attention may be faster off the mark while after about a third of a second however, top-down attention catches up and the subsequent focus is determined in co-operation. This framework explained several aspects of electrical brain activity measured while participants viewed emotionally evocative photographs. More broadly, different onsets can explain why safe stimuli such as a distant braking screech still captivates us – it takes a moment for the more context-aware top-down attention system to correct the early reaction of the more primitive affective attention. The thesis also has implications for everyday emotion regulation. To cope with unpleasant events such as medical procedures, people are sometimes advised to distract themselves by thinking of something else. In this regard, the present findings imply that this strategy requires the distractive mental activity to be reasonably difficult. For instance, when participants were asked to imagine their neighbourhoods with high level of detail, they indeed paid less attention to unpleasant photographs as well as experienced less intense emotional reactions. When they merely thought of nonaffective features of affective images however, emotional attention was attenuated only modestly.
Why does a beautiful face stand out from a crowd? Or even a distant braking screech captures attention? A recent doctoral thesis suggests the reason may be faster processing of emotional information. The brain is equipped with various attention mechanisms for sorting out important information from potentially overwhelming sensory input. While top-down attention enables us to concentrate and bottom-up attention to remain vigilant for unexpected aspects of the environment, there is also a third system sensitive to emotional information. This affective attention is responsible for spotting opportunities such as a valuable mate or threats such as a traffic accident. Scientists do not fully comprehend however, how does competition between attention systems is resolved in the brain. As an example, consider a reader of an online news story whose eyes also capture a juicy headline at a sidebar. Sometimes affective attention succeeds in breaking the concentration on the story in favour of the emotional distraction. At other times however, top-down attention prevails and reading continues uninterrupted. In his thesis, Andero Uusberg investigated the idea that the competition between attentional systems changes across time. More specifically, affective attention may be faster off the mark while after about a third of a second however, top-down attention catches up and the subsequent focus is determined in co-operation. This framework explained several aspects of electrical brain activity measured while participants viewed emotionally evocative photographs. More broadly, different onsets can explain why safe stimuli such as a distant braking screech still captivates us – it takes a moment for the more context-aware top-down attention system to correct the early reaction of the more primitive affective attention. The thesis also has implications for everyday emotion regulation. To cope with unpleasant events such as medical procedures, people are sometimes advised to distract themselves by thinking of something else. In this regard, the present findings imply that this strategy requires the distractive mental activity to be reasonably difficult. For instance, when participants were asked to imagine their neighbourhoods with high level of detail, they indeed paid less attention to unpleasant photographs as well as experienced less intense emotional reactions. When they merely thought of nonaffective features of affective images however, emotional attention was attenuated only modestly.
Kirjeldus
Väitekirja elektrooniline versioon ei sisalda publikatsioone.
Märksõnad
psüühilised protsessid, emotsioonid, tähelepanu, elektroentsefalograafia, psychic processes, emotions, attention, electroencephalography