Hinnangud mõjutavad pupilli suurust: eesmärgi tüübi ja eesmärgiga ühilduvuse mõjud

This thesis attempted to investigate the effects of appraisal dimensions on pupillary movements. Three appraisal dimensions were under investigation: goal relevance, goal type and goal congruence. Three hypotheses were formulated. Pupil dilation a) differs in neutral and relevant events; b) depends differently on wins and losses; c) is affected by goal conduciveness and goal obstructiveness. A novel research paradigm was used to test these hypotheses. Instead of picture stimuli we relied on perceptually simple stimuli (Landolt circles) which were coupled with affective meaning. To that end we used the monetary incentive delay task (MID) where the stimuli were associated with three types of events: gains, losses, neutral. The conditioning in the experiment was successful. Pupil dilation showed a difference between neutral and relevant events. As predicted, the results confirmed that goal type has an effect on pupillary reactivity. To a degree goal conduciveness also demonstrated the pattern predicted, in that pupil reactivity changed, but only in approach conditions (conditions “you won” and “you did not win” differed significantly)

Afektiivsete tõlgenduste mõju tähelepanu kontrollile

Väitekirja elektrooniline versioon ei sisalda publikatsiooneMiks mõjutavad emotsionaalse sisuga olukorrad visuaalset tähelepanu? Miks on näiteks nii, et tänaval vihase näoga mööduja jääb väga kiiresti silma? Miks on ka nii, et ebameeldivas või ärevas olukorras kipub tähelepanu fookus olema ainult üksikutel detailidel ja kõrvalised detailid jäävad märkamata? Seni on emotsionaalse tähelepanu seletamisel rõhutatud emotsiooniga kaasnevat positiivset või negatiivset tunnet. Näiteks on rõhutatud seda, et negatiivsed stiimulid, nagu kellegi vihane nägu, haaravad tähelepanu just tänu nende negatiivsele sisule ja sellest tekitatud tundele. Tartu Ülikoolis tehtud doktoritöö kohaselt tuleks aga otsida seletust emotsionaalsetele sündmustele antud tõlgendustest, mis põhjustavad ja kujundavad emotsionaalset kogemust. Näiteks võib negatiivne emotsioon tekkida sellest, kui sündmus on oluline, aga ei ole kooskõlas hetke eesmärkidega. Sellised tõlgendusmehhanismid on sageli automaatsed ja toetuvad ajumehhanismidele, mis tegelevad pidevalt keskkonna hindamisega, arvestades seejuures meie enda hetke eesmärke. Doktoritöö uuringutulemused kinnitasid, et tähelepanu juhib just olukorra tajutud olulisus, mitte olukorra positiivsus või negatiivsus. Lisaks näitas doktoritöö, et mõningad emotsiooni efektid tähelepanu mehhanismidele ei pruugi olla kaugeltki nii selged kui varasem kirjandus on näidanud. Peale teoreetiliste edasiarenduste pakkusid esitatud uuringud ka metodoloogilisi täiendusi, nagu näiteks pupilli suuruse kasutamine visuaalse tähelepanu mõõdikuna. Doktoritöö tulemused arendasid edasi arusaamist emotsioonide ja tähelepanu seostest ja samuti pakkusid tulevastele uuringutele uusi lähenemisi.Why do emotional situations influence our visual attention? Why is it so that a passerby with an angry face quickly captures our attention? And why is it so that in an uncomfortable or anxious situation we tend to focus our attention on specific details and ignore other information? Previously, emotional attention has been explained mostly by emphasizing the subjective feeling caused by an emotion. According to this view, a negative stimulus, like an angry face, captures attention due to its negative nature and the negative feelings caused by it. In the current doctoral dissertation, it is suggested that the driving force behind emotional effects on attention is the appraisal process which is believed to cause and shape emotional experiences. For instance, negative emotion can arise by appraising an event as relevant and incongruent to our current goals. These appraisal mechanisms are described as fast and automatic, meaning that the brain automatically evaluates stimuli in accordance with the current goals. The findings confirmed that not the negative or positive feeling, but the subjective relevance attributed to a stimulus drives emotional attention. In addition, the findings showed that some emotional effects on attention are not as clear-cut as previously thought. Besides theoretical advancements, the studies presented in the dissertation provided methodological improvements, such as using pupil size as a measure of attentional processes. Overall, the findings developed our understanding of emotional effects on attention and provided some interesting future avenues for future research.https://www.ester.ee/record=b552399

EEG-alfa aktiivsuse ja afektiivsete seisundite seos tähelepanu ulatusega

Käesoleva uurimistöö eesmärgiks oli uurida tähelepanu ulatuse ja EEG-alfa vahelist seost. Tähelepanu ulatust mõõdeti globaalse-lokaalse taju ülesandega. Püstitati hüpotees, et kitsama tähelepanu fookusega kaasneb suurem alfa võimsus. Hüpoteesi testimiseks kasutati kahte lähenemist. Uuriti, kas katseisiku alfa võimsus suureneb siis, kui ta valib lokaalseid stiimuleid. Analüüsid näitasid, et alfa võimsus on seotud sellega, kuidas katseisik vastas globaalse-lokaalse taju ülesandes, katseisikute alfa võimsus suurenes lokaalsete stiimulite eelistamisel. Järgmisena uuriti, kas afektiivne seisund, mis käitumisandmete põhjal ahendab tähelepanu, suurendab ka alfa võimsust. Analüüs andis vasturääkivaid tulemusi, hüpoteesi toetasid mingil määral ootuslikud seisundid.http://www.ester.ee/record=b4430745~S1*es

Corticotroph Aggressive Pituitary Tumors and Carcinomas Frequently Harbor ATRX Mutations

Context: Aggressive pituitary tumors (APTs) are characterized by unusually rapid growth and lack of response to standard treatment. About 1% to 2% develop metastases being classified as pituitary carcinomas (PCs). For unknown reasons, the corticotroph tumors are overrepresented among APTs and PCs. Mutations in the alpha thalassemia/mental retardation syndrome X-linked (ATRX) gene, regulating chromatin remodeling and telomere maintenance, have been implicated in the development of several cancer types, including neuroendocrine tumors. Objective: To study ATRX protein expression and mutational status of the ATRX gene in APTs and PCs. Design: We investigated ATRX protein expression by using immunohistochemistry in 30 APTs and 18 PCs, mostly of Pit-1 and T-Pit cell lineage. In tumors lacking ATRX immunolabeling, mutational status of the ATRX gene was explored. Results: Nine of the 48 tumors (19%) demonstrated lack of ATRX immunolabelling with a higher proportion in patients with PCs (5/18; 28%) than in those with APTs (4/30;13%). Lack of ATRX was most common in the corticotroph tumors, 7/22 (32%), versus tumors of the Pit-1 lineage, 2/24 (8%). Loss-of-function ATRX mutations were found in all 9 ATRX immunonegative cases: nonsense mutations (n = 4), frameshift deletions (n = 4), and large deletions affecting 22-28 of the 36 exons (n = 3). More than 1 ATRX gene defect was identified in 2 PCs. Conclusion: ATRX mutations occur in a subset of APTs and are more common in corticotroph tumors. The findings provide a rationale for performing ATRX immunohistochemistry to identify patients at risk of developing aggressive and potentially metastatic pituitary tumors.Peer reviewe

On the relationship between valence and arousal in samples across the globe

Affect is involved in many psychological phenomena, but a descriptive structure, long sought, has been elusive. Valence and arousal are fundamental, and a key question–the focus of the present study–is the relationship between them. Valence is sometimes thought to be independent of arousal, but, in some studies (representing too few societies in the world) arousal was found to vary with valence. One common finding is that arousal is lowest at neutral valence and increases with both positive and negative valence: a symmetric V-shaped relationship. In the study reported here of self-reported affect during a remembered moment (N = 8,590), we tested the valence-arousal relationship in 33 societies with 25 different languages. The two most common hypotheses in the literature–independence and a symmetric V-shaped relationship–were not supported. With data of all samples pooled, arousal increased with positive but not negative valence. Valence accounted for between 5% (Finland) and 43% (China Beijing) of the variance in arousal. Although there is evidence for a structural relationship between the two, there is also a large amount of variability in this relation