{"id":6287,"date":"2026-10-19T09:48:43","date_gmt":"2026-10-19T09:48:43","guid":{"rendered":"https:\/\/phd.hi.is\/doktorsvorn\/doktorsvorn-i-salfraedi-kristjan-helgi-hjartarson\/"},"modified":"2026-10-19T09:48:43","modified_gmt":"2026-10-19T09:48:43","slug":"doktorsvorn-i-salfraedi-kristjan-helgi-hjartarson","status":"publish","type":"phd_defence","link":"https:\/\/phd.hi.is\/en\/doktorsvorn\/doktorsvorn-i-salfraedi-kristjan-helgi-hjartarson\/","title":{"rendered":"Doktorsv\u00f6rn \u00ed s\u00e1lfr\u00e6\u00f0i – Kristj\u00e1n Helgi Hjartarson"},"content":{"rendered":"
\n
\n

Fimmtudaginn 23. j\u00fan\u00ed ver Kristj\u00e1n Helgi Hjartarson doktorsritger\u00f0 s\u00edna \u00ed s\u00e1lfr\u00e6\u00f0i vi\u00f0 S\u00e1lfr\u00e6\u00f0ideild H\u00e1sk\u00f3la \u00cdslands. Ritger\u00f0in ber heiti\u00f0: Sj\u00e1lfvirkni \u00feunglyndis\u00feanka \u00ed daglegu l\u00edfi. Ranns\u00f3knir \u00e1 vanabundnu e\u00f0li \u00feunglyndis\u00feanka \u00ed \u00fart\u00f6kum h\u00e1sk\u00f3lanema og f\u00f3lks me\u00f0 endurteki\u00f0 \u00feunglyndi. Inns\u00fdn \u00far snjalls\u00edmam\u00e6lingum. The Automaticity of Depressive Rumination. A Test of the Habitual Nature of Ruminative Thinking in Clinical and Non-clinical Samples. Insights From an Ecological Momentary Assessment Perspective.<\/strong><\/p>\n

Andm\u00e6lendur eru dr. Edward Watkins, pr\u00f3fessor vi\u00f0 H\u00e1sk\u00f3lann \u00ed Exeter, Bretlandi, og dr. Ernst Koster, pr\u00f3fessor vi\u00f0 Ghent University \u00ed Belg\u00edu.<\/p>\n

Umsj\u00f3narkennari og lei\u00f0beinandi var Ragnar P\u00e9tur \u00d3lafsson, pr\u00f3fessor. A\u00f0rir \u00ed doktorsnefnd voru \u00cdvar Snorrason, kl\u00edn\u00edskur rannsakandi, og Laura F. Bringmann, a\u00f0sto\u00f0arpr\u00f3fessor vi\u00f0 University of Groningen.<\/p>\n

Ur\u00f0ur Njar\u00f0v\u00edk, pr\u00f3fessor og deildarforseti S\u00e1lfr\u00e6\u00f0ideildar, stj\u00f3rnar ath\u00f6fninni sem fer fram \u00ed H\u00e1t\u00ed\u00f0asal H\u00e1sk\u00f3la \u00cdslands og hefst kl. 13:00.<\/p>\n

V\u00f6rninni ver\u00f0ur streymt:\u00a0https:\/\/livestream.com\/hi\/doktorsvornkristjanhelgihjartarson<\/a><\/p>\n

\u00c1grip<\/strong><\/p>\n

\u00deunglyndi (major depression) er algengasta ge\u00f0r\u00f6skunin og \u00ed dag talin vera helsta ors\u00f6kin fyrir \u00f6rorku \u00e1 heimsv\u00edsu. \u00deunglyndis\u00feankar eru flokkur neikv\u00e6\u00f0ra hugsana sem fela \u00ed s\u00e9r a\u00f0 dvelja lengi og endurteki\u00f0 \u00ed hugsanlegri merkingu, ors\u00f6k og aflei\u00f0ingum eigin tilfinninga og vi\u00f0brag\u00f0a. N\u00fdlegar kenningar gera r\u00e1\u00f0 fyrir a\u00f0 \u00feunglyndis\u00feankar s\u00e9u hugr\u00e6nn vani sem virkjast sj\u00e1lfkrafa, \u00e1n \u00e6tlunar e\u00f0a vitundar, sem vi\u00f0brag\u00f0 vi\u00f0 versnandi l\u00ed\u00f0an.<\/p>\n

Meginmarkmi\u00f0 ranns\u00f3knarverkefnisins var a\u00f0 beita tilraunaverkefnum og n\u00fdst\u00e1rlegri snjalls\u00edmam\u00e6lingu (ecological momentary assessment) til a\u00f0 fanga samspil l\u00ed\u00f0anar og \u00feunglyndis\u00feanka \u00ed daglegu l\u00edfi f\u00f3lks. \u00derj\u00e1r ranns\u00f3knir voru ger\u00f0ar til a\u00f0 meta tilg\u00e1tur um a) \u00e1hrif stundar-sveiflna (momentary fluctuations) \u00ed neikv\u00e6\u00f0ri l\u00ed\u00f0an \u00e1 \u00feunglyndis\u00feanka, b) vanabundna eiginleika \u00e1 samspil l\u00ed\u00f0anar og \u00feunglyndis\u00feanka og c) hvort aukin tilhneiging til \u00feunglyndis\u00feanka \u00ed kj\u00f6lfar vanl\u00ed\u00f0anar tengist frekari \u00e1h\u00e6ttu \u00e1 \u00feunglyndi.<\/p>\n

Helstu ni\u00f0urst\u00f6\u00f0ur s\u00fdndu a\u00f0 stundarsveiflur \u00ed neikv\u00e6\u00f0ri (h\u00e6kka\u00f0ri) og j\u00e1kv\u00e6\u00f0ri (l\u00e6kka\u00f0ri) l\u00ed\u00f0an sp\u00e1\u00f0u markt\u00e6kt fyrir um aukna \u00feunglyndis\u00feanka fr\u00e1 einni stund til \u00feeirrar n\u00e6stu. Sterkari p\u00f6run stundarsveiflna \u00ed l\u00ed\u00f0an og \u00feunglyndis\u00fe\u00f6nkum s\u00e1st hj\u00e1 \u00feeim sem greindu fr\u00e1 r\u00edkari vanabundnum eiginleikum hugsunar. N\u00e1nari athugun s\u00fdndi a\u00f0 l\u00ed\u00f0an kveikti einungis \u00e1 \u00feunglyndis\u00fe\u00f6nkum hj\u00e1 \u00fe\u00e1tttakendum me\u00f0 fyrri s\u00f6gu um endurteki\u00f0 \u00feunglyndi en ekki hj\u00e1 heilbrig\u00f0u f\u00f3lki me\u00f0 enga fyrri ge\u00f0s\u00f6gu. Hj\u00e1 \u00fe\u00e1tttakendum me\u00f0 fyrri s\u00f6gu um \u00feunglyndi sp\u00e1\u00f0u vanabundnir eiginleikar hugsunar fyrir um hversu miki\u00f0 stundarsveiflur \u00ed l\u00ed\u00f0an kveiktu \u00e1 \u00feunglyndis\u00fe\u00f6nkum yfir t\u00edma, og var s\u00e9rstaklega \u00e1berandi hj\u00e1 \u00feeim sem h\u00f6f\u00f0u s\u00f6gu um streituvaldandi atbur\u00f0i \u00ed \u00e6sku. Ni\u00f0urst\u00f6\u00f0urnar gefa til kynna a\u00f0 sterkari vanabundin t\u00edmap\u00f6run \u00e1 milli l\u00ed\u00f0anar og \u00feunglyndis\u00feanka geti veri\u00f0 n\u00e6mis\u00fe\u00e1ttur fyrir \u00feunglyndi. Jafnframt a\u00f0 hef\u00f0bundnir sj\u00e1lfsmatskvar\u00f0ar \u00e1 t\u00ed\u00f0ni \u00feunglyndis\u00feanka n\u00e1i ekki utan um samspil l\u00ed\u00f0anar og \u00feunglyndis\u00feanka og \u00fev\u00ed \u00feurfi ranns\u00f3knir a\u00f0 leggja r\u00edkari \u00e1herslu \u00e1 a\u00f0ra eiginleika vanabundinnar hugsunar \u00ed ranns\u00f3knum \u00e1h\u00e6ttu\u00fe\u00e1ttum \u00feunglyndis. \u00cd framt\u00ed\u00f0inni g\u00e6tu snjalls\u00edmam\u00e6lingar reynst vel til a\u00f0 pr\u00f3fa tilg\u00e1tur um vanabundi\u00f0 e\u00f0li \u00feunglyndis\u00feanka, sem hinga\u00f0 til hefur tekist illa a\u00f0 leggja pr\u00f3fstein v\u00edsindanna \u00e1.<\/p>\n

English abstract<\/strong><\/p>\n

Major depression is the most common psychiatric disorder, associated with the highest disease burden worldwide when it comes to years lost to disability. Efforts to identify indicators of depression risk have strongly implicated depressive rumination, a negative thinking style characterized by repetitive and passive thoughts about the causes, meanings, and consequences of one’s feelings and distress. An increasingly popular theoretical perspective posits that over time depressive rumination becomes a mental habit that is initiated automatically without conscious awareness or intent in response to downward shifts in mood, making it persistent and difficult to control.<\/p>\n

The aim of the current research project was to utilize a combination of experimental and novel mobile in-the-moment assessment strategies to better understand the dynamic interplay between mood and ruminative thinking and its habitual characteristics. Three studies were designed to test specific hypotheses involving: a) effects that fluctuations in mood have on subsequent ruminative thinking, b) the degree to which habitual characteristics of negative thinking predict such mood-reactive rumination, and c) whether mood-reactive rumination varies according to the depression-risk spectrum in line with theoretical accounts of depression vulnerability.<\/p>\n

The main results showed that momentary fluctuations in negative (increased) and positive (decreased) affect was prospectively associated with greater rumination over time. The degree to which affect triggered a subsequent ruminative response was moderated by habitual characteristics of negative thinking in a theoretically consistent way. Further investigation showed that this pattern of mood-reactive rumination was only observed in formerly depressed participants but not in healthy never-depressed participants. In formerly depressed participants, habitual characteristics of negative thinking were associated with greater mood-reactivity of rumination, particularly among those with a history of early-life stress.<\/p>\n

The current thesis suggests ways depression vulnerability may emerge as a dynamic relationship between negative affect and rumination across time, not captured by traditional trait measures of rumination frequency. Ecological momentary assessment may be a valuable measurement paradigm to test predictions derived from habit-accounts of depressive rumination, that have rarely been investigated until now, and might provide new insights into research on depression risk.\u00a0<\/p>\n

Um doktorsefni\u00f0<\/strong><\/p>\n

Kristj\u00e1n Helgi Hjartarson er f\u00e6ddur \u00e1ri\u00f0 1990 \u00ed Reykjav\u00edk. Hann lauk st\u00fadentspr\u00f3fi af hug- og f\u00e9lagsv\u00edsindabraut fr\u00e1 Framhaldssk\u00f3la Austur-Skaftafellss\u00fdslu \u00e1ri\u00f0 2010, BS-pr\u00f3fi \u00ed s\u00e1lfr\u00e6\u00f0i fr\u00e1 H\u00e1sk\u00f3la \u00cdslands \u00e1ri\u00f0 2015 og meistarapr\u00f3fi \u00ed kl\u00edn\u00edskri s\u00e1lfr\u00e6\u00f0i fr\u00e1 H\u00e1sk\u00f3la \u00cdslands \u00e1ri\u00f0 2017. Samhli\u00f0a doktorsn\u00e1minu sinnti Kristj\u00e1n kennslu vi\u00f0 H\u00e1sk\u00f3la \u00cdslands, en hann starfar n\u00fa sem s\u00e1lfr\u00e6\u00f0ingur hj\u00e1 Kv\u00ed\u00f0ame\u00f0fer\u00f0arst\u00f6\u00f0inni \u00ed Reykjav\u00edk. Foreldrar Kristj\u00e1ns eru Ragnhildur Magn\u00fasd\u00f3ttir og Sigur\u00f0ur Hj\u00f6rtur Kristj\u00e1nsson. Maki Kristj\u00e1ns er \u00de\u00f3rhildur \u00d3lafsd\u00f3ttir s\u00e1lfr\u00e6\u00f0ingur og eiga \u00feau b\u00f6rnin Hj\u00f6rt \u00d3la, Kristin Hl\u00edfar og Ragnar Darra.<\/p>\n

\u00a0<\/p>\n<\/div><\/div>","protected":false},"featured_media":5146,"template":"","meta":{"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","ast-disable-related-posts":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"_phd_date_start":"2022-06-23T13:00:00+00:00","_phd_date_end":"2022-06-23T16:00:00+00:00","_phd_location":"A\u00f0albygging H\u00e1t\u00ed\u00f0asalur","_phd_admission":"A\u00f0gangur \u00f3keypis","_phd_thesis_title":"Sj\u00e1lfvirkni \u00feunglyndis\u00feanka \u00ed daglegu l\u00edfi. Ranns\u00f3knir \u00e1 vanabundnu e\u00f0li \u00feunglyndis\u00feanka \u00ed \u00fart\u00f6kum h\u00e1sk\u00f3lanema og f\u00f3lks me\u00f0 endurteki\u00f0 \u00feunglyndi. Inns\u00fdn \u00far snjalls\u00edmam\u00e6lingum. The Automaticity of Depressive Rumination. A Test of the Habitual Nature of Ruminative Thinking in Clinical and Non-clinical Samples. Insights From an Ecological Momentary Assessment Perspective","_phd_source_url":"https:\/\/gamli.hi.is\/vidburdir\/doktorsvorn_i_salfraedi_kristjan_helgi_hjartarson","_phd_source_node_id":"384651","_phd_source_type":"vidburdir","_phd_member_id":816,"footnotes":""},"phd_school":[60,75],"phd_discipline":[76],"class_list":["post-6287","phd_defence","type-phd_defence","status-publish","has-post-thumbnail","hentry","phd_school-heilbrigdisvisindasvid","phd_school-salfraedideild","phd_discipline-phd-i-salfraedi"],"_links":{"self":[{"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_defence\/6287","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_defence"}],"about":[{"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/types\/phd_defence"}],"version-history":[{"count":0,"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_defence\/6287\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/media\/5146"}],"wp:attachment":[{"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/media?parent=6287"}],"wp:term":[{"taxonomy":"phd_school","embeddable":true,"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_school?post=6287"},{"taxonomy":"phd_discipline","embeddable":true,"href":"https:\/\/phd.hi.is\/en\/wp-json\/wp\/v2\/phd_discipline?post=6287"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}