Neuroradiološki prikaz funkcijskih i strukturnih promjena mozga izazvanih stresom

master's thesis

• Title (english): Neuroradiological presentation of stress-induced functional and structural changes in the brain
• Author: Anton Jakovčić
• Mentor: Milan Radoš (mentor)
• Committee member: Marko Radoš (predsjednik povjerenstva)
• Committee member: Zdravko Petanjek (član povjerenstva)
• Committee member: Milan Radoš (član povjerenstva)
• Granter: University of Zagreb; School of Medicine; (Department of Radiology); Zagreb
• Defense date and country: 2022-09-02, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Clinical Medical Sciences; Radiology

Abstract

Neuroradiološke metode sastavni su dio istraživanja utjecaja stresa na mozak jer omogućavaju neinvazivno ispitivanje njegove strukture i funkcije. Pri istraživanju stresa neuroradiološkim metodama koriste se različiti eksperimentalni protokoli koji daju heterogene rezultate. Najčešće korišteni su vizualni i aritmetički zadaci poput stresa izazvanog personaliziranom pričom, stresa izazvan Stroop-ovim testom, stresa izazvanog javnim govorom, stresa izazvanog serijskim oduzimanjem te Montreal stres test. Usprkos vrlo raznolikom pristupu u navedenim studijama određene regije mozga pokazale su konzistentnost strukturalnih i funkcionalnih promjena što upućuje na njihovu važnu ulogu u patofiziologiji stresa. Rezultati brojnih studija pokazuju kako su strukturalni volumeni frontalnog režnja, hipokampusa, inzule smanjeni usred dugotrajne izloženosti stresu, dok su rezultati istraživanja strukturalnih promjena kod amigdale oprečna. Funkcionalne promijene u ispitanika s posttraumatski stresnim poremećajem govore u prilog povećanja aktivnosti amigdale i inzule i smanjenja aktivnosti struktura frontalnog režnja i hipokampusa. Aktivnost inzule se s vremenom smanjuje vjerojatno kao dio habituacije. Čini se da regije frontalnog režnja i hipokampusa imaju negativnu povratnu kontrolu na amigdalu kao dio neuronskog kruga regulacije odgovora na stres. Odgovor na stres je dinamički proces te je stoga sve više longitudinalnih studija koje bolje prate promijene prilikom utjecaja stresa na mozak. Nadalje, ispitivanje strukturalnih i funkcionalnih promjena na mozgu usred izloženosti stresu treba različiti na tri kategorije. Prva kategorija spada u kongenitalne predispozicije mozga usred koji on može biti otporan ili podložan stresu. Druga kategorija se odnosi na stečene promijene koje su se dogodile usred samog utjecaja stresa, a koji nisu doveli do patofizioloških promjena koje mogu uzrokovati bolest. I treća kategorija se odnosi na patofiziološke promijene uzrokovane stresom usred patoloških procesa tokom razvijene bolesti kao što je naprimjer posttraumatski stresni poremećaj. Važnost neuroradioloških metoda mogla bi biti sve veća u budućnosti za probir pojedinaca koji se prijavljuju za visokorizična zanimanja kao što su vojnici, policajci, kontrolori leta i vatrogasci. Isto tako ove metode potencijalno su korisne za praćenje terapije i kao dio treninga za povećanje otpornosti na stres.

Abstract (english)

Neuroradiological methods are an integral part in the field of stress research because they enable a noninvasive examination of the structure and function of the brain. Different approaches to experimental designes have so far yielded heterogenus results. Visual and arithemic tasks such as script-driven stress stimuli, Stroop colour-word interference task, public speech-induced stress, serial subtraction design, and Montreal imaging stress task are the most commonly used approaches. In spite of varied approaches in studies, certain regions of the brain showed consistency in structural and functional changes across different studies which points to their importance in pathophysiology of stress. Based on many research studies structural volumes of frontal lobe, hippocampus, insula are smaller under the prolonged influence of stress, while research regarding structural changes in amygdala provides conflicting results. Functional changes in examinees with posttraumatic stress disorder point in the direction of increased activity of amygdala and insula, and a decreased activity of frontal lobe and hippocampus. Activity of insula decreases with time, likely due to habituation. It seems like regions of frontal lobe and hippocampus have negative feedback control on amygdala as part of a neural circuit of response regulation to stress. Furthermore, response to stress is a dynamic process and there is a growing body of longitudinal studies that are more apt in deciphering the influence of stress on the brain. Also, structural and functional studies of the brain under the influence of stress can be divided into three categories. In the first category are the congenital predispositions that can lead to stress resiliance or stress suceptibility. Second category encompasses acquired changes under the influence of stress but they do not include pathophysiological changes and disease development. And third catogory describes pathophysiological changes after the full development of stress related diseases such as post-traumatic stress disease. The importance of neuroradiological methods may become even greater in the future, especially in screening of candidates applying for high-risk professions such as army, police, flight control, and firefighters, as well as for therapy surveilance and as part of a stress resiliance training.

• Keywords: Neuroradiološki prikaz; eksperimentalni protokol; strukturalne promijene; funkcionalne promijene; stres
• Keywords (english): Neuroimaging; experimental design; structural changes; functional changes; stress
• Language: croatian
• URN:NBN: urn:nbn:hr:105:738312
• Study programme: Title: Medicine; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: doktor/doktorica medicine (doktor/doktorica medicine)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-01-09 12:39:10