Thesis (Ph. D.)--University of Oregon, 2008. / Typescript. Includes vita and abstract. Includes bibliographical references (leaves 188-219). Also available online in ProQuest, free to University of Oregon users.

Au sein du circuit cortico-limbique, des régions complémentaires seraient impliquées soit dans l’évaluation soit dans la régulation des états affectifs. Cependant, la contribution respective de ces mécanismes «bottom-up» et «top-down» lors du traitement émotionnel reste à clarifier. Premièrement, nous avons validé un nouveau paradigme d’IRMf conçu pour dissocier les composants du circuit cortico-limbique, c.-à-d. le circuit dorsal cognitif entrecroisé avec le circuit ventral affectif. Nous avons trouvé que l’amygdale et ses connexions avec le circuit dorsal étaient engagées par le traitement émotionnel bottom-up. Le cortex cingulaire antérieur (CCA) dorsal et ses connexions avec le cortex préfrontal dorso-latéral (CPFDL) et l’amygdale étaient recrutés par la résolution top-down du conflit émotionnel. Le CPFDL et ses connexions avec le CCA dorsal étaient engagés par le contrôle attentionnel top-down. Puis, nous avons examiné l’impact de l’anxiété sur le circuit. Nous avons montré qu’une forte anxiété était associée à une activation plus importante du CCA en réponse au conflit émotionnel mais à une connectivité réduite entre CCA et CPFL. Enfin, nous avons examiné la variation d’activité et de connectivité fonctionnelle chez des patients schizophrènes. Chez les patients comparativement aux témoins, les processus bottom-up étaient associés à une interaction réduite entre l’amygdale et le CCA ventral et dorsal ainsi que le CPFDL. La résolution du conflit émotionnel entraînait une plus forte connectivité entre CCA dorsal et CCA ventral ainsi que le CPFDL. L’augmentation du contrôle attentionnel provoquait une connectivité plus importante entre le CPFDL et le CCA ventral. / Within the cortico-limbic circuit, complementary regions are believed to be involved in either the appraisal or the regulation of affective state. However, the respective contribution of these bottom-up and top-down mechanisms during emotion processing remains to be clarified. First, we validated a new fMRI paradigm designed to dissociate the components of the cortico-limbic circuit, that is, the dorsal cognitive circuit intertwined with the ventral affective circuit. We found that the amygdala and its connections to the dorsal circuit was engaged by bottom-up emotional processing. The dorsal anterior cingulate cortex (ACC) and its connections to the dorsolateral prefrontal cortex (DLPFC) and amygdala, was recruited by top-down resolution of emotional conflict. The DLPFC and its connections to dorsal ACC was engaged by top-down attentional control. Secondly, we investigated the impact of anxiety on the circuit. We demonstrated that higher levels of anxiety were associated with stronger conflict-related activation in ACC but with reduced connectivity between ACC and LPFC. Finally, we examined the variation in functional activity and connectivity in schizophrenia patients. In patients compared to controls, bottom-up processes were associated with reduced functional interaction between the amygdala and both dorsal and ventral ACC as well as DLPFC. Top-down resolution of emotional conflict led to stronger functional connectivity between the dorsal ACC and both ventral parts of ACC and DLPFC. Increased top-down attentional control caused higher functional coupling between the DLPFC and ventral ACC.

Stress and limbic iritability in depression and alcohol dependency Denisa Jasová Abstract Depressive disorders and alcohol dependency recently present epidemiologically most significant psychiatric disorders. According to current research both diseases are multifactorial, mainly represented by genetic and environmental conditions. Several recent research studies are mainly focused on social factors related to stress and traumatic events such as neglect, deprivation, verbal, emotional, physical and sexual abuse, bullying and others. Important feature of these pathological conditions present disbalance between excitatory and inhibitory systems. In this context in affective disorders as well as in alcohol dependency these inhibitory deficits are represented by increased sensitivity and excitability of the limbic system called limbic irritability. Several studies suggested that these pathological changes may be described using the kindling model that potentially may explain limbic changes similar to temporal lobe epilepsy which may produce affective, cognitive and psychosensory symptoms but without typical changes that occur in neurologically diagnosed epilepsy. Following these findings significant correlations between depression and limbic irritability and between limbic irritability and alcohol craving have...

Despite extensive research in the field of aging neuroscience, it still remains unclear whether age related cortical changes can be detected in different functional networks of younger adults and whether these networks respond identically to healthy aging. We collected high-resolution brain anatomical data from 56 young healthy adults (mean age = 30.8 +/- 8.1 years, 29 males). We performed whole brain parcellation into seven functional networks, including visual, somatomotor, dorsal attention, ventral attention, limbic, frontoparietal and default mode networks. We estimated intracranial volume (ICV) and averaged cortical thickness (CT), cortical surface area (CSA) and cortical volume (CV) over each hemisphere as well as for each network. Averaged cortical measures over each hemisphere, especially CT and CV, were significantly lower in older individuals compared to younger ones (one-way ANOVA, p < 0.05, corrected for multiple comparisons). There were negative correlations between age and averaged CT and CV over each hemisphere (p < 0.05, corrected for multiple comparisons) as well as between age and ICV (p = 0.05). Network level analysis showed that age was negatively correlated with CT for all functional networks (p < 0.05, corrected for multiple comparisons), apart from the limbic network. While age was unrelated to CSA, it was negatively correlated with CV across several functional networks (p < 0.05, corrected for multiple comparisons). We also showed positive associations between CV and CT and between CV and CSA for all networks (p < 0.05, corrected for multiple comparisons). We interpret the lack of association between age and CT of the limbic network as evidence that the limbic system may be particularly resistant to age-related declines during this period of life, whereas the significant age-related declines in averaged CT over each hemisphere as well as in all other six networks suggests that CT may serve as a reliable biomarker to capture the effect of normal aging. Due to the simultaneous dependence of CV on CT and CSA, CV was unable to identify such effects of normal aging consistently for the other six networks, but there were negative associations observed between age and averaged CV over each hemisphere as well as between age and ICV. Our findings suggest that the identification of early cortical changes within various functional networks during normal aging might be useful for predicting the effect of aging on the efficiency of functional performance even during early adulthood.

Tinnitus is a phantom auditory perception characterized by a ringing sound in either one or both ears. It is a common disorder most often associated with hearing loss and can have a severe impact on a person's quality of life. There is currently no cure and no efficient therapeutic options. There is little known about the neural mechanisms underlying the generation of tinnitus but a better understanding of its neural basis could greatly benefit the development of efficient treatment methods. This literature study aims to explore the neural mechanisms of tinnitus in terms of generation, perpetuation, and perception. Cochlear dysfunction, changes in neuronal firing rates and oscillatory properties, hyperactivity, lack of inhibitory activity and plasticity in auditory-limbic structures have been associated with tinnitus and may be a part of a crossmodal network involved in generating, perpetuating and perceiving tinnitus, through maladaptive CNS plasticity. New developing treatment methods aim to modulate and re-route tinnitus-related plasticity, however, this leads to treatment difficulties due to the crossmodal nature of the tinnitus pathophysiology. These difficulties will be further examined in the discussion.

v anglickém jazyce Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biological and Medical Sciences Author: Bc. Aneta Capranicová Title of diploma thesis: Osteoporosis, climacteric syndrome and signs of the temporolimbic dysfunction Objective of the thesis: The aim of the diploma thesis was to find out whether there will appear temporolimbic dysfunctions in women attending the osteoporotic clinic at the Faculty Hospital in Hradec Králové and compare their results with the results of a healthy population. Methods: Two standardized questionnaires - CSPI and LSCL-33 - were used to assess the occurrence of epileptic spectrum disorders. The Microsoft Office Excel was used to process the results. Results: It was found that the women population reaches score points corresponding to the healthy population. In the CSPI questionnaire, the average value was 7.6 and for the LSCL-33 5.5 points. From these results it can be assumed that osteoporosis and climacteric syndrome does not affect the occurrence of epileptic spectrum disorders. To confirm the results, I would recommend the study to be repeated in a group with a larger number of respondents. For comparison with gamblers or smokers, both groups show a higher incidence of epileptic spectrum disorders than the group of women...

Stress and limbic iritability in depression and alcohol dependency Denisa Jasová Abstract Depressive disorders and alcohol dependency recently present epidemiologically most significant psychiatric disorders. According to current research both diseases are multifactorial, mainly represented by genetic and environmental conditions. Several recent research studies are mainly focused on social factors related to stress and traumatic events such as neglect, deprivation, verbal, emotional, physical and sexual abuse, bullying and others. Important feature of these pathological conditions present disbalance between excitatory and inhibitory systems. In this context in affective disorders as well as in alcohol dependency these inhibitory deficits are represented by increased sensitivity and excitability of the limbic system called limbic irritability. Several studies suggested that these pathological changes may be described using the kindling model that potentially may explain limbic changes similar to temporal lobe epilepsy which may produce affective, cognitive and psychosensory symptoms but without typical changes that occur in neurologically diagnosed epilepsy. Following these findings significant correlations between depression and limbic irritability and between limbic irritability and alcohol craving have...

Autism spectrum disorders (ASDs) are characterized by phenotypic and genetic heterogeneity. Our analysis of functional networks perturbed in ASD suggests that both truncating and non-truncating de novo mutations contribute to autism. Moreover, we find that truncating mutations affecting the same exon lead to strikingly similar intellectual phenotypes in unrelated ASD probands and propose that exons, rather than genes, represent a unit of effective phenotypic impact for truncating mutations in autism. The phenotypic effects are likely mediated by nonsense-mediated decay of splicing isoforms and similar patterns may be observed in other genetic disorders. While multiple cell types and brain areas are affected, the impact of ASD mutations converge on a strongly interconnected system of neural structures that involve basal ganglia loops and the limbic system. We observe that distant projections constitute a disproportionately large fraction of the network composition, suggesting that the integration of diverse brain regions is a key property of the neural circuit. We demonstrate that individual de novo mutations impact several disparate components of the network and may further explain the phenotypic variability. Overall, our study presents a method that, to our knowledge, is the first unbiased approach using genetic variants to comprehensively discover and identify the neural circuitry affected in a psychiatric disorder.

No description available.

Musical emotions,such as happiness and sadness,have been investigated using instrumental music devoid of linguistic content. However, pop and rock, the most common musical genres, utilize lyrics for conveying emotions. Using participants’ self-selected musical excerpts, we studied their behavior and brain responses to elucidate how lyrics interact with musical emotion processing, as reflected by emotion recognition and activation of limbic areas involved in affective experience. We extracted samples from subjects’ selections of sad and happy pieces and sorted them according to the presence of lyrics. Acoustic feature analysis showed that music with lyrics differed from music without lyrics in spectral centroid, a feature related toperceptual brightness,whereassadmusicwithlyricsdidnotdivergefromhappymusicwithoutlyrics,indicatingtheroleofotherfactorsinemotionclassification.Behavioralratingsrevealedthathappymusicwithoutlyricsinducedstrongerpositiveemotionsthanhappymusicwithlyrics.Wealsoacquiredfunctionalmagneticres-onanceimagingdatawhilesubjectsperformedaffectivetasksregardingthemusic.First,usingecologicalandacousticallyvariablestimuli,webroadenedpreviousfindingsaboutthebrainprocessingofmusicalemotionsandofsongsversusinstrumentalmusic.Addition-ally,contrastsbetweensadmusicwithversuswithoutlyricsrecruitedtheparahippocampalgyrus,theamygdala,theclaustrum,theputamen,theprecentralgyrus,themedialandinfe-riorfrontalgyri(includingBroca’sarea),andtheauditorycortex,whilethereversecontrastproducednoactivations.Happymusicwithoutlyricsactivatedstructuresofthelimbicsys-temandtherightparsopercularisoftheinferiorfrontalgyrus,whereasauditoryregionsalonerespondedtohappymusicwithlyrics.Thesefindingspointtotheroleofacousticcuesfortheexperienceofhappinessinmusicandtotheimportanceoflyricsforsadmusicalemotions.