| 1. |
- Almby, Kristina E., et al.
(författare)
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Effects of Gastric Bypass Surgery on the Brain : Simultaneous Assessment of Glucose Uptake, Blood Flow, Neural Activity, and Cognitive Function During Normo- and Hypoglycemia
- 2021
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Ingår i: Diabetes. - : American Diabetes Association. - 0012-1797 .- 1939-327X. ; 70:6, s. 1265-1277
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Tidskriftsartikel (refereegranskat)abstract
- While Roux-en-Y gastric bypass (RYGB) surgery in obese individuals typically improves glycemic control and prevents diabetes, it also frequently causes asymptomatic hypoglycemia. Previous work showed attenuated counterregulatory responses following RYGB. The underlying mechanisms as well as the clinical consequences are unclear. In this study, 11 subjects without diabetes with severe obesity were investigated pre- and post-RYGB during hyperinsulinemic normo-hypoglycemic clamps. Assessments were made of hormones, cognitive function, cerebral blood flow by arterial spin labeling, brain glucose metabolism by F-18-fluorodeoxyglucose (FDG) positron emission tomography, and activation of brain networks by functional MRI. Post- versus presurgery, we found a general increase of cerebral blood flow but a decrease of total brain FDG uptake during normoglycemia. During hypoglycemia, there was a marked increase in total brain FDG uptake, and this was similar for post- and presurgery, whereas hypothalamic FDG uptake was reduced during hypoglycemia. During hypoglycemia, attenuated responses of counterregulatory hormones and improvements in cognitive function were seen postsurgery. In early hypoglycemia, there was increased activation post- versus presurgery of neural networks in brain regions implicated in glucose regulation, such as the thalamus and hypothalamus. The results suggest adaptive responses of the brain that contribute to lowering of glycemia following RYGB, and the underlying mechanisms should be further elucidated.
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| 2. |
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| 3. |
- Bannbers, Elin, 1984-, et al.
(författare)
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Prefrontal activity during response inhibition decreases over time in the postpartum period
- 2013
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Ingår i: Behavioural Brain Research. - : Elsevier BV. - 0166-4328 .- 1872-7549. ; 241, s. 132-138
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Tidskriftsartikel (refereegranskat)abstract
- The postpartum period is characterized by complex hormonal changes, but human imaging studies in the postpartum period have thus far predominantly focused on the neural correlates of maternal behavior or postpartum depression, whereas longitudinal studies on neural correlates of cognitive function across the postpartum period in healthy women are lacking. The aim of this study was to longitudinally examine response inhibition, as a measure of executive function, during the postpartum period and its neural correlates in healthy postpartum women and non-postpartum controls. Thirteen healthy postpartum women underwent event-related functional magnetic resonance imaging while performing a Go/NoGo task. The first assessment was made within 48 h of delivery, and the second at 4-7 weeks postpartum. In addition, 13 healthy women examined twice during the menstrual cycle were included as non-postpartum controls. In postpartum women region of interest analyses revealed task-related decreased activations in the right inferior frontal gyrus, right anterior cingulate, and bilateral precentral gyri at the late postpartum assessment. Generally, postpartum women displayed lower activity during response inhibition in the bilateral inferior frontal gyri and precentral gyri compared to non-postpartum controls. No differences in performance on the Go/NoGo task were found between time-points or between groups. In conclusion, this study has discovered that brain activity in prefrontal areas during a response inhibition task decreases throughout the course of the first postpartum weeks and is lower than in non-postpartum controls. Further studies on the normal adaptive brain activity changes that occur during the postpartum period are warranted. (C) 2012 Elsevier B.V. All rights reserved.
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| 4. |
- Bannbers, Elin, et al.
(författare)
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The effect of premenstrual dysphoric disorder and menstrual cycle phase on brain activity during response inhibition
- 2012
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Ingår i: Journal of Affective Disorders. - : Elsevier BV. - 0165-0327 .- 1573-2517. ; 142:1-3, s. 347-350
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:Premenstrual dysphoric disorder (PMDD) has generally not been associated with impulsive behavior. However, some studies suggest that women with PMDD have higher impulsivity scores than healthy controls and that brain activity during response inhibition may vary across the menstrual cycle. Therefore, our aim was to unravel potentially important cognitive aspects of PMDD by investigating brain activity during response inhibition in women with PMDD and healthy controls in relation to menstrual cycle phase.METHODS:Fourteen PMDD patients and 13 healthy controls performed a Go/NoGo task to measure brain activity during response inhibition by use of event-related functional magnetic resonance imaging.RESULTS:Women with PMDD displayed decreased activity during both menstrual cycle phases compared to healthy controls in several task-related parietal areas. A significant group by phase interactions was found in the left insula, driven by enhanced activity among healthy controls in the follicular phase and by enhanced insula activity during the luteal phase among PMDD patients.LIMITATIONS:The limitations of the present study are the relatively limited sample size, the relatively small number of NoGo trials and the lack of a baseline contrast for the NoGo trials.CONCLUSIONS:During response inhibition women with PMDD have reduced activity in areas associated with attention and motor function which is unrelated to menstrual cycle phase. Insular cortex activity, involved in both affective and cognitive processing, was significantly activated during the luteal phase among PMDD women. These findings are relevant for the understanding of how ovarian steroids influence mood symptoms in women.
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| 5. |
- Comasco, Erika, et al.
(författare)
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Emotional fronto-cingulate cortex activation and brain derived neurotrophic factor polymorphism in premenstrual dysphoric disorder
- 2014
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Ingår i: Human Brain Mapping. - : Wiley. - 1065-9471 .- 1097-0193. ; 35:9, s. 4450-4458
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Tidskriftsartikel (refereegranskat)abstract
- Premenstrual dysphoric disorder (PMDD) is the prototypical sex-specific disorder in which symptom onset and offset require a particular hormonal milieu and for which there is moderate heritability. The present study investigated brain emotion processing in PMDD and healthy controls, as well as functional polymorphisms in two candidate genes for PMDD, the serotonin transporter (5-HTT) and brain derived neurotrophic factor (BDNF). The 5-HTT linked polymorphic region (5-HTTLPR) and BDNF Val66Met polymorphisms were genotyped in 31 patients with PMDD and 31 healthy controls. A subset of 16 patients and 15 controls participated in two functional magnetic resonance imaging-sessions performing an emotion processing task; once in the mid-follicular, and once in the late luteal phase which corresponds with maximum severity of mood symptoms. Genotypes were not directly associated with PMDD. A main effect of group was found in the whole brain analysis, with patients having lower activation of the pre-genual anterior cingulate and ventro-medial prefrontal cortex, independent of menstrual cycle phase. Post-hoc functional ROI analyses in the fronto-cingulate cluster showed no effect of 5-HTTLPR genotype but a genotype-by-group-by-phase interaction effect of BDNF Val66Met. Women with PMDD who were carriers of the Met-allele had lower fronto-cingulate cortex activation in the luteal phase compared to Met-allele carrying controls. The results provide suggestive evidence of impaired emotion-induced fronto-cingulate cortex activation in PMDD patients. Although limited by a small sample, the potential influence of BDNF Val66Met in PMDD is in line with preclinical findings. Hum Brain Mapp, 2014.
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| 6. |
- Engman, Jonas, et al.
(författare)
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Hormonal Cycle and Contraceptive Effects on Amygdala and Salience Resting-State Networks in Women with Previous Affective Side Effects on the Pill.
- 2018
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Ingår i: Neuropsychopharmacology. - : Springer Science and Business Media LLC. - 0893-133X .- 1740-634X. ; 43:3, s. 555-563
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Tidskriftsartikel (refereegranskat)abstract
- The mechanisms linking ovarian hormones to negative affect are poorly characterized, but important clues may come from the examination of the brain's intrinsic organization. Here, we studied the effects of both the menstrual cycle and oral contraceptives (OCs) on amygdala and salience network resting-state functional connectivity using a double-blind, randomized, and placebo-controlled design. Hormone levels, depressive symptoms, and resting-state functional connectivity were measured in 35 healthy women (24.9±4.2 years) who had previously experienced OC-related negative affect. All participants were examined in the follicular phase of a baseline cycle and in the third week of the subsequent cycle during treatment with either a combined OC (30 μg ethinyl estradiol/0.15 mg levonorgestrel) or placebo. The latter time point targeted the midluteal phase in placebo users and steady-state ethinyl estradiol and levonorgestrel concentrations in OC users. Amygdala and salience network connectivity generally increased with both higher endogenous and synthetic hormone levels, although amygdala-parietal cortical connectivity decreased in OC users. When in the luteal phase, the naturally cycling placebo users demonstrated higher connectivity in both networks compared with the women receiving OCs. Our results support a causal link between the exogenous administration of synthetic hormones and amygdala and salience network connectivity. Furthermore, they suggest a similar, potentially stronger, association between the natural hormonal variations across the menstrual cycle and intrinsic network connectivity.
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| 7. |
- Gingnell, Malin, 1982-, et al.
(författare)
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Emotional anticipation after delivery - a longitudinal neuroimaging study of the postpartum period
- 2017
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Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 7
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Tidskriftsartikel (refereegranskat)abstract
- Neuroimaging research has begun to unveil the mechanisms behind emotion processing during the postpartum period, which, in turn, may be of relevance for the development of postpartum depression. The present study sought to longitudinally investigate the neural correlates of emotion anticipation during the postpartum period in healthy women. Functional magnetic resonance imaging was employed to measure the blood oxygen level-dependent signal in the brain in response to anticipation of negative emotional stimuli and during processing of images with positive or negative valence. The participating women were scanned twice: the first scan occurred during the first 48 hours after delivery, and the second was performed 4-6 weeks after delivery. The early postpartum period was characterized by higher anterior cingulate cortex reactivity during anticipation of negative emotional stimuli than the late postpartum period. This was accompanied by a negative relationship with insular reactivity during the early postpartum period and a trend towards an increase in insular reactivity in the late postpartum period. Thus, during the first four weeks of the postpartum period, a diminished top-down regulatory feedback on emotion-related areas of the brain was noted. This finding suggests a physiologically important adaptation during the healthy postpartum period.
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| 8. |
- Gingnell, Malin, et al.
(författare)
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Menstrual cycle effects on amygdala reactivity to emotional stimulation in premenstrual dysphoric disorder
- 2012
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Ingår i: Hormones and Behavior. - : Elsevier BV. - 0018-506X .- 1095-6867. ; 62:4, s. 400-406
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Tidskriftsartikel (refereegranskat)abstract
- Premenstrual dysphoric disorder (PMDD) with luteal phase related anxiety and mood swings compromise quality of life in around 4% of reproductive women. While anxiety is related to amygdala function, prior studies on amygdala reactivity both in healthy controls and women with PMDD are inconsistent with respect to menstrual cycle effects. Here women with PMDD and healthy controls were exposed to emotional faces during the mid-follicular and late luteal phase, and mean blood-oxygen-level dependence (BOLD) signal changes in the amygdala were determined with functional magnetic resonance imaging (fMRI). Women with PMDD had enhanced bilateral amygdala reactivity in the follicular phase in comparison with healthy controls, but there was no difference between groups during the luteal phase. In contrast, healthy controls displayed higher left amygdala reactivity in the luteal than in their follicular phase. However, among women with PMDD follicular phase progesterone serum concentrations were positively correlated with bilateral amygdala reactivity while depression scores were positively correlated with right amygdala reactivity in the luteal phase. In addition, women with PMDD and high scores on trait anxiety had increased right amygdala reactivity in the luteal as compared to the follicular phase. Finally, amygdala reactivity was more prone to habituation in women with PMDD, as they had enhanced amygdala reactivity in comparison with controls at the first, but not the second scanning session. Thus, while the study failed to indicate increased luteal phase amygdala reactivity in women with PMDD, our findings suggest that anxiety proneness and progesterone levels modulate menstrual cycle related amygdala reactivity in women with PMDD.
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| 9. |
- Gingnell, Malin, et al.
(författare)
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Oral contraceptive use changes brain activity and mood in women with previous negative affect on the pill : A double-blinded, placebo-controlled randomized trial of a levonorgestrel-containing combined oral contraceptive
- 2013
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Ingår i: Psychoneuroendocrinology. - : Elsevier BV. - 0306-4530 .- 1873-3360. ; 38:7, s. 1133-1144
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE:Most women on combined oral contraceptives (COC) report high levels of satisfaction, but 4-10% complain of adverse mood effects. The aim of this randomized, double-blinded, placebo-controlled trial was to investigate if COC use would induce more pronounced mood symptoms than placebo in women with previous history of COC-induced adverse mood. A second aim was to determine if COC use is associated with changes in brain reactivity in regions previously associated with emotion processing.METHODS:Thirty-four women with previous experience of mood deterioration during COC use were randomized to one treatment cycle with a levonorgestrel-containing COC or placebo. An emotional face matching task (vs. geometrical shapes) was administered during functional magnetic resonance imaging (fMRI) prior to and during the COC treatment cycle. Throughout the trial, women recorded daily symptom ratings on the Cyclicity Diagnoser (CD) scale.RESULTS:During the last week of the treatment cycle COC users had higher scores of depressed mood, mood swings, and fatigue than placebo users. COC users also had lower emotion-induced reactivity in the left insula, left middle frontal gyrus, and bilateral inferior frontal gyri as compared to placebo users. In comparison with their pretreatment cycle, the COC group had decreased emotion-induced reactivity in the bilateral inferior frontal gyri, whereas placebo users had decreased reactivity in the right amygdala.CONCLUSION:COC use in women who previously had experienced emotional side effects resulted in mood deterioration, and COC use was also accompanied by changes in emotional brain reactivity. These findings are of relevance for the understanding of how combined oral contraceptives may influence mood. Placebo-controlled fMRI studies in COC sensitive women could be of relevance for future testing of adverse mood effects in new oral contraceptives.
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| 10. |
- Gingnell, Malin, 1982-
(författare)
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Ovarian Steroid Hormones, Emotion Processing and Mood
- 2013
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- It is known that some psychiatric disorders may deteriorate in relation to the menstrual cycle. However, in some conditions, such as premenstrual dysphoric disorder (PMDD), symptomatology is triggered mainly by the variations in ovarian steroid hormones. Although symptoms induced by fluctuations in ovarian steroids often are affective, little is known about how emotion processing in women is influenced by variations, or actual levels, of ovarian steroid hormones.The general aim of this thesis was to evaluate menstrual cycle effects on reactivity in emotion generating and controlling areas in the corticolimbic system to emotional stimulation and anticipation, in healthy controls and women with PMDD. A second aim was to evaluate corticolimbic reactivity during long-term administration of exogenous ovarian steroids.In study I, III and IV effects of the menstrual cycle on emotional reactivity in women with PMDD was studied. In study I, women with PMDD in displayed higher amygdala reactivity than healthy controls to emotional faces, not in the luteal phase as was hypothesised, but in the follicular phase. No difference between menstrual cycle phases was obtained in women with PMDD, while healthy controls had an increased reactivity in the luteal phase. The results of study I was further elaborated in study III, where women with PMDD were observed to have an increased anticipatory reactivity to negative emotional stimuli. However, no differences in amygdala reactivity to emotional stimuli were obtained across the menstrual cycle. Finally, in study IV the hypothesis that amygdala reactivity increase in the luteal phase in women with PMDD is linked to social stimuli rather than generally arousing stimuli was suggested, tested and supported.In study II, re-exposure to COC induced mood symptoms de novo in women with a previous history of COC-induced adverse mood. Women treated with COC reported increased levels of mood symptoms both as compared to before treatment, and as compared to the placebo group. There was a relatively strong correlation between depressive scores before and during treatment. The effects of repeated COC administration on subjective measures and brain function were however dissociated with increased aversive experiences accompanied by reduced reactivity in the insular cortex.
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