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Ergebnisse 3 Einträge
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Phobic responses are strong emotional reactions towards phobic objects, which can be described as a deficit in the automatic regulation of emotions. Difficulties in the voluntary cognitive control of these emotions suggest a further phobia-specific deficit in effortful emotion regulation mechanisms. The actual study is based on this emotion regulation conceptualization of specific phobias. The aim is to investigate the neural correlates of these two emotion regulation deficits in spider phobics. Sixteen spider phobic females participated in a functional magnetic resonance imaging (fMRI) study in which they were asked to voluntarily up- and down-regulate their emotions elicited by spider and generally aversive pictures with a reappraisal strategy. In line with the hypothesis concerning an automatic emotion regulation deficit, increased activity in the insula and reduced activity in the ventromedial prefrontal cortex was observed. Furthermore, phobia-specific effortful regulation within phobics was associated with altered activity in medial prefrontal cortex areas. Altogether, these results suggest that spider phobic subjects are indeed characterized by a deficit in the automatic as well as the effortful regulation of emotions elicited by phobic compared with aversive stimuli. These two forms of phobic emotion regulation deficits are associated with altered activity in different medial prefrontal cortex subregions.
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Findings from several functional magnetic resonance imaging (fMRI) studies implicate the existence of a distinct neural disgust substrate, whereas others support the idea of distributed and integrative brain systems involved in emotional processing. In the present fMRI experiment 12 healthy females viewed pictures from four emotion categories. Two categories were disgust-relevant and depicted contamination or mutilation. The other scenes showed attacks (fear) or were affectively neutral. The two types of disgust elicitors received comparable ratings for disgust, fear and arousal. Both were associated with activation of the occipitotemporal cortex, the amygdala, and the orbitofrontal cortex; insula activity was nonsignificant in the two disgust conditions. Mutilation scenes induced greater inferior parietal activity than contamination scenes, which might mirror their greater capacity to capture attention. Our results are in disagreement with the idea of selective disgust processing at the insula. They point to a network of brain regions involved in the decoding of stimulus salience and the regulation of attention.
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RATIONALE: Biased processing of drug-associated stimuli is believed to be a crucial feature of addiction. Particularly, an attentional bias seems to contribute to the disorder's maintenance. Recent studies suggest differential effects for stimuli associated with the beginning (BEGIN-smoking-stimuli) or the terminal stage of the smoking ritual (END-smoking-stimuli), with the former but not the later evoking high cue-reactivity. OBJECTIVE: The current study investigated the neuronal network underlying an attentional bias to BEGIN-smoking-stimuli and END-smoking-stimuli in smokers and tested the hypothesis that the attentional bias is greater for BEGIN-smoking-stimuli. METHODS: Sixteen non-deprived smokers and 16 non-smoking controls participated in an fMRI study. Drug pictures (BEGIN-smoking-stimuli, END-smoking-stimuli) and control pictures were overlaid with geometrical figures and presented for 300 ms. Subjects had to identify picture content (identification-task) or figure orientation (distraction-task). The distraction-task was intended to demonstrate attentional bias. RESULTS: Behavioral data revealed an attentional bias to BEGIN-smoking-stimuli but not to END-smoking-stimuli in both groups. However, only smokers showed mesocorticolimbic deactivations in the distraction-task with BEGIN-smoking-stimuli. Importantly, these deactivations were significantly stronger for BEGIN- than for END-smoking-stimuli and correlated with the attentional bias score. CONCLUSIONS: Several explanations may account for missing group differences in behavioral data. Brain data suggest smokers using regulatory strategies in response to BEGIN-smoking-stimuli to prevent the elicitation of motivational responses interfering with distraction-task performance. These strategies could be reflected in the observed deactivations and might lead to a performance level in smokers that is similar to that of non-smokers.
Erkunden
Team
- Vaitl (3)
Eintragsart
Sprache
- Englisch (3)
Thema
- Photic Stimulation/methods
- Adult (2)
- Animals (1)
- Attention/*physiology (1)
- Behavior, Addictive/*physiopathology (1)
- *Brain Mapping (2)
- Brain Mapping/methods/*psychology (1)
- Carbamide Peroxide (1)
- Cerebral Cortex/*blood supply/physiology (1)
- Cerebral Cortex/*physiopathology (1)
- Cues (1)
- Drug Combinations (1)
- Emotions/*physiology (2)
- Expressed Emotion/*physiology (1)
- *Facial Expression (1)
- Female (2)
- Humans (3)
- Image Processing, Computer-Assisted/methods (1)
- Limbic System/*physiopathology (1)
- *Magnetic Resonance Imaging (1)
- Magnetic Resonance Imaging/methods (1)
- Magnetic Resonance Imaging/methods/psychology (1)
- Male (1)
- Neural Inhibition/*physiology (1)
- Neural Pathways/physiopathology (1)
- Neuronal Plasticity/physiology (1)
- Oxygen/blood (1)
- Pattern Recognition, Visual/physiology (1)
- Pattern Recognition, Visual/*physiology (1)
- Peroxides/blood (1)
- Phobic Disorders/*psychology (1)
- Prefrontal Cortex/blood supply/physiopathology (1)
- Psychophysics (1)
- Reflex, Startle/physiology (1)
- Self Concept (1)
- Smoking/*physiopathology/psychology (1)
- *Spiders (1)
- Urea/analogs & derivatives/blood (1)
- Visual Perception/physiology (1)