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2.
Biol Psychiatry ; 50(4): 292-8, 2001 Aug 15.
Article de Anglais | MEDLINE | ID: mdl-11522264

RÉSUMÉ

BACKGROUND: Intense and rapidly changing mood states are a major feature of borderline personality disorder (BPD); however, there have only been a few studies investigating affective processing in BPD, and in particular no neurofunctional correlates of abnormal emotional processing have been identified so far. METHODS: Six female BPD patients without additional major psychiatric disorder and six age-matched female control subjects underwent functional magnetic resonance imaging (fMRI) to measure regional cerebral hemodynamic changes following brain activity when viewing 12 standardized emotionally aversive slides compared to 12 neutral slides, which were presented in random order. RESULTS: Our main finding was that BPD subjects but not control subjects were characterized by an elevated blood oxygenation level dependent fMRI signal in the amygdala on both sides. In addition, activation of the medial and inferolateral prefrontal cortex was seen in BPD patients. Both groups showed activation in the temporo-occipital cortex including the fusiform gyrus in BPD subjects but not in control subjects. CONCLUSIONS: Enhanced amygdala activation in BPD is suggested to reflect the intense and slowly subsiding emotions commonly observed in response to even low-level stressors. Borderline subjects' perceptual cortex may be modulated through the amygdala leading to increased attention to emotionally relevant environmental stimuli.


Sujet(s)
Amygdale (système limbique)/anatomie et histologie , Amygdale (système limbique)/physiopathologie , Trouble de la personnalité limite/physiopathologie , Imagerie par résonance magnétique , Affect/physiologie , Éveil/physiologie , Trouble de la personnalité limite/diagnostic , Femelle , Humains , Lobe occipital/anatomie et histologie , Lobe occipital/physiologie , Cortex préfrontal/anatomie et histologie , Cortex préfrontal/physiologie , Lobe temporal/anatomie et histologie , Lobe temporal/physiologie , Perception visuelle/physiologie
3.
AJNR Am J Neuroradiol ; 20(10): 1907-14, 1999.
Article de Anglais | MEDLINE | ID: mdl-10588117

RÉSUMÉ

BACKGROUND AND PURPOSE: One major limitation of current functional MR (fMR) imaging is its inability to clarify the relationship between sites of cortical neuronal activation, small parenchymal venules that are in close proximity to these sites, and large draining veins distant from the active parenchyma. We propose to use gradient-echo blood oxygenation level-dependent (BOLD) fMR time courses to differentiate large draining veins from parenchymal microvasculature. METHODS: In eight research subjects, five of whom presented with space-occupying lesions near the central sulcus, gradient-echo fMR imaging was performed during alternating periods of rest and motor activation. MR signal time courses from parenchymal regions and draining veins of different diameters, which were identified using contrast-enhanced T1-weighted scans, were evaluated. Percent signal changes (deltaS) and the time to the onset of MR signal rise (T0) were calculated. RESULTS: Mean delta(S) for all subjects was 2.3% (SD+/-0.7%) for parenchymal activation, 4.3% (SD +1.0%) for sulcal macrovasculature, and 7.3 (SD+/-1.1%) for large superficial bridging veins. The mean time to onset of MR signal increase was 4.4 seconds for parenchymal task-related hemodynamic changes and 6.6 seconds for venous hemodynamic changes, regardless of vessel size. Both the differences in delta(S) and T0 were statistically significant between venous and parenchymal activation (P < .0001). CONCLUSION: Gradient-echo fMR imaging reveals hemodynamic task-related changes regardless of vessel size and therefore might show macrovascular changes distal to the site of neuronal activity. MR-signal time-course characteristics (delta(S) and T0) can be used to differentiate between small parenchymal and larger pial draining vessels, which is especially important in presurgical planning of neurosurgical procedures involving functionally important brain regions. The knowledge about the differences in (delta)S and T0 between micro- and macrovasculature might lead to a more accurate description of the spatial distribution of underlying neuronal activity.


Sujet(s)
Encéphale/vascularisation , Amélioration d'image , Imagerie par résonance magnétique , Oxygène/sang , Adulte , Sujet âgé , Volume sanguin/physiologie , Tumeurs du cerveau/vascularisation , Tumeurs du cerveau/diagnostic , Artères cérébrales/anatomopathologie , Veines de l'encéphale/anatomopathologie , Femelle , Hémodynamique/physiologie , Humains , Mâle , Microcirculation/anatomopathologie , Adulte d'âge moyen , Consommation d'oxygène/physiologie , Débit sanguin régional/physiologie , Transmission synaptique/physiologie
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