Posttraumatische Belastungsstörung
"Of special interest are four brain areas, the hyperactive amygdala,
the hippocampus with volume reduction as well as the cingulate gyrus and
orbitofrontal cortical regions, which may not be able to inhibit the hyperactive amygdala
to trauma related stimuli."
Q
"Functional activation studies of posttraumatic stress disorder (PTSD) using symptom provocation
paradigms have implicated dysfunction in limbic and paralimbic brain regions.
Increased or altered cerebral blood flow has been observed in amygdala and insula.
Decreased or absent activity has been seen in medial prefrontal and anterior cingulate cortex (ACC)."
Q
"Past trauma experience was associated with decreased amygdala activity
(i.e., less activity than healthy control subjects); however, combat control subjects deactivated this
region (i.e., greater activity to neutral scripts). All subjects deactivated medial frontal cortex;
PTSD patients had greater rostral anterior cingulate (rACC) deactivation compared with control groups,
who deactivated ventromedial prefrontal cortex (vmPFC)."
Q
"There is robust evidence of hypothalamic-pituitary-adrenal axis dysfunctions related to posttraumatic
stress disorder..."
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Betroffene Region |
Neurologische Veränderungen |
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Greater activity than matched comparison subjects in the insula
during negative emotional processing
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Insula activation correlated positively with PTSS severity during a response-inhibition task
in youth groups
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* "The OFC, which is thought to be involved in the extinction of fear conditioning and
the retrieval of emotional memory, might play an important role in the pathophysiology of PTSD."
Q
"A sub-group of youth with PTSS and a history of self-injurious behaviors
demonstrated increased insula and orbitofrontal activation when compared with those PTSS youth with
no self-injurious behaviors."
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"The mPFC plays a role in the "contextualization" of stimuli, and dysregulation
of contextualization processes might play a key role in the generation of PTSD symptoms."
Q
"In voxel-wise analyses, the authors found that adrenocorticotropic hormone responses
were covaried with regional cerebral blood flow (rCBF) in the dorsal medial prefrontal cortex,
rostral anterior cingulate cortex, and right insula, with some differences between PTSD patients
and comparison subjects."
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Hypoactivation in the ventromedial prefrontal cortex-structures linked to the experience
and regulation of emotion
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Altered neural responses in the ventral MPFC
during the processing of emotionally salient but trauma-unrelated stimuli
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"In the subgroup (of BPD patients) with additional PTSD, we observed right more than left activation
of anterior temporal lobes, mesiotemporal areas, amygdala, posterior cingulate gyrus,
occipital areas, and cerebellum (during the recall of traumatic memories)."
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"On average PTSD patients had a 6.9% smaller left hippocampal volume and a
6.6% smaller right hippocampal volume compared with control subjects."
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Hippocampal metabolism is suppressed to a greater extent by pharmacologic stimulation
of the noradrenergic system in persons with PTSD
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"Later on (n the stress response), when hormone levels have subsided but gene-mediated effects
of corticosteroids start to appear, the excitability is normalized to the pre-stress level,
in the CA1 hippocampal area, but possibly less so in the dentate gyrus and amygdala.
A disturbed balance between these early and late phases of the stress response as well
as a shift toward the relative contribution of the dentate/amygdala pathways may
explain why the normal restorative capacity fails in vulnerable people experiencing
a life-threatening situation, which could contribute to the development of PTSD."
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Greater activity than matched comparison subjects in the amygdala
during negative emotional processing
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Altered neural responses in the amygdala
during the processing of emotionally salient but trauma-unrelated stimuli
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Amygdala is hyperresponsive to fear-related stimuli
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Long-term alterations within the amygdala contribute to stress-related mnemonic symptoms
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Hypoactivation in the dorsal and rostral anterior cingulate cortices linked
to the experience and regulation of emotion
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Decreased or absent activity in the anterior cingulate cortex (ACC) during symptom provocation
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"Pituitary and adrenal hyperreactivity to exogenous corticotropin releasing factor and
adrenocorticotropic hormone is demonstrated in premenopausal women with chronic
posttraumatic stress disorder."
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"Urinary and plasma cortisol levels are considerably lower in PTSD patients than in
non-PTSD trauma survivors and normal controls. Furthermore, the circadian pattern of cortisol
release from the adrenal glands follows a greater dynamic range in PTSD than in patients
with major depression or in normal controls. The reduction in cortisol levels results from
an enhanced negative feedback by cortisol, which is secondary to an increased sensitivity of
glucocorticoid receptors in target tissues."
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"Results showed that sensory gating of the P1 potential was significantly decreased
at the 250 msec ISI, and that there was a numerical, but not a statistically significant,
decrease in sensory gating at the other intervals tested in both male and female PTSD
subjects compared to all control groups. Since the P1 potential may be generated,
at least in part, by the reticular activating system, dysregulation of sensory processing by elements
of this system may be present in PTSD."
Q
"When neurological or psychiatric disorders manifest symptoms related to arousal and
sleep-wake control, disturbances of elements of the reticular activating system must be considered
responsible."
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"The PTSD group failed to show differential activation during WM (working memory) updating,
and instead appeared to show abnormal recruitment of WM updating network regions during WM maintenance.
These regions included the bilateral dorsolateral prefrontal cortex (DLPFC) and the inferior parietal lobe (IPL).
Several other regions were significantly more activated in Controls than in PTSD during WM updating,
including the hippocampus, the anterior cingulate, and the brainstem pons, key regions that are consistently
implicated in the neurobiology of PTSD."
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"Although hypothalamic-pituitary-adrenal axis activation is generally considered to
be the hallmark of the stress response, many of the same stimuli that initiate this response
also activate the locus coeruleus-norepinephrine system. Given its functional attributes,
the parallel engagement of the locus coeruleus-norepinephrine system with the
hypothalamic-pituitary-adrenal axis serves to coordinate endocrine and cognitive limbs of the stress response."
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