Evidence for smaller right amygdala volumes in posttraumatic stress disorder following childhood trauma.

Hippocampus and amygdala volumes in posttraumatic stress disorder (PTSD) related to childhood trauma are relatively understudied, albeit the potential importance to the disorder. Whereas some studies reported smaller hippocampal volumes, little evidence was found for abnormal amygdala volumes. Here we investigated hippocampus and amygdala volumes and shapes in an adult sample of PTSD patients related to childhood trauma.

Amygdala and Dorsal Anterior Cingulate Connectivity during an Emotional Working Memory Task in Borderline Personality Disorder Patients with Interpersonal Trauma History.

Working memory is critically involved in ignoring emotional distraction while maintaining goal-directed behavior. Antagonistic interactions between brain regions implicated in emotion processing, e.g.

Susceptibility to distraction by social cues in borderline personality disorder.

Background/aims: Individuals with borderline personality disorder (BPD) are highly sensitive to social rejection and show alterations in social perception. Increased susceptibility to social cues in patients with BPD might interfere with executive functions that play an important role in goal-directed behavior. The aim of this study was to investigate the influence of task-irrelevant (neutral vs.

Differential and distributed effects of dopamine neuromodulations on resting-state network connectivity.

Dopaminergic medications, used to treat neurochemical pathology and resultant symptoms in neuropsychiatric disorders, are of mixed efficacy and regularly associated with behavioural side effects. The possibility that dopamine exerts both linear and nonlinear ('inverted U-shaped') effects on cognitive neurocircuitry may explain this outcome variability. However, it has proven to be difficult to characterise neural manifestations of psychopharmacological effects in humans.

Dopamine-dependent architecture of cortico-subcortical network connectivity.

Maladaptive dopaminergic mediation of reward processing in humans is thought to underlie multiple neuropsychiatric disorders, including addiction, Parkinson's disease, and schizophrenia. Mechanisms responsible for the development of such disorders may depend on individual differences in neural signaling within large-scale cortico-subcortical circuitry. Using a combination of functional neuroimaging and pharmacological challenges in healthy volunteers, we identified opposing dopamine agonistic and antagonistic neuromodulatory effects on distributed functional interactions between specific subcortical regions and corresponding neocortical "resting-state" networks, known to be involved in distinct aspects of cognition and reward processing.

Dopamine modulates reward system activity during subconscious processing of sexual stimuli.

Dopaminergic medication influences conscious processing of rewarding stimuli, and is associated with impulsive-compulsive behaviors, such as hypersexuality. Previous studies have shown that subconscious subliminal presentation of sexual stimuli activates brain areas known to be part of the 'reward system'. In this study, it was hypothesized that dopamine modulates activation in key areas of the reward system, such as the nucleus accumbens, during subconscious processing of sexual stimuli.

Endogenous cortisol is associated with functional connectivity between the amygdala and medial prefrontal cortex.

Whether glucocorticoids mediate medial prefrontal cortex (mPFC) regulation of the amygdala in humans remains unclear. In the current study we investigated whether cortisol levels under relatively stress-free circumstances are related to amygdala resting-state functional connectivity with the mPFC. Resting-state fMRI data were acquired from 20 healthy male participants.

Beyond acute social stress: increased functional connectivity between amygdala and cortical midline structures.

Whereas we know a fair amount on the role of the amygdala in the acute stress response, virtually nothing is known about its role during the recovery period after the stress has waned. Functional connectivity analysis of the amygdala during this period might be useful in revealing brain circuits promoting adaptive recovery from a stressful event, as well as consolidation of emotionally relevant information in preparing for future challenges. Healthy participants were randomly assigned to either a psychosocial stress task (n=18; stress group) or a comparable non-stressful control procedure (n=20; controls).

Stress shifts brain activation towards ventral 'affective' areas during emotional distraction.

Acute stress has been shown to impair working memory (WM), and to decrease prefrontal activation during WM in healthy humans. Stress also enhances amygdala responses towards emotional stimuli. Stress might thus be specifically detrimental to WM when one is distracted by emotional stimuli.

Non-parametric model selection for subject-specific topological organization of resting-state functional connectivity.

In recent years, graph theory has been successfully applied to study functional and anatomical connectivity networks in the human brain. Most of these networks have shown small-world topological characteristics: high efficiency in long distance communication between nodes, combined with highly interconnected local clusters of nodes. Moreover, functional studies performed at high resolutions have presented convincing evidence that resting-state functional connectivity networks exhibits (exponentially truncated) scale-free behavior.

Propranolol reduces emotional distraction in working memory: a partial mediating role of propranolol-induced cortisol increases?

Noradrenalin modulates prefrontal function, such as working memory (WM), and is associated with enhanced distractibility, and enhanced memory for emotional events and stimuli. The beta-blocker propranolol has been shown to reduce memory for emotional stimuli. Herein we describe investigations aimed at assessing whether the administration of propranolol would reduce the interference by emotional distractions during WM performance.

Hydrocortisone reduces emotional distracter interference in working memory.

Several studies have shown that stress and glucocorticoids can impair prefrontal-dependent working memory (WM) performance. WM is the ability to attend to the task at hand, and to maintain relevant information in mind during a delay while ignoring irrelevant stimuli. Here, it is investigated whether stress hormones impair WM by reducing the ability to suppress distracting, irrelevant neutral and emotional stimuli.

Glucocorticoids Decrease Hippocampal and Prefrontal Activation during Declarative Memory Retrieval in Young Men.

Glucocorticoids (GCs, cortisol in human) are associated with impairments in declarative memory retrieval. Brain regions hypothesized to mediate these effects are the hippocampus and prefrontal cortex (PFC). Our aim was to use fMRI in localizing the effects of GCs during declarative memory retrieval.

Recall bias in reporting medically unexplained symptoms comes from semantic memory.

Objective: When people report somatic complaints retrospectively, they depend on their memory. Therefore, retrospective reports can be influenced by general beliefs on sickness and health from semantic memory. We hypothesized that individuals with medically unexplained symptoms (MUS) would have recall biases stronger than those of people without complaints when reporting symptoms retrospectively, and that this effect would be a function of time between symptom experience and report.