Steering matter wave superradiance with an ultranarrow-band optical cavity

A superfluid atomic gas is prepared inside an optical resonator with an ultranarrow bandwidth on the order of the single photon recoil energy. When a monochromatic off-resonant laser beam irradiates the atoms, above a critical intensity the cavity emits superradiant light pulses with a duration on the order of its photon storage time. The atoms are collectively scattered into coherent superpositions of discrete momentum states, which can be precisely controlled by adjusting the cavity resonance frequency. With appropriate pulse sequences the entire atomic sample can be collectively accelerated or decelerated by multiples of two recoil momenta. The instability boundary for the onset of matter wave superradiance is recorded and its main features are explained by a mean field model.

The rationale behind complete mesocolic excision (CME) and a central vascular ligation for colon cancer in open and laparoscopic surgery : proceedings of a consensus conference

BACKGROUND

It has been evident for a while that the result after resection for colon cancer may not have been optimal. Several years ago, this was showed by some leading surgeons in the USA but a concept of improving results was not consistently pursued. Later, surgeons in Europe and Japan have increasingly adopted the more radical principle of complete mesocolic excision (CME) as the optimal approach for colon cancer. The concept of CME is a similar philosophy to that of total mesorectal excision for rectal cancer and precise terminology and optimal surgery are key factors.

METHOD

There are three essential components to CME. The main component involves a dissection between the mesenteric plane and the parietal fascia and removal of the mesentery within a complete envelope of mesenteric fascia and visceral peritoneum that contains all lymph nodes draining the tumour area (Hohenberger et al., Colorectal Disease 11:354-365, 2009; West et al., J Clin Oncol 28:272-278, 2009). The second component is a central vascular tie to completely remove all lymph nodes in the central (vertical) direction. The third component is resection of an adequate length of bowel to remove involved pericolic lymph nodes in the longitudinal direction.

RESULT

The oncological rationale for CME and various technical aspects of the surgical management will be explored.

CONCLUSION

The consensus conference agreed that there are sound oncological hypotheses for a more radical approach than has been common up to now. However, this may not necessarily apply in early stages of the tumour stage. Laparoscopic resection appears to be equally well suited for resection as open surgery.

Operationalized psychodynamic diagnosis as an instrument to transfer psychodynamic constructs into neuroscience

This theoretical article makes a contribution to the field of "psychoanalytically informed neuroscience". First, central characteristics of psychoanalysis and neuroscience are briefly described leading into three epistemic dichotomies. Neuroscience versus psychoanalysis display almost opposing methodological approaches (reduction vs. expansion), test quality emphases (reliability vs. validity) and meaning of results (correlation vs. explanation). The critical point is to reach an intermediate level: in neuroscience an adequate position integrating both aspects-objective and subjective-of dual-aspect monism, and in psychoanalysis the appropriate level for the scientific investigation of its central concepts. As a suggestion to reach that level in both fields the system of Operationalized Psychodynamic Diagnosis (OPD; OPD Task Force, 2008) is presented. Combining aspects of both fields areas, expansion and reduction as well as reliability and validity, OPD could be a fruitful tool to transfer psychodynamic constructs into neuroscience. The article closes with a short description of recent applications of OPD in neuroscience.

Neural activity in relation to empirically derived personality syndromes in depression using a psychodynamic fMRI paradigm

OBJECTIVE

The heterogeneity between patients with depression cannot be captured adequately with existing descriptive systems of diagnosis and neurobiological models of depression. Furthermore, considering the highly individual nature of depression, the application of general stimuli in past research efforts may not capture the essence of the disorder. This study aims to identify subtypes of depression by using empirically derived personality syndromes, and to explore neural correlates of the derived personality syndromes.

MATERIALS AND METHODS

In the present exploratory study, an individually tailored and psychodynamically based functional magnetic resonance imaging paradigm using dysfunctional relationship patterns was presented to 20 chronically depressed patients. RESULTS from the Shedler-Westen Assessment Procedure (SWAP-200) were analyzed by Q-factor analysis to identify clinically relevant subgroups of depression and related brain activation.

RESULTS

The principle component analysis of SWAP-200 items from all 20 patients lead to a two-factor solution: "Depressive Personality" and "Emotional-Hostile-Externalizing Personality." Both factors were used in a whole-brain correlational analysis but only the second factor yielded significant positive correlations in four regions: a large cluster in the right orbitofrontal cortex (OFC), the left ventral striatum, a small cluster in the left temporal pole, and another small cluster in the right middle frontal gyrus.

DISCUSSION

The degree to which patients with depression score high on the factor "Emotional-Hostile-Externalizing Personality" correlated with relatively higher activity in three key areas involved in emotion processing, evaluation of reward/punishment, negative cognitions, depressive pathology, and social knowledge (OFC, ventral striatum, temporal pole). RESULTS may contribute to an alternative description of neural correlates of depression showing differential brain activation dependent on the extent of specific personality syndromes in depression.

Neural activity during free association to conflict-related sentences

Psychodynamic conflicts form an important construct to understand the genesis and maintenance of mental disorders. Conflict-related themes should therefore provoke strong reactions on the behavioral, physiological, and neural level. We confronted N = 18 healthy subjects with a vast array of sentences describing typical psychodynamic conflict themes in the fMRI scanner and let them associate spontaneously in reaction. The overt associations were then analyzed according to psychoanalytic theory and the system of operationalized psychodynamic diagnosis and used as a genuinely psychodynamic indicator, whether each potentially conflict-related sentence actually touched a conflict theme of the individual. Behavioral, physiological, and neural reactions were compared between those subjects with an “apparent conflict” and those with “absent conflicts.” The first group reported stronger agreement with the conflict-related sentences, more negative valence in reaction, had higher levels of skin conductance reactivity and exhibited stronger activation in the anterior cingulate cortex, amongst other functions involved in emotion processing and conflict-monitoring. In conjunction, we interpret this activity as a possible correlate of subjects’ inherent reactions and regulatory processes evoked by conflict themes. This study makes a point for the fruitfulness of the neuropsychoanalytic endeavor by using free association, the classical technique most commonly used in psychoanalysis, to investigate aspects of conflict processing in neuroimaging.

Providers' lack of knowledge about herpes zoster in HIV-infected patients is among barriers to herpes zoster vaccination

Identification of perceptions about herpes zoster (HZ) disease, vaccine effectiveness and safety, and vaccine recommendations may impact immunization practices of physicians for HIV-infected patients. A survey was used to quantify knowledge of HZ as well as determine physician immunization perceptions and practices. There were 272/1700 respondents (16%). Correct answers for the incidence of varicella zoster virus (VZV) infection in adults and incidence of HZ in HIV-infected patients were recorded by 14% and 10% of providers, respectively. Providers reported poor knowledge of the incidence of disease recurrence in HIV-infected patients (41% correct), potency of HZ vaccine (47.5% correct) and mechanism of protection against reactivation of VZV (66% correct). Most (88%) agreed that HZ was a serious disease, and 73% believed that the burden of disease made vaccination important. A majority (75%) did not vaccinate HIV patients with HZ vaccine regardless of antiretroviral therapy status. Barriers to administration included safety concerns, concern that vaccine would not prevent HZ, risk of HZ dissemination, reimbursement issues and lack of Infectious Diseases Society of America (IDSA) guidelines. Only 38% of providers agreed that CDC guidelines were clear and 50% believed that clinical trials were needed prior to use of HZ vaccine in HIV-infected patients. Education about HZ is needed among HIV providers. Providers perceived vaccination as important, but data on vaccine safety and clear guidance from the CDC on this issue are lacking.

Can the neural basis of repression be studied in the MRI scanner? New insights from two free association paradigms

BACKGROUND

The psychodynamic theory of repression suggests that experiences which are related to internal conflicts become unconscious. Previous attempts to investigate repression experimentally were based on voluntary, intentional suppression of stimulus material. Unconscious repression of conflict-related material is arguably due to different processes, but has never been studied with neuroimaging methods.

METHODS

We used functional magnetic resonance imaging (fMRI) in addition with skin conductance recordings during two free association paradigms to identify the neural mechanisms underlying forgetting of freely associated words according to repression theory.

RESULTS

In the first experiment, free association to subsequently forgotten words was accompanied by increases in skin conductance responses (SCRs) and reaction times (RTs), indicating autonomic arousal, and by activation of the anterior cingulate cortex. These findings are consistent with the hypothesis that these associations were repressed because they elicited internal conflicts. To test this idea more directly, we conducted a second experiment in which participants freely associated to conflict-related sentences. Indeed, these associations were more likely to be forgotten than associations to not conflict-related sentences and were accompanied by increases in SCRs and RTs. Furthermore, we observed enhanced activation of the anterior cingulate cortex and deactivation of hippocampus and parahippocampal cortex during association to conflict-related sentences.

CONCLUSIONS

These two experiments demonstrate that high autonomic arousal during free association predicts subsequent memory failure, accompanied by increased activation of conflict-related and deactivation of memory-related brain regions. These results are consistent with the hypothesis that during repression, explicit memory systems are down-regulated by the anterior cingulate cortex.

Nicotine differentially modulates antisaccade performance in healthy male non-smoking volunteers stratified for low and high accuracy

RATIONALE

Nicotinergic agents are currently examined as possible pro-cognitive drugs for a variety of clinical conditions marked by cognitive deficits, such as attention deficit hyperactivity disorder (ADHD) or schizophrenia. The response to acute nicotine is heterogeneous across subjects and samples; however, only a few reliable predictors of response have been identified.

OBJECTIVES

We tested the hypothesis that baseline performance level in cognitive control may be a predictor of the cognitive effects of nicotine.

METHODS

We tested 28 healthy Caucasian, male, non-smoking volunteers with the antisaccade task, an oculomotor measure of cognitive control. Participants were given a 7-mg nicotine patch in a double-blind, placebo-controlled, counterbalanced, within-subjects design. Subjects were stratified into high and low performers based on their antisaccade error rate in the placebo condition (median split).

RESULTS

Nicotine tended to reduce response time variability of prosaccade latency (p = 0.06). There was no main effect of nicotine on antisaccade error rate (p = 0.31). However, nicotine significantly reduced antisaccade error rate in the low-accuracy probands while leaving performance of the high-accuracy probands unaffected (interaction, p < 0.05). Furthermore, we found a nicotine-induced reduction of response time variability of antisaccade latency at one target location in the low-performing group (interaction, p < 0.05).

CONCLUSIONS

The present results demonstrate the importance of baseline performance differences for the effectiveness of pharmacological enhancement of cognitive control. More generally, the results suggest that stimulation of the nicotinic acetylcholine receptor system might be an effective way of improving cognition in people with poor cognitive performance, such as patients with ADHD or schizophrenia.

Changes in prefrontal-limbic function in major depression after 15 months of long-term psychotherapy

Neuroimaging studies of depression have demonstrated treatment-specific changes involving the limbic system and regulatory regions in the prefrontal cortex. While these studies have examined the effect of short-term, interpersonal or cognitive-behavioural psychotherapy, the effect of long-term, psychodynamic intervention has never been assessed. Here, we investigated recurrently depressed (DSM-IV) unmedicated outpatients (N = 16) and control participants matched for sex, age, and education (N = 17) before and after 15 months of psychodynamic psychotherapy. Participants were scanned at two time points, during which presentations of attachment-related scenes with neutral descriptions alternated with descriptions containing personal core sentences previously extracted from an attachment interview. Outcome measure was the interaction of the signal difference between personal and neutral presentations with group and time, and its association with symptom improvement during therapy. Signal associated with processing personalized attachment material varied in patients from baseline to endpoint, but not in healthy controls. Patients showed a higher activation in the left anterior hippocampus/amygdala, subgenual cingulate, and medial prefrontal cortex before treatment and a reduction in these areas after 15 months. This reduction was associated with improvement in depressiveness specifically, and in the medial prefrontal cortex with symptom improvement more generally. This is the first study documenting neurobiological changes in circuits implicated in emotional reactivity and control after long-term psychodynamic psychotherapy.

Regulation of emotions in the community: suppression and reappraisal strategies and its psychometric properties

Objective: The German Version of the Emotion Regulation Questionnaire (ERQ) has recently been published. The questionnaire investigates two common emotion regulation strategies (10 items) on two scales (suppression, reappraisal). Major aims of the study were to assess the reliability and factor structure of the ERQ, to determine population based norms and to investigate relations of suppression and reappraisal to anxiety, depression and demographic characteristics.

Methods: In a representative community study (N=2524) we assessed emotion regulation strategies, anxiety, depression (Hospital Anxiety and Depression Scale), and demographic variables. The mean age of the participants was 49.4 (SD 18.2) years. 55.5% were female. The age-groups were represented in comparable proportions. The representativeness of the sample was ensured by drawings of ADM (Arbeitskreis Deutscher Marktforscher) samples und by comparison with the data of German Federal Statistical Office.

Results: Confirmatory factor analysis could not fully confirm the original factor structure, we kept the original scaling, except a modification regarding item 8. Internal consistencies were acceptable for the original and the modified version: reappraisal (Cronbach’s alpha = 0.82) and suppression (alpha = 0.76). Norms are presented as percentile scores for age groups and gender. Reappraisal correlated negative with anxiety and depression, whereas we could find a positive relationship of suppression with anxiety and depression. In a linear regression model suppression was predicted by depression, a lower level of education, male gender, and lower income.

Conclusions: The ERQ is a short instrument to assess emotion regulation strategies economically, e.g. in larger community based studies. We could demonstrate sufficient psychometric properties of the German version of the ERQ: reliability, factor structure and indicators for construct validity. Because of the cross sectional character of our study it remains unclear whether reappraisal is protective and suppression is unfavourable regarding mental health or whether life circumstances and psychic symptoms lead to a suppression of emotions.

Why we still don't understand the depressed brain - Not going beyond snapshots

Although remarkable progress has been made in the search for the brain correlates of depression with neuroimaging methods, we still find a heterogeneity of results and lack of consensus. This short commentary proposes a theoretical reason for this situation linking it to the methods of conducting neuroimaging studies of depression and the ways to interpret findings. If we only take one snapshot of the “depressed brain”, the brain activity is presumably the result of four interacting components: neural predispositions, depressogenic pathology, changes caused by (chronic) depression, and compensatory brain mechanisms. The four components will be discussed briefly along with arguments why confusion of them might confuse our view of the brain in depression. After a short presentation of promising new longitudinal studies, this commentary gives first hints how we could go beyond snapshots to better understand the brain in depression.

The influence of neuroticism and psychological symptoms on the assessment of images in three-dimensional emotion space

Objective: The present study investigated the influence of neuroticism (NEO Five-Factor Inventory (NEO-FFI)) and psychological symptoms (Brief Symptom Inventory (BSI)) on pleasure, arousal, and dominance (PAD) ratings of the International Affective Picture System (IAPS).

Methods: The subjects (N=131) were presented with images from the IAPS (30 images) and new images (30 images). The influence of neuroticism and BSI (median split: high vs. low) on the assessment of pleasure, arousal and dominance of the images was examined. Correlations of pleasure, arousal and dominance were presented in a 3-D video animation.

Results: Subjects with high scores (compared to subjects with low scores by median split) of neuroticism and psychological symptoms of the BSI rated the presented emotional images more negative in the valence dimension (pleasure), higher in arousal and less dominant.

Conclusion: Neuroticism and psychological symptoms influence the subjective emotional evaluation of emotional images. Therefore the location in the three-dimensional emotion space depends on individual differences. Such differences must be kept in mind, if correlations between emotion ratings and other variables like psychobiological measures are analyzed.

Neural correlates of the perception of dynamic versus static facial expressions of emotion

Aim: This study investigated brain areas involved in the perception of dynamic facial expressions of emotion.

Methods: A group of 30 healthy subjects was measured with fMRI when passively viewing prototypical facial expressions of fear, disgust, sadness and happiness. Using morphing techniques, all faces were displayed as still images and also dynamically as a film clip with the expressions evolving from neutral to emotional.

Results: Irrespective of a specific emotion, dynamic stimuli selectively activated bilateral superior temporal sulcus, visual area V5, fusiform gyrus, thalamus and other frontal and parietal areas. Interaction effects of emotion and mode of presentation (static/dynamic) were only found for the expression of happiness, where static faces evoked greater activity in the medial prefrontal cortex.

Conclusions: Our results confirm previous findings on neural correlates of the perception of dynamic facial expressions and are in line with studies showing the importance of the superior temporal sulcus and V5 in the perception of biological motion. Differential activation in the fusiform gyrus for dynamic stimuli stands in contrast to classical models of face perception but is coherent with new findings arguing for a more general role of the fusiform gyrus in the processing of socially relevant stimuli.