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Abstract: Background: Inadequately treated postoperative pain can lead to longer healing processes, longer hospital stays, and the development of chronic pain. In a 900‐bed university hospital in Switzerland, pain scores were assessed systematically. The study's primary aim was to define whether the routine pain assessment on the ward is accurate and reproducible. Subsequently the obtained data were used for a benchmark analysis to determine the hospital's performance in pain assessment quality compared with similar centers. Methods: During a 3‐month period, PAIN OUT questionnaires were used for patients’ interviews. Patients were included randomly according to the daily surgical schedule. Pain scores were assessed routinely by nursing staff on the wards and compared to PAIN OUT data. The ascertained data were analyzed by descriptive statistics as well as the Wilcoxon test for nonparametric values using IBM SPSS. Results: 658 patients were included in the study. Comparing routine pain measurements with PAIN OUT results revealed that within the first 24 hours on the ward, pain scores were significantly lower than measured with PAIN OUT questionnaires. This difference increased with increasing pain scores. The quality of pain management of the hospital in which this study was performed ranged around the 50th percentile when compared to similar centers. Conclusion: The cross‐sectional data comparison of pain assessment by the ward staff and by interviews with the PAIN OUT questionnaire showed a large gap of underrated pain. The benchmark analysis with the method of PAIN OUT suggests a decent pain management among reference groups. [ABSTRACT FROM AUTHOR]

The graph theoretical analysis of structural magnetic resonance imaging (MRI) data has received a great deal of interest in recent years to characterize the organizational principles of brain networks and their alterations in psychiatric disorders, such as schizophrenia. However, the characterization of networks in clinical populations can be challenging, since the comparison of connectivity between groups is influenced by several factors, such as the overall number of connections and the structural abnormalities of the seed regions. To overcome these limitations, the current study employed the whole-brain analysis of connectional fingerprints in diffusion tensor imaging data obtained at 3 T of chronic schizophrenia patients (n = 16) and healthy, age-matched control participants (n = 17). Probabilistic tractography was performed to quantify the connectivity of 110 brain areas. The connectional fingerprint of a brain area represents the set of relative connection probabilities to all its target areas and is, hence, less affected by overall white and gray matter changes than absolute connectivity measures. After detecting brain regions with abnormal connectional fingerprints through similarity measures, we tested each of its relative connection probability between groups. We found altered connectional fingerprints in schizophrenia patients consistent with a dysconnectivity syndrome. While the medial frontal gyrus showed only reduced connectivity, the connectional fingerprints of the inferior frontal gyrus and the putamen mainly contained relatively increased connection probabilities to areas in the frontal, limbic, and subcortical areas. These findings are in line with previous studies that reported abnormalities in striatal-frontal circuits in the pathophysiology of schizophrenia, highlighting the potential utility of connectional fingerprints for the analysis of anatomical networks in the disorder. [ABSTRACT FROM AUTHOR]

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Background: Medication overuse headache (MOH) has been recognized as an important problem in headache patients although the pathophysiological mechanisms remain unclear. The diagnosis of MOH is based on clinical characteristics defined by the International Headache Society. The aim was the evaluation of the diagnostic criteria of MOH in a mixed population of chronic pain patients to gain information about the prevalence and possible associations with MOH. Methods: Data of all patients referred to the interdisciplinary pain clinic at the University Hospital of Zurich between September 2005 and December 2007 were retrospectively analyzed. Demographic data (age, sex, history of migration), as well as data about duration of pain disease, category of pain disease (neurological, psychiatric, rheumatologic, other), use of medication, history of trauma, and comorbidity of depression and anxiety have been collected. Results: Totally 178 of 187 consecutive chronic pain patients were included in the study. A total of 138 patients (78%) used analgesics on 15 or more days per month. Chronic headache was more prevalent among patients with analgesic overuse (39.8%) than without analgesic overuse (18%). The prevalence of MOH was 29%. The odds ratio (OR) for a patient with medication overuse to have chronic headache was 13.1 if he had a history of primary headache, compared to a patient without a primary headache syndrome. Furthermore, history of headache (OR 2.5, CI [1.13;5.44]), history of migration (OR 2.9, CI [1.31;6.32]) and comorbid depression (OR 3.5, CI [1.46;8.52]) were associated with overuse of acute medication, in general. Conclusions: Primary headaches have a high risk for chronification in patients overusing analgesics for other pain disorders. Whereas history of headache, history of migration and comorbidity of depression are independentely associated with analgesic overuse in this group of patients. [ABSTRACT FROM AUTHOR]

Little information is available on the pH sensitivity of the excitability properties of mammalian axons. Computer-assisted threshold tracking in humans has helped to define clinically relevant changes of nerve excitability in response to hyperventilation and ischaemia, but in vivo studies cannot directly differentiate between the impact of pH and other secondary factors. In this investigation, we applied an excitability testing protocol to a rat saphenous skin nerve in vitro preparation. Changes in extracellular pH were induced by altering pCO2 in the perfusate, and excitability properties of large myelinated fibres were measured in the pH range from 6.9 to 8.1. The main effect of protons on nerve excitability was a near linear increase in threshold which was accompanied by a decrease in strength-duration time constant reflecting mainly a decrease in persistent sodium current. In the recovery cycle, late subexcitability following 7 conditioning stimuli was substantially reduced at acid pH, indicating a block of slow but not of fast potassium channels. Changes in threshold electrotonus were complex, reflecting the combined effects of pH on multiple channel types. These results provide the first systematic data on pH sensitivity of mammalian nerve excitability properties, and may help in the interpretation of abnormal clinical excitability measurements. [ABSTRACT FROM AUTHOR]

We investigated the influence of spinal opioid receptor-sensitive muscle afferents on cortical changes following fatiguing unilateral knee-extensor exercise. On separate days, seven subjects performed an identical five sets of intermittent isometric right-quadriceps contractions, each consisting of eight submaximal contractions [63 ± 7% maximal voluntary contraction (MVC)] and one MVC. The exercise was performed following either lumbar interspinous saline injection or lumbar intrathecal fentanyl injection blocking the central projection of spinal opioid receptor-sensitive lower limb muscle afferents. To quantify exercise-induced peripheral fatigue, quadriceps twitch force ( Q) was assessed via supramaximal magnetic femoral nerve stimulation before and after exercise. Motor evoked potentials and cortical silent periods (CSPs) were evaluated via transcranial magnetic stimulation of the motor cortex during a 3% MVC pre-activation period immediately following exercise. End-exercise quadriceps fatigue was significant and similar in both conditions (Δ Q−35 and −39% for placebo and fentanyl, respectively; P= 0.38). Immediately following exercise on both days, motor evoked potentials were similar to those obtained prior to exercise. Compared with pre-exercise baseline, CSP in the placebo trial was 21 ± 5% longer postexercise ( P < 0.01). In contrast, CSP following the fentanyl trial was not significantly prolonged compared with the pre-exercise baseline (6 ± 4%). Our findings suggest that the central effects of spinal opioid receptor-sensitive muscle afferents might facilitate the fatigue-induced increase in CSP. Furthermore, since the CSP is thought to reflect inhibitory intracortical interneuron activity, which may contribute to central fatigue, our findings imply that spinal opioid receptor-sensitive muscle afferents might influence central fatigue by facilitating intracortical inhibition. [ABSTRACT FROM AUTHOR]

Laterality is a characteristic principle of the organization of the brain systems for language, and reduced hemispheric asymmetry has been considered a risk factor for schizophrenia. Here we sought support for the risk factor hypothesis by investigating whether reduced asymmetry of temporal lobe structure and function is also present in unaffected relatives. Sixteen schizophrenia patients, 16 age-matched first-degree relatives, and 15 healthy controls underwent high-resolution three-dimensional anatomical imaging and functional magnetic resonance imaging during auditory stimulation. Both the overall auditory cortex and planum temporale volumes and the lateralization to the left hemisphere were markedly reduced in patients. The decrease of lateralization correlated with increased severity of symptoms. In addition, both the overall functional activation in response to auditory stimulation and its asymmetry were reduced in the patients. Relatives had intermediate values between patients and controls on both structural and functional measures. This study provides added support for the idea that reduced hemispheric asymmetry is a biological risk factor for schizophrenia. [ABSTRACT FROM AUTHOR]

Background: Treatment of long-standing complex regional pain syndrome (CRPS) is empirical and often of limited efficacy. Preliminary data suggest that the immune system is involved in sustaining this condition and that treatment with low-dose intravenous immunoglobulin (IVIG) may substantially reduce pain in some patients.Objective: To evaluate the efficacy of IVIG in patients with longstanding CRPS under randomized, controlled conditions.Design: A randomized, double-blind, placebo-controlled crossover trial. (National Research Registry number: N0263177713; International Standard Randomised Controlled Trial Number Registry: 63918259)Setting: University College London Hospitals Pain Management Centre.Patients: Persons who had pain intensity greater than 4 on an 11-point (0 to 10) numerical rating scale and had CRPS for 6 to 30 months that was refractory to standard treatment.Intervention: IVIG, 0.5 g/kg, and normal saline in separate treatments, divided by a washout period of at least 28 days.Measurements: The primary outcome was pain intensity 6 to 19 days after the initial treatment and the crossover treatment.Results: 13 eligible participants were randomly assigned between November 2005 and May 2008; 12 completed the trial. The average pain intensity was 1.55 units lower after IVIG treatment than after saline (95% CI, 1.29 to 1.82; P < 0.001). In 3 patients, pain intensity after IVIG was less than after saline by 50% or more. No serious adverse reactions were reported.Limitation: The trial was small, and recruitment bias and chance variation could have influenced results and their interpretation.Conclusion: IVIG, 0.5 g/kg, can reduce pain in refractory CRPS. Studies are required to determine the best immunoglobulin dose, the duration of effect, and when repeated treatments are needed.Primary Funding Source: Association of Anaesthetists of Great Britain and Ireland, University College London Hospitals Charity, and CSL-Behring. [ABSTRACT FROM AUTHOR]

Background: Treatment of long-standing complex regional pain syndrome (CRPS) is empirical and often of limited efficacy. Preliminary data suggest that the immune system is involved in sustaining this condition and that treatment with low-dose intravenous immunoglobulin (IVIG) may substantially reduce pain in some patients. Objective: To evaluate the efficacy of IVIG in patients with longstanding CRPS under randomized, controlled conditions. Design: A randomized, double-blind, placebo-controlled crossover trial. (National Research Registry number: N0263177713; International Standard Randomised Controlled Trial Number Registry: 63918259) Setting: University College London Hospitals Pain Management Centre. Patients: Persons who had pain intensity greater than 4 on an 11-point (0 to 10) numerical rating scale and had CRPS for 6 to 30 months that was refractory to standard treatment. Intervention: IVIG, 0.5 g/kg, and normal saline in separate treatments, divided by a washout period of at least 28 days. Measurements: The primary outcome was pain intensity 6 to 19 days after the initial treatment and the crossover treatment. Results: 13 eligible participants were randomly assigned between November 2005 and May 2008; 12 completed the trial. The average pain intensity was 1.55 units lower after IVIG treatment than after saline (95% CI, 1.29 to 1.82; P = 0.001). In 3 patients, pain intensity after IVIG was less than after saline by 50% or more. No serious adverse reactions were reported. Limitation: The trial was small, and recruitment bias and chance variation could have influenced results and their interpretation. Conclusion: IVIG, 0.5 g/kg, can reduce pain in refractory CRPS. Studies are required to determine the best immunoglobulin dose, the duration of effect, and when repeated treatments are needed. Primary Funding Source: Association of Anaesthetists of Great Britain and Ireland, University College London Hospitals Charity, and CSL-Behring. [ABSTRACT FROM AUTHOR]

The idea of an organized mode of brain function that is present as default state and suspended during goal-directed behaviors has recently gained much interest in the study of human brain function. The default mode hypothesis is based on the repeated observation that certain brain areas show task-induced deactivations across a wide range of cognitive tasks. In this event-related functional resonance imaging study we tested the default mode hypothesis by comparing common and selective patterns of BOLD deactivation in response to the demands on visual attention and working memory (WM) that were independently modulated within one task. The results revealed task-induced deactivations within regions of the default mode network (DMN) with a segregation of areas that were additively deactivated by an increase in the demands on both attention and WM, and areas that were selectively deactivated by either high attentional demand or WM load. Attention-selective deactivations appeared in the left ventrolateral and medial prefrontal cortex and the left lateral temporal cortex. Conversely, WM-selective deactivations were found predominantly in the right hemisphere including the medial-parietal, the lateral temporo-parietal, and the medial prefrontal cortex. Moreover, during WM encoding deactivated regions showed task-specific functional connectivity. These findings demonstrate that task-induced deactivations within parts of the DMN depend on the specific characteristics of the attention and WM components of the task. The DMN can thus be subdivided into a set of brain regions that deactivate indiscriminately in response to cognitive demand ('the core DMN') and a part whose deactivation depends on the specific task. Hum Brain Mapp, 2010. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

The CNS-restricted versican splice-variant V2 is a large chondroitin sulfate proteoglycan incorporated in the extracellular matrix surrounding myelinated fibers and particularly accumulating at nodes of Ranvier. In vitro, it is a potent inhibitor of axonal growth and therefore considered to participate in the reduction of structural plasticity connected to myelination. To study the role of versican V2 during postnatal development, we designed a novel isoform-specific gene inactivation approach circumventing early embryonic lethality of the complete knock-out and preventing compensation by the remaining versican splice variants. These mice are viable and fertile; however, they display major molecular alterations at the nodes of Ranvier. While the clustering of nodal sodium channels and paranodal structures appear in versican V2-deficient mice unaffected, the formation of the extracellular matrix surrounding the nodes is largely impaired. The conjoint loss of tenascin-R and phosphacan from the perinodal matrix provide strong evidence that versican V2, possibly controlled by a nodal receptor, organizes the extracellular matrix assembly in vivo. [ABSTRACT FROM AUTHOR]

Background: Deficits in visual processing are a prominent feature of Alzheimer’s disease (AD), yet the cognitive and neuropathological mechanisms underlying these deficits are poorly understood. In the current study, we examined the hypothesis that perceptual organization is specifically impaired in AD compared to other dementias. Methods: We examined perceptual organization with a psychophysically well-controlled measure of contour integration in patients with AD (n = 17), vascular dementia (n = 5), frontotemporal dementia (n = 5) and mild cognitive impairment (n = 10) and 11 age-matched healthy controls. Results: Patients with AD differed significantly in their ability to detect contours comprised of Gabor elements as detection relied increasingly on long-range spatial interactions. Impairments in contour integration were particularly pronounced in AD patients with atrophy and gliosis of white matter in the occipital lobe. Deficits in perceptual organization were not found in patients with other dementias and participants with mild cognitive impairment. Conclusions: These results suggest that a subgroup of AD patients is characterized by a specific deficit in visual perceptual organization, which might reflect the impaired functional integrity of occipital cortico-cortical pathways. Copyright © 2008 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Neuroinflammation is observed in neurodegenerative diseases like Alzheimer’s disease (AD). However, a little is known about the mechanisms of neural-immune interactions. The involvement of peripheral T-cell function in AD is still far from clear, though it plays an important role in immunotherapy. The aim of this study was to determine peripheral T-cell reactivity in AD patients and in an AD mouse model. Mitogenic activation via ligation of the T-cell receptor (TCR) with PHA-L was measured in T lymphocytes from AD patients and Thy1(APP751SL) × HMG(PS1M146L)-transgenic mice (APP × PS1). In order to uncover failures in TCR signaling, the TCR was also bypassed by PMA and ionomycin treatment. All patients were sporadic late onset cases and the transgenic mice expressed no mutant APP in lymphocytes, so that direct interactions of mutant APP on T-cell function can be excluded. CD4+ and CD8+ T-cell showed increased reactivity (tyrosine phosphorylation, CD69 expression, and proliferation) in AD, while APP × PS1 transgenic mice displayed hyporeactive CD8+ T-cells after TCR ligation. Increased levels of CD8+ T memory cells and down regulation of CD8 receptor were found in AD and the animal model. Anergic TCR uncoupling was associated with loss of MAPK signaling (p38, ERK1 and ERK2) in APP × PS1. Our data implicate the generation of reactive memory T-cell in AD and of anergic memory T-cells in transgenic mice and should be taken into concern when designing immunotherapy. [ABSTRACT FROM AUTHOR]

The article examines the neurological changes which contribute to working memory (WM) deficits during perceptual and cognitive stages of schizophrenia through monitoring of neural activity during WM encoding and retrieval with event related potential (ERP) components P1, P3a, P370 and P570 as well as data from functional magnetic resonance imaging (fMRI). Results show that P1 is significant to successful WM encoding while early visual deficits and deficits in later-memory related process contribute to impaired WM in schizophrenia.

Recent theoretical and empirical research on schizophrenia converges on the notion that core aspects of the pathophysiology of the disorder may arise from a dysfunction in the coordination of distributed neural activity. Synchronization of neural responses in the β-band (15-30 Hz) and δ-band range (30-80 Hz) has been implicated as a possible neural substrate for dysfunctional coordination in schizophrenia. To test this hypothesis, we examined the electroencephalography (EEG) activity in 19 patients with a Diagnostic and Statistical Manual of Mental Disorder, edition IV criteria, diagnosis of schizophrenia and 19 healthy control subjects during a Gestalt perception task. EEG data were analyzed for phase synchrony and induced spectral power as an index of neural synchronization. Schizophrenia patients were impaired significantly in the detection of images that required the grouping of stimulus elements into coherent object representations. This deficit was accompanied by longer reaction times in schizophrenia patients. Deficits in Gestalt perception in schizophrenia patients were associated with reduced phase synchrony in the β-band (20-30 Hz), whereas induced spectral power in the δ-band (40-70 Hz) was mainly intact. Our findings suggest that schizophrenia patients are impaired in the long-range synchronization of neural responses, which may reflect a core deficit in the coordination of neural activity and underlie the specific cognitive dysfunctions associated with the disorder. [ABSTRACT FROM AUTHOR]

Background: In a previous functional magnetic resonance imaging study, the authors succeeded in demonstrating the activation of Heschl’s gyrus during auditory hallucinations (AH). Objectives: This study aims to treat AH specifically by repetitive transcranial magnetic stimulation (rTMS). Methods: 16 patients with AH were included in a randomized, cross-over, sham-controlled trial. 1 Hz rTMS was administered over the left and right temporo-parietal cortex and sham position, respectively, on 5 consecutive days; 900 stimuli each, strength 100% of motor threshold. Using the Psychotic Symptom Rating Scales (PSYRATS), the hallucinations during the stimulation periods and 4-week follow-ups were quantified. Electroencephalograms (EEG) were acquired before and after each period. Results: Treatment responses were observed after left hemisphere rTMS only. The 5 patients who showed a response did so already after 2 days. However, group mean hallucination scores did not differ across treatment conditions. No significant changes were found in EEG after rTMS. Conclusions: A subgroup of patients suffering from AH benefits soon after treatment start from rTMS over the left superior temporal gyrus as revealed by the decrease of AH scores compared to right-sided and sham procedures. Copyright © 2006 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

There is a lack of psychological autopsy studies assessing the influence of axis I disorders on axis II disorders as risk factors for suicide. Therefore, we investigated the association between personality disorders, axis I disorders, and suicide. Psychiatric disorders were evaluated by a semi–structured interview including the Structured Clinical Interview for DSM–IV Axis I (SCID–I) and Personality Disorders (SCID–II) in 163 completed suicides (mean age 49.6 ± 19.3 years; 64.4% men) and by personal interview in 396 populationbased control persons (mean age 51.6 ± 17.0 years; 55.8% men). In both genders, suicides significantly more often had personality disorders of all clusters than controls, also after adjustment for axis I disorders (p < 0.001, each). In addition, alcohol–related disorders, major depression, and co–occurrence of personality disorders of more than one cluster (men: OR = 16.13; women: OR = 20.43) remained independent predictors for suicide in both genders,"pure" cluster B personality disorders only in women and "pure" cluster C personality disorders only in men. In both genders, co–occurrence of personality disorders of more than one cluster contributed to risk of completed suicide after control for axis I psychiatric disorders and has to be considered as an independent risk factor for suicide. [ABSTRACT FROM AUTHOR]

We used the combination of functional magnetic resonance imaging and event-related potentials to decompose the processing stages (mental chronometry) of working memory retrieval. Our results reveal an early transient activation of inferotemporal cortex, which was accompanied by the onset of a sustained activation of posterior parietal cortex. We furthermore observed late transient responses in ventrolateral prefrontal cortex and late sustained activity in medial frontal and premotor areas. We propose that these neural signatures reflect the cognitive stages of task processing, perceptual evaluation (inferotemporal cortex), storage buffer operations (posterior parietal cortex), active retrieval (ventrolateral prefrontal cortex), and action selection (medial frontal and premotor cortex). This is also supported by their differential temporal contribution to specific subcomponents of the P300 cognitive potential. [ABSTRACT FROM AUTHOR]

Screening instruments for detection of alcohol consumption, abuse, and dependence for use in psychological autopsy studies with case control design are not validated. Therefore, interrater and test-retest reliability of the Luebeck Alcohol Dependence and Abuse Screening Test (LAST) and the usability of this test for the psychological autopsy method were investigated. Alcohol consumption was evaluated by a semi-structured interview including the Structured Clinical Interview for DSM-IV Axis I (SCID-I) and the LAST in 163 completed suicides (mean age 49.6 ± 19.3 years; 64.4% men) and by personal interview in 396 population-based controls (mean age 51.6 ± 17.0 years; 55.8% men). Of the controls, 35 were additionally assessed by interviewing informants; these results were compared with those generated by personal interview. Comparison of LAST scores by personal and informant’s interview of controls generated a Spearman correlation coefficient of 0.74 (P<0.0001). The LAST (7 item-version, cut-off of 2) revealed high sensitivity and specificity for alcohol abuse and dependence, in both controls and suicides. LAST scores were significantly associated with high, frequent, and hazardous alcohol consumption (P<0.001) in suicides. Our findings provide support for reliability and validity of identifying individuals with alcohol dependence and abuse obtained through the best-estimate method using the LAST. This 7-item questionnaire can be recommended as a useful tool for the psychological autopsy procedure in postmortem research. [ABSTRACT FROM AUTHOR]

The identification of specific genetic (presenilin-1 [PS1] and amyloid precursor protein [APP] mutations) and environmental factors responsible for Alzheimer’s disease (AD) has revealed evidence for a shared pathway of neuronal death. Moreover, AD-specific cell defects may be observed in many other nonneuronal cells (e.g., lymphocytes). Thus, lymphocytes may serve as a cellular system in which to study risk factors of sporadic, as well as genetic AD in vivo. The aim of our present study was to clarify whether lymphocytes bearing genetic or sporadic risk factors of AD share an increased susceptibility to cell death. Additionally we examined whether a cell type-specific vulnerability pattern was present and how normal aging, the main risk factor of sporadic AD, contributes to changes in susceptibility to cell death. Here, we report that lymphocytes affected by sporadic or genetic APP and PS1 AD risk factors share an increased vulnerability to cell death and exhibit a similar cell type-specific pattern, given that enhanced vulnerability was most strongly developed in the CD4+ T-cell subtype. In this paradigm, sporadic risk factors revealed the highest impact on cell type-specific sensitivity of CD4+ T cells to apoptosis. In contrast, normal aging results in an increased susceptibility to apoptosis of both, CD4+ and CD8+ T cells. [ABSTRACT FROM AUTHOR]

P300 is an event-related potential that is elicited by an oddball paradigm. In several neuropsychiatric diseases, differences in latencies and amplitude compared to healthy subjects have been reported. Because of its clinical significance, several investigations have tried to elucidate the intracranial origins of the P300 component. In the present study we could demonstrate a network of P300 generators. Investigated were 15 healthy subjects with an acoustical oddball paradigm within a fMRI block design, which enabled us to exclude attention of acoustical processing effects. The inferior and middle frontal, superior temporal, lower parietal cortex, the insula and the anterior cingulum were significantly activated symmetrical in both hemispheres. [ABSTRACT FROM AUTHOR]

Rationale: The intensity dependence of the auditory evoked potentials (AEP) has been suggested to be a specific biological marker of central serotonergic activity. Objective: While previous studies used circumstantial evidence to support this hypothesis, we manipulated (decreased) cerebral levels of serotonin directly by using tryptophan depletion. Methods: Twelve healthy young subjects were investigated using placebo and two different amino acid mixtures in a double blind cross over design on three different occasions. AEPs recorded during tryptophan depletion were analyzed by dipole analysis and regional sources using methods published in the literature. Results: For none of the mixtures a significant effect of tryptophan depletion was found. There was a trend towards reduced intensity dependency after tryptophan depletion, especially in the right hemisphere. This reduction correlated with the amount of reduced tryptophan in plasma. Conclusions: The results indicate, in contrast to earlier indirect studies, that the intensity dependence of AEPs is not a specific marker of central serotonergic activity. [ABSTRACT FROM AUTHOR]

Topographic brain mapping of EEG and evoked potentials permits the display of spontaneous and event-related activity of the brain. This new method is superior to conventional polygraphy because of the topographic approach which delineates structural and functional brain lesions. Data from 16 to 20 scalp electrodes were evaluated. Not only spontaneous EEG but also EEG during various testing conditions which activated particular brain regions was measured. For EEG fast Fourier transformation (FFT) was used for mapping. For late evoked potentials (VEP, AEP, SEP and P300) a single value representing the amplitude of EP at each 2-ms poststimulus latency point was used. Statistical techniques (Students'-test, correlation coefficient) were used to render the regions where a clinical population differs from normal subjects. The results show abnormalities of EGG and EP in patients with psychiatric and neurological diseases. [ABSTRACT FROM AUTHOR]

Two letters to the editor are presented including one in response to the article "Intravenous immunoglobulin treatment of the complex regional pain syndrome: a randomized trial" in the 2010 issue and the other in response by Andreas Goebel and colleagues to an editorial to their article.

The article presents an obituary for Helmut Beckmann, a physician and professor at the Ludwig-Maximilians University in Munich.