Cognitive Underperformance in a Mixed Neuropsychiatric Sample at Diagnostic Evaluation of Adult ADHD

(1) Background: The clinical assessment of attention-deficit/hyperactivity disorder (ADHD) in adulthood is known to show non-trivial base rates of noncredible performance and requires thorough validity assessment. (2) Objectives: The present study estimated base rates of noncredible performance in clinical evaluations of adult ADHD on one or more of 17 embedded validity indicators (EVIs). This study further examines the effect of the order of test administration on EVI failure rates, the association between cognitive underperformance and symptom overreporting, and the prediction of cognitive underperformance by clinical information. (3) Methods: A mixed neuropsychiatric sample (N = 464, ADHD = 227) completed a comprehensive neuropsychological assessment battery on the Vienna Test System (VTS; CFADHD). Test performance allows the computation of 17 embedded performance validity indicators (PVTs) derived from eight different neuropsychological tests. Further, all participants completed several self- and other-report symptom rating scales assessing depressive symptoms and cognitive functioning. The Conners' Adult ADHD Rating Scale and the Beck Depression Inventory-II were administered to derive embedded symptom validity measures (SVTs). (4) Results and conclusion: Noncredible performance occurs in a sizeable proportion of about 10% up to 30% of individuals throughout the entire battery. Tests for attention and concentration appear to be the most adequate and sensitive for detecting underperformance. Cognitive underperformance represents a coherent construct and seems dissociable from symptom overreporting. These results emphasize the importance of performing multiple PVTs, at different time points, and promote more accurate calculation of the positive and negative predictive values of a given validity measure for noncredible performance during clinical assessments. Future studies should further examine whether and how the present results stand in other clinical populations, by implementing rigorous reference standards of noncredible performance, characterizing those failing PVT assessments, and differentiating between underlying motivations.

Networks of Neuropsychological Functions in the Clinical Evaluation of Adult ADHD

This study applied network analysis to explore the relations between neuropsychological functions of individuals in the clinical evaluation of attention-deficit/hyperactivity disorder (ADHD) in adulthood. A total of 319 participants from an outpatient referral context, that is, 173 individuals with ADHD (ADHD group) and 146 individuals without ADHD (n-ADHD group), took part in this study and completed a comprehensive neuropsychological assessment. A denser network with stronger global connectivity was observed in the ADHD group compared to the n-ADHD group. The strongest connections were consistent in both networks, that is, the connections between selective attention and vigilance, and connections between processing speed, fluency, and flexibility. Further centrality estimation revealed attention-related variables to have the highest expected influence in both networks. The observed relationships between neuropsychological functions, and the high centrality of attention, may help identify neuropsychological profiles that are specific to ADHD and optimize neuropsychological assessment and treatment planning of individuals with cognitive impairment.

Ceramide levels in blood plasma correlate with major depressive disorder severity and its neutralization abrogates depressive behavior in mice

Major depressive disorder (MDD) is a severe disease of unknown pathogenesis that will affect ∼10% of people during their lifetime. Therapy for MDD requires prolonged treatment and often fails, predicating a need for novel treatment strategies. Here, we report increased ceramide levels in the blood plasma of MDD patients and in murine stress-induced models of MDD. These blood plasma ceramide levels correlated with the severity of MDD in human patients and were independent of age, sex, or body mass index. In addition, intravenous injection of anti-ceramide antibodies or neutral ceramidase rapidly abrogated stress-induced MDD, and intravenous injection of blood plasma from mice with MDD induced depression-like behavior in untreated mice, which was abrogated by ex vivo pre-incubation of the plasma with anti-ceramide antibodies or ceramidase. Mechanistically, we demonstrate that ceramide accumulated in endothelial cells of the hippocampus of stressed mice, evidenced by the quantitative measurement of ceramide in purified hippocampus endothelial cells. We found ceramide inhibited the activity of phospholipase D (PLD) in endothelial cells in vitro and in the hippocampus in vivo and thereby decreased phosphatidic acid in the hippocampus. Finally, we show intravenous injection of PLD or phosphatidic acid abrogated MDD, indicating the significance of this pathway in MDD pathogenesis. Our data indicate that ceramide controls PLD activity and phosphatidic acid formation in hippocampal endothelial cells and thereby mediates MDD. We propose that neutralization of plasma ceramide could represent a rapid-acting targeted treatment for MDD.

It Takes Time: Vigilance and Sustained Attention Assessment in Adults with ADHD

Objectives: The present study compares the utility of eight different tests of vigilance and sustained attention in the neuropsychological examination of adults with Attention-deficit/hyperactivity disorder (ADHD). Methods: Thirty-one adults diagnosed with ADHD performed eight tests for vigilance and sustained attention, spread over three assessment days. Results: Adults with ADHD showed cognitive impairments in most tests and test variables, even though their sensitivity differed greatly. No specific type of test variable stands out to be the most sensitive, and no evidence for a differential deterioration of performance over time was observed. Conclusion: This study underscores the role of vigilance and sustained attention tests in the assessment of adult ADHD. It is further concluded that summary scores over the entire test duration are sufficient, but that all variables of a test should be considered. Finally, we hypothesize that reassessment on a different day may benefit a more accurate clinical assessment of adults with ADHD, in order to adequately take intraindividual fluctuations and limitations regarding test reliability into account.

Problems in measuring the JTC-bias in patients with psychotic disorders with the fish task: a secondary analysis of a baseline assessment of a randomized controlled trial

BACKGROUND

The jumping to conclusions bias (JTC) is considered to be an important causal factor in theoretical models for the formation and maintenance of delusions. However, recent meta-analytic findings show a rather equivocal pattern of results regarding associations between JTC and delusions. Thus, the present study aims to investigate in a large sample whether the JTC-bias is more pronounced in patients with psychotic disorders in comparison to controls and whether the JTC bias is associated with a more severe delusional conviction, persecutory delusions, and positive symptoms in general.

METHODS

Patients with psychotic disorders (n = 300) enrolled in a therapy trial and healthy controls (n = 51) conducted a variant of the beads task (fish task) as a measure for the JTC-bias at the start of the trial. Further, clinical interviews were used to assess patients' delusional severity and delusional conviction.

RESULTS

There were no statistically significant differences between patients with psychotic disorders (with 53% displaying the JTC-bias) and controls (41%). Furthermore, there were no statistically significant correlations between JTC measures and persecutory delusions, delusional conviction, and positive symptoms.

CONCLUSIONS

We found no differences in JTC between patients with psychotic disorders and healthy controls, which is in part in line with meta-analytic findings using a wide range of JTC task variants. Interestingly, patients with psychotic disorders displayed JTC rates commonly found in the literature, while healthy control subjects showed an unexpectedly high level of JTC. The task variant we used in the present study (fish task) is discussed as a potential reason for our results, as it may induce a more deliberative reasoning style in controls as compared to the traditional beads task. Furthermore, possible implications for the measurement of the JTC-bias, in general, are discussed.

TRIAL REGISTRATION

ISRCTN29242879 ( isrctn.com ), date of registration: April 12th 2006, retrospectively registered.

Accuracy and reproducibility of automated white matter hyperintensities segmentation with lesion segmentation tool: A European multi-site 3T study

Brain vascular damage accumulate in aging and often manifest as white matter hyperintensities (WMHs) on MRI. Despite increased interest in automated methods to segment WMHs, a gold standard has not been achieved and their longitudinal reproducibility has been poorly investigated. The aim of present work is to evaluate accuracy and reproducibility of two freely available segmentation algorithms. A harmonized MRI protocol was implemented in 3T-scanners across 13 European sites, each scanning five volunteers twice (test-retest) using 2D-FLAIR. Automated segmentation was performed using Lesion segmentation tool algorithms (LST): the Lesion growth algorithm (LGA) in SPM8 and 12 and the Lesion prediction algorithm (LPA). To assess reproducibility, we applied the LST longitudinal pipeline to the LGA and LPA outputs for both the test and retest scans. We evaluated volumetric and spatial accuracy comparing LGA and LPA with manual tracing, and for reproducibility the test versus retest. Median volume difference between automated WMH and manual segmentations (mL) was -0.22[IQR = 0.50] for LGA-SPM8, -0.12[0.57] for LGA-SPM12, -0.09[0.53] for LPA, while the spatial accuracy (Dice Coefficient) was 0.29[0.31], 0.33[0.26] and 0.41[0.23], respectively. The reproducibility analysis showed a median reproducibility error of 20%[IQR = 41] for LGA-SPM8, 14% [31] for LGA-SPM12 and 10% [27] with the LPA cross-sectional pipeline. Applying the LST longitudinal pipeline, the reproducibility errors were considerably reduced (LGA: 0%[IQR = 0], p < 0.001; LPA: 0% [3], p < 0.001) compared to those derived using the cross-sectional algorithms. The DC using the longitudinal pipeline was excellent (median = 1) for LGA [IQR = 0] and LPA [0.02]. LST algorithms showed moderate accuracy and good reproducibility. Therefore, it can be used as a reliable cross-sectional and longitudinal tool in multi-site studies.

Amygdalar nuclei and hippocampal subfields on MRI: Test-retest reliability of automated volumetry across different MRI sites and vendors

BACKGROUND

The amygdala and the hippocampus are two limbic structures that play a critical role in cognition and behavior, however their manual segmentation and that of their smaller nuclei/subfields in multicenter datasets is time consuming and difficult due to the low contrast of standard MRI. Here, we assessed the reliability of the automated segmentation of amygdalar nuclei and hippocampal subfields across sites and vendors using FreeSurfer in two independent cohorts of older and younger healthy adults.

METHODS

Sixty-five healthy older (cohort 1) and 68 younger subjects (cohort 2), from the PharmaCog and CoRR consortia, underwent repeated 3D-T1 MRI (interval 1-90 days). Segmentation was performed using FreeSurfer v6.0. Reliability was assessed using volume reproducibility error (ε) and spatial overlapping coefficient (DICE) between test and retest session.

RESULTS

Significant MRI site and vendor effects (p ​< ​.05) were found in a few subfields/nuclei for the ε, while extensive effects were found for the DICE score of most subfields/nuclei. Reliability was strongly influenced by volume, as ε correlated negatively and DICE correlated positively with volume size of structures (absolute value of Spearman's r correlations >0.43, p ​< ​1.39E-36). In particular, volumes larger than 200 ​mm³ (for amygdalar nuclei) and 300 ​mm³ (for hippocampal subfields, except for molecular layer) had the best test-retest reproducibility (ε ​< ​5% and DICE ​> ​0.80).

CONCLUSION

Our results support the use of volumetric measures of larger amygdalar nuclei and hippocampal subfields in multisite MRI studies. These measures could be useful for disease tracking and assessment of efficacy in drug trials.

Theory of mind, emotion recognition, delusions and the quality of the therapeutic relationship in patients with psychosis - a secondary analysis of a randomized-controlled therapy trial

BACKGROUND

Cognitive models of psychosis postulate an important role of Theory of mind (ToM) in the formation and maintenance of delusions, but research on this plausible conjecture has gathered conflicting findings. In addition, it is still an open question whether problems in emotion recognition (ER) are associated with delusions. We examined the association of problems in ToM and ER with different aspects of delusions in a large sample of patients with psychosis enrolled in a therapy trial. This also enabled us to explore the possible impact of ToM and ER on one part of patients' social life: the quality of their therapeutic relationship.

METHODS

Patients with psychotic disorders and delusions and/or hallucinations (n = 185) and healthy controls (n = 48) completed a ToM picture sequencing task and an ER task. Subsequently, patients were enrolled in a randomized-controlled Cognitive Behavior Therapy (CBT) trial (ISRCTN29242879). Patients and therapists rated the quality of the therapeutic relationship during the first five sessions of therapy.

RESULTS

In comparison to controls, patients were impaired in both ToM and ER. Patients with deficits in ER experienced more severe delusional distress, whereas ToM problems were not related to delusions. In addition, deficits in ER predicted a less favorable therapeutic relationship and interactional problems viewed by the therapist. Impaired ER also moderated (increased) the negative influence of delusions on the therapeutic relationship and interactional difficulties viewed by the therapist.

CONCLUSIONS

Cognitive models on the formation and maintenance of delusions should consider ER as a potential candidate that might be related to the formation and maintenance of delusional distress, whereas problems in ToM might not be directly related to delusions and secondary dimensions of delusions. In addition, problems in ER in patients with psychosis might have an impact on the quality of the therapeutic relationship and patients with problems in ER are more likely to be viewed as problematic by their therapists. Nevertheless, training ER might be a way to improve the quality of the therapeutic relationship and potentially the effectiveness of CBT or other interventions for patients with psychosis.

Negative schemata about the self and others and paranoid ideation in at-risk states and those with persisting positive symptoms

BACKGROUND

The objective of this study is to test the conflicting theories concerning the association of negative self and other schemata and paranoid ideation.

METHODS

A risk-based approach, including risk stratification, is used to gain insight into the association of the negative self and other schemata that may be shared by individuals or differentiate between individuals at clinical high risk (CHR) for a first-episode psychosis and those with full-blown psychosis. The dataset includes a sample of individuals at CHR (n = 137) and a sample of individuals with persisting positive symptoms (PPS, n = 211). The CHR sample was subdivided according to a prognostic index yielding 4 CHR sub-classes with increasing risk for transition to psychosis.

RESULTS

Negative beliefs about the self were associated with paranoid ideation in CHR and a lower risk state. In the highest risk state and full-blown psychosis, there is an association with negative beliefs about others.

CONCLUSION

These findings are in line with theories suggesting a switch from a predominantly activated negative self-schema to a malevolent others-schema in association with paranoid ideation along the risk-continuum. However, due to methodological limitations these results should be replicated by future studies.

Cognitive bias modification as an add-on treatment in clinical depression: Results from a placebo-controlled, single-blinded randomized control trial

BACKGROUND

Only 60% of depressed patients respond sufficiently to treatment, so there is a dire need for novel approaches to improve treatment effects. Cognitive Bias Modification (CBM) may be an effective and easily implemented computerized add-on to treatment-as-usual. Therefore, we investigated the effects of a positivity-attention training and a positivity-approach training compared to control trainings.

METHODS

In a blinded randomized-controlled design, 139 depressed inpatients received either the CBM Attention Dot-Probe Training (DPT) or the CBM Approach-Avoidance Training (AAT), next to treatment as usual. N = 121 finished all four training sessions. Both trainings had an active and a control condition. In both active conditions, patients were trained to preferentially process generally positive pictures over neutral pictures. Depressive symptom severity was assessed before and after CBM, and positivity bias was measured at the start and end of each session.

RESULTS

Clinician-rated depressive symptom severity decreased more in patients who received the active condition of the DPT or the AAT compared to patients in the control conditions. Significant change in positivity bias was found for the DPT (not the AAT), but did not mediate the effect of the training on depressive symptoms.

CONCLUSIONS

The results suggest that both types of CBM (i.e., DPT and AAT) may provide a fitting add-on treatment option for clinical depression. The working mechanisms and optimal dose of CBM trainings, plus their possible combination, should be examined in more detail.

Neural Mechanisms Underlying Affective Theory of Mind in Violent Antisocial Personality Disorder and/or Schizophrenia

Among violent offenders with schizophrenia, there are 2 sub-groups, one with and one without, conduct disorder (CD) and antisocial personality disorder (ASPD), who differ as to treatment response and alterations of brain structure. The present study aimed to determine whether the 2 groups also differ in Theory of Mind and neural activations subsuming this task. Five groups of men were compared: 3 groups of violent offenders-schizophrenia plus CD/ASPD, schizophrenia with no history of antisocial behavior prior to illness onset, and CD/ASPD with no severe mental illness-and 2 groups of non-offenders, one with schizophrenia and one without (H). Participants completed diagnostic interviews, the Psychopathy Checklist Screening Version Interview, the Interpersonal Reactivity Index, authorized access to clinical and criminal files, and underwent functional magnetic resonance imaging while completing an adapted version of the Reading-the-Mind-in-the-Eyes Task (RMET). Relative to H, nonviolent and violent men with schizophrenia and not CD/ASPD performed more poorly on the RMET, while violent offenders with CD/ASPD, both those with and without schizophrenia, performed similarly. The 2 groups of violent offenders with CD/ASPD, both those with and without schizophrenia, relative to the other groups, displayed higher levels of activation in a network of prefrontal and temporal-parietal regions and reduced activation in the amygdala. Relative to men without CD/ASPD, both groups of violent offenders with CD/ASPD displayed a distinct pattern of neural responses during emotional/mental state attribution pointing to distinct and comparatively successful processing of social information.

Attenuated Readiness Potential in the Absence of Executive Dysfunction in Adults With ADHD

OBJECTIVE

Patients with ADHD display a decreased contingent negative variation in Go/NoGo tasks. It is unclear whether the attenuation is due to deficits of executive function or to disorder of motor planning. The readiness potential (RP) recorded during self-initiated movements could cast light on this question.

METHOD

RP was recorded in 25 stably medicated adult ADHD patients and 21 healthy controls matched for age, education, and verbal IQ. Participants also completed neuropsychological tests of executive function.

RESULTS

Compared with healthy controls, ADHD patients showed significantly diminished RP peaks and also decreased negativity in preparation of the movement at frontal locations. There were no significant group differences with regard to tests of executive function.

CONCLUSION

In adults with ADHD, deficits of motor organization are also manifest in situations not involving external stimulus processing. The attenuated RP occurred in the absence of executive dysfunction. Results are consistent with partial independence between motor and executive dysfunction in ADHD.

Association between CSF biomarkers, hippocampal volume and cognitive function in patients with amnestic mild cognitive impairment (MCI)

Few studies have examined the relationship between CSF and structural biomarkers, and cognitive function in MCI. We examined the relationship between cognitive function, hippocampal volume and cerebrospinal fluid (CSF) Aβ₄₂ and tau in 145 patients with MCI. Patients were assessed on cognitive tasks from the Cambridge Neuropsychological Test Automated Battery (CANTAB), the Geriatric Depression Scale and the Functional Activities Questionnaire. Hippocampal volume was measured using magnetic resonance imaging (MRI), and CSF markers of Aβ₄₂, tau and p-tau₁₈₁ were also measured. Worse performance on a wide range of memory and sustained attention tasks were associated with reduced hippocampal volume, higher CSF tau and p-tau₁₈₁ and increased tau/Aβ₄₂ ratio. Memory tasks were also associated with lower ability to conduct functional activities of daily living, providing a link between AD biomarkers, memory performance and functional outcome. These results suggest that biomarkers of Aβ and tau are strongly related to cognitive performance as assessed by the CANTAB, and have implications for the early detection and characterization of incipient AD.

Aerobic Activity in the Healthy Elderly Is Associated with Larger Plasticity in Memory Related Brain Structures and Lower Systemic Inflammation

Cognitive abilities decline over the time course of our life, a process, which may be mediated by brain atrophy and enhanced inflammatory processes. Lifestyle factors, such as regular physical activities have been shown to counteract those noxious processes and are assumed to delay or possibly even prevent pathological states, such as dementing disorders. Whereas the impact of lifestyle and immunological factors and their interactions on cognitive aging have been frequently studied, their effects on neural parameters as brain activation and functional connectivity are less well studied. Therefore, we investigated 32 healthy elderly individuals (60.4 ± 5.0 SD; range 52–71 years) with low or high level of self-reported aerobic physical activity at the time of testing. A higher compared to a lower level in aerobic physical activity was associated with an increased encoding related functional connectivity in an episodic memory network comprising mPFC, thalamus, hippocampus precuneus, and insula. Moreover, encoding related functional connectivity of this network was associated with decreased systemic inflammation, as measured by systemic levels of interleukin 6.

Occipital event-related potentials to addiction-related stimuli in detoxified patients with alcohol dependence, and their association with three-month relapse

BACKGROUND

Understanding the biological underpinnings of relapse in alcohol dependency is a major issue in addiction research. Based on recent evidence regarding the relevance of occipital visual evoked response potentials (ERPs) in addiction research, and its significance for relapse research, we assessed occipital ERPs to alcohol- and non-alcohol-related stimuli in recently detoxified patients and controls.

METHODS

Thirty recently detoxified patients with alcohol addiction, and 31 healthy control subjects, were assessed in a Go and a NoGo condition, each using three visual stimuli: tea, juice and beer. In the "Go" condition, subjects had to respond to the juice (12.5 %) and the beer stimulus (12.5 %), and ignore the tea picture (75 %). In the "NoGo" condition, subjects had to respond to the tea picture (75 %) and ignore the juice and the beer picture (12.5 % each). The subjects' EEGs were analyzed with regard to the occipital P100 and N170 ERP components. Patients were then evaluated for relapse 3 months after this initial assessment.

RESULTS

P100 amplitudes differed between conditions and between stimuli, and we found a condition x electrode interaction. However, none of these P100 results involved group or relapse-status effects. N170 amplitudes in patients were elevated as compared to controls. Additionally, patients' heightened N170 amplitudes in response to the alcohol-related (beer) stimulus were found only under the NoGo condition, where subjects had to react to the frequent tea stimulus and ignore the beer and the juice stimuli, thus resulting in a condition x stimulus x group interaction. Patients reporting relapse in a 3-month follow-up assessment showed larger NoGo N170 alcohol cue-related ERP amplitudes and increased depression scores as compared to patients who stayed abstinent. Depression was related to shortened P100 latencies in patients, but unrelated to the N170 NoGo cue-reactivity effect.

CONCLUSIONS

Our results indicate a sensitivity of occipital ERPs to addiction-related stimuli when these act as non-targets. Recently detoxified patients may be vulnerable to addiction-related cues when these occur outside the focus of directed attention, thereby circumventing intentional control processes. Furthermore, ERPs to addiction-related stimuli may be useful as a predictor of abstinence success in recently detoxified patients.

Data on deviance predictability in the assessment of mismatch negativity in patients with schizophrenia

We investigated the MMN at electrode Fz to 12% temporally predictable or unpredictable duration decrement deviant stimuli in 29 healthy controls and 31 schizophrenia patients. With a stimulus onset asynchronicity of 500 ms in the regular predictable condition, a deviant occurred every 4 s while it varied randomly in the unpredictable condition. Here we report detailed data tables and multivariate analysis of variance results (MANOVA) on MMN, P3a and standard ERP data including details on follow-up analyses. An extended figure shows MMN difference curves and averages to standard and deviant stimuli in both experimental conditions and subject groups.

Test-retest reliability of the default mode network in a multi-centric fMRI study of healthy elderly: Effects of data-driven physiological noise correction techniques

Understanding how to reduce the influence of physiological noise in resting state fMRI data is important for the interpretation of functional brain connectivity. Limited data is currently available to assess the performance of physiological noise correction techniques, in particular when evaluating longitudinal changes in the default mode network (DMN) of healthy elderly participants. In this 3T harmonized multisite fMRI study, we investigated how different retrospective physiological noise correction (rPNC) methods influence the within-site test-retest reliability and the across-site reproducibility consistency of DMN-derived measurements across 13 MRI sites. Elderly participants were scanned twice at least a week apart (five participants per site). The rPNC methods were: none (NPC), Tissue-based regression, PESTICA and FSL-FIX. The DMN at the single subject level was robustly identified using ICA methods in all rPNC conditions. The methods significantly affected the mean z-scores and, albeit less markedly, the cluster-size in the DMN; in particular, FSL-FIX tended to increase the DMN z-scores compared to others. Within-site test-retest reliability was consistent across sites, with no differences across rPNC methods. The absolute percent errors were in the range of 5-11% for DMN z-scores and cluster-size reliability. DMN pattern overlap was in the range 60-65%. In particular, no rPNC method showed a significant reliability improvement relative to NPC. However, FSL-FIX and Tissue-based physiological correction methods showed both similar and significant improvements of reproducibility consistency across the consortium (ICC = 0.67) for the DMN z-scores relative to NPC. Overall these findings support the use of rPNC methods like tissue-based or FSL-FIX to characterize multisite longitudinal changes of intrinsic functional connectivity. Hum Brain Mapp 37:2114-2132, 2016. © 2016 Wiley Periodicals, Inc.

The effect of deviance predictability on mismatch negativity in schizophrenia patients

Mismatch negativity (MMN) is an electrophysiological index of prediction error processing and recently has been considered an endophenotype marker in schizophrenia. While the prediction error is a core concept in the MMN generation, predictability of deviance occurrence has rarely been assessed in MMN research and in schizophrenia patients. We investigated the MMN to 12% temporally predictable or unpredictable duration decrement deviant stimuli in two runs in 29 healthy controls and 31 schizophrenia patients. We analyzed MMN amplitudes and latencies and its associations with clinical symptoms at electrode Fz. With a stimulus onset asynchronicity of 500 ms in the regular predictable condition, a deviant occurred every 4s while it varied randomly in the unpredictable condition. In the random condition we found diminished MMN amplitudes in patients which normalized in the regular deviance condition, resulting in an analysis of variance main effect of predictability and a predictability x group interaction. Deviance predictability did not affect the MMN of control subjects and we found no relevant results with regard to MMN latencies. Our results indicate that MMN amplitudes in patients normalize to the level of the control subjects in the case of a temporally fixed regular deviant. In schizophrenia patients the detection of deviance is basically intact. However, the temporal uncertainty of deviance occurrence may be of substantial relevance to the highly replicated MMN deficit in schizophrenia patients.

Longitudinal reproducibility of automatically segmented hippocampal subfields: A multisite European 3T study on healthy elderly

Recently, there has been an increased interest in the use of automatically segmented subfields of the human hippocampal formation derived from magnetic resonance imaging (MRI). However, little is known about the test-retest reproducibility of such measures, particularly in the context of multisite studies. Here, we report the reproducibility of automated Freesurfer hippocampal subfields segmentations in 65 healthy elderly enrolled in a consortium of 13 3T MRI sites (five subjects per site). Participants were scanned in two sessions (test and retest) at least one week apart. Each session included two anatomical 3D T1 MRI acquisitions harmonized in the consortium. We evaluated the test-retest reproducibility of subfields segmentation (i) to assess the effects of averaging two within-session T1 images and (ii) to compare subfields with whole hippocampus volume and spatial reliability. We found that within-session averaging of two T1 images significantly improved the reproducibility of all hippocampal subfields but not that of the whole hippocampus. Volumetric and spatial reproducibility across MRI sites were very good for the whole hippocampus, CA2-3, CA4-dentate gyrus (DG), subiculum (reproducibility error∼2% and DICE > 0.90), good for CA1 and presubiculum (reproducibility error ∼ 5% and DICE ∼ 0.90), and poorer for fimbria and hippocampal fissure (reproducibility error ∼ 15% and DICE < 0.80). Spearman's correlations confirmed that test-retest reproducibility improved with volume size. Despite considerable differences of MRI scanner configurations, we found consistent hippocampal subfields volumes estimation. CA2-3, CA4-DG, and sub-CA1 (subiculum, presubiculum, and CA1 pooled together) gave test-retest reproducibility similar to the whole hippocampus. Our findings suggest that the larger hippocampal subfields volume may be reliable longitudinal markers in multisite studies.

Why do bad things happen to me? Attributional style, depressed mood, and persecutory delusions in patients with schizophrenia

Theoretical models postulate an important role of attributional style (AS) in the formation and maintenance of persecutory delusions and other positive symptoms of schizophrenia. However, current research has gathered conflicting findings. In a cross-sectional design, patients with persistent positive symptoms of schizophrenia (n = 258) and healthy controls (n = 51) completed a revised version of the Internal, Personal and Situational Attributions Questionnaire (IPSAQ-R) and assessments of psychopathology. In comparison to controls, neither patients with schizophrenia in general nor patients with persecutory delusions (n = 142) in particular presented an externalizing and personalizing AS. Rather, both groups showed a "self-blaming" AS and attributed negative events more toward themselves. Persecutory delusions were independently predicted by a personalizing bias for negative events (beta = 0.197, P = .001) and by depression (beta = 0.152, P = .013), but only 5% of the variance in persecutory delusions could be explained. Cluster analysis of IPSAQ-R scores identified a "personalizing" (n = 70) and a "self-blaming" subgroup (n = 188), with the former showing slightly more pronounced persecutory delusions (P = .021). Results indicate that patients with schizophrenia and patients with persecutory delusions both mostly blamed themselves for negative events. Nevertheless, still a subgroup of patients could be identified who presented a more pronounced personalizing bias and more severe persecutory delusions. Thus, AS in patients with schizophrenia might be less stable but more determined by individual and situational characteristics that need further elucidation.

Mismatch negativity latency and cognitive function in schizophrenia

Background

The Mismatch Negativity (MMN) is an event-related potential (ERP) sensitive to early auditory deviance detection and has been shown to be reduced in schizophrenia patients. Moreover, MMN amplitude reduction to duration deviant tones was found to be related to functional outcomes particularly, to neuropsychological (working memory and verbal domains) and psychosocial measures. While MMN amplitude is thought to be correlated with deficits of early sensory processing, the functional significance of MMN latency remains unclear so far. The present study focused on the investigation of MMN in relation to neuropsychological function in schizophrenia.

Method

Forty schizophrenia patients and 16 healthy controls underwent a passive oddball paradigm (2400 binaural tones; 88% standards [1 kHz, 80 db, 80 ms], 11% frequency deviants [1.2 kHz], 11% duration deviants [40 ms]) and a neuropsychological test-battery. Patients were assessed with regard to clinical symptoms.

Results

Compared to healthy controls schizophrenia patients showed diminished MMN amplitude and shorter MMN latency to both deviants as well as an impaired neuropsychological test performance. Severity of positive symptoms was related to decreased MMN amplitude to duration deviants. Furthermore, enhanced verbal memory performance was associated with prolonged MMN latency to frequency deviants in patients.

Conclusion

The present study corroborates previous results of a diminished MMN amplitude and its association with positive symptoms in schizophrenia patients. Both, the findings of a shorter latency to duration and frequency deviants and the relationship of the latter with verbal memory in patients, emphasize the relevance of the temporal aspect of early auditory discrimination processing in schizophrenia.

Intensity Dependence of Auditory Evoked Potentials (IDAP) in Adult Attention Deficit/Hyperactivity (ADHD) Disorder

Intensity-dependent auditory evoked potentials (IDAP) were shown to be increased in highly impulsive individuals. As impulsivity is one of the core symptoms of attention deficit/hyperactivity disorder (ADHD), patients with ADHD were expected to exhibit an enhanced IDAP. Twenty-five ADHD patients taking methylphenidate and 21 healthy control participants were given diagnostic questionnaires including the Barratt Impulsivity Scale and IDAP was assessed with five-tone intensities. Amplitude, latency, and intensity slope of the N1, P2, and N1/P2 were determined. Contrary to our hypothesis, there was no significant group difference with regard to N1 amplitude and ADHD patients exhibited significantly lower P2 amplitude at high intensity and a flatter N1/P2 slope of the stimulus intensity function than healthy controls. Motor impulsivity, a subscale of the Barratt impulsivity scale, showed a significantly negative correlation with P2 amplitude within the ADHD group. The unexpected results could be due to the effect of methylphenidate.

Attenuated prefrontal activation during decision-making under uncertainty in schizophrenia: a multi-center fMRI study

Decisions are called decisions under uncertainty when either prior information is incomplete or the outcomes of the decision are unclear. Alterations in these processes related to decisions under uncertainty have been linked to delusions. In patients with schizophrenia, the underlying neural networks have only rarely been studied. We aimed to disentangle the neural correlates of decision-making and relate them to neuropsychological and psychopathological parameters in a large sample of patients with schizophrenia and healthy subjects. Fifty-seven patients and fifty-seven healthy volunteers from six centers had to either indicate via button-press from which of two bottles red or blue balls were drawn (decision-making under uncertainty condition), or indicate whether eight red balls had been presented (baseline condition) while BOLD signal was measured with fMRI. Patients based their decisions on less conclusive evidence and had decreased activations in the underlying neural network, comprising of medial and lateral frontal as well as parietal areas, as compared to healthy subjects. While current psychopathology was not correlated with brain activation, positive symptoms led to longer decision latencies in patients. These results suggest that decision-making under uncertainty in schizophrenia is affected by a complex interplay of aberrant neural activation. Furthermore, reduced neuropsychological functioning in patients was related to impaired decision-making and task performance was modulated by distinct positive symptoms.

Do different fairness contexts and facial emotions motivate 'irrational' social decision-making in major depression? An exploratory patient study

Although 'irrational' decision-making has been linked to depression, the contribution of biases in information processing to these findings remains unknown. To investigate the impact of cognitive biases and aberrant processing of facial emotions on social decision-making, we manipulated both context-related and emotion-related information in a modified Ultimatum Game. Unfair offers were (1) paired with different unselected alternatives, establishing the context in which an offer was made, and (2) accompanied by emotional facial expressions of proposers. Responder behavior was assessed in patients with major depressive disorder and healthy controls. In both groups alike, rejection rates were highest following unambiguous signals of unfairness, i.e. an angry proposer face or when an unfair distribution had deliberately been chosen over an equal split. However, depressed patients showed overall higher rejection rates than healthy volunteers, without exhibiting differential processing biases. This suggests that depressed patients were, as healthy individuals, basing their decisions on informative, salient features and differentiating between (i) fair and unfair offers, (ii) alternatives to unfair offers and (iii) proposers' facial emotions. Although more fundamental processes, e.g. reduced reward sensitivity, might underlie increased rejection in depression, the current study provides insight into mechanisms that shape fairness considerations in both depressed and healthy individuals.

Change of phase-solubility behavior by gamma-cyclodextrin derivatization

The effect of γ-cyclodextrin and its four derivatives on the solubility of progesterone in phosphate buffer pH 7.4 was investigated. γ-Cyclodextrin forms a complex precipitating from solution at low cyclodextrin concentrations. No precipitation of complexes was observed with the γ-cyclodextrin derivatives. This change in phase-solubility behavior is probably due to low crystallization tendencies of the derivatives.

[Determinants of direct cost in schizophrenia patients with persistent positive symptoms]

OBJECTIVE

To analyze direct costs and cost determinants in psychotic patients with persistent positive symptoms (PPS).

METHODS

A total of 330 patients with PPS were recruited via 6 university clinics and interviewed about service utilization in the previous 3 months. After monetary valuation, costs were analyzed via generalized linear mixed models with gamma distribution and log-link function to identify determinants of direct costs.

RESULTS

The mean costs were 7,065 € and resulted predominantly from psychiatric hospital care (63 %), assisted living (17 %) and complementary services (8 %). We found statistically significant associations between direct costs and an increasing score of the negative subscale of the Positive and Negative Syndrome Scale (+ 2,484 € per point, p < 0.001) and experiencing less than one social contact per week (- 2,272 €, p = 0.003).

CONCLUSION

PPS incurred substantial direct costs which primarily resulted from hospital treatment, and were strongly associated with symptom severity.

Structural brain alterations associated with schizophrenia preceded by conduct disorder: a common and distinct subtype of schizophrenia?

Conduct disorder (CD) prior to age 15 is a precursor of schizophrenia in a minority of cases and is associated with violent behavior through adulthood, after taking account of substance misuse. The present study used structural magnetic imaging to examine gray matter (GM) volumes among 27 men with schizophrenia preceded by CD (SZ+CD), 23 men with schizophrenia but without CD (SZ-CD), 27 men with CD only (CD), and 25 healthy (H) men. The groups with schizophrenia were similar in terms of age of onset and duration of illness, levels of psychotic symptoms, and medication. The 2 groups with CD were similar as to number of CD symptoms, lifelong aggressive behavior, and number of criminal convictions. Men with SZ+CD, relative to those with SZ-CD, displayed (1) increased GM volumes in the hypothalamus, the left putamen, the right cuneus/precuneus, and the right inferior parietal cortex after controlling for age, alcohol, and drug misuse and (2) decreased GM volumes in the inferior frontal region. Men with SZ+CD (relative to the SZ-CD group) and CD (relative to the H group) displayed increased GM volumes of the hypothalamus and the inferior and superior parietal lobes, which were not associated with substance misuse. Aggressive behavior, both prior to age 15 and lifetime tendency, was positively correlated with the GM volume of the hypothalamus. Thus, among males, SZ+CD represents a distinct subtype of schizophrenia. Although differences in behavior emerge in childhood and remain stable through adulthood, further research is needed to determine whether the differences in GM volumes result from abnormal neural development distinct from that of other males developing schizophrenia.

The impact of alcohol dependence on social brain function

The impact of alcoholism (ALC) or alcohol dependence on the neural mechanisms underlying cognitive and affective empathy (i.e. the different routes to understanding other people's minds) in schizophrenic patients and non-schizophrenic subjects is still poorly understood. We therefore aimed at determining the extent to which the ability to infer other people's mental states and underlying neural mechanisms were affected by ALC. We examined 48 men, who suffered either from ALC, schizophrenia, both disorders or none of these disorders, using functional magnetic resonance imaging while performing on a mind reading task that involves both cognitive and affective aspects of empathy. Using voxel-based morphometry, we additionally examined whether between-group differences in functional activity were associated with deficits in brain structural integrity. During mental state attribution, all clinical groups as compared with healthy controls exhibited poor performance as well as reduced right-hemispheric insular function with the highest error rate and insular dysfunction seen in the schizophrenic patients without ALC. Accordingly, both behavioral performance and insular functioning revealed schizophrenia × ALC interaction effects. In addition, schizophrenic patients relative to non-schizophrenic subjects (regardless of ALC) exhibited deficits in structural integrity and task-related recruitment of the left ventrolateral prefrontal cortex (vlPFC). Our data suggest that ALC-related impairment in the ability to infer other people's mental states is limited to insular dysfunction and thus deficits in affective empathy. By contrast, mentalizing in schizophrenia (regardless of ALC) may be associated with insular dysfunction as well as a combination of structural and functional deficits in the left vlPFC.

Particle size, surface hydrophobicity and interaction with serum of parenteral fat emulsions and model drug carriers as parameters related to RES uptake

Fat emulsions for parenteral nutrition, stabilized by egg lecithin, were characterized in terms of parameters relevant to uptake by the reticuloendothelial system (RES), e.g. size distribution, surface hydrophobicity and adsorption of serum components as a measure of the degree of opsonization. Adsorption of serum components was quantified by zeta potential measurement. Fat emulsions for nutrition were compared with emulsions used for drug delivery and model drug carries for intravenous injection. The emulsions for drug delivery were stabilized by the blockcopolymers Poloxamer 188 and 407 (Pluronic F68 and F127) and Poloxamine 908. Model drug carriers were hydrophobic and hydrophilic polystyrene latex particles. Hydrophilic particles were prepared by adsorption of Poloxamine 908 (coating) onto the particle surface. The hydrophobicity and serum protein adsorption decreased from hydrophobic latex particles to egg lecithin emulsions and blockcopolymer emulsions and particles. The data correlated with that in the literature concerning liver uptake in vivo showing complete RES clearance of hydrophobic latex particles, reduced uptake of egg lecithin emulsions and avoidance of RES uptake by Poloxamine 908 coated particles.

Disentangling structural brain alterations associated with violent behavior from those associated with substance use disorders

CONTEXT

Studies aimed at identifying structural brain alterations associated with persistent violent behavior or psychopathy have not adequately accounted for a lifetime history of substance misuse. Thus, alterations in gray matter (GM) volume that have been reported to be correlates of violent behavior and/or psychopathy may instead be related to lifelong substance use disorders (SUDs).

OBJECTIVE

To identify alterations in GM volume associated with violent behavior and those associated with lifelong SUDs.

DESIGN

Cross-sectional study.

SETTING

Participants were recruited from penitentiaries, forensic hospitals, psychiatric outpatient services, and communities in Germany. Structural magnetic resonance imaging was performed at a university hospital.

PARTICIPANTS

Four groups of men were compared: 12 men with SUDs who exhibited violent behavior (hereafter referred to as violent offenders), 12 violent offenders without SUDs, 13 men with SUDs who did not exhibit violent behavior (hereafter referred to as nonoffenders), and 14 nonoffenders without SUDs.

MAIN OUTCOME MEASURES

Voxel-based morphometry was used to analyze high-resolution magnetic resonance imaging scans. Assessments of mental disorders, psychopathy (using the Psychopathy Checklist-Screening Version), aggressive behavior, and impulsivity were conducted by trained clinicians.

RESULTS

Compared with nonoffenders, violent offenders presented with a larger GM volume in the amygdala bilaterally, the left nucleus accumbens, and the right caudate head and with less GM volume in the left insula. Men with SUDs exhibited a smaller GM volume in the orbitofrontal cortex, ventromedial prefrontal cortex, and premotor cortex than did men without SUDs. Regression analyses indicated that the alterations in GM volume that distinguished the violent offenders from nonoffenders were associated with psychopathy scores and scores for lifelong aggressive behavior. The GM volumes of the orbitofrontal cortex and prefrontal cortex that distinguished the men with SUDs from the men without SUDs were correlated with scores for response inhibition.

CONCLUSIONS

These findings suggest that a greater GM volume in the mesolimbic reward system may be associated with violent behavior and that reduced GM volumes in the prefrontal cortex, orbitofrontal cortex, and premotor area characterize men with SUDs.

Absorption of Isosorbide Dinitrate after Administration as Spray, Ointment and Microemulsion Patch. An In-vitro Study Using the Isolated Perfused Bovine Udder

The isolated perfused bovine udder is an in-vitro model, which maintains bovine udder skin with an isolated vasculature in a viable state. Using this in-vitro model, the percutaneous absorption and metabolism of isosorbide dinitrate (ISDN) was studied.

The organ was perfused with gassed Tyrode solution for up to 6 h. A region of udder skin was treated topically with 60 mg ISDN as a spray, 60 mg ISDN as an ointment and with 120mg ISDN as a microemulsion patch of 30 cm2. Spray and ointment were applied onto a skin region of 400 cm2. The concentrations of ISDN and its metabolites isosorbide-2-mononitrate and isosorbide-5-mononitrate were measured in perfusate fractions by capillary column gas-liquid chromatography with electron capture detection.

Following topical administration of the different formulations, ISDN as well as its metabolites were detected in the perfusate fractions, thus demonstrating that ISDN is metabolized by the udder skin in-vitro. A maximum amount of ISDN was absorbed after administration as a spray followed by ointment and microemulsion (5, 2·5 and 1·8 μmol total organic nitrate, respectively). In contrast, the ISDN flux per cm2 skin was significantly higher after administration of the microemulsion (64·4 pmol cm−2 min−1 for the microemulsion compared with 21·9 and 10·2 pmol cm−2 min−1 for spray and ointment).

Cognitive behavioural therapy versus supportive therapy for persistent positive symptoms in psychotic disorders: the POSITIVE Study, a multicenter, prospective, single-blind, randomised controlled clinical trial

BACKGROUND

It has been demonstrated that cognitive behavioural therapy (CBT) has a moderate effect on symptom reduction and on general well being of patients suffering from psychosis. However, questions regarding the specific efficacy of CBT, the treatment safety, the cost-effectiveness, and the moderators and mediators of treatment effects are still a major issue. The major objective of this trial is to investigate whether CBT is specifically efficacious in reducing positive symptoms when compared with non-specific supportive therapy (ST) which does not implement CBT-techniques but provides comparable therapeutic attention.

METHODS/DESIGN

The POSITIVE study is a multicenter, prospective, single-blind, parallel group, randomised clinical trial, comparing CBT and ST with respect to the efficacy in reducing positive symptoms in psychotic disorders. CBT as well as ST consist of 20 sessions altogether, 165 participants receiving CBT and 165 participants receiving ST. Major methodological aspects of the study are systematic recruitment, explicit inclusion criteria, reliability checks of assessments with control for rater shift, analysis by intention to treat, data management using remote data entry, measures of quality assurance (e.g. on-site monitoring with source data verification, regular query process), advanced statistical analysis, manualized treatment, checks of adherence and competence of therapists. Research relating the psychotherapy process with outcome, neurobiological research addressing basic questions of delusion formation using fMRI and neuropsychological assessment and treatment research investigating adaptations of CBT for adolescents is combined in this network. Problems of transfer into routine clinical care will be identified and addressed by a project focusing on cost efficiency.

DISCUSSION

This clinical trial is part of efforts to intensify psychotherapy research in the field of psychosis in Germany, to contribute to the international discussion on psychotherapy in psychotic disorders, and to help implement psychotherapy in routine care. Furthermore, the study will allow drawing conclusions about the mediators of treatment effects of CBT of psychotic disorders.

Release of gentamicin sulphate from biodegradable PLGA-implants produced by hot melt extrusion

For a long-term local treatment of osteomyelitis biodegradable poly(lactic-co-glycolic acid) (PLGA) implants loaded with gentamicin sulphate (GS) were prepared, analysed and compared to the marketed product Septopal (Biomet, Darmstadt, Germany), which consists of polymethylmethacrylate (PMMA) beads loaded with the same active ingredient. The implants were manufactured by hot melt extrusion with a twin screw extruder. In order to decrease the processing temperature and to improve the drug release behaviour, polyethylene glycol 400 (PEG 400) was added as plasticizer in different concentrations. The glass transition temperature of PLGA measured by differential scanning calorimetry declined in the same manner as the extrusion temperature with increasing PEG 400 concentration. The extrudates of all batches exhibited good encapsulation efficiency between 85% and 115% of the specified content. The behaviour of the implants during exposure to a release medium were characterised by scanning electron microscopy, gravimetric analysis and finally in vitro drug release studies. The results suggest that drug liberation is not affected by the addition of PEG 400, and depends on the drug-PLGA ratio only. Extrudates with 25% GS showed a release pattern with an initially higher drug release followed by a zero order kinetic for about four weeks and showed release profiles equivalent to Septopal.

Measurement of ERK 1/2 in CSF from patients with neuropsychiatric disorders and evidence for the presence of the activated form

The clinical diagnosis of neurodegenerative disorders can be supported by soluble biomarkers in cerebrospinal fluid (CSF), such as tau protein, phospho-tau, and amyloid-beta peptides. In particular, increased CSF levels of phospho-tau in Alzheimer's disease appear to reflect disease specific pathological processes. We report here evidence for the presence of soluble MAP-kinase ERK1/2 in a small set of human CSF samples from patients with Alzheimer's disease, frontotemporal degeneration, and mild cognitive impairment. The level of total ERK1/2 in CSF as measured by electrochemiluminescent assay was correlated with that of total tau and phospho-tau. A small fraction of ERK1/2 in a pooled CSF sample was found to be in the doubly phosphorylated (activated) state. Our findings suggest that i) MAP kinase ERK1/2 is apparently released under neurodegenerative conditions in parallel with tau and phospho-tau and ii) in the future, it might be possible to find in CSF samples evidence for disease related alterations in brain kinase signaling pathways by use of highly sensitive and activation-state specific anti-kinase antibodies.

Treatment effects of serotonergic and noradrenergic antidepressants on the intensity dependence of auditory ERP components in major depression

The intensity dependent amplitude change of auditory evoked potentials (IDAP), an assumed indicator of the level of central nervous serotonergic neurotransmission, was measured in major depressive disorder (MDD, DSM-IV: 296.2, 296.3; APA 1994) before and after treatment with either a selective serotonin reuptake inhibitor or a selective noradrenaline reuptake inhibitor antidepressant and compared with the results of a healthy control group. Auditory evoked P1, N1, P2, P1/N1 and N1/P2 peak-to-peak amplitudes were evaluated in 26 in-patients with MDD prior to and after antidepressant treatment with citalopram (24 days, n=14) or reboxetine (25 days, n=12), and in 43 healthy control subjects. Clinical symptoms of MDD were assessed by means of standardized psychiatric rating scales (CGI, HDRS, HAMA and BDI). The IDAP within the control group remained stable over 24 days (N1 amplitude slope retest ANOVA p=.79). Neither applied antidepressants nor decrease of HDRS total score during treatment had a significant effect on the IDAP in the patients' sample. The conclusion that the IDAP does not reflect the temporary depressive state in MDD is discussed.

Auditory target processing in methadone substituted opiate addicts: the effect of nicotine in controls

BACKGROUND

The P300 component of the auditory evoked potential is an indicator of attention dependent target processing. Only a few studies have assessed cognitive function in substituted opiate addicts by means of evoked potential recordings. In addition, P300 data suggest that chronic nicotine use reduces P300 amplitudes. While nicotine and opiate effects combine in addicted subjects, here we investigated the P300 component of the auditory event related potential in methadone substituted opiate addicts with and without concomitant non-opioid drug use in comparison to a group of control subjects with and without nicotine consumption.

METHODS

We assessed 47 opiate addicted out-patients under current methadone substitution and 65 control subjects matched for age and gender in an 2-stimulus auditory oddball paradigm. Patients were grouped for those with and without additional non-opioid drug use and controls were grouped for current nicotine use. P300 amplitude and latency data were analyzed at electrodes Fz, Cz and Pz.

RESULTS

Patients and controls did not differ with regard to P300 amplitudes and latencies when whole groups were compared. Subgroup analyses revealed significantly reduced P300 amplitudes in controls with nicotine use when compared to those without. P300 amplitudes of methadone substituted opiate addicts were in between the two control groups and did not differ with regard to additional non-opioid use. Controls with nicotine had lower P300 amplitudes when compared to patients with concomitant non-opioid drugs. No P300 latency effects were found.

CONCLUSION

Attention dependent target processing as indexed by the P300 component amplitudes and latencies is not reduced in methadone substituted opiate addicts when compared to controls. The effect of nicotine on P300 amplitudes in healthy subjects exceeds the effects of long term opioid addiction under methadone substitution.

The intensity dependence of auditory ERP components in unmedicated patients with major depression and healthy controls. An analysis of group differences

BACKGROUND

The intensity dependent amplitude change (IDAP) of auditory evoked Event Related Potential (ERP) components has been found to correlate with the level of central serotonergic neurotransmission and to be associated with response to certain antidepressants. However, it is currently unknown whether there is a general abnormality of the IDAP in patients with major depression. Therefore, the purpose of the present study was to compare the IDAP in unmedicated depressed patients with that of healthy control subjects.

METHODS

We report the results of a study evaluating the change of auditory evoked P1, N1, P2 as well as P1/N1 and N1/P2 peak to peak amplitudes in 34 in-patients with major depressive episode prior to antidepressant treatment, and 44 healthy control subjects. Clinical symptoms of depression were assessed by means of standardized psychiatric rating scales (CGI, HDRS, HAMA and BDI).

RESULTS

In multivariate analyses of variance we found no group differences in the intensity dependent increase neither of the P1, N1, and P2 nor of the P1/N1 and N1/P2 peak to peak amplitudes between patients and controls.

CONCLUSIONS

Our data revealed no general abnormality of the IDAP in patients with major depression in comparison to healthy control subjects. This result suggests that specific alterations of the IDAP are not to be expected in major depression in general, these may be confined to subgroups of depressed patients.

Neuropsychological assessment of adult patients with attention-deficit/hyperactivity disorder

Adults with persistent attention-deficit/hyperactivity disorder (ADHD) may show cognitive deficits as compared to healthy control subjects. The aim of this study was to compare a sample of adult outpatients with ADHD on medication to healthy controls on a comprehensive neuropsychological assessment battery. Thirty adults with ADHD under stable psychopharmacological treatment and 27 healthy controls matched for age, gender, and IQ were assessed with ten tests measuring performance with regard to attention, memory, executive function, and fine motor control. Lower performance in patients as compared to controls was found in tests of verbal and visual memory, speed of visuo-motor search, set shifting, and divided attention. Indicators of response inhibition and simple response speed were less affected. Adults with ADHD show indicators of lowered cognitive performance under medication. These are related more to memory and attention under high mental load than to response inhibition or simple attention or motor performance.

Neural activation during successful and unsuccessful verbal learning in schizophrenia

Successful and unsuccessful intention to learn words was assessed by means of event-related functional MRI. Eighteen patients with schizophrenia and 15 healthy control participants were scanned while being given two word lists to read and another seven to learn with immediate recall. Neural activation patterns were segregated according to whether words were subsequently recalled or forgotten and these conditions were contrasted with each other and reading. Compared to controls, patients with schizophrenia showed deficits with regard to neural recruitment of right hippocampus and of cerebellar structures during successful verbal learning. Furthermore, a reversal of activated structures was evident in the two groups: Controls showed activation of right frontal and left middle temporal structures during the unsuccessful intention to learn. During successful learning, there was additional activation of right superior parietal lobule. In contrast, patients showed activation of right superior parietal lobule during unsuccessful and successful intention to learn. There were additional frontal and left middle temporal lobe activations during successful learning. We conclude that increased parietal activity may reflect a mechanism which compensates for the lack of hippocampal and cerebellar contributions to verbal learning in schizophrenia.

Neural Encoding Correlates of High and Low Verbal Memory Performance

Neuroimaging studies have indicated involvement of left prefrontal cortex and temporal areas in verbal memory processes. The current study used event-related functional neuroimaging to compare encoding of subsequently recalled and not recalled words in high and low memory performers. Fifteen healthy volunteers were given lists of words to learn with immediate recall and to read as a control condition. High performers reported to have visualized the words whereas low performers used a rehearsal strategy. Compared to reading, unsuccessful encoding was associated with thalamic and left premotor area (BA 6) activity. Comparing successful with unsuccessful learning yielded widespread activity of the left prefrontal and posterior temporal gyrus as well as the left superior parietal lobe in the whole group. Low performers showed activation of the left premotor area throughout learning and additionally of the left middle temporal and parahippocampal gyrus during successful encoding. High performers showed increased activation in the extrastriate cortex throughout learning and additionally in the left parietal post- and paracentral areas as well as in the right precuneus during successful encoding. The results suggest that high verbal memory performance is the result of spatiovisual activation concomitant to imagery and low performance of hippocampal and motor activation, the latter being associated with rehearsal, with a common memory circuit subserving both groups.

A new formulation concept for drugs with poor water solubility for parenteral application

The parenteral application of active substances with poor solubility in water is often bound to the use of stabilizing excipients or surfactants with serious undesired side effects. A new concept is introduced based on a drug concentrate, comprising the active substance dissolved in parenterally acceptable organic solvents, and an aqueous dilution medium, which are mixed in a special mixing device immediately prior to application and thus generating the applicable formulation directly prior to administration. Due to the requirement of formulation stability for only a few minutes, the amount of stabilizing agents can be reduced significantly. It can be shown that model drugs dissolved in a mixture of polyoxyethylen glycol, ethanol and soya lecithin as stabilizer may be mixed to an aqueous glucose solution resulting in a parenterally acceptable and administerable dispersion which is physically stable for several minutes. First in vivo data show good tolerability and blood plasma levels which are comparable to conventional solutions.

The Intensity Dependence of Auditory Evoked ERP Components Predicts Responsiveness to Reboxetine Treatment in Major Depression

INTRODUCTION

The intensity (loudness)-dependent amplitude change (IDAP) of auditory evoked event-related potential (ERP) components has been suggested as an indicator of central serotonergic neurotransmission. In patients with major depression, associations of high IDAP with favorable SSRI treatment outcome have been reported. This is the first study to assess the predictive value of the IDAP in SNRI treatment.

METHODS

We evaluated the pre-treatment intensity-dependent change of auditory evoked P1, N1, P2, and P1/N1 and N1/P2 peak-to-peak amplitudes in 14 inpatients with major depressive episode (DSM IV) in the course of 24 days of treatment with the SNRI reboxetine (6-12 mg/d).

RESULTS

Our data revealed a highly significant correlation between lower intensity-dependent N1 amplitude slopes prior to reboxetine treatment and stronger decrease of HDRS total score at Fz ( r = 0.86, P < 0.001), Fcz ( r = 0.91, P < 0.001), and Cz ( r = 0.93, P < 0.001).

CONCLUSION

This result corroborates the hypothesis of the IDAP as a differential indicator of serotonergic versus noradrenergic antidepressant psychopharmacotherapy.

Vermal atrophy of alcoholics correlate with serum thiamine levels but not with dentate iron concentrations as estimated by MRI

Chronic alcohol consumption is frequently accompanied by cerebellar degeneration. The exact aetiology of alcoholic cerebellar degeneration is still a matter of debate. The aim of the present study was to investigate whether patients with chronic alcohol consumption exhibit a decrease in dentate nuclei intensity as measured by MRI, and if so, whether this decrease correlates with cerebellar atrophy as revealed by MR imaging or with clinical signs of cerebellar ataxia. A decrease in dentate nuclei intensity would indirectly indicate that iron accumulation, and therefore, oxidative stress may play a role in alcoholic cerebellar degeneration. MRI of 45 alcoholics and 44 age and sex-matched healthy control subjects was performed using a 3D-T1-weighted fast low angle shot (FLASH) echo sequence. Signal intensities of the dentate nuclei and cerebellar white matter were bilaterally measured. Planimetric measurements of cerebellar size were performed using a 3D-T1-weighted magnetization prepared rapid acquisition gradient echo (MPRAGE) sequence. Results demonstrated that dentate nuclei intensity was not significantly decreased in patients with chronic alcohol consumption (mean +/- SD signal intensity 65.36 +/- 13.0) if compared with control subjects (mean +/- SD signal intensity 68.95 +/- 9.4) (p = 0.15). Dentate nuclei intensity did not correlate with cerebellar size neither in control subjects nor in alcoholics. In contrast, vitamin B1 level correlated with cerebellar size in alcoholics even if the vitamin B1 concentration was within normal values (r = 0.344, p = 0.028). These results support the view that thiamine deficiency rather than direct neurotoxic effects of alcohol is the main causative factor for the development of alcoholic cerebellar degeneration.

Partial solubility parameters of poly(d,l-lactide-co-glycolide)

During production of microparticles by the polymer incompatibility method a polymer solution is demixed. Therefore, investigations into solubility are often carried out when the suitability of a polymer is examined. Solubility parameters can be used to quantify the solubility. For polylactide and polyglycolide as commonly employed copolymers for microparticles the solubility parameters have rarely been documented. This study aimed to determine solubility parameters and partial solubility parameters for different proportions of lactide to glycolide for poly(D,L-lactide-co-glycolide) (PLGA). The employed methods were compared and solubility maps established. Finally the accuracy of the results was discussed for different polymer batches which were used for production of microparticles. Although the turbidity titration method was found to be the most precise, it was not possible to sufficiently explain the differences between three polymer batches during microparticle production.

The intensity dependence of the auditory evoked N1 component as a predictor of reponse to Citalopram treatment in patients with major depression

The intensity dependence of the auditory evoked N1 ERP component (IDAP) has been suggested as an indicator of central serotonergic neurotransmission with relevance to pharmacological treatment. We report the results of a study evaluating the IDAP in 16 in-patients fulfilling DSM-IV criteria for major depressive episode in the course of treatment with the SSRI Citalopram. Our data revealed a significant correlation between the intensity slopes of the N1 amplitude prior to Citalopram treatment and treatment response: patients with higher intensity slopes of N1 amplitude showed a significantly stronger decrease of HDRS-Score after Citalopram treatment than patients within the lower intensity slope ranges. Our results indicate an association of N1 amplitude intensity dependence with response to antidepressant treatment with Citalopram.