The loudness dependency of the auditory evoked N1/P2-component as a predictor of the acute SSRI response in depression

RATIONALE

A serotonergic dysfunction is supposed to play a pathogenetic role in depression, but there is a considerable number of non-responders in the acute treatment of depression with serotonergic agents like SSRI. Thus, an indicator of central serotonergic activity could lead to a more specific pharmacological treatment of depression. In animal and human data there is a growing amount of evidence that a strong loudness dependency of late auditory evoked potentials (LDAEP) is an indicator of low serotonergic activity and vice versa.

OBJECTIVE

In 29 depressive inpatients (DSM-III-R diagnosis 296.x in 28 patients, 300.4 in one patient), the hypothesis was tested that a strong LDAEP prior to treatment can predict a better clinical outcome under SSRI treatment over 4 weeks.

RESULTS

Patients with a strong pre-treatment LDAEP had a significantly greater decrease of depressive symptoms (Hamilton Scale for Depression) after 4 weeks than patients with a flat LDAEP. Significantly more responders fell into the group with a high LDAEP. Contrary to what might be expected, a second recording in a subsample of 19 patients after 4 weeks of treatment failed to show changes in the LDAEP.

CONCLUSION

Our finding confirms the hypothesis that a strong LDAEP, indicating a low serotonergic activity, is related to a favorable response to acute SSRI treatment in depression. The LDAEP is a promising tool for the prediction of response to serotonin agonists in depression and it seems to be of clinical importance.

The neural basis of the P300 potential. Focus on the time-course of the underlying cortical generators

The locations and time-courses of the neural generators of the event-related P300 potential have been well described using intracranial recordings. However, this invasive method is not adequate for usage in healthy volunteers or psychiatric patients and not all brain regions can be covered well with this approach. With functional MRI, a non-invasive method with high spatial resolution, most of these locations could be found again. However, the time-course of these activations can only be roughly determined with this method, even if an event-related fMRI design has been chosen. Therefore, we have now tried to analyse the time-course of the activations using EEG data providing a better time resolution. We have used Low Resolution Electromagnetic Tomography (LORETA) in the analysis of P300 data (27 electrodes) of healthy volunteers (n = 50) in the time frame 230-480 ms and found mainly the same activations that have been described using intracranial recordings or fMRI, i. e. the inferior parietal lobe/temporo-parietal junction (TPJ), the supplementary motor cortex (SMA) and the anterior cingulate cortex (ACC), the superior temporal gyrus (STG), the insula and the dorsolateral prefrontal cortex. In these selected regions, an analysis of the activation time-courses has been performed.

Differential prediction of first clinical response to serotonergic and noradrenergic antidepressants using the loudness dependence of auditory evoked potentials in patients with major depressive disorder

OBJECTIVE

Predictors of treatment response to serotonergic versus nonserotonergic, e.g., noradrenergic, antidepressants are of considerable clinical relevance as they could help to reduce the occurrence of patients' receiving weeks or even months of unsuccessful treatment. Several studies show that the response to selective serotonin reuptake inhibitors can be successfully predicted by using the loudness dependence of auditory evoked potentials (LDAEP), which denotes change in the amplitudes in response to different stimulus intensities and is to date one of the best validated indicators of the central serotonergic system. The aim of the current randomized prospective study was to investigate whether or not LDAEP also allows the differential prediction of treatment response to serotonergic versus noradrenergic antidepressants.

METHOD

Electrophysiologic recordings were performed on 48 subjects between 1999 and 2001. After exclusions due to artifacts, the study sample consisted of 35 unmedicated inpatients with a DSM-IV or ICD-10 diagnosis of major depressive disorder (mean +/- SD age = 42.5 +/- 10.8 years; 13 male, 22 female; mean +/- SD score of 28.9 +/- 5.7 on the Hamilton Rating Scale for Depression [HAM-D], the primary measure for psychopathology). The patients were then treated for 4 weeks with either the selective serotonin reuptake inhibitor citalopram or the noradrenaline reuptake inhibitor reboxetine.

RESULTS

Analysis of variance (F = 5.05, df = 1,31; p = .03) revealed that responders (50% improvement in HAM-D score) to the citalopram treatment were characterized by a strong LDAEP at baseline, and responders to reboxetine were characterized by a weak LDAEP at baseline. Non-responders to citalopram or reboxetine showed the inverse LDAEP characteristics, respectively.

CONCLUSION

This study is one of the first to demonstrate differential prediction of response to different classes of antidepressants. Patients at the beginning of an antidepressant treatment who show an initially strong LDAEP have a greater probability of responding to a serotonin-agonist antidepressant, whereas patients with a weak LDAEP will probably benefit more from a nonserotonergic, e.g., noradrenergic, antidepressant. If these results were replicated in a larger sample, this simple electroencephalographic method could be more broadly used in clinical practice to support clinicians in replacing the trial and error method with a more targeted and individualized approach to antidepressant treatment.

Relationship of suicide rates to economic variables in Europe: 2000-2011

BACKGROUND

It is unclear whether there is a direct link between economic crises and changes in suicide rates.

AIMS

The Lopez-Ibor Foundation launched an initiative to study the possible impact of the economic crisis on European suicide rates.

METHOD

Data was gathered and analysed from 29 European countries and included the number of deaths by suicide in men and women, the unemployment rate, the gross domestic product (GDP) per capita, the annual economic growth rate and inflation.

RESULTS

There was a strong correlation between suicide rates and all economic indices except GPD per capita in men but only a correlation with unemployment in women. However, the increase in suicide rates occurred several months before the economic crisis emerged.

CONCLUSIONS

Overall, this study confirms a general relationship between the economic environment and suicide rates; however, it does not support there being a clear causal relationship between the current economic crisis and an increase in the suicide rate.

A Ser9Gly polymorphism in the dopamine D3 receptor gene (DRD3) and event-related P300 potentials

An important reason for the interest in P300 event-related potentials are findings in patients with psychiatric disorders like schizophrenia or alcoholism in which attenuations of the P300 amplitude are common findings. The P300 wave has been suggested to be a promising endophenotype for genetic research since attenuations of the amplitude and latency can be observed not only in patients but also in relatives. In parallel, the search for genes involved in the pathogenesis of psychiatric disorders has revealed for both, schizophrenia and alcoholism an association with a DRD3 Ser9Gly polymorphism in a number of studies. In the present study, we have investigated 124 unrelated healthy subjects of German descent and have found diminished parietal and increased frontal P300 amplitudes in Gly9 homozygotes in comparison to Ser9 carriers. This finding suggests a possible role of the DRD3 receptor gene in the interindividual variation of P300 amplitudes. Further studies should address the direct role of the DRD3 Ser9Gly polymorphism in attenuated P300 amplitudes in psychiatric disorders like schizophrenia or alcoholism.

Kinematic analysis of handwriting movements in patients with obsessive-compulsive disorder

OBJECTIVES

Basal ganglia dysfunction is supposed to play a part in the pathophysiology of obsessive-compulsive disorder (OCD). A new computer aided technique for the analysis of hand movements, allowing the detection of subtle motor performance abnormalities, was applied in this study of patients with OCD and healthy controls.

METHODS

Using a digitising graphic tablet, hand motor performance was studied in 22 unmedicated patients with OCD and compared with 22 healthy controls. All subjects drew superimposed concentric circles with both the right and the left hand, in addition to writing a given sentence, their personal signature, and letter sequences in four different sizes. Kinematic parameters were calculated to quantify hand motion.

RESULTS

Patients with OCD had significant impairments of handwriting performance, reflected by lower peak velocity (sentence t=3.6; p=0.001; signature t=2.8; p=0.01) and micrographia (sentence t=3.4; p=0.002; signature t=2.5; p=0.02), compared with controls and shortened acceleration phases per stroke (sentence t=2.4; p=0.02; signature t=4.1; p=0.000). By contrast, in repetitive drawing, patients with OCD had higher peak velocity than healthy controls (group x task interaction p<0.01). There were no significant differences in left and right hand performance between groups. Patients with early versus late age of onset differed in handwriting parameters, such as handwriting consistency. Greater severity of obsessions and compulsions correlated with increasingly poor handwriting performance in patients with OCD.

CONCLUSIONS

A subtle motor dysfunction in OCD can be detected with a digitising tablet. The findings show handwriting impairments in patients with OCD, in line with the assumption that basal ganglia dysfunction is part of OCD pathophysiology. Repetitive motor pattern performance was not impaired, but rather tended to be even better in patients with OCD than in controls. The findings also support the concept that patients with OCD with early versus late age of onset differ in pathophysiological mechanisms and basal ganglia dysfunction.

P300 and symptom improvement in schizophrenia

RATIONALE

A reduced amplitude of the auditory evoked P300 was interpreted as a trait marker of schizophrenia but reports about correlations between schizophrenic psychopathology and P300 amplitude indicate also a state character.

OBJECTIVES

To shed light upon these trait and state aspects a longitudinal study was performed to investigate the influence of symptom improvement and atypical neuroleptics on the amplitudes of the P300 and their subcomponents.

METHODS

P300 was recorded in 17 schizophrenic patients before and after 4 weeks under either clozapine or olanzapine in a double-blind controlled design. For comparison, 17 age- and sex-matched healthy subjects were investigated. Parietal and frontal P300 subcomponents were investigated separately using dipole source analysis.

RESULTS

Schizophrenic patients had smaller parietal (temporo-basal dipole) but not frontal subcomponent amplitudes (temporo-superior dipole) than controls. For the whole sample subcomponent amplitudes did not change over 4 weeks despite clinical improvement but patients with a pronounced improvement of the PANSS positive score showed a slight enhancement of both subcomponents. This was not significant when the P300 amplitude was measured at a single electrode (Pz). No significant difference between clozapine and olanzapine concerning effects on P300 amplitudes were observed.

CONCLUSIONS

The results indicate that P300 subcomponents are modulated by changes of positive but not by changes of negative symptoms or different neuroleptics. This result was obvious for P300 subcomponents but not for Pz electrode measurement, which may be due to a higher reliability of the dipole source activity. The results can be integrated into a hypothetical model containing two pathophysiological subgroups of schizophrenia.

P300 subcomponents in obsessive-compulsive disorder

Hyperactivity in the frontal cortex, leading to acceleration of attentional and cognitive processes, is discussed as pathogenetic factor in obsessive-compulsive disorder (OCD), as supported by findings of neuroimaging studies. This dysfunction in patients with OCD could be reflected by the auditory event-related P300 component, since one subcomponent of the P300, the so-called P3a, is mainly generated in frontal regions. The P300 of 21 patients with OCD free of medication and 21 age- and sex-matched healthy controls was studied, and dipole source analysis was used, allowing the separation of the subcomponents P3a and P3b with high reliability. No difference concerning the P3a between OCD and healthy subjects was found. OCD patients, however, showed a larger P3b amplitude and a shorter P3b latency (only right hemisphere) as well as a shorter reaction time to target tones as the healthy controls. Since the P3b, generated mainly in the temporo-parietal junction, is related to attentional and higher cognitive functions, whereas the P3a is more related to unspecific orienting reactions, the P3b abnormalities found in these patients could be an electrophysiological correlate of overfocussed attention and faster cognitive processes in OCD, possibly due to higher arousal and noradrenergic function. Regarding the findings with small P300 amplitudes and long latencies in most of the other psychiatric patients, it is remarkable that OCD is one of the few psychiatric diseases being characterized by larger P3b amplitudes and shorter latencies.

Symptom-specific EEG power correlations in patients with obsessive-compulsive disorder

Neurophysiological studies in patients with obsessive-compulsive disorder (OCD) consistently revealed frontal alterations of cortical activity but otherwise showed inhomogeneous results, conceivably due to variable subgroups with diverse pathomechanisms involved. The aim of this study was to investigate quantitative electroencephalography (EEG) in patients with OCD as compared to healthy controls and to correlate neurophysiological data with clinical variables. EEGs were digitally recorded from 18 unmedicated patients (8 male, mean age 32.4+/-11.8 years, Yale-Brown Obsessive-Compulsive Scale (Y-BOCS) 15.3+/-7.9) and 18 matched healthy controls, and analysed quantitatively. The mean frequency of EEG background activity and absolute power in delta, theta, alpha and beta frequency bands were calculated. Mean frequency of background activity was significantly lower in patients as compared to controls (-1.44/s, p<0.01), predominantly for the frontal electrode positions. Power spectra revealed increased delta- and decreased alpha-/beta-power in the group of patients (p<0.05, patients vs. controls). Correlation analyses showed significant positive correlations of EEG-power with the Y-BOCS sub-scores "obsessions", and negative correlations with the sub-scores "compulsions" (Spearman's correlations, r(s)=+0.48 to +0.70, and -0.47 to -0.6, respectively, p<0.05). The data provide evidence of a dysfunction of frontal cortical activity in patients with OCD. The opposite correlations of neurophysiological data and clinical features, i.e. obsessions and compulsions, are suggestive of pathophysiological differences based on the presence of the respective cardinal symptoms of OCD.

Clinical and biological findings in a case with 48-hour bipolar ultrarapid cycling before and during valproate treatment

BACKGROUND

The rare cases of patients with 48-hour ultrarapid cycling allow close investigation of mood cycles in affective disorders, because rhythmic changes in psychopathologic state and biological parameters happen very precisely.

METHOD

A 67-year-old white man who had experienced bipolar 48-hour ultrarapid cycling (DSM-IV 296.80) for several years was studied without any medication and then again studied 4 weeks later during treatment with valproate (1800 mg/day).

RESULTS

Objective and self ratings revealed pronounced manic states 1 day and depressed states the following day, which were found to be accompanied by rhythmic fluctuations in behavior and electroencephalographic parameters, blood cortisol and growth hormone levels (both elevated on depressive days), and urinary metanephrine (dopamine metabolite) and norepinephrine levels (both elevated on manic days). Using single photon emission computed tomography, regional blood flow in the left thalamus was lower than in the right thalamus on the manic day, while symmetric perfusion of the thalamus was found on the depressive day. Under valproate treatment, the patient remitted completely, and significant rhythmic changes in most of the biological parameters were no longer detectable.

CONCLUSION

The biological findings in this patient with bipolar 48-hour ultrarapid cycling, which correspond to those in other types of affective disorders, suggest that disturbances in the diencephalon-pituitary axis may be especially correlated to pathologic changes of mood.

Electrophysiological evidence for cortical abnormalities in obsessive-compulsive disorder - a replication study using auditory event-related P300 subcomponents

Neuroimaging studies in recent years suggest that cortical hyperactivity associated with more aroused cognitive processes and overfocussed attention is involved in the pathogenesis of obsessive-compulsive disorder (OCD), which was electrophysiologically supported by an own pilot-study in a small sample of stabilized OCD patients. To replicate this first finding, the hypothesis of cortical hyperactivity was studied by measuring auditory event-related P300 subcomponents, especially the amplitude of the P3a and P3b subcomponent, in a large sample of acutely ill and unmedicated patients with OCD. The P300 of 63 patients with OCD (30 males, 33 females, 33.7+/-10.2 years old; 25.4+/-5.4 points at Yale-Brown-Obsessive-Compulsive-Scale (Y-BOCS)) was separated with dipole source analysis (BESA) into their subcomponents P3a and P3b, and compared to the P300 subcomponents of 63 gender and age matched healthy controls. No difference in the amplitude of P3a was found, but OCD patients had significantly larger amplitudes of P3b than the healthy controls, which replicates the results of the pilot study. Once again, our findings point to a hyperactivated cortical state also of temporo-parietal and hippocampal regions in OCD.

Lithium-induced EEG changes in patients with affective disorders

In 12 patients with affective disorders (ICD-10: F31, F32, F33), EEGs were recorded before and after 4.4 months of lithium treatment. Effects of lithium on the EEG were analyzed by power spectral analysis controlled for vigilance. We found (1) an increase in relative power in both delta and theta band which was related to the lithium plasma level, (2) a decrease in relative alpha power especially at occipital leads and (3) a reduction of the dominant alpha frequency. The changes in relative power were more pronounced in the right hemisphere, which is in contrast to the hypothesis of a site-specific localization of lithium effects only in left anterior regions.

P300 in obsessive-compulsive disorder: source localization and the effects of treatment

Converging evidence suggests that frontostriatal abnormalities underlie OCD symptoms. The event-related potential P300 is generated along a widely distributed network involving several of the areas implicated in OCD. P300 abnormalities reported in patients with OCD suggest increased activity in these areas. The aim of the present study was to investigate this assumption in unmedicated patients with OCD, and to assess the effects of OCD treatment on P300 brain activity patterns. Seventy-one unmedicated patients with a DSM-IV diagnosis of OCD and 71 age- and gender-matched healthy control subjects participated in the study. The P300 was obtained through 32-channel EEG during an auditory oddball paradigm. Forty-three patients underwent a second EEG assessment after treatment with sertraline and behavioural therapy. Low-resolution electromagnetic tomography (LORETA) was used to localize the sources of brain electrical activity.

RESULTS

Increased P300-related activity was observed predominantly in the left orbitofrontal cortex, but also in left prefrontal, parietal and temporal areas, in patients compared to controls at baseline. After treatment, reduction of left middle frontal cortex hyperactivity was observed in patients.

CONCLUSIONS

Findings of increased activity in frontoparietal areas in patients are consistent with several previous studies. Importantly, OCD treatment led to reduction of hyperactivity in the left middle frontal cortex, an area associated with context processing and uncertainty that might be important for the emergence of OCD symptoms. Thus, the present study is the first to show an association between P300 abnormalities and activity in brain regions postulated to be involved in the pathophysiology of OCD.

Kinematical analysis of emotionally induced facial expressions: a novel tool to investigate hypomimia in patients suffering from depression

OBJECTIVE

A novel technique for the kinematic analysis of emotionally induced facial expressions was applied to detect subtle mimic dysfunction in patients with depression.

METHODS

Using ultrasound markers at certain points on the face, facial movements were exactly measured while subjects watched a witty sketch ("Mr Bean"). Twenty five medicated patients with depression (11 men, 14 women; mean age, 55.8 years; mean total Hamilton Depression Rating Scale score, 17.1) and 25 healthy controls, matched by sex distribution and handedness, were studied.

RESULTS

Depressed patients were characterised by abnormally slow velocity at the beginning of laughing and voluntary facial movements, in addition to reduced laughing frequency. A higher severity of symptoms of depression was significantly associated with slow initial velocity of laughing movements of the left mouth angle (r = -0.45).

CONCLUSION

The execution of voluntary and non-voluntary facial movements is abnormally slow in depressed patients, reflecting hypomimia. This mimic slowing is closely associated with the severity of depression. The response of depressed patients to emotional stimuli is also abnormally low, but emotional estimation of the stimuli is similar to normals. This pattern parallels the motor-emotional features known from patients with Parkinson's disease.

Loudness Dependence of Primary Auditory-Cortex-Evoked Activity as Predictor of Therapeutic Outcome to Prophylactic Lithium Treatment in Affective Disorders - A Retrospective Study

INTRODUCTION

Lithium has been found to be very effective in prophylactic treatment of affective disorders. However, approximately one-third of patients do not respond to this treatment, which does not become apparent until after a year or more of treatment. Therefore, predictors are needed to avoid a long and unsuccessful therapy with risk of severe side effects. Since lithium acts as a serotonin agonist in prophylactic treatment, a predictor of being able to identify patients with low serotonergic activity, who may be responders to lithium, is promising. To determine whether the loudness dependence (LDAEP) of primary, but not of secondary, auditory-cortex-evoked activity, which is inversely related to central serotonergic neurotransmission, could be such a predictor, responders and non-responders to prophylactic lithium treatment were compared.

METHODS

Thirty patients with uni- and bipolar affective disorders, who have taken a prophylactic lithium medication continuously for at least 3 years, were included in the study. Patients were classified as responders if they had no hospitalization within the past 3 years. Dipole source analysis allowing us to separate evoked activity of the primary and secondary auditory cortex was used.

RESULTS

The LDAEP of the primary, but not of the secondary, auditory cortex was significantly stronger in the responders to the lithium treatment than in the non-responders, implicating low serotonergic function in these patients.

DISCUSSION

This finding, which is in line with previous studies, suggests that loudness dependence of primary auditory-cortex-evoked activity could be a clinically relevant predictor of prophylactic treatment with lithium in affective disorders.

Assessment of handedness using a digitizing tablet: a new method

The assessment of handedness is of interest in some psychiatric populations, above all in schizophrenic patients, because there may be a relationship between neurodevelopmental, hemispheric damage and psychiatric disease processes (Crow TJ. Schizophrenia Bulletin 1990;16:433-443; Tyler M, Diamond J, Lewis S. Schizophrenia Research 1995;18:37-41). Various methods to assess handedness have been proposed. In order to detect the most precise instrument for the assessment of handedness, two different measures, a questionnaire and a computational procedure for movement analysis, were compared in a group of healthy subjects. The ability of the methods to discriminate not only between the groups of right-handers (n=12) and left-handers (n=23), but also between left-handers trained in school to use the non-dominant right hand ('inconsistent' left-handers; n=11) and those allowed to use their left hand for writing ('consistent' left-handers; n=12) was investigated. For future investigations, our main concern was to determine if one method had superiority over the other. The results revealed that the Edinburgh Handedness Inventory (EHI) distinguishes just as well as the computational method between right-handers and non-right-handers. However, more precise discrimination between the subgroups of 'consistent' and 'inconsistent' left-handers is possible using digitized analysis of hand-motor performance. According to our results handedness should be assessed not only with the EHI, but also with the computer-aided analysis of hand-movements.

Association of 5-HT1B receptor polymorphisms with the loudness dependence of auditory evoked potentials in a community-based sample of healthy volunteers

The terminal autoreceptor 5-HT1B is centrally involved in the regulation of the brain serotonergic system and in several psychiatric disorders including depression, addiction, and obsessive-compulsive disorder. The loudness dependence of the auditory evoked N1/P2-component (LDAEP; primary auditory cortex) is currently considered as one of best-validated indicators of serotonergic neurotransmission, especially for synaptically released serotonin. Since the 5-HT1B receptor is involved in the release of serotonin at terminal endings of cortical neurons, this study addressed the question whether single nucleotide polymorphism (SNP) in the gene coding for this receptor (HTR1B) are related to LDAEP of the primary auditory cortex (tangential dipole) investigating a community-based sample of 127 healthy subjects randomly selected from the general population. In this carefully recruited sample, a G-G haplotype (rs1213368-rs6296) and the respective G-alleles were found to be related to a strong LDAEP response of the left tangential dipole, indicating low serotonergic activity. Apart from the fact that this is the first study which relates HTR1B SNPs to a measure of serotonergic function, it can be speculated that LDAEP may reflect parts of the release mechanism of serotonin at cortical synapses, although the lateralized finding cannot be entirely explained. Carriers of the G-alleles may be characterized by a particularly strong feedback inhibition of serotonin release at cortical terminals in the primary auditory cortex, possibly mediated by higher sensitivity of 5-HT1B receptors associated with low serotonergic activity.

Prefrontal cortex modulation of mood and emotionally induced facial expressions: a transcranial magnetic stimulation study

Repetitive transcranial magnetic stimulation (rTMS) can serve as a tool to experimentally test hypotheses of prefrontal cortex (PFC) modulation of emotions. The present study used rTMS to test whether self-rated mood and emotionally induced facial expressions are hemispherically lateralized depending on their valence, as indicated by previous studies. Healthy volunteers underwent mood self-rating and computerized analysis of emotionally induced facial expressions before and after rTMS of left or right PFC. Facial expression analysis revealed lateralized changes of facial expressions after rTMS, whereas changes of subjective mood ratings did not show a hemispheric lateralization. On the basis of this study, the authors propose to combine rTMS and facial expression analysis for further studies of the cortical modulation of emotions in humans.

Serotonergic functioning as measured by the loudness dependence of auditory evoked potentials is related to a haplotype in the brain-derived neurotrophic factor (BDNF) gene

OBJECTIVES

The serotonergic system plays an important pathophysiological role in various psychiatric disorders. Brain-derived neurotrophic factor (BDNF) is involved in the differentiation and survival of serotonergic neurons. A previous study showed that low serum BDNF levels were associated with strong loudness dependence of auditory evoked potentials (LDAEP) as a reflection of low central serotonergic activity. To evaluate the genetic basis of this relationship, we studied whether the LDAEP is correlated with genetic variants within the BDNF gene.

METHODS

Ninety five healthy subjects (41 males, 54 females) received electrophysiological recording of LDAEP and blood drawing for BDNF genotyping. Three BDNF markers (including the single nucleotide polymorphism rs6265(Val66Met)) were analyzed.

RESULTS

Haplotype analysis revealed stronger LDAEP values in carriers of the G(Val)-C-T [rs6265(Val66Met)-rs2030324-rs1491850] haplotype within the BDNF gene in comparison to other haplotype carriers. These findings were demonstrated for the LDAEP of both left and right primary auditory cortices as well as for the vertex electrode (Cz).

CONCLUSION

Subjects with the BDNF haplotype G(Val)-C-T seem to be characterized by low serotonergic activity as well as possibly by low serum BDNF levels. These findings need replication in independent samples.

Association of catechol-O-methyltransferase variants with loudness dependence of auditory evoked potentials

OBJECTIVE

The loudness dependence of auditory evoked potentials (LDAEP) provides a measure of the central serotonergic activity. As dopamine transporter availabilities also correlate with LDAEP, a dopaminergic influence is probable. The enzyme catechol-O-methyltransferase (COMT) is involved in the inactivation of synaptic dopamine. The aim of this study was to investigate the relationship between genetic variants of the COMT gene influencing synaptic dopamine levels and the LDAEP.

METHODS

Rs737865 in intron 1, rs4680 coding for a Val158Met substitution and rs165599 in the 3' region were investigated in 95 carefully selected healthy subjects of German descent (41 males, 54 females). The LDAEP was calculated as a linear regression slope with stimulus intensity as independent and N1/P2-amplitude as dependent variables.

RESULTS

Single marker analysis showed weak associations for two single nucleotide polymorphisms (SNPs) (rs737865: CC vs. T allele carrier; rs4680: G-allele carrier vs. AA homozygotes). A-G (rs4680-rs165599) was associated with lower LDAEP scores. Accordingly, haplotype analysis with all SNPs (rs737865-rs4680-rs165599) showed that the T-A-G haplotype was associated with lower scores.

CONCLUSIONS

These findings support the hypothesis that the LDAEP is also influenced by dopaminergic transmission. However, replications of these very preliminary but potentially important findings in independent samples are needed.

The management of psychiatric emergencies

BACKGROUND

Psychiatric emergencies such as acute psychomotor agitation or suicidality often arise in non-psychiatric settings such as general hospitals, emergency services, or doctors' offices and give rise to stress for all persons involved. They may be life-threatening and must therefore be treated at once. In this article, we discuss the main presenting features, differential diagnoses, and treatment options for the main types of psychiatric emergency, as an aid to their rapid and effective management.

METHOD

Selective literature review.

RESULTS AND CONCLUSION

The frequency of psychiatric emergencies in non-psychiatric settings, such as general hospitals and doctors' offices, and their treatment are poorly documented by the few controlled studies and sparse reliable data that are now available. The existing evidence suggests that the diagnosis and treatment of psychiatric emergencies need improvement. The treatment of such cases places high demands on the physician's personality and conduct, aside from requiring relevant medical expertise. Essential components of successful treatment include the establishment of a stable, trusting relationship with the patient and the ability to "talk down" agitated patients calmly and patiently. A rapid and unambiguous decision about treatment, including consideration of the available options for effective pharmacotherapy, usually swiftly improves the acute manifestations.

Effects of sertraline on kinematic aspects of hand movements in patients with obsessive-compulsive disorder

RATIONALE

Movement disorders such as disturbances of fine motor co-ordination are a frequent phenomenon in patients with obsessive-compulsive disorder (OCD).

OBJECTIVES

Our aim was to investigate changes of hand-motor dysfunction in OCD patients under the influence of 10-week treatment with sertraline and behaviour therapy.

METHODS

We examined the performance of 40 patients satisfying DSM-IV criteria for OCD before and under this therapy using a digitising tablet and kinematic analysis of handwriting and drawing movements. Forty healthy controls were also tested (test-retest interval: 10 weeks).

RESULTS

The speed of drawing was significantly lower in OCD patients than in controls (mean+/-standard deviation=197.03+/-113.26 mm/s for patients and 182.48+/-189.61 mm/s for controls; P=0.01). After 10 weeks of therapy, this parameter normalised in patients (from 197.03+/-113.26 mm/s to 163.66+/-101.92 mm/s; P=0.001).

CONCLUSIONS

Hand-motor dysfunction (especially bradykinesia) improves with a serotonin-enhancing therapy in OCD patients.

Death anxiety and attitude to death in patients with schizophrenia and depression

Attitude to death and death anxiety in patients with severe psychiatric disorders have been studied rarely so far, although this is an existential perspective for each human being and clinically seems to be changed in patients with depression and schizophrenia. Patients with depression (mean age 46.30 ± 13.39; 12 women, 8 men) and schizophrenia (mean age 38.95 ± 1285; 9 women, 11 men), as well as healthy controls, were included in the study. Death anxiety and attitude to death were assessed using the newly developed and currently validated BOFRETTA scale. Attitude to death was significantly worse in the group of patients with schizophrenia, especially in those with prominent negative symptoms. Concerning death anxiety, patients with schizophrenia and also those with depression exhibited higher mean values compared with healthy controls in the same age range. These results suggest that there are specific similarities and differences concerning attitude to death and death anxiety in patients with psychotic and affective disorders. It can be concluded that existential aspects such as death and meaningful life should also be considered within the treatment of patients with severe mental disorders.

Serotonergic modulation of orbitofrontal activity and its relevance for decision making and impulsivity

BACKGROUND

The orbitofrontal cortex seems to play a crucial role in reward-guided learning and decision making, especially for impulsive choice procedures including delayed reward discounting. The central serotonergic system is closely involved in the regulation of impulsivity, but how the serotonergic firing rate and release, best investigated by the loudness dependence of auditory evoked potentials (LDAEP), interact with orbitofrontal activity is still unknown.

METHODS

Twenty healthy volunteers (11 males, 9 females, 31.3 ± 10.6 years old) were studied in a 3T MRI scanner (Philips, Hamburg, Germany) during a delay discounting task, after their LDAEP was recorded using a 32 electrodes EEG machine (Brain Products, Munich, Germany).

RESULTS

Significant positive correlations were only found between the LDAEP and the medial orbitofrontal part of the superior frontal gyrus (SFG/MO) [Δ immediate reward - delayed reward] for the right (r = 0.519; P = 0.019) and left side (r = 0.478; P = 0.033). This relationship was stronger for females compared with males. Orbitofrontal activity was also related to the Barratt Impulsivity Scale.

CONCLUSIONS

This study revealed that low serotonergic activity as measured by a strong LDAEP was related to a high fMRI signal intensity of SFG/MO during immediate reward behavior which is related to impulsivity. Since this relationship was only found for the infralimbic medial and not for the middle or lateral part of the orbitofrontal cortex, an exclusive projection tract of the serotonergic system to this cortical region can be assumed to regulate impulsive reward-orientated decision making. Hum Brain Mapp 38:1507-1517, 2017. © 2016 Wiley Periodicals, Inc.

Kinematical analysis of emotionally induced facial expressions in patients with obsessive-compulsive disorder

BACKGROUND; Motor function is deficient in many patients with obsessive-compulsive disorder (OCD), especially in the face. To investigate subtle motor dysfunction, kinematical analysis of emotional facial expressions can be used. Our aim was to investigate facial movements in response to humorous film stimuli in OCD patients.

METHOD

Kinematical analysis of facial movements was performed. Ultrasound markers at defined points of the face provided exact measurement of facial movements, while subjects watched a humorous movie ('Mr Bean'). Thirty-four OCD patients (19 male, 15 female; mean (S.D.) age: 35.8 (11.5) years; mean (S.D.) total Y-BOCS score: 25.5 (5.9)) were studied in unmedicated state and after a 10-week treatment with the SSRI sertraline. Thirty-four healthy controls (19 male, 15 female; mean (S.D.) age: 37.5 (13.1) years) were also investigated.

RESULTS

At baseline, OCD patients showed significantly slower velocity at the beginning of laughing than healthy controls and a reduced laughing frequency. There was a significant negative correlation between laughing frequency and severity of OCD symptoms. Ten weeks later a significant increase of laughing frequency and initial velocity during laughing was found.

CONCLUSIONS

Execution of adequate facial reactions to humour is abnormally slow in OCD patients. Susceptibility of OCD patients with regard to emotional stimuli is less pronounced than in healthy subjects. This phenomenon is closely correlated to OCD symptoms and is state-dependent.