A subgroup of light-driven sodium pumps with an additional Schiff base counterion

Light-driven sodium pumps (NaRs) are unique ion-transporting microbial rhodopsins. The major group of NaRs is characterized by an NDQ motif and has two aspartic acid residues in the central region essential for sodium transport. Here we identify a subgroup of the NDQ rhodopsins bearing an additional glutamic acid residue in the close vicinity to the retinal Schiff base. We thoroughly characterize a member of this subgroup, namely the protein ErNaR from Erythrobacter sp. HL-111 and show that the additional glutamic acid results in almost complete loss of pH sensitivity for sodium-pumping activity, which is in contrast to previously studied NaRs. ErNaR is capable of transporting sodium efficiently even at acidic pH levels. X-ray crystallography and single particle cryo-electron microscopy reveal that the additional glutamic acid residue mediates the connection between the other two Schiff base counterions and strongly interacts with the aspartic acid of the characteristic NDQ motif. Hence, it reduces its pKa. Our findings shed light on a subgroup of NaRs and might serve as a basis for their rational optimization for optogenetics.

The optimized combination of aCompCor and ICA-AROMA to reduce motion and physiologic noise in task fMRI data

One of the main challenges in fMRI processing is filtering the task BOLD signals from the noise. Independent component analysis with automatic removal of motion artifacts (ICA-AROMA) reduces motion artifacts by identifying ICA noise components based on their location at the brain edges and cerebrospinal fluid (CSF), high frequency content and correlation with motion regressors. In anatomical component correction (aCompCor), physiological noise regressors extracted from CSF were regressed out from the fMRI time series. In this study, we compared three methods to combine aCompCor and ICA-AROMA denoising in one denoising step. In the first analysis, we regressed the temporal signals of the ICA components identified as noise by ICA-AROMA together with the noise signals determined by aCompCor from the fMRI signals. For the second and third analyses, the correlation between the temporal signals of the ICA components and the aCompCor noise signals was used as an additional criterion to identify the noise components. In the second analysis, the temporal signals of the ICA components classified as noise were regressed from the fMRI signals. In the third analysis, the noise components were removed. To compare the denoising strategies, we examined the fractional amplitude of low-frequency fluctuations (fALFF) and the overlap between the contrast maps. Our results revealed that including the aCompCor noise signals as regressors in ICA-AROMA resulted in more correctly identified noise components, higher fALFF values, and larger activation maps. Moreover, combining the temporal signals of the noise components identified by ICA-AROMA with the aCompCor signals in a noise regression matrix resulted in deactivations. These results suggest that using the correlation between the ICA component temporal signals and the aCompCor signals as noise identification criteria in ICA-AROMA is the best approach for combining both denoising methods.

Suicidality during neuromodulation in the elderly depressed: study design

Introduction

Late life depression is a major global health issue, with an estimated 7% of older adults suffering from this mental disorder. Depression is one of the most important predictors for suicide in the elderly. However, it is often difficult to recognize and manage, making treatment-resistance a common occurrence. Treatment-resistant depression itself is also a known risk factor for suicide. Recently, non-invasive neuromodulation techniques have been used as a new treatment for depression and suicidality with promising results.

Objectives

This study aims to investigate the effect of adTMS (accelerated deep Transcranial Magnetic Stimulation) and tDCS (transcranial Direct Current Stimulation) on the suicidality of elderly, therapy-resistant depressed patients. The hypothesis is that suicidal ideation and risk of suicide will decrease after a treatment with adTMS and tDCS.

Methods

In this randomized double-blinded sham-controlled clinical trial, geriatric therapy-resistant depressive patients will receive adTMS treatment (See: Figure 1). Suicidality will be assessed before and after the active or sham treatment, through the Columbia Suicide Severity Rating Scale (C-SSRS) and Beck Scale for Suicide Ideation (BSI). After one week of rest, all patients will receive an at-home tDCS treatment for 3 weeks. Likewise, the suicide risk will be estimated before and after the tDCS. During the screening period, the severity of the patients’ depressive symptoms will be determined by using the 17-item Hamilton Depression Rating Scale (HDRS-17). In total, the trial will last for 5 weeks, and suicidality will be examined at five different time points (during screening, at T0, T1, T2 and T3).

Results

Not applicable

Conclusions

Not applicable

Disclosure

No significant relationships.

[Transcranial direct current stimulation in substance use disorders: an update]

BACKGROUND

Existing treatments for substance use disorders are often subject to drop-out or relapse. Transcranial direct current stimulation (tDCS) possibly has a positive effect on this problem.

AIM

To give an updated qualitative review of existing studies investigating the clinical effects of transcranial direct current stimulation for people with a substance use disorder, considering the many recently published studies.

METHOD

Extensive literature search in the electronic database PubMed. We included 43 studies on top of the 7 studies already included in the previous review of Herremans and Baeken (2017) in this journal.

RESULTS

The majority of the studies showed a positive effect of transcranial direct current stimulation on clinical measures as craving and abstinence. However, there was little uniformity in used protocols.

CONCLUSION

Transcranial direct current stimulation can be an effective treatment for people with a substance use disorder. Optimal parameters need to be established to make the treatment maximally effective and adapted to the individual patient.

Na+-dependent gate dynamics and electrostatic attraction ensure substrate coupling in glutamate transporters

Excitatory amino acid transporters (EAATs) harness [Na⁺], [K⁺], and [H⁺] gradients for fast and efficient glutamate removal from the synaptic cleft. Since each glutamate is cotransported with three Na⁺ ions, [Na⁺] gradients are the predominant driving force for glutamate uptake. We combined all-atom molecular dynamics simulations, fluorescence spectroscopy, and x-ray crystallography to study Na⁺:substrate coupling in the EAAT homolog Glt_Ph A lipidic cubic phase x-ray crystal structure of wild-type, Na⁺-only bound Glt_Ph at 2.5-Å resolution revealed the fully open, outward-facing state primed for subsequent substrate binding. Simulations and kinetic experiments established that only the binding of two Na⁺ ions to the Na1 and Na3 sites ensures complete HP2 gate opening via a conformational selection-like mechanism and enables high-affinity substrate binding via electrostatic attraction. The combination of Na⁺-stabilized gate opening and electrostatic coupling of aspartate to Na⁺ binding provides a constant Na⁺:substrate transport stoichiometry over a broad range of neurotransmitter concentrations.

Compulsory admissions of patients with mental disorders: State of the art on ethical and legislative aspects in 40 European countries

Background.

Compulsory admission procedures of patients with mental disorders vary between countries in Europe. The Ethics Committee of the European Psychiatric Association (EPA) launched a survey on involuntary admission procedures of patients with mental disorders in 40 countries to gather information from all National Psychiatric Associations that are members of the EPA to develop recommendations for improving involuntary admission processes and promote voluntary care.

Methods.

The survey focused on legislation of involuntary admissions and key actors involved in the admission procedure as well as most common reasons for involuntary admissions.

Results.

We analyzed the survey categorical data in themes, which highlight that both medical and legal actors are involved in involuntary admission procedures.

Conclusions.

We conclude that legal reasons for compulsory admission should be reworded in order to remove stigmatization of the patient, that raising awareness about involuntary admission procedures and patient rights with both patients and family advocacy groups is paramount, that communication about procedures should be widely available in lay-language for the general population, and that training sessions and guidance should be available for legal and medical practitioners. Finally, people working in the field need to be constantly aware about the ethical challenges surrounding compulsory admissions.

[Consensus statement on the application of rTMS in depression in the Netherlands and Belgium]

Since 2017, repetitive transcranial magnetic stimulation (rTMS) has become eligible for reimbursement for the treatment of therapy-resistant depression in the Dutch healthcare system.<br/> AIM: To initiate a guideline in the Netherlands and Belgium for the safe and effective application of rTMS for the treatment of depression.<br/> METHOD: Based on literature review, existing guidelines and consensus among Dutch rTMS experts, recommendations were developed regarding the implementation of rTMS as a treatment of depression. All available evidence was weighed and discussed among all co-authors and recommendations were reached by consensus among the group.<br/> RESULTS: rTMS targeting the dorsolateral prefrontal cortex (DLPFC) should be seen as a first choice in the treatment of depression using high-frequency rTMS (left) or, as an alternative, low-frequency rTMS (right). Stimulation protocols should use more than 1000 pulses per session for an average of 20-30 sessions, offered in 2-5 sessions per week. Contraindications for rTMS include epilepsy, intracranial presence of (magnetisable) metals, pacemaker and cochlear implant.<br/> CONCLUSION: rTMS, performed by competent professionals is an effective and safe treatment for depression.

Changes in canine cerebral perfusion after accelerated high frequency repetitive transcranial magnetic stimulation (HF-rTMS): A proof of concept study

Repetitive transcranial magnetic stimulation (rTMS) has been proposed as a treatment for several neuropsychiatric disorders in human beings, but the neurobiological effects of rTMS in dogs have not been investigated to date. A proof of concept study was designed to evaluate the effect of rTMS on cerebral perfusion, measured with single photon emission computed tomography (SPECT), in dogs. An accelerated high frequency (aHF)-rTMS (20Hz) protocol was applied to the canine left frontal cortex. To accurately target this area, eight dogs underwent a 3 Tesla magnetic resonance imaging (MRI) scan before stimulation. The left frontal cortex was subjected to five consecutive aHF-rTMS sessions with a figure-of-eight coil designed for human beings at an intensity of 110% of the motor threshold. The dogs underwent ^99mTc-d,1 hexamethylpropylene amine oxime (HMPAO) SPECT scans 1 week prior to and 1day after the stimulations. Perfusion indices (PIs) were determined semi-quantitatively; aHF-rTMS resulted in significantly increased PIs in the left frontal cortex and the subcortical region, whereas no significant differences were noted for the other regions. Behaviour was not influenced by the stimulation sessions. As has been observed in human beings, aHF-rTMS applied to the left frontal cortex alters regional cerebral perfusion in dogs.

[Clinical effects of non-invasive neuromodulation techniques in substance use disorder: an overview]

BACKGROUND

Substance dependence is a chronic disorder that is difficult to treat. Non-invasive stimulation techniques may have beneficial effects on the course of the illness.

AIM

To provide an overview of studies that evaluate the clinical effects that transcranial magnetic stimulation (tMS) and transcranial direct current stimulation (tDCS) have on patients with substance use disorders.

METHOD

We performed an extensive search of the literature, using PubMed.

RESULTS

Most studies showed that both tMS and tDCS have a beneficial effect on clinical outcomes. However, the effects seemed to wear off over time, even if tMS and tDCS had been administered to patients over several sessions.

CONCLUSION

In terms of efficacy, we award a level B qualification to both tMS and tDCS, which means that we regard both techniques as 'very probably efficient'.

[Non-invasive neurostimulation in the treatment of child and adolescent psychiatry]

Neurostimulation is a potentially interesting treatment option for children and adolescents with psychiatric disorders.<br/> AIM: To review the efficacy of two non-invasive neurostimulation techniques, namely repetitive transcranial magnetic stimulation (rtms) and transcranial direct current stimulation (tdcs), in the treatment of child and adolescent psychiatric disorders.<br/> METHOD: We searched the literature research using PubMed.<br/> RESULTS: There is some evidence that rtms is being used to treat unipolar depression, psychosis, autism spectrum disorder, attention deficit hyperactivity disorder and tic disorder. So far, however, very little research has been done on tdcs.<br/> CONCLUSION: Further research is vitally important in order to ensure the safety and efficacy of rtms and tdcs.

[Brain stimulation: the most direct form of neurostimulation]

BACKGROUND

Brain stimulation is the most direct form of neuromodulation. Direct brain stimulation is an older procedure that has taken various forms, but 'non-invasive brain stimulation' is a more recent development.

AIM

To provide an overview of the current arsenal of non-invasive brain stimulation techniques.

METHOD

We discuss the underlying principles, the pros and cons, and the applicability of non-invasive brain stimulation in experimental research and treatment of neuropsychiatric disorders.

RESULTS

Non-invasive brain stimulation is a direct form of neuromodulation, which is not invasive, harmful or painful. Its effects are in principle temporary, which makes the technique suitable for experimental research. At the same time, temporary effects can have lasting clinical consequences, if they target neuroplasticity to aid rehabilitation or alleviate symptoms.

CONCLUSION

Whereas the value of non-invasive brain stimulation for research purposes is undisputed, its efficacy and value as a treatment for neuropsychiatric disorders are still being debated. Nevertheless, the accumulated evidence about the clinical efficacy of the treatment for certain disorders is sufficiently compelling to start thinking about European regulations and standard medical insurance coverage.

[Non-invasive brain stimulation techniques in psychiatric disorders: influential factors and combination of interventions]

BACKGROUND

The causal influence of cortico-subcortical connectivity by means of brain stimulation seems to be an effective biological treatment in psychiatric patients.

AIM

To review the working mechanisms and moderating factors of two non-invasive brain stimulation techniques (NIBS), namely repetitive transcranial magnetic stimulation (rTMS) and transcranial direct current stimulation (tDCS).

METHOD

We reviewed the current literature on the use of nibs in neuropsychiatric disorders.

RESULTS

First of all, stimulation parameters (location of the stimulation, intensity and duration of the stimulation, number of sessions) are important for the effect of nibs. Secondly, it is important to consider the non-specific neuroplasticity that results from NIBS. Thirdly, recent studies suggest that NIBS should be combined with neurobehavioral interventions, namely cognitive interventions, for the purpose of modulating specific neural processes (i.e. specific neuroplasticity).

CONCLUSION

If we want to improve the NIBS treatment in neuropsychiatric patients, we need to consider the factors that influence the patients' response to treatment with rTMS and tDCS.

Dual Target Repetitive Transcranial Magnetic Stimulation In The Treatment Of Comorbid Obsessive-Compulsive Disorder In Patients With Anorexia Nervosa: Preliminary Results Of Two Case Reports

Introduction

Obsessive-compulsive disorder (OCD) is a frequently reported comorbid disorder (20–30%) in patients with anorexia nervosa (AN). Increasing evidence suggests that repetitive transcranial magnetic stimulation (r-TMS) may be effective in the treatment of refractory OCD and to a lesser extent in AN. Hereby, different target areas: supplemental motor area (SMA) and orbitofrontal cortex (OFC) and dorsolateral prefrontal cortex in AN. We report two patients with enduring AN and comorbid treatment resistant OCD treated with r-TMS.

Methods

Both female patients (34 and 26 years respectively) were hospitalized at the Eating Disorder Unit at the Ghent University Hospital. Treatment responses were evaluated with Yale Brown Obsessive Compulsive Scale (Y-BOCS) and weight gain. Inhibitory continuous thetaburst stimulation (cTBS) of the SMA followed by cTBS of the OFC was conducted during 20 sessions, 5 sessions a week, during 4 weeks. Stimulation intensity was respectively 100% and 80% of the motor treshold.

Results

After cTBS treatment Y-BOCS score of both patients decreased (31 to 24 and 31 to 23 respectively). Only one patient showed a 10% increase of weight. The treatment was well tolerated. No significant side effects were reported.

Conclusion

Treatment resistant comorbid OCD in patients with AN may be succesfully treated with cTBS.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

Reduced intra-individual reaction time variability during a Go-NoGo task in detoxified alcohol-dependent patients after one right-sided dorsolateral prefrontal HF-rTMS session

AIMS

As alcohol dependency is characterized by severe executive function deficits, we examined the influence of high-frequency (HF) repetitive transcranial magnetic stimulation (rTMS) applied to the right dorsolateral prefrontal cortex (DLPFC) on executive functioning in recently detoxified alcohol-dependent patients.

METHODS

In this randomized, single blind, sham (placebo)-controlled, crossover study, we included 50 detoxified alcohol-dependent patients. We examined the effect of a single right DLPFC HF-rTMS session on commission errors, mean reaction times (RTs) and intra-individual reaction time variability (IIRTV) during a Go-NoGo task (50% Go/50% NoGo condition) in 29 alcohol-dependent patients. Patients completed this cognitive task immediately before and immediately after the stimulation session. In order to avoid carry-over effects between stimulation sessions, a 1-week inter-session interval was respected. Because rTMS treatment has been shown to affect subjective craving, all patients were also assessed with the Obsessive Compulsive Drinking Scale (OCDS).

RESULTS

After both stimulation conditions, we observed a significant decrease of commission errors, without differences between active and sham HF-rTMS stimulation. No significant difference was observed between active and sham stimulation on mean RT. However, only active stimulation resulted in a significant decrease in IIRTV. No effects of stimulation were found for the craving measurements.

CONCLUSION

Our findings suggest that in recently detoxified alcohol-dependent patients, one right-sided HF-rTMS session stabilizes cognitive performance during executive control tasks, implying that active stimulation reduces patients' proneness to attentional lapses.

Parsing the components of the psychomotor syndrome in schizophrenia

OBJECTIVE

Catatonia, extrapyramidal signs, psychomotor slowing, and (motoric) neurological soft signs are well-known psychomotor symptoms in schizophrenia. This study aims at investigating the interrelations between these symptoms. In addition, associations between psychomotor symptoms, clinical symptoms, and cognitive functioning will be studied.

METHOD

An extensive test battery containing psychomotor (Bush Francis Catatonia Rating Scale; St Hans Rating Scale; Salpêtrière Retardation Rating Scale; Neurological Evaluation Scale) and clinical (Positive and Negative Syndrome Scale; Calgary Depression Scale) rating scales as well as instrumental psychomotor tests (Line Copying Task; Finger Tapping Task) and cognitive tasks (Symbol Digit Substitution Test; Stroop Colour Word Test; Continuous Performance Test; Letter Number Sequencing) was administered to a sample of 124 patients with schizophrenia or schizoaffective disorder.

RESULTS

Correlational analyses showed that two clusters emerge from our data: first, a psychomotor poverty cluster referring to the interrelations between catatonia, parkinsonism, psychomotor slowing, and negative symptoms; second, a cluster containing motoric neurological soft signs, which were found to be correlated with cognitive functioning.

CONCLUSION

Psychomotor abnormalities are highly prevalent phenomena in schizophrenia that have to be considered as a heterogeneous construct. However, longitudinal and neurobiological research is needed to further explore the precise nature of the interrelations found in this study.

Impact of one HF-rTMS session on fine motor function in right-handed healthy female subjects: a comparison of stimulation over the left versus the right dorsolateral prefrontal cortex

BACKGROUND

Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive tool to investigate neural conduction in motor processes. Most rTMS research has been conducted by targeting the primary motor cortex. Several studies have also found increased psychomotor speed after rTMS of the dorsolateral prefrontal cortex (DLPFC). However, these studies were mainly performed in psychiatric patients, only targeting the left DLPFC, and often without sham control. Moreover, psychomotor speed is mostly measured based on tasks that also require higher executive functions.

METHODS

Here, we examined the lateralized effect of one sham-controlled high-frequency rTMS session applied to the left or right DLPFC on fine motor function in 36 healthy right-handed females, using the Fitts' paradigm.

RESULTS

We found a significant improvement in psychomotor speed only after actively stimulating the right DLPFC.

CONCLUSION

Our results support the assumption of a right prefrontal neural network implicated in visuomotor behavior and performance processes, and that the improvement in psychomotor speed is not a secondary effect of decreased mood.

No influence of one right-sided prefrontal HF-rTMS session on alcohol craving in recently detoxified alcohol-dependent patients: results of a naturalistic study

BACKGROUND

Prior research in substance dependence has suggested potential anti-craving effects of repetitive transcranial magnetic stimulation (rTMS) when applied to the dorsolateral prefrontal cortex (DLPFC). However, no single sham-controlled session studies applied to the right DLPFC have been carried-out in recently detoxified alcohol-dependent patients. Furthermore, no studies examined the effect of a single HF-rTMS session on craving in these patients' natural habitat.

METHODS

To further investigate the effect of high-frequency (HF)-rTMS of the right DLPFC on alcohol craving, we performed a prospective, single-blind, sham-controlled study involving 36 hospitalized patients with alcohol dependence syndrome. After successful detoxification, patients were allocated receiving one active or one sham HF-rTMS session. The obsessive-compulsive drinking scale (OCDS) was administered to evaluate the extent of craving just before and after the HF-rTMS session (on Friday), on Saturday and Sunday during the weekend at home, and on Monday when the patient returned to the hospital.

RESULTS

One single blind sham-controlled HF-rTMS session applied to the right DLPFC did not result in changes in craving (neither immediately after the stimulation session, nor in patients' natural environment during the weekend).

CONCLUSIONS

One HF-rTMS stimulation session applied to the right DLPFC had no significant effects on alcohol craving in alcohol dependent patients. One such session could have been too short to alter alcohol craving in a sample of alcohol dependent patients.

The Effect of One Left-Sided Preferontal HF-rTMS Session on Emotional Brain Processes

Introduction

Although repetitive Transcranial Magnetic Stimulation (rTMS) is frequently used to examine emotional changes in healthy volunteers, it remains largely unknown how rTMS is able to influence emotion.

Objectives, aims & methods

In this sham-controlled single-blind crossover study using fMRI, we examined in 20 right-handed healthy female volunteers whether a single high frequency (HF)-rTMS session applied to the left dorsolateral prefrontal cortex (DLPFC) could influence emotional processing while focussing on blocks of positively and negatively valenced baby faces. The task instruction was to focus on one's own emotional status elicited by the visual stimuli.

Results

A single HF-rTMS session selectively influenced the processing of positively and negatively valenced baby faces. When positive information was being processed, one active left-sided HF-rTMS session resulted in enhanced neuronal activity in the left superior frontal cortex (Brodmann area 10) and right inferior parietal cortex (Brodmann area 39). When negative information was processed, one active stimulation session attenuated neuronal activity in the right insula, while sham stimulation did not.

Discussion

These observations suggest that after one active HF-rTMS session, psychophysiological reactions while processing withdrawal-related stimuli decrease. The increased neuronal activity while processing of positively valenced baby faces might reflect enhanced task-related processing caused by the neuronal activation of the left DLPFC, which could indicate that females are more able to empathize with the depicted happy baby faces. Our results add further evidence as to why HF-rTMS applied to the left DLPFC might improve mood in depressive populations.

The effect of right-sided prefrontal HF-rTMS on alcohol craving: Preliminary results

Introduction

Repetitive transcranial magnetic stimulation (rTMS) affects neuronal circuits and neurotransmitter systems in the brain. Recent data suggest that this application could diminish ‘craving’ in patients with alcohol dependence.

Objectives and aims

Given these preliminary data, we examined whether one high frequency (HF)- rTMS session over the right dorsolateral prefrontal cortex (DLPFC) would reduce alcohol craving in alcohol dependent patients in their natural habitat.

Methods

After detoxification during hospitalization, 22 current alcohol dependent inpatients were included (8 female, 14 male; age = 49.95 ± 8.82y).

We used a sham-controlled between-subjects design where after randomization patients received under MRI guidance one right-sided DLPFC active HF-rTMS session or sham. In each high-frequency (20 Hz) stimulation session, patients received 1560 pulses at 110 % MT. The obsessive-compulsive drinking scale (OCDS) was collected at baseline, just before and just after the stimulation session on Friday after detoxification and on the three consecutive days following stimulation in patient's natural habitat.

Results

Although the OCDS total score significantly decreased after the detoxification period, one sham-controlled stimulation session did not affect immediate craving measurements. Furthermore, no significant group differences were observed on OCDS total scores when patients were in their natural habitat.

Conclusions

Although the right DLPFC was targeted under MRI guidance, our preliminary results indicate that one sham-controlled HF-rTMS session does not affect craving in recently detoxified alcohol dependent patients. Besides the limited number of patients it could be possible that only one stimulation session could be insufficient to have a subjective effect on craving.

The influence of treatment-resistance on the serotonin 2A receptor in unipolar melancholic depression

Introduction

Major depression is one of the most common mental diseases, and quite a number of patients are resistant to several psychopharmacological interventions, even when applying current treatment guidelines. To date, it remains unclear as to how the serotonergic system is implicated in treatment-resistance found in melancholically depressed patients.

Objectives & aims

In this study, we examined the involvement of post-synaptic 5-HT2A receptors in the pathophysiology of treatment resistance in major depression with 123I-5-I-R91150 SPECT, focusing on the frontal cortex and hippocampus.

Method

15 unipolar antidepressant naïve (ADN) patients and 15 treatment-resistant depressed (TRD) patients, all of the melancholic subtype, matched for age and gender were studied. All subjects were antidepressant free when they underwent a static 123I-5-I-R91150 SPECT scan.

Results

Compared to ADN patients, TRD patients displayed significantly less 5-HT2A receptor binding index (BI) in the dorsal regions of the prefrontal cortex and in the anterior cingulate cortex. No hippocampal 5-HT2A receptor BI differences were observed.

Conclusions

Our results suggest that when confronted with treatment resistance in melancholic depression the 5-HT2A receptors in the DPFC-ACC axis are significantly more down-regulated when compared to depressed ADN patients. This might to some extent explain the observed continued cognitive problems and might reflect the long-term serotonin depletion with reduced neurogenesis in treatment resistant patients.

Intensive HF-RTMS treatment in affective disorders: Sample cases

Introduction

Repetitive transcranial magnetic stimulation (rTMS) on the left dorsolateral prefrontal cortex (DLPFC) is safe and efficient for treatment-resistant depression (TRD). More intensive rTMS protocols could improve clinical outcome.

Objectives

We report on an intensive high frequency (HF)-rTMS treatment protocol in patients unresponsive to current treatment strategies.

Aims

Monitoring effectiveness and tolerability.

Methods

Patients were diagnosed with TRD, schizoaffective disorder, bipolar type or bipolar type I disorder, mixed episode. All were unresponsive to adequate therapy (rTMS excluded).HF-rTMS was administrated on the left DLPFC under MRI guidance. In each 20 Hz stimulation session, the patient received 40 trains of 1.9 seconds duration at 120% of the motor threshold. The 20 HF-rTMS sessions were spread over 4 days (5 times/day), yielding a total of 31,200 stimuli.

Results

There were neither seizures nor important adverse events. The bipolar patient clinically responded (Hamilton Depression Rating Scale (HAMD) from 20 to 9) following treatment day 1. After completing the protocol a week earlier, the TRD patient's HAMD went from 28 to 5. There was a 5 point decrease in the score of the schizoaffective patient. He improved on the brief psychiatric rating subscales blunted affect and emotional withdrawal. No positive symptoms occurred. None of the patients had significant elevations in YMRS scores or in psychomotor activity.

Conclusion

‘Intensively’ targeting the left DLPFC was tolerated and safe. Our results suggest a strategy of HF-rTMS protocols in non-responders to classical treatment. Larger sham-controlled HF-rTMS studies should substantiate these recent findings.

Reduced left subgenual anterior cingulate cortical activity during withdrawal-related emotions in melancholic depressed female patients

BACKGROUND

Research regarding the neurocircuitry in mood disorders suggests an important role for affective information processing of the subgenual part of the anterior cingulate cortex (Cg25: Brodmann area 25).

OBJECTIVE

In this study, we focused on Cg25 neuronal responses in depressed females using a paradigm in which emotions are elicited without explicit cognitive control, relying on the salient nature of the mood inducing stimuli eliciting approach-related emotions (like happiness) or withdrawal-related emotions (like disgust).

METHODS

Twelve treatment-resistant melancholic depressed women and 12 healthy female control subjects were asked to passively view blocks of emotionally valenced baby faces while undergoing functional magnetic resonance imaging (fMRI).

RESULTS

Compared to the healthy females, the depressed patients displayed significantly higher bilateral Cg25 neuronal activities in both emotional conditions. In melancholically depressed women, we found significantly less left-sided than right-sided Cg25 neuronal activity during the withdrawal-related emotions, while right-sided Cg25 activity was comparable for both emotional responses.

CONCLUSIONS

Our results indicate that in depressed women the left Cg25 modulates intense visceral emotional responses to aversive visual stimuli. This could help explain why the left Cg25 provides a valid target region for antidepressant treatment strategies in unipolar melancholic depression.

Asperger syndrome, violent thoughts and clinically isolated syndrome

A young man, 23 years old, with a clinically isolated syndrome (CIS), presented violent thoughts during a neurological consultation. He was diagnosed with Asperger Syndrome based on a psychiatric and (neuro)psychological examination. Possible risk factors for acting-out and the implications for treatment, if CIS would evolve to MS, are discussed based on a review of the literature.

HF-rTMS treatment decreases psychomotor retardation in medication-resistant melancholic depression

Repetitive Transcranial Magnetic Stimulation (rTMS) applied to the left dorsolateral prefrontal cortex (DLPFC) might be a promising treatment strategy for depression. As one of the key features of melancholic depression is disturbances in psychomotor activity, we wanted to evaluate whether HF-rTMS treatment could influence psychomotor symptoms. Twenty antidepressant-free unipolar melancholic depressed patients, all at least stage III medication-resistant, were studied. All were treated with 10 sessions of High-Frequency (HF)-rTMS applied to the left dorsolateral prefrontal cortex (DLPFC) under MRI guidance. Forty percent of the patients showed a reduction of at least 50% on their initial 17-item Hamilton Depression Rating Score (HDRS) scale and were defined as clinical responders. Regardless of clinical outcome HF-rTMS treatment resulted in significant decreases on the Depressive Retardation Rating Scale (DRRS) scores. Although this was an open study in a relatively small sample, our results suggest that HF-rTMS might act on the 'psychomotor' level and these findings could add some further information as to why this kind of treatment can be beneficial for severely depressed patients of the melancholic subtype.