Matti Gärtner

Charité Universitätsmedizin Berlin | Charité · Department of Psychiatry and Psychotherapy

Ketamine is a highly effective antidepressant (AD) that targets the glutamatergic system and exerts profound effects on brain circuits during negative emotional processing. Interestingly, the effects of ketamine on brain measures are sensitive to modulation by pretreatment with lamotrigine, which inhibits glutamate release. Examining the antagonist...

Previous investigations have revealed performance deficits and altered neural processes during working-memory (WM) tasks in major depressive disorder (MDD). While most of these studies used task-based functional magnetic resonance imaging (fMRI), there is an increasing interest in resting-state fMRI to characterize aberrant network dynamics involve...

Neuroimaging studies have identified the anterior cingulate cortex (ACC) as one of the major targets of ketamine in the human brain, which may be related to ketamine’s antidepressant (AD) mechanisms of action. However, due to different methodological approaches, different investigated populations, and varying measurement timepoints, results are not...

Childhood emotional maltreatment (CEM) is a risk factor for the pathogenesis of depressive disorders. However, it is not clear whether CEM is more strongly related to specific symptoms of depression and whether specific traits or cognitive states may mediate the association between CEM and depressive symptoms. In our cross-sectional study, includin...

There is intriguing evidence suggesting that ketamine might have distinct acute and delayed neurofunctional effects, as its acute administration transiently induces schizophrenia-like symptoms, while antidepressant effects slowly emerge and are most pronounced 24 h after administration. Studies attempting to characterize ketamine's mechanism of act...

Introduction: Cognition and emotion are fundamentally integrated in the brain and mutually contribute to behavior. The relation between working memory (WM) and emotion is particularly suited to investigate cognition-emotion interaction since WM is an essential component of many higher cognitive functions. Ketamine affects not only WM but also has...

Intranasal (IN) and intravenous (IV) applications of ketamine have been proven effective for the treatment of depression, but direct comparative trials or meta-analyses on whether both differ in their antidepressant efficacy are lacking. We aimed to meta-analytically compare the short-term efficacy of a single dose of IV and IN ketamine in adult pa...

Background Electroconvulsive therapy (ECT) is an effective treatment for patients suffering from depression. Yet, the exact neurobiological mechanisms underlying the efficacy of ECT and indicators of who might respond best to it remain to be elucidated. Identifying neural markers that can inform about an individual's response to ECT would enable mo...

Background Growing evidence underscores the utility of ketamine as an effective and rapid acting treatment option for major depressive disorder (MDD). However, clinical outcomes vary between patients. Predicting successful response may enable personalized treatment decisions and increase clinical efficacy. Methods We here explored the potential of...

Ketamine exerts its rapid antidepressant effects via modulation of the glutamatergic system. While numerous imaging studies have investigated the effects of ketamine on a functional macroscopic brain level, it remains unclear how altered glutamate metabolism and changes in brain function are linked. To shed light on this topic we here conducted a m...

Establishing symptom-based predictors of electroconvulsive therapy (ECT) outcome seems promising, however, findings concerning the predictive value of distinct depressive symptoms or subtypes are limited; previous factor-analytic approaches based on the Montgomery–Åsberg Depression Rating Scale (MADRS) remained inconclusive, as proposed factors var...

Objective: Mindfulness-based interventions (MBIs) have been found to be a promising approach for the treatment of recurrent courses of depression. However, little is known about their neural mechanisms. This functional magnetic resonance imaging study set out to investigate activation changes in corticolimbic regions during implicit emotion regula...

Depression and early life adversity (ELA) are associated with aberrant resting state functional connectivity (FC) of the default mode (DMN), salience (SN), and central executive networks (CEN). However, the specific and differential associations of depression and ELA with FC of these networks remain unclear. Applying a dimensional approach, here we...

Ketamine was recently approved for treatment resistant depression. However, despite its therapeutic potential, about 50% of patients do not show improvement under this therapy. In this prospective two-site study, we investigated baseline brain structural predictors for rapid symptom improvement after a single subanesthetic ketamine infusion. Furthe...

Electroconvulsive therapy (ECT) is one of the most effective treatments in cases of severe and treatment resistant major depression. 60-80% of patients respond to ECT, but the procedure is demanding and robust prediction of ECT responses would be of great clinical value. Predictions based on neuroimaging data have recently come into focus, but stil...

Background: While electroconvulsive therapy (ECT) is considered the gold standard for acute treatment of patients with otherwise treatment-resistant depression, ketamine has recently emerged as a fast-acting treatment alternative for these patients. Efficacy and onset of action are currently among the main factors that influence clinical decision...

Received: April 09, 2019 Accepted: May 26, 2019 Published online: September 11, 2019 Issue release date: November 2019

Mindfulness-based interventions (MBI) have been found to be a promising approach for the treatment of recurrent courses of depression. However, little is known about their neural mechanisms. This fMRI study set out to investigate activation changes in fronto-limbic regions during implicit emotion regulation. Depressed patients with a recurrent life...

Major depressive disorder (MDD) is associated with abnormal functional interactions among large-scale brain networks. Here we report findings from a randomized, active-controlled trial examining whether mindfulness-based therapy—a clinically effective non-pharmacological treatment for depression—can regulate specific patterns of functional brain co...

Maria Fissler and Emilia Winnebeck also are affiliated with the Department of Psychiatry and Psychotherapy, Charité—Universitätsmedizin Berlin, Campus Benjamin Franklin, Hindenburgdamm 30, 12203 Berlin, Germany

About 20 to 30 percent of patients with Major Depressive Disorder (MDD) do not respond to standard treatment and are considered treatment-resistant. The N-methyl-d-aspartate (NMDA) glutamate receptor antagonist ketamine has demonstrated rapid antidepressant effects in treatment-resistant MDD, but it is unknown whether its acute psychological effect...

Converging evidence suggests that a single sub-anesthetic dose of ketamine can produce strong and rapid antidepressant effects in patients that do not respond to standard treatment. Despite a considerable amount of research investigating ketamine's mechanisms of action, the exact neuronal targets conveying the antidepressant effects have not been i...

Background: Early life stress (ELS) affects facial emotion recognition (FER), as well as the underlying brain network. However, there is considerable inter-individual variability in these ELS-caused alterations. As the hypothalamic-pituitary-adrenal (HPA) axis is assumed to mediate neural and behavioural sequelae of ELS, the genetic disposition to...

Maria Fissler and Emilia Winnebeck also are affiliated at Department of Psychiatry and Psychotherapy, Charité—Universitätsmedizin Berlin, Campus Benjamin Franklin, Berlin, Germany.

Major depressive disorder (MDD) is often accompanied by severe impairments in working memory (WM). Neuroimaging studies investigating the mechanisms underlying these impairments have produced conflicting results. It remains unclear whether MDD patients show hyper- or hypoactivity in WM-related brain regions and how potential aberrations in WM proce...

Affective experience has effects on subjective feelings, physiological indices, entails immediate activity changes in the brain, and even influences brain networks in a protracted manner. However, it is still unclear, how the functional connectivity (FC) interplay between major intrinsic connectivity networks upon affective stimulation depends on a...

Introduction: Early life stress (ELS) impacts emotional and cognitive competences. We aimed to investigate whether the effects of ELS on working memory (WM) performance depend on the valence of the stimuli. Methods: Between January and October 2015, we recruited (N=31) healthy subjects with (N=15) and without (N=16) ELS experiences. Participants...

The error-related negativity (ERN), an evoked-potential that arises in response to the commission of errors, is an important early indicator of self-regulatory capacities. In this study we investigated whether brief mindfulness training can reverse ERN deficits in chronically depressed patients. The ERN was assessed in a sustained attention task. C...

Background: Training in mindfulness has been introduced to the treatment of depression as a means of relapse prevention. However, given its buffering effects on maladaptive responses to negative mood, mindfulness training would be expected to be particularly helpful in those who are currently suffering from symptoms. This study investigated whethe...

The error-related negativity (ERN), an evoked-potential that arises in response to the commission of errors, is an important early indicator of self-regulatory capacities. This study investigated whether brief mindfulness training can reverse ERN deficits in chronically depressed patients. ERN was assessed in a sustained attention task. Chronically...

Background: Training in mindfulness has been introduced to the treatment of depression as a means of relapse prevention. However, from a stress-buffering perspective, mindfulness techniques would be expected to unfold their beneficial effects particularly in those who are currently suffering from symptoms. This study investigated whether a brief an...

Background: Converging evidence suggests that well-being plays an important role in promoting and maintaining mental health across the life span. It has been shown that well-being has a considerable heritable component, but little is known about the specific genes involved. Methods: In this study, we investigated a healthy sample (N = 298) that was...

The spontaneous oscillatory activity in the human brain shows long-range temporal correlations (LRTC) that extend over time scales of seconds to minutes. Previous research has demonstrated aberrant LRTC in depressed patients; however, it is unknown whether the neuronal dynamics normalize after psychological treatment. In this study, we recorded EEG...

Early life stress (ELS) is associated with increased vulnerability for depression, changes to the corticotropin-releasing hormone (CRH) system and structural and functional changes in hippocampus. Single nucleotide polymorphisms in the CRH receptor 1 (CRHR1) gene interact with ELS to predict depression, cognitive functions and hippocampal activity....

Mindfulness-based interventions for the prevention and treatment of depression are predicated on the idea that interoceptive awareness represents a crucial foundation for the cultivation of adaptive ways of responding to negative thoughts and mood states such as the ability to decenter. The current study used a multi-dimensional self-report assessm...

Complex cognitive tasks such as mental arithmetic heavily rely on intact, well-coordinated prefrontal cortex (PFC) function. Converging evidence suggests that frontal midline theta (FMT) oscillations play an important role during the execution of such PFC-dependent tasks. Additionally, it is well-established that acute stress impairs PFC function,...

The ability to predict the behavior of others based on their mental states is crucial for social functioning. Previous studies have provided evidence for the role of Oxytocin (OXT) in enhancing the ability to mentalize. It has also been demonstrated that the effect of OXT seems to strongly depend on socio-cognitive skills with more pronounced effec...

Decline in working memory (WM) functions during aging has been associated with hippocampal dysfunction mediated by age-related changes to the corticotropin-releasing hormone (CRH) system. Recent reports suggest that GG-homozygous individuals of single nucleotide polymorphisms (rs110402 and rs242924) in the CRH receptor 1 (CRHR1) gene show increased...

Background Early life stress (ELS) experience is associated with persisting working memory (WM) deficits, changes to the corticotropin-releasing hormone (CRH) system and structural, functional, and epigenetic changes in the hippocampus. Single nucleotide polymorphisms (SNPs) in the CRH receptor 1 (CRHR1) gene interact with ELS experience to predict...

Rationale: Previous studies have shown that oxytocin (OXT) enhances social cognitive processes. It has also been demonstrated that OXT does not uniformly facilitate social cognition. The effects of OXT administration strongly depend on the exposure to stressful experiences in early life. Emotional facial recognition is crucial for social cognition...

Acute stress impairs prefrontal cortex (PFC) function and has detrimental effects on working memory (WM) performance. Converging evidence from electrophysiological studies suggests a close link between WM processes and frontal theta (FT) activity (4-8 Hz). However, the effect of stress on WM-related FT activity has not been investigated yet. To she...

The main goal of this study was to assess the usability of a tablet-computer-based application (EmoCogMeter) in investigating the effects of age on cognitive functions across the lifespan in a sample of 378 healthy subjects (age range 18-89 years). Consistent with previous findings we found an age-related cognitive decline across a wide range of ne...

Mood states have a strong impact on how we process incoming information. It has been proposed that positive mood facilitates elaborative, relational encoding, whereas negative mood promotes a more careful, stimulus-driven encoding style. Previous electrophysiological studies have linked successful information encoding to power increases in slow (<8...

Rationale: The neuropeptide oxytocin (OXT) has been shown to modulate a variety of human social behaviors. However, little is known about its impact on emotional memory processing. Previous research demonstrated both memory-enhancing and memory-impairing oxytocinergic effects. Methods: We investigated the influence of a single (prior to encoding...

MindArt is a computer-animated film for the Bernstein Conference 2011 that shows artistic visualizations by using real EEG data from the 2011 MusicMind 1 experi-ment. The field of neuroscience still uses traditional visualization methods, such as wave charts / diagrams and heatmaps, to interpret abstract data like brain waves or neuronal streams. H...

Methods of statistical machine learning have recently proven to be very useful in contemporary brain-computer interface (BCI) research based on the discrimination of electroencephalogram (EEG) patterns. Because of this, many research groups develop new algorithms for both feature extraction and classification. However, until now, no large-scale com...

A Brain–Computer Interface (BCI) provides a new communication channel for severely disabled people who have completely or partially lost control over muscular activity. It is questionable whether a BCI is the best choice for controlling a device if partial muscular activity still is available. For example, gaze-based interfaces can be utilized for...

This chapter introduces a formal categorization of BCIs, according to their key characteristics within HCI scenarios. This comprises classical approaches, which we group into active and reactive BCIs, and the new group of passive BCIs. Passive BCIs provide easily applicable and yet efficient interaction channels carrying information on covert aspec...