Skip to content

Simone Grimm

14 papers in the library · 494 citations · publishing 2011-2026

Papers

Sort Most recent Most cited

Ketamine’s impact on rumination-related brain dynamics: insights from a randomized controlled fMRI trial

Translational Psychiatry August 18, 2026 Marvin Sören Meiering, David Weigner, Matti Gärtner et al.

Rumination has been associated with aberrant dynamics of a coactivation pattern (CAP) comprising the default mode (DMN) and frontoparietal (FPN) networks. Ketamine exerts rapid antidepressant effects and may influence these dynamics via glutamatergic mechanisms. In a randomized, double-blind, placebo-controlled fMRI study, we investigated ketamine's effects on dynamic CAPs associated with...

Functional connectivity alterations of the pregenual anterior cingulate cortex by ketamine and the modulation by lamotrigine.

Journal of psychopharmacology (Oxford, England) June 19, 2025 David Weigner, Marvin Sören Meiering, Anne Weigand et al.

Neuroimaging studies have linked the beneficial effects of subanaesthetic ketamine doses in psychiatric conditions characterized by chronic stress pathology (CSP) to altered functional connectivity (FC) within the pregenual anterior cingulate cortex (pgACC). Previous research indicates a potential role of glutamate concentration in FC changes; however, the precise relationship between glutamate...

Functional activity and connectivity signatures of ketamine and lamotrigine during negative emotional processing: a double-blind randomized controlled fMRI study.

Translational Psychiatry October 14, 2024 Marvin S Meiering, David Weigner, Matti Gärtner et al. 4 citations

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 antagonistic effects of ketamine and lamotrigine on...

Negative emotionality shapes the modulatory effects of ketamine and lamotrigine in subregions of the anterior cingulate cortex.

Translational Psychiatry June 18, 2024 Matti Gärtner, Anne Weigand, Marvin Sören Meiering et al. 1 citation

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 consistent, and the functional significance of...

Predicting Antidepressant Effects of Ketamine: the Role of the Pregenual Anterior Cingulate Cortex as a Multimodal Neuroimaging Biomarker

The International Journal of Neuropsychopharmacology August 10, 2022 Anne Weigand, Matti Gärtner, Milan Scheidegger et al. 22 citations

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 pregenual anterior cingulate cortex (pgACC)...

Acute effects of ketamine on the pregenual anterior cingulate: linking spontaneous activation, functional connectivity, and glutamate metabolism

European Archives of Psychiatry and Clinical Neuroscience January 12, 2022 Matti Gärtner, Anne Weigand, Milan Scheidegger et al. 13 citations

Abstract 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 multimodal imaging study in healthy...

Increase in thalamic cerebral blood flow is associated with antidepressant effects of ketamine in major depressive disorder

The World Journal of Biological Psychiatry January 5, 2022 Matti Gärtner, Mischa de Rover, Lena Václavů et al. 11 citations

Ketamine is a promising treatment option for patients with Major Depressive Disorder (MDD) and has become an important research tool to investigate antidepressant mechanisms of action. However, imaging studies attempting to characterise ketamine's mechanism of action using blood oxygen level-dependent signal (BOLD) imaging have yielded inconsistent results- at least partly due to intrinsic...

Effects of Mindfulness Training on Emotion Regulation in Patients With Depression: Reduced Dorsolateral Prefrontal Cortex Activation Indexes Early Beneficial Changes

Psychosomatic Medicine May 5, 2021 Thorsten Barnhofer, Tim Jonas Reeß, Maria Fißler et al. 24 citations

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 regulation. METHODS: Depressed patients with a...

Mindfulness-based therapy regulates brain connectivity in major depression

May 29, 2019 Michael Lifshitz, Matthew D. Sacchet, Julia M. Huntenburg et al. 1 citation

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 can regulate specific patterns of resting-state functional connectivity in clinically depressed patients. We show that a brief, clinically effective mindfulness...

Differential effects of rumination and distraction on ketamine induced modulation of resting state functional connectivity and reactivity of regions within the default-mode network

Social Cognitive and Affective Neuroscience April 13, 2016 Mick Lehmann, Erich Seifritz, Anke Henning et al. 58 citations

Distraction and rumination are distinct response styles that determine how an individual deals with negative thoughts and feelings. Rumination is accompanied by an elevated self-focus, which is associated with increased resting state functional connectivity and decreased reactivity within the default mode network. Interestingly, the NMDA receptor antagonist ketamine reduces functional...

Ketamine administration reduces amygdalo‐hippocampal reactivity to emotional stimulation

Human Brain Mapping February 25, 2016 Milan Scheidegger, Anke Henning, Martin Walter et al. 78 citations

Increased amygdala reactivity might lead to negative bias during emotional processing that can be reversed by antidepressant drug treatment. However, little is known on how N-methyl-d-aspartate (NMDA) receptor antagonism with ketamine as a novel antidepressant drug target might modulate amygdala reactivity to emotional stimulation. Using functional magnetic resonance imaging (fMRI) and...

Ketamine Decreases Resting State Functional Network Connectivity in Healthy Subjects: Implications for Antidepressant Drug Action

PLoS One September 24, 2012 Milan Scheidegger, Martin Walter, Mick Lehmann et al. 282 citations

Increasing preclinical and clinical evidence underscores the strong and rapid antidepressant properties of the glutamate-modulating NMDA receptor antagonist ketamine. Targeting the glutamatergic system might thus provide a novel molecular strategy for antidepressant treatment. Since glutamate is the most abundant and major excitatory neurotransmitter in the brain, pathophysiological changes in...

Acute ketamine administration modulates glutamatergic neurotransmission and functional brain activation in prefrontal cortex implications for major depression

Pharmacopsychiatry September 1, 2011 Milan Scheidegger, Anke Henning, Martin Walter et al.

Background: Ketamine is a potent NMDA receptor antagonist with rapid antidepressant properties at subanaesthetic doses. This multimodal imaging study reveals the effects of a subanaesthetic ketamine infusion on fMRI-BOLD responses during an emotional processing task and their relationship to glutamatergic metabolite concentrations in the pregenual anterior cingulate cortex (PACC) assessed by...

Emotionalcognitive processing and brain metabolism after pharmacological challenge with ketamine

Pharmacopsychiatry September 1, 2011 Simone Grimm, Milan Scheidegger, Anke Henning et al.

Ketamine is a potent glutamatergic NMDA receptor antagonist with rapid antidepressant properties, thus providing a valuable research tool for the investigation of the neurobiology of major depressive disorder (MDD). Increasing evidence underscores the role of glutamate dependent neuroplasticity and glutamatergic neurotransmission and metabolism in the pathophysiology of MDD. This multimodal...