Internalizing disorders, encompassing conditions such as depression, anxiety, and related affective dysregulations, represent a substantial clinical challenge due to their heterogeneous presentations and variable responses to treatment. Traditionally, therapeutic approaches have relied heavily on symptomatology and behavioral assessments, which often offer limited predictive power about treatment success. This knowledge gap has driven researchers to probe the neural substrates involved in emotion regulation—the brain’s capacity to modulate affective states—to identify objective markers that could predict individual outcomes.

Central to this review is the discussion of brain circuits implicated in emotion regulation, including but not limited to the prefrontal cortex, amygdala, anterior cingulate cortex, and insula. These regions collectively orchestrate the appraisal, modulation, and expression of emotional experiences. Notably, neuroimaging studies employing functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) have illuminated patterns of activation and connectivity within these networks that correlate with symptom severity and responsiveness to pharmacological and psychotherapeutic interventions.

One of the key insights highlighted is the role of the dorsolateral prefrontal cortex (dlPFC) in exerting top-down control over limbic structures such as the amygdala. Enhanced dlPFC engagement during emotion regulation tasks has been associated with better treatment response, suggesting that efficient cognitive control mechanisms are crucial for clinical improvement. Conversely, hypoactivation in these control areas, or hyperreactivity in the amygdala, may predict resistance to traditional therapies, thereby urging the exploration of adjunctive treatments targeting these neural circuits more directly.

The review also underscores the promise of resting-state connectivity analyses, which evaluate the synchronization of brain activity patterns in the absence of task demands. Aberrant connectivity within the default mode network (DMN) and salience network has emerged as a hallmark of many internalizing disorders. Disruptions in these networks could hinder adaptive emotion regulation by impairing self-referential processing and the allocation of attention to salient emotional stimuli. Tracking these disruptions longitudinally offers a non-invasive window into treatment progress and potential relapse risk.

Importantly, Klumpp and colleagues emphasize the transdiagnostic value of neural markers in internalizing disorders. They argue that despite categorical distinctions between anxiety, depression, and related conditions, overlapping neurobiological signatures can predict common pathways to recovery. This perspective aligns with the Research Domain Criteria (RDoC) framework, promoting dimensional and mechanistic approaches over traditional diagnostic boundaries.

Another critical dimension explored in the paper relates to personalized medicine. The integration of neural predictors with clinical and demographic data creates a multifaceted profile that can guide individualized treatment plans. For instance, patients exhibiting specific patterns of brain activity might benefit more from cognitive-behavioral therapy focusing on cognitive reappraisal, while others might respond preferentially to pharmacotherapies targeting neurotransmitter systems connected to emotion regulation circuits.

Moreover, the authors shed light on emerging technologies poised to refine prediction models further. Machine learning algorithms trained on multimodal datasets—including neuroimaging, genetic, and behavioral metrics—have begun to identify complex patterns invisible to traditional statistical approaches. These tools hold the promise of enabling clinicians to anticipate treatment response with unprecedented accuracy, reducing trial-and-error periods that currently burden patients and healthcare systems.

The review also navigates the challenges inherent in translating these neuroscientific discoveries into clinical practice. Variability in imaging protocols, small sample sizes, and the heterogeneity of study populations limit the generalizability of findings. Klumpp et al. advocate for large-scale, multicenter collaborations with standardized methodologies to surmount these barriers and validate identified biomarkers robustly.

Emotion regulation itself is dissected not only as a therapeutic target but as a dynamic process influenced by developmental trajectories, environmental exposures, and genetic predispositions. The authors argue for longitudinal studies integrating these factors to unravel how they interact to shape neural function and treatment outcomes over time, thus informing early intervention strategies.

Additionally, the review highlights novel pharmacological agents and neuromodulation techniques, such as transcranial magnetic stimulation and deep brain stimulation, which modulate specific neural circuits implicated in emotion regulation. Understanding the neural signatures predictive of responsiveness to these advanced interventions could revolutionize treatment paradigms for refractory cases.

Crucially, the narrative synthesizes evidence that incorporating emotion regulation training into treatment regimens measurably enhances neural plasticity and clinical response. Interventions such as mindfulness-based stress reduction and emotion-focused therapies can realign dysfunctional neural circuitry, suggesting that neural markers might also serve as biomarkers for the mechanistic processes underlying therapeutic change.

Furthermore, Klumpp and colleagues stress the ethical considerations in deploying neuroimaging-derived predictors. The potential for stigmatization or misclassification necessitates rigorous safeguards, transparency in data interpretation, and equitable access to emerging diagnostic tools, ensuring that advances in neuroscience translate into societal benefit without unintended harm.

Advancing this field will require interdisciplinary collaboration melding psychiatry, neuroscience, data science, and bioethics. The authors call for an integrative research agenda that bridges basic and clinical science to establish neural predictors not only as prognostic tools but also as guides for novel, mechanism-based interventions tailored to individual neurobiological profiles.

This comprehensive review epitomizes the exciting frontier where neuroscience intersects with clinical psychiatry, illuminating how understanding the neural underpinnings of emotion regulation can transform treatment outcomes in internalizing disorders. By unmasking the brain’s predictive signals, the study lays the foundation for a future where mental health care is defined by precision, personalization, and profound scientific insight.

Subject of Research: Neural predictors of treatment outcome through emotion regulation in internalizing disorders

Article Title: Neural predictors of treatment outcome through emotion regulation in internalizing disorders: a narrative review

Article References:
Klumpp, H., Davey, D. & Langenecker, S.A. Neural predictors of treatment outcome through emotion regulation in internalizing disorders: a narrative review. Transl Psychiatry (2026). https://doi.org/10.1038/s41398-026-03908-8

Image Credits: AI Generated

DOI: https://doi.org/10.1038/s41398-026-03908-8

The claustrum, a slender and enigmatic sheet of neurons nestled deep beneath the cortex, has been postulated to act as a central hub integrating various neural signals. It is endowed with a high density of receptors that psychedelics commonly target, yet its precise functional contributions remain enigmatic. Ortinski’s study utilized male rat models to explore how psychedelic compounds influence the claustrum neurons, particularly those projecting to the anterior cingulate cortex (ACC), a cortical area critically implicated in cognitive processing and psychiatric conditions such as depression, anxiety, and schizophrenia.

Employing advanced electrophysiological recording techniques, the researchers observed that psychedelic exposure reversed the typical polarity of long-term synaptic plasticity within these claustrum neurons. Under normal physiological conditions, activating these neurons produced a form of synaptic weakening known as long-term depression (LTD). Intriguingly, psychedelic treatment shifted this response to long-term potentiation (LTP), a process fundamentally associated with strengthening synaptic connections and the encoding of memories.

This reversal of synaptic plasticity polarity was specific to the claustrum neurons projecting onto the ACC and did not manifest in the absence of psychedelic administration. Such specificity suggests that psychedelics uniquely engage the claustrum-ACC circuitry to modulate cognitive functions. The implications of these findings are profound, as synaptic plasticity stands at the core of how neurons adapt and reorganize in response to experiences, potentially underpinning the long-lasting therapeutic effects observed in clinical settings.

Ortinski and his team theorize that the hallmark intensely vivid and memorable experiences during psychedelic ‘trips’ might arise from this mechanism. By shifting synaptic plasticity to favor potentiation, psychedelics could intensify the encoding of specific neural circuits, thereby consolidating therapeutic memories that alleviate psychiatric symptoms. This aligns with psychological models suggesting that the transformative effects of psychedelics hinge on heightened experiential salience and emotional processing.

Moreover, the research adds a nuanced layer to the understanding of serotonin receptor signaling—a major biochemical substrate for psychedelics. The observed plasticity shifts are likely mediated through 5-HT2A receptor activation within the claustrum, influencing downstream intracellular cascades that regulate synaptic strength. This aligns with broader themes in neuropharmacology linking serotonin receptor modulation to psychiatric symptomatology and therapeutic recovery.

The findings challenge previous conceptions that psychedelics simply disrupt normal brain activity. Instead, they reveal a sophisticated modulation of synaptic dynamics within specific neural circuits important for cognition and emotion regulation. Such insights could pave the way for targeted therapies that harness psychedelic mechanisms without necessarily inducing hallucinogenic effects, potentially broadening the therapeutic toolkit for intractable mental illnesses.

Future research will need to investigate whether this polarity reversal mechanism operates similarly in humans and across different psychiatric diseases. Additionally, understanding how this synaptic plasticity modulation interacts with other brain regions involved in mood regulation and executive function could illuminate the systemic effects of psychedelic therapies. Ortinski’s work sets the stage for these investigations, providing a crucial piece of the complex puzzle linking brain plasticity, cognition, and mental health.

Ultimately, this study exemplifies the vibrant intersection of molecular neuroscience, pharmacology, and psychiatry. By elucidating how psychedelics reverse long-term plasticity polarity in a brain region integrally connected to cognitive control, it offers a compelling explanation of the neurobiological underpinnings of psychedelic-assisted therapy. This could herald a new era of science-driven, mechanism-based psychiatric treatments grounded in the biology of brain plasticity.

As the societal and clinical acceptance of psychedelic research accelerates, such mechanistic work is vital. It not only demystifies the action of these compounds but also helps refine their therapeutic use, facilitate regulatory approval, and tailor interventions to maximize benefit and minimize risks. The claustrum, long regarded as a mysterious cerebral player, is now illuminated as a key substrate in the dialogue between psychedelics and psychiatric symptom relief.

Pavel Ortinski and colleagues’ study in eNeuro represents a landmark in psychedelic neuroscience. By revealing how psychedelics fundamentally alter synaptic communication within the claustrum-ACC pathway, it opens a new window onto the neurophysiological basis of cognition and emotion modulation. This knowledge will undoubtedly inspire further research aimed at harnessing the plastic potential of the brain to treat psychiatric disorders in novel and effective ways.

As neuroscience unwraps these layers of complexity, the future of psychiatric medicine appears increasingly intertwined with the delicate art of modulating brain plasticity. Psychedelic compounds, through mechanisms such as those elucidated by Ortinski’s team, may finally realize their vast therapeutic promise, transforming mental health care for millions worldwide.

Subject of Research: The effects of psychedelics on synaptic plasticity in claustrum neurons projecting to the anterior cingulate cortex.

Article Title: Psychedelics Reverse the Polarity of Long-Term Synaptic Plasticity in Cortical-Projecting Claustrum Neurons

News Publication Date: 27-Oct-2025

Web References:
DOI: 10.1523/ENEURO.0047-25.2025

Keywords: Psychiatric disorders, Medical treatments, Drug therapy, Serotonin, Serotonin receptor signaling