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Mechanistic Links Between Early Adversity and Suicide: A Neuropsychoanalytic Model

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26 August 2025

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27 August 2025

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Abstract

This article employs a holistic, mechanistic model explaining how early life adversity (ELA) leads to increased suicide risk. It maps the internalization and introjection processes from psychoanalytic object relations theory with circuits involving the amygdala, hippocampus, and medial prefrontal cortex ( mPFC ) within the framework of memory engrams and system consolidation. The model emphasizes neuroplastic and epigenetic reprogramming mediated by the serotonergic apparatus (specifically 5-HT1A and 5-HT2A receptors) and the HPA axis as the biological foundation. Using a dual-aspect monism approach and theoretical integration based on Gundersen’s six criteria, it suggests that ELAs strengthen negative internal objects through norepinephrine-glucocorticoid-mediated synaptic traces, site-specific DNA methylation, PFC regulatory attenuation, and amygdala hyperreactivity. These changes disrupt social homeostasis, lead to the generalization of autobiographical memory, affect pain processing, and increase feelings of loneliness, which contribute to the schemas of “Thwarted Belongingness” and “Perceived Burdensomeness” in Joiner’s interpersonal theory of suicide. Over time, repeated stress raises allostatic load, resulting in permanent set-point shifts and an increased capacity for “deliberate/lethal” behaviors. This comprehensive framework supports a shift from descriptive to mechanistic psychiatry, offering a theoretical and practical guide to understanding the neurobiological development of suicide.

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Introduction

According to the World Health Organization (2025), suicide takes over 720,000 lives each year and is the third leading cause of death among those aged 15-29. Traditional psychiatric diagnostic systems treat suicide as a symptom-based phenomenon, often overlooking underlying developmental and neurobiological phenomena (Gay, 2025). Although these systems are useful for clinical decision-making, they fail to address how early life experiences contribute to long-term suicide vulnerability.
ELAs are one of the most potent predictors of suicidal behavior (Angelakis et al., 2019; Kuhlman et al., 2017). A meta-analysis of 337,185 individuals revealed that the risk of suicide attempts among those with sexual abuse was conferring an OR=3.42, and emotional abuse an OR=2.21 (Angelakis et al., 2020). Critically, this relation follows a dose-response gradient: seven or more adversities increase the risk of suicide by 51-fold in adolescents and 29.8-fold in adults compared to controls, while two ELAs increase the risk by 6.3-fold in adolescents and 3.1-fold in adults (Dube et al., 2001). These gradients highlight the need for etiological models that incorporate biological infrastructure, context, stress timing, and accumulation beyond descriptive psychiatry.
Traditional systems view suicide as observable, near-term causes like depression and substance use (Oliogu & Ruocco, 2024). While some link early trauma to suicide, they lack detail on how adversity becomes biologically embedded (O’Connor & Kirtley, 2018). Mechanistic views like allostatic load offer insight into stress-induced neuroplasticity but do not clarify how experiences form enduring distortions leading to suicidal behavior (McEwen, 2017). We aim to advance these models with the psychoanalytic object relations construct. Object relations theory suggests early caregiving shapes internalized self- and other representations, yet it lacks discussion on the neural basis of these internalized “object relations’ (O. F. Kernberg, 1976, p. 29).
In this review, we adopt a dual-aspect monism perspective, considering psychoanalytic and neurobiological explanations as complementary descriptions of the same underlying reality (Solms & Turnbull, 2018). By integrating object relations theory with current neuroscientific research on memory engrams and neural plasticity, we aim to clarify how negative early life experiences become embedded in the brain and contribute to suicidal behaviors in adulthood. First, we will synthesize the neurobiological basis of the internalization process in object relation theory within the framework of dual-aspect monism, progressing towards the molecular biological level. Our focus will be on the connection between the serotonergic system, suicide, and early life adversity.

Internalization and Its Neurobiology

Integration of psychoanalytic object relations with contemporary neuroscience is a significant challenge in interdisciplinary science. This challenge arises not only from procedural differences but also from differences in psychoanalytic and empirical neuroscience frameworks. This section systematically assesses the complexity using six criteria from Gundersen’s interdisciplinary framework: consistency, supervenience, mechanism, domain overlap, conceptual refinement, and cross-disciplinary confirmation (Gundersen, 2022). We will explore the idea of introjection in object relations theory using Gundersen’s six criteria of integration. This concept is key to understanding how early life adversities leave memory marks and how these impressions impact long-term development. While writing this section, we acknowledge that not all object relation concepts are fully explained by current neuroscience, but the overlapping areas are especially illuminating.

Consistency

Consistency involves demonstrating that psychoanalytic ideas can logically align with neurological frameworks (Gundersen, 2022). Object relations theory posits that early caregiver interactions involve the internalization of an object (the caregiver) along with associated self-representation associated with affect (O. F. Kernberg, 1976, p. 29). Recent research on memory engrams might offer a theoretical basis for this link. Engrams control the formation and recall of emotionally significant memories, involving structures such as the amygdala, hippocampus, and mPFC, which are crucial in categorizing and storing emotionally charged stimuli (Kitamura et al., 2017). The hippocampus encodes contextual details, while the amygdala assigns emotional significance (Kitamura et al., 2017).
Additionally, afferents from these regions contribute to engram formation in the prefrontal cortex (Kitamura et al., 2017). Once prefrontal engrams are established, hippocampal engrams regress, but they do not disappear (Guskjolen et al., 2018). When encountering salient stimuli, the organism activates the prefrontal cortex, which subsequently stimulates the amygdala to produce a response (Kitamura et al., 2017). The neural systems involved in processing emotionally significant stimuli, like fear or pleasure, and how they are encoded form the neurobiological foundation of social memory as discussed in psychoanalytic theory.

Supervenience

Philosophical supervenience asserts that there can be no mental change without an accompanying physical change (Gundersen, 2022). Object relations suggest that intense and lasting experiences tend to have a stronger influence on a person’s life (Svrakic & Zorumski, 2021). On the other hand, research indicates that the intensity of an event that encodes negative states is directly related to the strength of the resulting engrams (Choi et al., 2018). Engram formation signifies both the ability to recall and the underlying neurological changes (Josselyn & Tonegawa, 2020). In the case of the BLA, engram formation has been noted in a fear-conditioned context (Abatis et al., 2024). Using this perspective, splitting may be understood as a neurobiological rather than just psychological defense. Neurobiological insights imply it may involve increased activity in the amygdala and reduced impulse control from the prefrontal cortex (Cullen et al., 2011). The PFC does not regulate the increased amygdala activity during splitting, leading neurons tuned to positive and negative valence to trigger impulses (Zhang et al., 2020). Increased activation from the basolateral to the central amygdala is observed in individuals with borderline traits (N. T. Hall & Hallquist, 2023). Overall, this perspective highlights both the psychological conflicts and the neural processes underlying pathological splitting.

Mechanistic Overlaps

The term “mechanism” refers to how a correlation occurs, rather than the correlation itself (Gundersen, 2022). For interdisciplinary integration, early experiences shape lasting behavioral patterns at both the psychoanalytic and neurobiological levels. Object relations theory suggests that early experiences remarkably influence the course of development (Klein, 1984, pp. 87–88). Likewise, neurobiological studies show that these experiences form attractor networks in the brain that strengthen over time (Boscaglia et al., 2023). Additionally, Newcombe and Fox (1994) demonstrated that children respond physiologically to images of former friends even if they do not explicitly recognize them, indicating that unconscious memories can influence behavior. Optogenetic studies also confirm that these memories can be reactivated at the neural level (Guskjolen et al., 2018). Furthermore, Wu et al. (2021) showed that the medial septum–hippocampus circuit, via serotonergic modulation, maintains social memory through experience-driven synaptic plasticity. Collectively, these findings suggest a potential mechanistic link between psychoanalytic theory and neuroscience, beyond mere metaphor.

Interdisciplinary Confirmation

Interpretation should be anchored in the discipline that best accounts for the phenomenon within a dynamic framework: for instance, psychoanalytic views on autism have shifted toward neurodevelopmental models (Gundersen, 2022). Similarly, psychoanalysis and neuroscience converge in the process of memory reconsolidation: when an emotional memory is retrieved, it becomes temporarily unstable and open to modification before it is reconsolidated. In Högberg et al.’s model (2011), the PRM-complex protocol begins by activating positive affect to establish safety. Next, negative memories are then explored in three stages within the reconsolidation window: perception, response, and motor drive (Högberg et al., 2011). Ultimately, “repair fantasy” and future projection foster the formation of new, non-fearful memory traces (Högberg et al., 2011). This empirical model demonstrates that interdisciplinary research may provide validation by integrating psychoanalytic concepts with neural mechanisms.

Domain Overlap

Domain overlap explores how phenomena are addressed within the interdisciplinary framework of two fields (Gundersen, 2022). Rapid cortical growth during early life, driven by glial and synaptic levels, aligns with the critical window emphasized in the attachment theory. (Bowlby, 1951, p. 53; Tau & Peterson, 2010) This critical period encompasses increased sensitivity to experiences, and these experiences shape further behaviors (Bowlby, 1951, p. 53; Main et al., 1985). For example, early maternal behaviors lead to similar behavioral outcomes (Francis et al., 1999). This aligns with the “garbage in, garbage out” principle in artificial intelligence: the more precise the input, the more accurate the output (Hanson et al., 2023).

Conceptual Refinement

Conceptual refinement suggests that instead of simplifying a psychoanalytic idea into a vague single explanation, different underlying psychological and neurobiological mechanisms should be identified to create a more testable concept (Gundersen, 2022). For instance, through splitting, a person may perceive the world in binary terms, either black or white (O. Kernberg, 1967). Because of splitting, they see the other person as either devalued or omnipotent (O. Kernberg, 1967). Early life stress can result in lasting alterations to the development of the HPA axis (van Bodegom et al., 2017). These modifications might lead to the engram expansion (Lesuis et al., 2021). Additionally, the diminished regulatory function of the PFC leads to the direct expression of generalized emotions (Etkin et al., 2011). Therefore, biased thinking can emerge when PFC-mediated emotion regulation is disrupted (Lapate et al., 2017).
The clinical significance of this integrative model lies in how disrupted object relations become biologically embedded and ultimately resulting in suicidal behavior. Within Joiner’s interpersonal theory of suicide, the combination of thwarted belongingness (“I am alone”) and perceived burdensomeness (“I am a burden”) together contribute to suicidal desire (Van Orden et al., 2010). However, acting on this desire requires having the capacity for suicide, which is developed through a reduced perception of pain (Van Orden et al., 2010).
The social homeostasis model’s detector responds to environmental stimuli, with social memory refining familiar social cues (Lee et al., 2021). Loneliness can be alleviated by increasing social interactions based on past experiences (Zhaoyang et al., 2022). Extended maternal separation results in stages of protest, despair, and detachment; the longer the separation, the higher the risk of ongoing impairment and impaired social relationships (Bowlby, 1979, p. 48; H. Li et al., 2024).
Williams & Broadbent (1986) demonstrated that individuals who attempt suicide tend to show more memory overgeneralization. Childhood sexual abuse is also linked to increased memory overgeneralization (Kuyken & Brewin, 1995). The effect size for the relationship between trauma and overgeneralized memory was 1.13 (IQR=0.72) (J. M. G. Williams et al., 2007). This impairment can hinder social problem-solving and diminish the capacity to envision future events, especially in depressed and suicidal populations (J. M. G. Williams et al., 2007).
Within a psychoanalytic framework, a negative internalized object leads to a negative self-concept (Klein, 1984, pp. 230–231). A meta-analysis with 255,334 sample size showed a modest but consistent negative association between early life adversity and negative self-image (Melamed et al., 2024). Another meta-analysis found a significant inverse relationship between self-esteem and suicidal ideation (Buecker et al., 2025). Overall, challenges in social problem-solving and a negative self-view contribute to feelings of burdensomeness; when combined with ELA-related impaired pain processing (Pouget & Vetere, 2023), they collectively contribute to suicidal acts. This suggests how maladaptive engrams in critical brain circuits during early development can have profound effects on mental health outcomes, highlighting the clinical importance of understanding object relations from a neurobiological framework via the dual-aspect monist perspective

Molecular Encoding of Early Life Adversity

Homeostatic systems can undergo shifts in set points that depend on time and context, as observed in the neurological, pulmonary and renal system (J. E. Hall & Guyton, 2016, p. 4; Matthews & Tye, 2019; Schanzenbächer et al., 2018). One long-term regulation involves controlling protein synthesis, but excessive activity can lead to maladaptive conditions (Kumar et al., 2015, pp. 32–38).
Stress-induced engram formation is run by norepinephrine and glucocorticoids (Brosens et al., 2024). During acute stress, the increase in norepinephrine (NE) activates β-adrenergic receptors (β-ARs), which then stimulate CaMKII and the Gs–cAMP–PKA pathway (Gereau & Conn, 1994; Larsen et al., 2023; Pittaluga & Raiteri, 1992; Roberson et al., 1999). This process triggers gene transcription via CREB, a crucial transcription factor for synaptic plasticity (Benito & Barco, 2010). Furthermore, NE lowers the threshold for long term potentiation LTP and promotes the spread of synaptic signaling molecules to adjacent synapses (Dittmer et al., 2019; O’Dell et al., 2015). While glucocorticoids influence coding through mineralocorticoid receptors during the acute phase, their effects over hours and days involve glucocorticoid receptors, leading to increased levels of CaMKII, BDNF, CREB, MAPK, EGR-1, and mTOR (Brosens et al., 2024; Karst et al., 2005; C.-C. Wang & Wang, 2009). PKMζ, which is essential for the maintenance of memory, encounters reduced inhibition when PIN1 levels decrease during LTP (Baltaci et al., 2019). In rodent studies, PIN1 levels are high during the early postnatal period, which suppresses PKMζ activity (Jiang et al., 1994; Nakamura et al., 2012). As a result, sustained, learning-related synaptic strengthening is not possible. Over time, PIN1 levels begin to decrease, and PKMζ activity increases (Opendak et al., 2018).
Furthermore, post-translational histone modifications are important for short-term memory, while cortical DNA methylation, mediated by DNA methyltransferases (DNMTs), is crucial for long-term memory (Halder et al., 2016). Early-life adversity increases DNMT3A levels in the prefrontal cortex, which is associated with memory formation, but leads to a decrease in the hippocampus (Urb et al., 2019; X. Wang et al., 2022). In the amygdala, early maternal separation combined with a secondary stressor (a senescent male) produced sustained increases in DNMT3A expression that persisted into adulthood (Karen & Rajan, 2019). Accordingly, DNA methylation patterns are region-specific and scale with the severity of the adverse experience.
ELAs influence numerous neurobiological systems involved in long-term memory formation, leading to lasting structural and functional modifications (Wisłowska-Stanek et al., 2021). Significantly, these encompass the HPA axis, the serotonergic system, neurotrophins, glutamatergic and GABAergic neurotransmission, inflammation, and cholesterol metabolism (Bourgognon & Cavanagh, 2020; Izquierdo & Medina, 1997; Lesuis et al., 2025; Pfrieger, 2003; Yang et al., 2020). Among these, the serotonergic system has been extensively researched for its association with suicidal behavior and contributes to negative valence-related memory consolidation under stress (Baratta et al., 2016). Although serotonin exhibits a dual role in learning processes, it is especially vital in encoding aversive stimuli (Scholl et al., 2017; Tortora et al., 2023a). Experimental findings supporting this perspective. For instance, silencing serotonergic neurons in the dorsal raphe nucleus disrupts fear extinction, as the organism is unable to process signals such as “negative expectation errors” (e.g., the absence of the anticipated punishment) (Berg et al., 2014). Furthermore, serotonin release increases following aversive stimuli such as shock, resulting in heightened freezing and fear-related behaviors (Akbar et al., 2023; Howard et al., 2019; Sengupta & Holmes, 2019). A systematic review investigating the influence of serotonin modulators on fear learning and memory in humans found that an acute elevation of serotonergic activity elicits enhanced fear responses; conversely, an acute inhibition of 5-HT2 receptors facilitates fear extinction and reduces skin conductance response (Tortora et al., 2023b).
On the other hand, early life stress reprograms plasticity-related responses within the serotonergic system. In the mPFC, 5-HT1A receptors exhibit functional impairment and disrupted hyperpolarization following such stress, whereas for 5-HT2A receptors, antagonism in the PL-PFC prevents both the increase in 5-HT2A mRNA and the sustained elevation of the plasticity-related Arc mRNA (Benekareddy et al., 2010; Kimura et al., 2011). These findings demonstrate that both receptor subtypes play critical roles in plasticity mechanisms and that early life stress disrupts these responses. Interestingly, after maternal separation, stimulating the 5-HT2A receptors in the mPFC leads to heightened responses in both behavioral and brain plasticity-related genes (Sood et al., 2018). This sets the stage for long-term changes in the neural circuit alterations (Sood et al., 2018). Early life adversity-related serotonergic alterations, which extend beyond the 5-HT1A and 5-HT2A receptors to include alterations observed in 5-HT1B receptors, the serotonin transporter (SERT), and overall serotonin levels (Alcántara-Alonso et al., 2024; de Souza et al., 2020; Gardner et al., 2009).
ELAs are not restricted to transient physiological stress reactions; rather, they induce enduring molecular, cellular, and circuit reconfigurations that may persist throughout an individual’s lifetime. These reorganizations entail concurrent and interactive modifications directly associated with learning and mood regulation, leading to more stable synaptic and epigenetic aversive memories, more challenging extinction processes, and a diminished capacity to adapt to new experiences. How do these early changes lead to later, rather than more recent, suicide-related outcomes? These preliminary modifications, when considered alongside the physiological and psychosocial burdens that accumulate with age, initiate an allostatic process that gradually alters the set points of various systems, thereby establishing a cumulative manner. The subsequent section elaborates on the constituents of this allostatic load and its quantifiable biomarkers.

From Early Adversity to Allostatic Overload: Progressive Systems Dysregulation

The suprachiasmatic nucleus modulates the basal activity of the HPA axis through circadian rhythms; additionally, activity can be regulated both reactively and anticipatorily (in response to innate or learned expectations) (Herman et al., 2003). This energy-intensive response cannot persist continuously and is adjusted with stress-integrative structures, such as the hippocampus, amygdala, and prefrontal cortex (Herman et al., 2003). Although the serotonergic system’s direct innervation to the paraventricular nucleus is limited, it primarily influences the HPA axis via these stress-integrative structures, particularly involving 5-HT2A and 5-HT1A-mediated processes (Dixon et al., 2025; Herman et al., 2003).
ELAs specifically negatively impact stress-integrative structures, the serotonergic system, and the HPA axis (Malave et al., 2022). These components are vital in the neurobiology of suicide. Their contribution to suicide or later-life psychopathology may be understood through the lens of allostatic load (AL). AL refers to the cumulative biological burden resulting from chronic stress and the accumulation of life stressors over time in the body (Gou et al., 2025). ELAs do not occur in isolation; they additionally serve as indicators of forthcoming challenges, manifesting an ongoing decline (Lacey et al., 2022; Raghunathan et al., 2024). Additionally, early-life pathology tends to have the most significant impact (Raghunathan et al., 2024). Chronic adversities throughout life lead to the gradual deterioration of stress-related systems, eventually causing disruptions in biological rhythms (McEwen, 2017).
Additionally, ongoing adversity alters the HPA axis set point, resulting in impaired stress response to continued adversity. For instance, individuals with ELA history often exhibit lower baseline activity of the HPA axis and show dysregulated cortisol responses to stress (Berardelli et al., 2020). In this context, disruptions in the HPA axis are linked to more memory errors and rigid emotional patterns, which may lead to distorted perceptions and feelings of being a burden (Cicchetti et al., 2010; G. Li et al., 2006; Ness & Calabrese, 2016). Furthermore, the key regulatory role of the serotonergic system in social homeostasis and its impact on the pain system contribute to thwarted belongingness and suicidal capacity (Matthews & Tye, 2019; Neeck, 2000).
Serotonergic median raphe efferents facilitate stress tolerance in the HPA axis through the mesolimbocortical inhibitory system (Lowry, 2002). Changes in serotonin receptor levels may result in dysregulation of the HPA axis (Lowry, 2002). For instance, inflammation and behavioral impairments associated with early life adversity can be mitigated by a reduction in 5-HT1A auto receptors in the hippocampus, with paralleled changes in PVN CRF levels (Dixon et al., 2025). Moreover, the dexamethasone-induced stress response can be normalized through the activation of 5-HT1A receptors by fluoxetine (Nagano et al., 2012).
On the other hand, physical, social, and maternal stress lead to an augmentation in the expression and functionality of 5-HT2A receptors within the frontal cortex (Murnane, 2019). This may represent an adaptive mechanism that enhances sensitivity to threats and facilitates fear learning (Murnane, 2019). Collectively, the alterations in the expression of 5-HT1A and 5-HT2A receptors may offer valuable insights into the pathophysiology of suicide.

5HT1A

Among 45,207 individuals, ELAs (excluding sexual and physical abuse) were associated with a greater risk of fatal suicide attempts (Govender et al., 2025). Additionally, increased 5-HT1A receptor binding in the raphe nucleus was associated with lethal suicidal attempts (Oquendo et al., 2016; Sullivan et al., 2015). However, this connection has not been consistently shown in smaller sample-sized studies(Boldrini et al., 2008; Mann et al., 2019). Furthermore, 5-HT1A binding levels increase following stressful stimuli, particularly in individuals with a history of suicide attempt(Bartlett et al., 2023). These findings suggest that impaired 5-HT1A receptor regulation in individuals exposed to ELA may contribute to the emergence of more deliberate and fatal suicidal behavior. This raises the possibility that some suicides are not merely impulsive but rather a more intentional act resulting from the accumulated stress burden over time.

5HT2A

In vitro postmortem studies have consistently shown that 5-HT2A receptor binding is increased in the prefrontal cortex, and this increase is associated with ELA history and higher aggression scores (Norton & Owen, 2005; Oquendo et al., 2006; Underwood et al., 2018). Conversely, an in vivo study reported decreased 5-HT2A binding in individuals with a history of suicide attempts (Audenaert et al., 2001). However, this decrease may be related to the participants’ long-term antidepressant use (Peroutka & Snyder, 1980). Another small-sample study found no significant difference in 5-HT2A binding between individuals with and without a history of suicide, suggesting that confounding variables such as sample size and antidepressant use may have influenced the results (Mann et al., 2019). The current findings suggest that ELA may act on the 5-HT2A receptor, which is associated with aggression.

Future Directions and Research Priorities

This neuropsychoanalytic model unveils numerous vital opportunities for future research and clinical implementation:

Combined Therapy Protocols

The potential benefits of combining psychedelics with targeted psychotherapies warrant thorough research. Timing therapeutic interventions to coincide with periods of neuroplasticity triggered by psychedelics can enhance treatment effectiveness. For instance, this might involve administering trauma-focused therapy in the days after psychedelic sessions, when neuroplastic changes are at their peak.

Prevention and Early Intervention

The emphasis of the model on developmental timing indicates that interventions implemented during critical periods may prevent the continuation of maladaptive neural patterns. Research ought to explore whether the safe and effective application of psychedelic-assisted therapies for adolescent populations can disrupt the progression from early trauma to adult psychopathology.

Mechanism-Based Management

Future clinical trials ought to advance beyond symptom-based diagnoses and focus on aligning treatments with neurobiological mechanisms. Subjects exhibiting patterns such as serotonin dysfunction, memory generalization, or HPA axis dysregulation may derive significant benefit from interventions specifically targeting these neurobiological signatures.

Long-Term Outcomes and Relapse Prevention

The model suggests that effective interventions may lead to lasting changes in neural architecture that enhance individuals’ resilience to future stressors. Long-term follow-up studies are needed to determine whether psychedelic-assisted therapies result in enduring changes in the biological systems identified by this model.

Ethical Considerations and Safety

The integration of psychedelics into trauma treatment raises important ethical questions, especially considering the vulnerability of individuals who experienced adversity early in life. Trauma-informed care principles must be carefully followed to ensure that psychedelic experiences do not retraumatize or trigger feelings of helplessness.
The model’s focus on internalized object relations makes the therapeutic relationship especially crucial in psychedelic-assisted therapy. Therapists need to be ready to handle transference reactions that psychedelic states can amplify and must strictly maintain safety and boundaries throughout the process.

Conclusion: Toward a Mechanism-Based Psychiatry

This neuropsychoanalytic model represents a fundamental paradigm shift toward mechanistic psychiatry, integrating the psychological and biological aspects of trauma-related pathologies. By identifying specific neural circuits, molecular mechanisms, and developmental processes, it provides a roadmap for developing more effective and targeted interventions for suicide.
The intersection of psychotherapy and psychedelic synaptic plasticity provides opportunities to uniquely target the neurobiological foundations of traumatic memories. These methods are not just about symptom relief but have the potential to change the neural patterns that sustain distress, emotional instability, and suicidal thoughts.
Future advances in this field will require ongoing collaboration among neuroscientists, clinicians, and researchers. The goal is not just to treat mental illnesses; it is to understand how early experiences shape nervous system function and psychological well-being throughout life, and to be able to modify these processes.
The promise of this approach is exciting not only because of its therapeutic potential but also for individuals whose suffering is deeply rooted in biological factors.

References

  1. Abatis, M., Perin, R., Niu, R., van den Burg, E., Hegoburu, C., Kim, R., Okamura, M., Bito, H., Markram, H., & Stoop, R. (2024). Fear learning induces synaptic potentiation between engram neurons in the rat lateral amygdala. Nature Neuroscience, 27(7), 1309–1317. [CrossRef]
  2. Akbar, L., Castillo, V. C. G., Olorocisimo, J. P., Ohta, Y., Kawahara, M., Takehara, H., Haruta, M., Tashiro, H., Sasagawa, K., Ohsawa, M., Akay, Y. M., Akay, M., & Ohta, J. (2023). Multi-Region Microdialysis Imaging Platform Revealed Dorsal Raphe Nucleus Calcium Signaling and Serotonin Dynamics during Nociceptive Pain. International Journal of Molecular Sciences, 24(7), 6654. [CrossRef]
  3. Alcántara-Alonso, V., García-Luna, C., Soberanes-Chávez, P., Estrada-Camarena, E., & de Gortari, P. (2024). Two Adverse Early Life Events Induce Differential Changes in Brain CRH and Serotonin Systems in Rats along with Hyperphagia and Depression. Journal of Integrative Neuroscience, 23(2), 41. [CrossRef]
  4. Angelakis, I., Austin, J. L., & Gooding, P. (2020). Association of Childhood Maltreatment With Suicide Behaviors Among Young People: A Systematic Review and Meta-analysis. JAMA Network Open, 3(8), e2012563. [CrossRef]
  5. Angelakis, I., Gillespie, E. L., & Panagioti, M. (2019). Childhood maltreatment and adult suicidality: A comprehensive systematic review with meta-analysis. Psychological Medicine, 49(7), 1057–1078. [CrossRef]
  6. Audenaert, K., Van Laere, K., Dumont, F., Slegers, G., Mertens, J., van Heeringen, C., & Dierckx, R. A. (2001). Decreased frontal serotonin 5-HT 2a receptor binding index in deliberate self-harm patients. European Journal of Nuclear Medicine, 28(2), 175–182. [CrossRef]
  7. Baltaci, S. B., Mogulkoc, R., & Baltaci, A. K. (2019). Molecular Mechanisms of Early and Late LTP. Neurochemical Research, 44(2), 281–296. [CrossRef]
  8. Baratta, M. V., Kodandaramaiah, S. B., Monahan, P. E., Yao, J., Weber, M. D., Lin, P.-A., Gisabella, B., Petrossian, N., Amat, J., Kim, K., Yang, A., Forest, C. R., Boyden, E. S., & Goosens, K. A. (2016). Stress enables reinforcement-elicited serotonergic consolidation of fear memory. Biological Psychiatry, 79(10), 814–822. [CrossRef]
  9. Bartlett, E. A., Zanderigo, F., Stanley, B., Choo, T.-H., Galfalvy, H. C., Pantazatos, S. P., Sublette, M. E., Miller, J. M., Oquendo, M. A., & Mann, J. J. (2023). In vivo serotonin transporter and 1A receptor binding potential and ecological momentary assessment (EMA) of stress in major depression and suicidal behavior. European Neuropsychopharmacology : The Journal of the European College of Neuropsychopharmacology, 70, 1–13. [CrossRef]
  10. Benekareddy, M., Goodfellow, N. M., Lambe, E. K., & Vaidya, V. A. (2010). Enhanced Function of Prefrontal Serotonin 5-HT2 Receptors in a Rat Model of Psychiatric Vulnerability. The Journal of Neuroscience, 30(36), 12138–12150. [CrossRef]
  11. Benito, E., & Barco, A. (2010). CREB’s control of intrinsic and synaptic plasticity: Implications for CREB-dependent memory models. Trends in Neurosciences, 33(5), 230–240. [CrossRef]
  12. Berardelli, I., Serafini, G., Cortese, N., Fiaschè, F., O’Connor, R. C., & Pompili, M. (2020). The Involvement of Hypothalamus–Pituitary–Adrenal (HPA) Axis in Suicide Risk. Brain Sciences, 10(9), 653. [CrossRef]
  13. Berg, B. A., Schoenbaum, G., & McDannald, M. A. (2014). The dorsal raphe nucleus is integral to negative prediction errors in Pavlovian fear. The European Journal of Neuroscience, 40(7), 3096–3101. [CrossRef]
  14. Boldrini, M., Underwood, M. D., Mann, J. J., & Arango, V. (2008). Serotonin-1A autoreceptor binding in the dorsal raphe nucleus of depressed suicides. Journal of Psychiatric Research, 42(6), 433–442. [CrossRef]
  15. Boscaglia, M., Gastaldi, C., Gerstner, W., & Quian Quiroga, R. (2023). A dynamic attractor network model of memory formation, reinforcement and forgetting. PLoS Computational Biology, 19(12), e1011727. [CrossRef]
  16. Bourgognon, J.-M., & Cavanagh, J. (2020). The role of cytokines in modulating learning and memory and brain plasticity. Brain and Neuroscience Advances, 4, 2398212820979802. [CrossRef]
  17. Bowlby, J. (1951). Maternal care and mental health. World Health Organization Monograph Series, 2, 179–179.
  18. Bowlby, J. (1979). The making and breaking of affectional bonds. Tavistock Publ.
  19. Brosens, N., Lesuis, S. L., Rao-Ruiz, P., van den Oever, M. C., & Krugers, H. J. (2024). Shaping Memories via Stress: A Synaptic Engram Perspective. Biological Psychiatry, 95(8), 721–731. [CrossRef]
  20. Buecker, S., Doll, J., Abrantes Diaz, S., Haehner, P., Berg, F., Kaurin, A., & Teismann, T. (2025). Self-Esteem and Suicidal Thoughts and Behaviors: A Meta-Analytic Review. Clinical Psychological Science, 21677026241308163. [CrossRef]
  21. Choi, J.-H., Sim, S.-E., Kim, J.-I., Choi, D. I., Oh, J., Ye, S., Lee, J., Kim, T., Ko, H.-G., Lim, C.-S., & Kaang, B.-K. (2018). Interregional synaptic maps among engram cells underlie memory formation. Science (New York, N.Y.), 360(6387), 430–435. [CrossRef]
  22. Cicchetti, D., Rogosch, F. A., Howe, M. L., & Toth, S. L. (2010). The effects of maltreatment and neuroendocrine regulation on memory performance. Child Development, 81(5), 1504–1519. [CrossRef]
  23. Cullen, K. R., Vizueta, N., Thomas, K. M., Han, G. J., Lim, K. O., Camchong, J., Mueller, B. A., Bell, C. H., Heller, M. D., & Schulz, S. C. (2011). Amygdala Functional Connectivity in Young Women with Borderline Personality Disorder. Brain Connectivity, 1(1), 61–71. [CrossRef]
  24. de Souza, J. A., da Silva, M. C., Costa, F. C. O., de Matos, R. J. B., de Farias Campina, R. C., do Amaral Almeida, L. C., da Silva, A. A. M., Cavalcante, T. C. F., Tavares, G. A., & de Souza, S. L. (2020). Early life stress induced by maternal separation during lactation alters the eating behavior and serotonin system in middle-aged rat female offspring. Pharmacology, Biochemistry, and Behavior, 192, 172908. [CrossRef]
  25. Dittmer, P. J., Dell’Acqua, M. L., & Sather, W. A. (2019). Synaptic crosstalk conferred by a zone of differentially regulated Ca2+ signaling in the dendritic shaft adjoining a potentiated spine. Proceedings of the National Academy of Sciences of the United States of America, 116(27), 13611–13620. [CrossRef]
  26. Dixon, R., Malave, L., Thompson, R., Wu, S., Li, Y., Sadik, N., & Anacker, C. (2025). Sex-specific and developmental effects of early life adversity on stress reactivity are rescued by postnatal knockdown of 5-HT1A autoreceptors. Neuropsychopharmacology, 50(3), 507–518. [CrossRef]
  27. Dube, S. R., Anda, R. F., Felitti, V. J., Chapman, D. P., Williamson, D. F., & Giles, W. H. (2001). Childhood abuse, household dysfunction, and the risk of attempted suicide throughout the life span: Findings from the Adverse Childhood Experiences Study. JAMA, 286(24), 3089–3096. [CrossRef]
  28. Etkin, A., Egner, T., & Kalisch, R. (2011). Emotional processing in anterior cingulate and medial prefrontal cortex. Trends in Cognitive Sciences, 15(2), 85–93. [CrossRef]
  29. Francis, D., Diorio, J., Liu, D., & Meaney, M. J. (1999). Nongenomic transmission across generations of maternal behavior and stress responses in the rat. Science (New York, N.Y.), 286(5442), 1155–1158. [CrossRef]
  30. Gardner, K. L., Hale, M. W., Lightman, S. L., Plotsky, P. M., & Lowry, C. A. (2009). Adverse early life experience and social stress during adulthood interact to increase serotonin transporter mRNA expression. Brain Research, 1305, 47–63. [CrossRef]
  31. Gay, M. (2025). Enhancing Person-Centred Care in Suicide Prevention: A Nursing Perspective. Journal of Psychiatric and Mental Health Nursing, 32(4), 891–896. [CrossRef]
  32. Gereau, R. W., & Conn, P. J. (1994). Presynaptic enhancement of excitatory synaptic transmission by beta-adrenergic receptor activation. Journal of Neurophysiology, 72(3), 1438–1442. [CrossRef]
  33. Gou, Y., Cheng, S., Kang, M., Zhou, R., Liu, C., Hui, J., Liu, Y., Wang, B., Shi, P., & Zhang, F. (2025). Association of Allostatic Load With Depression, Anxiety, and Suicide: A Prospective Cohort Study. Biological Psychiatry, 97(8), 786–793. [CrossRef]
  34. Govender, T., Vidal-Ribas, P., Yu, J., Haynie, D. L., Augustin, D., & Gilman, S. E. (2025). Adverse childhood experiences and risk of suicide and substance-related mortality through middle adulthood. Journal of Affective Disorders, 369, 1201–1208. [CrossRef]
  35. Gundersen, S. (2022). Psychoanalysis and Neuropsychological Explanations. Psychoanalytic Review, 109(4), 415–437. [CrossRef]
  36. Guskjolen, A., Kenney, J. W., de la Parra, J., Yeung, B.-R. A., Josselyn, S. A., & Frankland, P. W. (2018). Recovery of “Lost” Infant Memories in Mice. Current Biology : CB, 28(14), 2283-2290.e3. [CrossRef]
  37. Halder, R., Hennion, M., Vidal, R. O., Shomroni, O., Rahman, R.-U., Rajput, A., Centeno, T. P., van Bebber, F., Capece, V., Vizcaino, J. C. G., Schuetz, A.-L., Burkhardt, S., Benito, E., Sala, M. N., Javan, S. B., Haass, C., Schmid, B., Fischer, A., & Bonn, S. (2016). DNA methylation changes in plasticity genes accompany the formation and maintenance of memory. Nature Neuroscience, 19(1), 102–110. [CrossRef]
  38. Hall, J. E., & Guyton, A. C. (2016). Guyton and Hall textbook of medical physiology (13th edition). Elsevier.
  39. Hall, N. T., & Hallquist, M. N. (2023). Dissociation of basolateral and central amygdala effective connectivity predicts the stability of emotion-related impulsivity in adolescents and emerging adults with borderline personality symptoms: A resting-state fMRI study. Psychological Medicine, 53(8), 3533–3547. [CrossRef]
  40. Hanson, B., Stall, S., Cutcher-Gershenfeld, J., Vrouwenvelder, K., Wirz, C., Rao, Y. D., & Peng, G. (2023). Garbage in, garbage out: Mitigating risks and maximizing benefits of AI in research. Nature, 623(7985), 28–31. [CrossRef]
  41. Herman, J. P., Figueiredo, H., Mueller, N. K., Ulrich-Lai, Y., Ostrander, M. M., Choi, D. C., & Cullinan, W. E. (2003). Central mechanisms of stress integration: Hierarchical circuitry controlling hypothalamo-pituitary-adrenocortical responsiveness. Frontiers in Neuroendocrinology, 24(3), 151–180. [CrossRef]
  42. Högberg, G., Nardo, D., Hällström, T., & Pagani, M. (2011). Affective psychotherapy in post-traumatic reactions guided by affective neuroscience: Memory reconsolidation and play. Psychology Research and Behavior Management, 4, 87–96. [CrossRef]
  43. Howard, C. E., Chen, C.-L., Tabachnik, T., Hormigo, R., Ramdya, P., & Mann, R. S. (2019). Serotonergic modulation of walking in Drosophila. Current Biology : CB, 29(24), 4218-4230.e8. [CrossRef]
  44. Izquierdo, I., & Medina, J. H. (1997). Memory formation: The sequence of biochemical events in the hippocampus and its connection to activity in other brain structures. Neurobiology of Learning and Memory, 68(3), 285–316. [CrossRef]
  45. Jiang, X., Naik, M. U., Hrabe, J., & Sacktor, T. C. (1994). Developmental expression of the protein kinase C family in rat hippocampus. Brain Research. Developmental Brain Research, 78(2), 291–295. [CrossRef]
  46. Josselyn, S. A., & Tonegawa, S. (2020). Memory engrams: Recalling the past and imagining the future. Science (New York, N.Y.), 367(6473), eaaw4325. [CrossRef]
  47. Karen, C., & Rajan, K. E. (2019). Social Behaviour and Epigenetic Status in Adolescent and Adult Rats: The Contribution of Early-Life Stressful Social Experience. Cellular and Molecular Neurobiology, 39(3), 371–385. [CrossRef]
  48. Karst, H., Berger, S., Turiault, M., Tronche, F., Schütz, G., & Joëls, M. (2005). Mineralocorticoid receptors are indispensable for nongenomic modulation of hippocampal glutamate transmission by corticosterone. Proceedings of the National Academy of Sciences of the United States of America, 102(52), 19204–19207. [CrossRef]
  49. Kernberg, O. (1967). Borderline personality organization. Journal of the American Psychoanalytic Association, 15(3), 641–685. [CrossRef]
  50. Kernberg, O. F. (1976). Object-relations theory and clinical psychoanalysis. J. Aronson.
  51. Kimura, S., Togashi, H., Matsumoto, M., Shiozawa, T., Ishida, J., Kano, S., Ohashi, A., Ishikawa, S., Yamaguchi, T., Yoshioka, M., & Shimamura, K. (2011). Serotonin(1A) receptor-mediated synaptic response in the rat medial prefrontal cortex is altered by early life stress: In vivo and in vitro electrophysiological studies. Nihon Shinkei Seishin Yakurigaku Zasshi = Japanese Journal of Psychopharmacology, 31(1), 9–15.
  52. Kitamura, T., Ogawa, S. K., Roy, D. S., Okuyama, T., Morrissey, M. D., Smith, L. M., Redondo, R. L., & Tonegawa, S. (2017). Engrams and circuits crucial for systems consolidation of a memory. Science, 356(6333), 73–78. [CrossRef]
  53. Klein, M. (1984). Envy and gratitude, and other works, 1946-1963 (Free Press ed). Free Press.
  54. Kuhlman, K. R., Chiang, J. J., Horn, S., & Bower, J. E. (2017). Developmental psychoneuroendocrine and psychoneuroimmune pathways from childhood adversity to disease. Neuroscience and Biobehavioral Reviews, 80, 166–184. [CrossRef]
  55. Kumar, V., Abbas, A. K., Aster, J. C., Perkins, J. A., Robbins, S. L., & Cotran, R. S. (2015). Robbins and Cotran pathologic basis of disease (Ninth edition). Elsevier; Saunders.
  56. Kuyken, W., & Brewin, C. R. (1995). Autobiographical memory functioning in depression and reports of early abuse. Journal of Abnormal Psychology, 104(4), 585–591. [CrossRef]
  57. Lacey, R. E., Howe, L. D., Kelly-Irving, M., Bartley, M., & Kelly, Y. (2022). The Clustering of Adverse Childhood Experiences in the Avon Longitudinal Study of Parents and Children: Are Gender and Poverty Important? Journal of Interpersonal Violence, 37(5–6), 2218–2241. [CrossRef]
  58. Lapate, R. C., Samaha, J., Rokers, B., Hamzah, H., Postle, B. R., & Davidson, R. J. (2017). Inhibition of Lateral Prefrontal Cortex Produces Emotionally Biased First Impressions: A Transcranial Magnetic Stimulation and Electroencephalography Study. Psychological Science, 28(7), 942–953. [CrossRef]
  59. Larsen, M. E., Buonarati, O. R., Qian, H., Hell, J. W., & Bayer, K. U. (2023). Stimulating β-adrenergic receptors promotes synaptic potentiation by switching CaMKII movement from LTD to LTP mode. The Journal of Biological Chemistry, 299(6), 104706. [CrossRef]
  60. Lee, C. R., Chen, A., & Tye, K. M. (2021). The neural circuitry of social homeostasis: Consequences of acute versus chronic social isolation. Cell, 184(6), 1500–1516. [CrossRef]
  61. Lesuis, S. L., Brosens, N., Immerzeel, N., van der Loo, R. J., Mitrić, M., Bielefeld, P., Fitzsimons, C. P., Lucassen, P. J., Kushner, S. A., van den Oever, M. C., & Krugers, H. J. (2021). Glucocorticoids Promote Fear Generalization by Increasing the Size of a Dentate Gyrus Engram Cell Population. Biological Psychiatry, 90(7), 494–504. [CrossRef]
  62. Lesuis, S. L., Park, S., Hoorn, A., Rashid, A. J., Mocle, A. J., Salter, E. W., Vislavski, S., Gray, M. T., Torelli, A. M., DeCristofaro, A., Driever, W. P. F., van der Stelt, M., Zweifel, L. S., Collingridge, G. L., Lefebvre, J. L., Walters, B. J., Frankland, P. W., Hill, M. N., & Josselyn, S. A. (2025). Stress disrupts engram ensembles in lateral amygdala to generalize threat memory in mice. Cell, 188(1), 121-140.e20. [CrossRef]
  63. Li, G., Cherrier, M. M., Tsuang, D. W., Petrie, E. C., Colasurdo, E. A., Craft, S., Schellenberg, G. D., Peskind, E. R., Raskind, M. A., & Wilkinson, C. W. (2006). Salivary cortisol and memory function in human aging. Neurobiology of Aging, 27(11), 1705–1714. [CrossRef]
  64. Li, H., Liu, K., Fei, J., Yuan, T., & Mei, S. (2024). Association of early parent–child separation with depression, social and academic performance in adolescence and early adulthood: A prospective cohort study. Child and Adolescent Psychiatry and Mental Health, 18, 78. [CrossRef]
  65. Lowry, C. A. (2002). Functional subsets of serotonergic neurones: Implications for control of the hypothalamic-pituitary-adrenal axis. Journal of Neuroendocrinology, 14(11), 911–923. [CrossRef]
  66. Main, M., Kaplan, N., & Cassidy, J. (1985). Security in infancy, childhood, and adulthood: A move to the level of representation. Monographs of the Society for Research in Child Development, 50(1–2), 66–104. [CrossRef]
  67. Malave, L., van Dijk, M. T., & Anacker, C. (2022). Early life adversity shapes neural circuit function during sensitive postnatal developmental periods. Translational Psychiatry, 12(1), 1–14. [CrossRef]
  68. Mann, J. J., Metts, A. V., Ogden, R. T., Mathis, C. A., Rubin-Falcone, H., Gong, Z., Drevets, W. C., Zelazny, J., & Brent, D. A. (2019). Quantification of 5-HT1A and 5-HT2A receptor Binding in Depressed Suicide Attempters and Non-Attempters. Archives of Suicide Research: Official Journal of the International Academy for Suicide Research, 23(1), 122–133. [CrossRef]
  69. Matthews, G. A., & Tye, K. M. (2019). Neural mechanisms of social homeostasis. Annals of the New York Academy of Sciences, 1457(1), 5–25. [CrossRef]
  70. McEwen, B. S. (2017). Neurobiological and Systemic Effects of Chronic Stress. Chronic Stress, 1, 2470547017692328. [CrossRef]
  71. Melamed, D. M., Botting, J., Lofthouse, K., Pass, L., & Meiser-Stedman, R. (2024). The Relationship Between Negative Self-Concept, Trauma, and Maltreatment in Children and Adolescents: A Meta-Analysis. Clinical Child and Family Psychology Review, 27(1), 220–234. [CrossRef]
  72. Murnane, K. S. (2019). Serotonin 2A Receptors are a Stress Response System: Implications for Post-Traumatic Stress Disorder. Behavioural Pharmacology, 30(2-), 151–162. [CrossRef]
  73. Nagano, M., Liu, M., Inagaki, H., Kawada, T., & Suzuki, H. (2012). Early intervention with fluoxetine reverses abnormalities in the serotonergic system and behavior of rats exposed prenatally to dexamethasone. Neuropharmacology, 63(2), 292–300. [CrossRef]
  74. Nakamura, K., Kosugi, I., Lee, D. Y., Hafner, A., Sinclair, D. A., Ryo, A., & Lu, K. P. (2012). Prolyl isomerase Pin1 regulates neuronal differentiation via β-catenin. Molecular and Cellular Biology, 32(15), 2966–2978. [CrossRef]
  75. Neeck, G. (2000). Neuroendocrine and hormonal perturbations and relations to the serotonergic system in fibromyalgia patients. Scandinavian Journal of Rheumatology. Supplement, 113, 8–12.
  76. Ness, D., & Calabrese, P. (2016). Stress Effects on Multiple Memory System Interactions. Neural Plasticity, 2016, 4932128. [CrossRef]
  77. Newcombe, N., & Fox, N. A. (1994). Infantile amnesia: Through a glass darkly. Child Development, 65(1), 31–40.
  78. Norton, N., & Owen, M. J. (2005). HTR2A: Association and expression studies in neuropsychiatric genetics. Annals of Medicine, 37(2), 121–129. [CrossRef]
  79. O’Connor, R. C., & Kirtley, O. J. (2018). The integrated motivational–volitional model of suicidal behaviour. Philosophical Transactions of the Royal Society B: Biological Sciences, 373(1754), 20170268. [CrossRef]
  80. O’Dell, T. J., Connor, S. A., Guglietta, R., & Nguyen, P. V. (2015). β-Adrenergic receptor signaling and modulation of long-term potentiation in the mammalian hippocampus. Learning & Memory (Cold Spring Harbor, N.Y.), 22(9), 461–471. [CrossRef]
  81. Oliogu, E., & Ruocco, A. C. (2024). DSM-5 suicidal behavior disorder: A systematic review of research on clinical utility, diagnostic boundaries, measures, pathophysiology and interventions. Frontiers in Psychiatry, 15, 1278230. [CrossRef]
  82. Opendak, M., Zanca, R. M., Anane, E., Serrano, P. A., & Sullivan, R. M. (2018). Developmental transitions in amygdala PKC isoforms and AMPA receptor expression associated with threat memory in infant rats. Scientific Reports, 8, 14679. [CrossRef]
  83. Oquendo, M. A., Galfalvy, H., Sullivan, G. M., Miller, J. M., Milak, M. M., Sublette, M. E., Cisneros-Trujillo, S., Burke, A. K., Parsey, R. V., & Mann, J. J. (2016). Positron Emission Tomographic Imaging of the Serotonergic System and Prediction of Risk and Lethality of Future Suicidal Behavior. JAMA Psychiatry, 73(10), 1048–1055. [CrossRef]
  84. Oquendo, M. A., Russo, S. A., Underwood, M. D., Kassir, S. A., Ellis, S. P., Mann, J. J., & Arango, V. (2006). Higher postmortem prefrontal 5-HT2A receptor binding correlates with lifetime aggression in suicide. Biological Psychiatry, 59(3), 235–243. [CrossRef]
  85. Peroutka, S. J., & Snyder, S. H. (1980). Long-term antidepressant treatment decreases spiroperidol-labeled serotonin receptor binding. Science (New York, N.Y.), 210(4465), 88–90. [CrossRef]
  86. Pfrieger, F. W. (2003). Role of cholesterol in synapse formation and function. Biochimica Et Biophysica Acta, 1610(2), 271–280. [CrossRef]
  87. Pittaluga, A., & Raiteri, M. (1992). N-methyl-D-aspartic acid (NMDA) and non-NMDA receptors regulating hippocampal norepinephrine release. I. Location on axon terminals and pharmacological characterization. The Journal of Pharmacology and Experimental Therapeutics, 260(1), 232–237.
  88. Pouget, C., & Vetere, G. (2023). Fear memory engram is the mind-killer. Nature Neuroscience, 26(5), 729–731. [CrossRef]
  89. Raghunathan, R. S., Johnson, S. B., Voegtline, K. M., Sosnowski, D. W., Kuehn, M., Ialongo, N., & Musci, R. J. (2024). Longitudinal Patterns of Adversity from Childhood to Adolescence: Examining Associations with Mental Health through Emerging Adulthood using a Random-Intercept Latent Transition Analysis. Developmental Psychology, 60(5), 840–857. [CrossRef]
  90. Roberson, E. D., English, J. D., Adams, J. P., Selcher, J. C., Kondratick, C., & Sweatt, J. D. (1999). The mitogen-activated protein kinase cascade couples PKA and PKC to cAMP response element binding protein phosphorylation in area CA1 of hippocampus. The Journal of Neuroscience: The Official Journal of the Society for Neuroscience, 19(11), 4337–4348. [CrossRef]
  91. Schanzenbächer, C. T., Langer, J. D., & Schuman, E. M. (2018). Time- and polarity-dependent proteomic changes associated with homeostatic scaling at central synapses. eLife, 7, e33322. [CrossRef]
  92. Scholl, J., Kolling, N., Nelissen, N., Browning, M., Rushworth, M. F. S., & Harmer, C. J. (2017). Beyond negative valence: 2-week administration of a serotonergic antidepressant enhances both reward and effort learning signals. PLoS Biology, 15(2), e2000756. [CrossRef]
  93. Sengupta, A., & Holmes, A. (2019). A discrete dorsal raphe to basal amygdala 5-HT circuit calibrates aversive memory. Neuron, 103(3), 489-505.e7. [CrossRef]
  94. Solms, M., & Turnbull, O. (2018). The brain and the inner world: An introduction to the neuroscience of subjective experience. Routledge.
  95. Sood, A., Pati, S., Bhattacharya, A., Chaudhari, K., & Vaidya, V. A. (2018). Early emergence of altered 5-HT2A receptor-evoked behavior, neural activation and gene expression following maternal separation. International Journal of Developmental Neuroscience: The Official Journal of the International Society for Developmental Neuroscience, 65, 21–28. [CrossRef]
  96. Sullivan, G. M., Oquendo, M. A., Milak, M., Miller, J. M., Burke, A., Ogden, R. T., Parsey, R. V., & Mann, J. J. (2015). Positron Emission Tomography Quantification of Serotonin1A Receptor Binding in Suicide Attempters With Major Depressive Disorder. JAMA Psychiatry, 72(2), 169–178. [CrossRef]
  97. Svrakic, D. M., & Zorumski, C. F. (2021). Neuroscience of Object Relations in Health and Disorder: A Proposal for an Integrative Model. Frontiers in Psychology, 12, 583743. [CrossRef]
  98. Tau, G. Z., & Peterson, B. S. (2010). Normal Development of Brain Circuits. Neuropsychopharmacology, 35(1), 147–168. [CrossRef]
  99. Tortora, F., Hadipour, A. L., Battaglia, S., Falzone, A., Avenanti, A., & Vicario, C. M. (2023a). The Role of Serotonin in Fear Learning and Memory: A Systematic Review of Human Studies. Brain Sciences, 13(8), 1197. [CrossRef]
  100. Tortora, F., Hadipour, A. L., Battaglia, S., Falzone, A., Avenanti, A., & Vicario, C. M. (2023b). The Role of Serotonin in Fear Learning and Memory: A Systematic Review of Human Studies. Brain Sciences, 13(8), 1197. [CrossRef]
  101. Underwood, M. D., Kassir, S. A., Bakalian, M. J., Galfalvy, H., Dwork, A. J., Mann, J. J., & Arango, V. (2018). Serotonin receptors and suicide, major depression, alcohol use disorder and reported early life adversity. Translational Psychiatry, 8(1), 279. [CrossRef]
  102. Urb, M., Anier, K., Matsalu, T., Aonurm-Helm, A., Tasa, G., Koppel, I., Zharkovsky, A., Timmusk, T., & Kalda, A. (2019). Glucocorticoid Receptor Stimulation Resulting from Early Life Stress Affects Expression of DNA Methyltransferases in Rat Prefrontal Cortex. Journal of Molecular Neuroscience: MN, 68(1), 99–110. [CrossRef]
  103. van Bodegom, M., Homberg, J. R., & Henckens, M. J. A. G. (2017). Modulation of the Hypothalamic-Pituitary-Adrenal Axis by Early Life Stress Exposure. Frontiers in Cellular Neuroscience, 11, 87. [CrossRef]
  104. Van Orden, K. A., Witte, T. K., Cukrowicz, K. C., Braithwaite, S., Selby, E. A., & Joiner, T. E. (2010). The Interpersonal Theory of Suicide. Psychological Review, 117(2), 575–600. [CrossRef]
  105. Wang, C.-C., & Wang, S.-J. (2009). Modulation of presynaptic glucocorticoid receptors on glutamate release from rat hippocampal nerve terminals. Synapse (New York, N.Y.), 63(9), 745–751. [CrossRef]
  106. Wang, X., Jiang, L., Ma, W., Zheng, X., He, E., Zhang, B., Vashisth, M. K., & Gong, Z. (2022). Maternal separation affects anxiety-like behavior beginning in adolescence and continuing through adulthood and related to Dnmt3a expression. Journal of Neurophysiology, 128(3), 611–618. [CrossRef]
  107. Williams, J. M., & Broadbent, K. (1986). Autobiographical memory in suicide attempters. Journal of Abnormal Psychology, 95(2), 144–149. [CrossRef]
  108. Williams, J. M. G., Barnhofer, T., Crane, C., Hermans, D., Raes, F., Watkins, E., & Dalgleish, T. (2007). Autobiographical Memory Specificity and Emotional Disorder. Psychological Bulletin, 133(1), 122–148. [CrossRef]
  109. Wisłowska-Stanek, A., Kołosowska, K., & Maciejak, P. (2021). Neurobiological Basis of Increased Risk for Suicidal Behaviour. Cells, 10(10), 2519. [CrossRef]
  110. World Health Organization. (2025, March 25). Suicide. World Health Organization. https://www.who.int/news-room/fact-sheets/detail/suicide.
  111. Wu, X., Morishita, W., Beier, K. T., Heifets, B. D., & Malenka, R. C. (2021). 5-HT modulation of a medial septal circuit tunes social memory stability. Nature, 599(7883), 96–101. [CrossRef]
  112. Yang, T., Nie, Z., Shu, H., Kuang, Y., Chen, X., Cheng, J., Yu, S., & Liu, H. (2020). The Role of BDNF on Neural Plasticity in Depression. Frontiers in Cellular Neuroscience, 14, 82. [CrossRef]
  113. Zhang, X., Kim, J., & Tonegawa, S. (2020). Amygdala Reward Neurons Form and Store Fear Extinction Memory. Neuron, 105(6), 1077-1093.e7. [CrossRef]
  114. Zhaoyang, R., Harrington, K. D., Scott, S. B., Graham-Engeland, J. E., & Sliwinski, M. J. (2022). Daily Social Interactions and Momentary Loneliness: The Role of Trait Loneliness and Neuroticism. The Journals of Gerontology Series B: Psychological Sciences and Social Sciences, 77(10), 1791–1802. [CrossRef]
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