New ‘Pendular’ Model Casts Mental Health as a Swing Between Rigidity and Chaos

A new theoretical paper proposes that mental health and mental illness can be understood through a single structural framework grounded in the mathematics of complex systems: the pendulum. In a conceptual analysis published in Frontiers in Psychology, Andres F. Mambuca of the Mental Health Institute of Florida introduces the Pendular Regulation Model, or PRM, a transdiagnostic framework that portrays psychological functioning as bounded oscillatory regulation within hierarchical predictive systems embedded in stress-responsive neurovisceral networks. Rather than treating diagnoses as discrete disease entities, the model suggests that psychiatric symptoms may reflect two broad kinds of maladaptive stabilization — regulatory constriction, in which the system swings too little, and regulatory destabilization, in which it swings too much.

The paper arrives amid persistent concerns about psychiatric classification. Although diagnostic reliability has improved substantially over recent decades, researchers continue to flag problems of construct validity, diagnostic heterogeneity, and excessive comorbidity. Individuals who meet criteria for the same categorical diagnosis frequently show divergent symptom profiles, illness trajectories, and treatment responses. That variability challenges the assumption that each diagnosis corresponds to a single underlying disease mechanism. In response, the field has produced several influential alternatives: the Hierarchical Taxonomy of Psychopathology reorganizes phenomena into empirically derived spectra, the Research Domain Criteria grounds psychopathology in neurobehavioral systems that cut across categories, network approaches describe disorders as interacting symptom systems, and process-based therapy emphasizes modifiable mechanisms spanning diagnostic boundaries.

Mambuca argues that these frameworks, while significant, each emphasize one piece of the puzzle — structural covariance, neurofunctional systems, symptom dynamics, or therapeutic mechanisms — without fully articulating a unified regulatory architecture. PRM’s ambition is to integrate nonlinear system dynamics, hierarchical predictive inference, stress physiology, and long-term identity consolidation within one explanatory scaffold. Psychological functioning, in this view, unfolds across multiple interacting timescales: emotional states fluctuate over minutes or hours, cognitive priors update across contexts, and identity consolidates across developmental epochs. The model takes its name from the claim that healthy regulation resembles a pendulum’s bounded swing — patterned fluctuation contained within integrative thresholds — rather than either a frozen needle or a wildly whipping arc. Crucially, the author adopts this dynamical language not as metaphor alone but as a structural framework intended for modeling regulatory behavior across levels of organization.

The mathematical backbone of the model comes from nonlinear dynamical systems theory. Complex adaptive systems exhibit nonlinear feedback, multistability, and emergent organization, meaning identical inputs can produce divergent outputs depending on system history, internal configuration, and parameter thresholds. Within this language, attractor states are relatively stable configurations toward which a system converges, and attractor basins vary in depth, width, and permeability. Deep basins resist perturbation; shallow basins permit frequent transitions. In PRM, adaptive functioning corresponds to preserved oscillatory variability within these basins, while pathology takes two distinct geometric forms. Regulatory constriction corresponds to excessively deep and narrow basins — systems that resist updating even when environmental contingencies change, exemplified by hyper-stable rumination, persistent threat anticipation, compulsive avoidance, and entrenched self-beliefs. Regulatory destabilization corresponds to shallow or poorly defined basins lacking containment, where minor perturbations produce disproportionate shifts, as seen in emotional volatility, rapid state-switching, and fragmented self-coherence.

Importantly, the model distinguishes emotional intensity from regulatory instability. High arousal may remain adaptive when integrated within bounded geometry, while even low-intensity fluctuation can become destabilizing when hierarchical containment fails. This distinction aligns with empirical findings that both emotional suppression and affective volatility predict dysfunction. The framework also incorporates phase-transition phenomena: gradual accumulation of stressors may precipitate abrupt reorganization once thresholds are exceeded, matching clinical reports of sudden symptom escalation after prolonged subclinical strain. Multistability adds explanatory depth, accounting for why similar stress exposure produces heterogeneous outcomes — rather than invoking latent disease entities, PRM conceptualizes symptom expression as stabilization within particular regulatory geometries. The author stresses that these geometries are not intended to map one-to-one onto diagnostic categories: clinically similar symptoms may differ in temporal dynamics, recovery patterns, and physiological correlates, and distinguishing regulatory geometry from symptom intensity alone would require longitudinal assessment.

The second pillar of the model is predictive processing, which conceptualizes the brain as a hierarchical generative model that minimizes prediction error through recursive updating. At each level, predictions descend while prediction errors ascend, and crucially, those errors are weighted by precision — the estimated reliability of incoming signals. Precision calibration, in this account, determines system flexibility. Excessively precise priors inhibit updating and produce rigidity, whereas insufficient precision produces volatility and overcorrection. Within PRM, constriction may correspond to hyper-precise high-level priors that override corrective sensory input — persistent threat expectancy in anxiety being a candidate example — while destabilization may reflect unstable precision weighting that lets lower-level signals drive excessive updating. Prefrontal–limbic integration plays a central role in this calibration, with the prefrontal cortex supporting contextual inference and inhibitory modulation while limbic structures encode salience and affective intensity. The author is explicit that precision parameters cannot yet be measured directly in clinical settings; behavioral and psychometric proxies such as updating flexibility, intolerance of uncertainty, and recovery velocity may instead indirectly index the underlying hierarchical calibration.

The third pillar grounds regulatory geometry in the body. The neurovisceral integration model holds that adaptive emotional regulation depends on functional integration between prefrontal cortical systems and autonomic output, with vagal tone — often indexed by heart rate variability — reflecting regulatory capacity and inhibitory control. Reduced heart rate variability has been associated with anxiety, depression, and impaired flexibility, and PRM conceptualizes it as a peripheral correlate of oscillatory tolerance. Allostatic load research reinforces this picture: chronic stress exposure reshapes neural architecture through glucocorticoid-mediated modulation of prefrontal and hippocampal systems, potentially impairing top-down regulation and narrowing regulatory range. The model differentiates adaptive recalibration from maladaptive narrowing — defensive stabilization may be protective in genuinely dangerous contexts, but pathology emerges when environmental contingencies shift while regulatory geometry remains rigidly stabilized or chronically destabilized.

Perhaps the most provocative extension concerns identity. Contemporary scholarship increasingly treats identity as neither a static essence nor a purely narrative artifact but an emergent property of distributed neural and psychological processes. PRM proposes that identity coherence is the long-term stabilization of repeated regulatory trajectories: high-level priors embedded in hierarchical generative models organize perception, memory, affective interpretation, and expectation, and recurrent oscillatory patterns consolidate over time into stable expectations about the self and the world. Early attachment disruptions, chronic unpredictability, or persistent threat exposure may deepen defensive attractor basins that gradually consolidate into identity-level beliefs such as feeling fundamentally unsafe or viewing others as unreliable. The model outlines three identity-related geometries — rigid stabilization, fragmented stabilization, and adaptive plasticity — with the adaptive form reflecting high-level priors that remain stable yet permeable, allowing updating without loss of coherence. The framework avoids metaphysical claims about where identity is located, instead pointing toward distributed integration across prefrontal, limbic, and interoceptive networks.

The paper also positions PRM against neighboring constructs. Emotion regulation research has identified strategies such as cognitive reappraisal and suppression as central to adaptive functioning; PRM situates them within regulatory geometry, proposing that reappraisal may reshape basin depth by altering high-level priors while suppression may temporarily dampen oscillatory amplitude without modifying basin structure. Psychological flexibility is a well-supported transdiagnostic mechanism, but PRM seeks to model the structural constraints within which flexibility operates — two individuals may show similar flexibility scores yet differ in basin geometry. Network theory, meanwhile, conceptualizes psychopathology as self-reinforcing symptom systems, and PRM aims to complement it by modeling the regulatory landscape in which such networks stabilize. Recognizing that conceptual integration alone does not justify theoretical contribution, the paper lays out a staged empirical program. A psychometric stage would develop indices of oscillatory tolerance, updating flexibility, and recovery velocity and test whether they add predictive validity beyond established measures of psychological flexibility and emotion regulation. A longitudinal stage would use ecological momentary assessment and intensive longitudinal designs to estimate within-person regulatory range, recovery dynamics, and state transitions. A physiological stage would examine heart rate variability recovery profiles, interoceptive indices, and markers of cumulative stress burden as correlates of regulatory geometry. An interventional stage would test whether interventions targeting attentional and regulatory control alter regulatory range and recovery velocity, and whether such changes mediate clinical outcomes.

The paper is candid about its status and its risks. The author specifies explicit falsifiability criteria: the model would be undermined if its regulatory indices are fully subsumed by psychological flexibility measures, if oscillatory tolerance fails to predict longitudinal recovery trajectories, if physiological indices show no systematic association, or if mediation analyses fail to demonstrate mechanistic contribution. PRM remains a conceptual model pending operationalization; its overlap with flexibility and regulation constructs must be empirically evaluated; its neurocomputational embedding is inferential rather than directly measurable; cultural and developmental generalizability require validation; and physiological correlations are partial proxies rather than direct measures of geometry. The model is positioned as integrative rather than adversarial — not a new diagnostic taxonomy or a replacement for existing frameworks, but a potential structural scaffold for organizing cross-diagnostic variability and treatment research. Its value, as the author emphasizes, will depend not on theoretical scope but on whether its constructs can be measured, its predictions tested, and its falsifiability criteria met. If supported, it may offer a unifying language for why some minds swing too stiffly and others too freely; if unsupported, its limitations will help clarify the boundaries of dynamical and predictive approaches to psychopathology.

Subject of Research: A proposed transdiagnostic model describing emotional regulation as bounded oscillation between regulatory constriction and destabilization

Article Title: The pendular regulation model: a transdiagnostic approach to emotional regulation

Article References: Mambuca, A. F. (2026). The pendular regulation model: a transdiagnostic approach to emotional regulation. Frontiers in Psychology, 17, Article 1813038. https://doi.org/10.3389/fpsyg.2026.1813038

Image Credits: AI Generated

DOI: 10.3389/fpsyg.2026.1813038

Keywords: transdiagnostic, emotion regulation, predictive processing, nonlinear dynamics, psychopathology, heart rate variability, allostatic load, identity coherence, psychological flexibility, HiTOP, RDoC, network models