Icosa and Diagnosis: The Geometry Under the Label

Fifty-Two Structures

Borderline Personality Disorder maps to 52 distinct Icosa structures. Traps, basins, formations, fault lines, compensations, domain patterns, capacity patterns, paths — all 10 individual structure types in the model. No other diagnosis in this dataset is this geometrically distributed.

PTSD comes closest at 42 structures across 9 types. Severe Major Depressive Disorder reaches 36. Then the count drops fast: Dependent PD at 29, Schizoid PD at 27, OCD and GAD each at 26.

The gap between BPD and everything else is not a measurement artifact. It reflects something clinicians have known for decades: BPD resists single-mechanism explanations. It touches affective regulation, identity, interpersonal functioning, impulsivity, dissociation, self-harm, chronic emptiness. Each of those maps to a different geometric position on the Icosa grid. When a disorder occupies 52 positions across every structure type the model contains, you’re not looking at a single-mechanism syndrome. You’re looking at a condition that has colonized the geometry.

This article examines 703 ICD-10-CM structural correspondences between Icosa and psychiatric diagnosis — a database mapping 65 diagnostic code families to specific positions on a 20-center geometric grid. The live browser now exposes paired ICD-10-CM and ICD-11 terms for those same diagnostic concepts. These correspondences are conceptual bridges for structural understanding, not validated clinical mappings, and they may not be perfectly accurate in every case. Icosa is a structural meta-model for human experience. It does not diagnose, does not compete with the DSM or ICD, and does not replace professional clinical assessment. What it does is show the shape underneath the label — which geometric components are load-bearing in a given diagnosis, which are secondary, and where the structural exits are.

You can explore the full correspondence database interactively.

The Grid

Icosa measures personality on a grid of 20 centers — four capacities crossed with five domains. The capacities are Open (receiving input), Focus (organizing attention), Bond (attaching and belonging), and Move (expressing and acting). The domains are Physical, Emotional, Mental, Relational, and Spiritual. Every intersection — Open x Physical, Focus x Emotional, Bond x Mental, and so on — is a center that can be measured as Under, Centered, or Over.

For the purpose of reading these diagnostic correspondences, six structure types matter most.

Traps are self-reinforcing feedback loops at a single center or two connected centers. Rumination: fixated Focus feeding racing Mental content, racing Mental content feeding fixated Focus. The loop sustains itself. The model contains 134 trap correspondences to diagnoses — the largest single category.

Basins are multi-center attractor states where an entire capacity or domain has shifted. Absent Embodiment: the Physical domain goes offline across all four capacities. You can’t receive through the body, can’t attend to somatic experience, can’t feel bodily belonging, can’t express through the body. The grid has collapsed an entire column. Basins account for 100 diagnostic correspondences.

Formations describe the whole-profile shape — the global configuration of all 20 centers. A Contracted formation means most centers are Under. An Overdriven formation means most are Over. Eighty-four diagnostic correspondences map to formations, concentrated in personality disorders, where the diagnosis describes a pervasive pattern rather than an episodic state.

Fault lines are cascade vulnerabilities — sequences where displacement at one center propagates to adjacent centers along predictable geometric paths. When Sensitivity (Open x Physical) goes Under, the cascade can fire toward Empathy (Open x Emotional), then Inhabitation (Bond x Physical), then Vitality (Move x Physical). This specific cascade — the Foundation Line — appears in PTSD, depression, and somatic disorders. The direction it fires matters. Forty-three diagnostic correspondences map to fault lines.

Compensations are structural workarounds — a capacity or domain that Over-functions to cover for one that’s Under. When Move shuts down and Focus picks up the load, you get analysis substituting for action. When Open collapses and Move surges, you get discharge without intake. Seventy-five diagnostic correspondences map to domain or capacity compensations.

Patterns describe a single capacity or domain that’s displaced across multiple centers without reaching the full-column collapse of a basin. Off-centered capacity patterns (113 entries) and off-centered domain patterns (123 entries) together form the largest portion of the diagnostic correspondence set. These are partial displacements — not the whole system locked, but a specific capacity or domain consistently pulled in one direction.

These structures are not Icosa’s invention layered onto a diagnostic manual. They are geometric positions that the model derives from the mathematics of a 4x5 grid. The correspondences arise because diagnoses, independently described from clinical observation, land on those same positions when mapped structurally.

Where Diagnosis Meets Geometry

The strongest correspondences are the ones where a single Icosa structure captures the defining feature of a diagnosis — not as an analogy, but as a geometric description of the same phenomenon.

PTSD: Two Cascades From One Point

PTSD maps to 42 structures across 9 types, nearly as distributed as BPD. But the most revealing finding is in the fault lines.

The DSM-5-TR organizes PTSD symptoms into clusters. Cluster E (hyperarousal: hypervigilance, exaggerated startle, irritability, reckless behavior, concentration difficulties, sleep disturbance) and Cluster D (negative alterations in cognitions and mood: emotional detachment, diminished interest, persistent negative beliefs, feeling detached from others, inability to experience positive emotions) describe opposite clinical pictures that coexist in the same disorder. The arousal cluster fires the nervous system upward. The cognitive-mood cluster shuts it down.

On the Icosa grid, both cascades originate from the same harmony point: Sensitivity, the intersection of Open and Physical. This is where the body receives raw sensory input. In PTSD, Sensitivity is the site of violation — the body’s receptive gate was overwhelmed by the traumatic input.

When Sensitivity goes Over, the Overwhelm Line fires. Open x Physical floods, cascading through the grid to Empathy, Presence, and Vitality: sensory hyperreactivity, emotional flooding, attentional seizure of the body, somatic agitation. The body receives too much, and everything downstream surges.

Sensitivity going Under triggers the opposite cascade — the Foundation Line. Open x Physical shuts down, propagating through Empathy, Inhabitation, and Vitality: somatic numbing, emotional flatness, loss of bodily belonging, physical depletion. The body stops receiving, and everything downstream starves.

Two opposite fault-line cascades from the same geometric point, firing in opposite directions — that is what the DSM’s two-cluster model corresponds to. One diagnosis, one point of origin, two directional cascades. The clinical observation that PTSD patients oscillate between hyperarousal and numbing maps to a single harmony point toggling between Over and Under states, each time triggering a different cascade pathway.

In the correspondence database, the structural basis puts it directly: PTSD’s dissociative subtype numbing — “persistent inability to experience positive emotions, feelings of detachment, and restricted affect” — is the Emotional domain going offline across all four capacities. Feelings cannot be received, attended to, owned, or expressed.

The clinical utility here is in the directionality. If you know which cascade direction is dominant in a particular patient — whether they’re living mostly in the Overwhelm Line (hyperarousal-dominant) or the Foundation Line (numbing-dominant) — the geometry predicts which centers are under the most strain and which are downstream of the current displacement. For a hyperarousal-dominant patient, the upstream target is Sensitivity itself: the body’s receptive gate that is admitting too much. Grounding, sensory regulation, body-based containment. For a numbing-dominant patient, the target is also Sensitivity, but the task is reopening rather than containing — titrated somatic engagement to bring the body’s reception back online without retriggering the flood. Same origin point. Opposite interventions. The cascade direction tells you which one.

OCD: Thought Eating Action

Analysis Paralysis is a compound trap. Move x Mental is frozen (action inhibited, decision impossible) while Focus x Mental is fixated (analytical loops running, reviewing, checking, re-evaluating). The compound condition means Focus’s fixation on the Mental column is what prevents Move from breaking through — thought becomes a substitute for action that perpetually forestalls it. Focus generates the compulsion. Move absorbs the paralysis. The trap locks because the thinking itself has become the compulsion — the person thinks more to do less.

Analysis Stall, the basin capturing this same compensation at system level, carries the structural basis most relevant to OCD: “The compound condition — fixation preventing the system from breaking out of the thought loop into behavior — captures obsessive doubt and checking without resolution.” The basin describes what happens when the trap pattern scales to a full capacity displacement.

OCD and OCPD both map to Analysis Stall, but through different mechanisms. OCD’s mapping is episodic — the obsessive-compulsive cycle activates the basin during symptom states. OCPD’s mapping is characterological — the basin describes a character structure built around perpetual analysis substituting for authentic expression. “Preoccupation with orderliness, perfectionism, and control at the expense of flexibility, openness, and efficiency” is the DSM’s language. “Move is silenced while Focus over-plans” is the geometry.

Manic Episode: Output Saturates Everything

The Output Escalation basin captures what happens when Move goes Over across every domain simultaneously. Physical agitation. Emotional intensity without proportion. Pressured speech and flight of ideas. Intrusive social engagement. Grandiose purpose-seeking.

A manic episode maps here because its defining features — decreased need for sleep, pressured speech, psychomotor agitation, excessive involvement in activities with painful consequences — are all expressions of the same geometric event: the action-expression capacity flooding every channel at once. The basin quality matters: once Move has saturated all five domains, the state is self-reinforcing. More output generates more stimulation generates more output. The attractor is deep. Pulling out of it requires reducing the Move saturation across the board, not addressing any single behavioral expression.

This is where the structural view adds something. The DSM criteria list manic symptoms as parallel features. The geometry shows them as expressions of a single capacity displacement — which means they share a structural root. Pressured speech and excessive risk-taking aren’t comorbid features; they’re the same capacity (Move Over) expressed through different domains (Mental and Relational/Physical). The treatment target isn’t the speech or the risk-taking. It’s the Move saturation.

Depersonalization: The Body Goes Dark

The Absent Embodiment basin maps to Depersonalization/Derealization Disorder with strong alignment. The structural basis is precise: “The Physical domain going offline across all four capacities. The person cannot receive through the body (Open x Physical offline), cannot focus on somatic experience (Focus x Physical offline), cannot feel bodily belonging (Bond x Physical offline), and cannot express through the body (Move x Physical offline).”

This is the clearest single-structure-to-single-diagnosis correspondence in the diagnostic set. One Icosa basin. One diagnosis. The basin’s definition and the disorder’s phenomenology describe the same experience from different angles — the geometry says “Physical column collapsed” and the clinic says “persistent feelings of detachment from one’s body, as if observing oneself from outside.”

Consider what depersonalization is not, because the correspondence predicts that too. It’s not emotional numbness (that’s the Affective Shutdown basin, Emotional column offline — which maps to PTSD’s dissociative subtype). It’s not cognitive fog (that’s the Attention Drift basin, Focus column collapsed — which maps to delirium). Depersonalization is specifically somatic: the body is gone while other systems may continue functioning. The grid distinguishes these three column-collapse states that clinical presentation can blur.

Panic Disorder and Somatic Symptom Disorder: The Same Basin, Different Timescales

Both Panic Disorder and Somatic Symptom Disorder map to the Embodied Overwhelm basin — the Physical domain saturating all four capacities. But they saturate it differently.

In panic, the saturation is acute. Bodily sensations flood receptivity (Open x Physical surging), seize attentional focus (Focus x Physical locked on the pounding heart), create a terror-bond with somatic experience (Bond x Physical fused to the symptoms), and drive behavioral escape (Move x Physical in flight mode). The basin’s deep-attractor quality matches the self-reinforcing cycle clinicians know: somatic symptoms trigger fear, fear triggers more symptoms, the loop accelerates until exhaustion or intervention breaks it.

In SSD, the saturation is chronic. The Physical domain has captured the whole system at lower intensity but higher persistence. Bodily sensations dominate receptivity (every physical sensation registers as a signal), attention organizes around symptom monitoring (hypervigilance about health, not about acute threat), identity fuses with the sick role (Bond x Physical becomes “I am my symptoms”), and communication channels fill with somatic content (everything the person says is about the body). Same basin, different temporal signature. Panic is a flash flood. SSD is a rising water table.

The geometry predicts that both conditions should respond to interventions targeting the Physical-domain saturation — reducing the body’s monopoly over all four capacities. The prediction matches clinical evidence: interoceptive exposure (targeting Open x Physical), attentional redirection (targeting Focus x Physical), and behavioral activation that engages other domains all have demonstrated efficacy across both conditions, despite their different presentations.

Reactive Attachment Disorder: Bond Column Collapse

The Bond Rupture basin maps to RAD with strong alignment. Bond goes offline across all five domains simultaneously. The child cannot form attachments to people (Relational offline), cannot connect to their own emotions (Emotional offline), shows somatic withdrawal (Physical offline), has restricted cognitive engagement (Mental offline), and demonstrates no investment in meaning or play (Spiritual offline).

The structural basis notes that “the basin’s depth (strong attractor state) corresponds to RAD’s persistence and treatment resistance.” This matters clinically. A deep basin means the system has settled into a state that requires substantial energy to exit. RAD’s well-documented resistance to standard therapeutic interventions — the way children with RAD can seem impervious to warmth, play, and relational repair — maps to the physics of a deep attractor: the displaced state is stable, and perturbations return to it rather than shifting it toward a new configuration.

Convergences That Share a Basin

What happens when diagnostically distinct conditions share the same geometric destination? One pattern runs through the convergence data: they arrive at the same Icosa basin through different entry points. The clinical implications are specific — same structural target, different therapeutic context, different reasons the patient got there. Separation Anxiety and Dependent PD both map to Anxious Gripping — Open shuts down while Bond overcompensates through desperate attachment. “The inability to be openly receptive drives increasingly desperate bonding.” But SAD arrives there through attachment panic (developmental, anxiety-driven), while DPD arrives through characterological dependency (pervasive, ego-syntonic). Same geometric destination. Different clinical roads.

Schizoid PD and Paranoid PD both map to Detached Surveillance — Bond withdraws, Focus compensates by taking analytical distance. The structural basis for the schizoid mapping: “This basin was essentially designed to capture this clinical picture.” The schizoid person watches life from the analytical perimeter. The paranoid person watches from the same perimeter but for different reasons — Bond can’t trust, so Focus monitors for threat. Detached observation as existential preference versus detached observation as threat assessment.

Intermittent Explosive Disorder maps to the Discharge Loop — Open offline, Move explosive. “The inability to receive is compensated by compulsive discharge.” The person can’t take in the situation, others’ perspectives, or modulating input, so expression floods out unregulated. The basin structure predicts that anger management focused solely on output control (Move regulation) will fail unless it also addresses the input closure (Open’s shutdown). If the person still can’t receive, the discharge pressure will rebuild.

What the Grid Cannot See

Of 703 ICD-10-CM correspondence entries, 651 use the relationship type part-of. That’s 92.6%.

This single statistic captures the fundamental difference between the two systems. Diagnostic codes are composites — syndromes assembled from multiple criteria, each criterion potentially mapping to a different Icosa structure. Icosa measures structural atoms — individual centers, specific capacity states, particular domain configurations. When a diagnosis maps as part-of an Icosa structure, it means the geometric position is one component of the clinical picture, not the whole picture.

Only 52 entries (7.4%) qualify as manifests-as — cases where an Icosa structure generates the clinical phenomenon rather than partially overlapping with it. These are the tight correspondences: Absent Embodiment manifests as Depersonalization. Discharge Loop manifests as IED. Detached Surveillance manifests as Schizoid PD. In each case, a single geometric state produces the clinical picture.

The part-of dominance means something specific for practitioners. When you see that Severe MDD maps to 36 Icosa structures, none of those structures IS depression. Each is a component — Action Inhibition (psychomotor retardation), Affective Shutdown (anhedonia), Rumination (negative thought patterns), specific fault-line cascades (vegetative collapse sequences). Depression on the grid is a configuration, not a position. Which components are active, and which are dominant, varies between patients who share the same ICD diagnosis code.

This is the structural reason two patients with identical F32.2 diagnoses can present so differently. One patient’s depression might be dominated by the Action Inhibition basin (everything shutting down) while another’s is dominated by the Rumination trap (trapped in negative thought loops with full energy). Same diagnosis, different geometry. The diagnostic label tells you the syndrome. The grid would tell you which components are load-bearing.

There’s a second divergence worth naming. Icosa doesn’t capture behavioral content. It captures the structural configuration that makes specific behaviors possible, but not the behaviors themselves. OCD maps to Analysis Paralysis — the trap of thought substituting for action. But Icosa has nothing to say about whether the obsessive content is contamination, symmetry, harm, or relationship-themed. The specific fear is invisible to the geometry. What the geometry sees is the structural loop: Focus locked, Move frozen, the thinking-instead-of-acting pattern that all OCD subtypes share regardless of content. Similarly, phobia maps to specific trap and basin structures — the geometry of avoidance, the Open-Under pattern that refuses sensory input — but whether the phobia targets spiders, heights, social evaluation, or blood has no geometric address. The grid measures the structural shape of avoidance, not what is being avoided.

This is a design consequence, not a limitation. By measuring structure rather than content, Icosa captures what different presentations of the same diagnosis share geometrically — which is also what makes transdiagnostic treatment approaches possible. CBT for contamination OCD and CBT for symmetry OCD both work through the same structural target: breaking Focus’s fixation so Move can re-engage. The content varies between patients. The structural loop they share is what the geometry measures and what the intervention addresses.

A third divergence: temporal criteria. The DSM specifies duration thresholds — two weeks for MDD, six months for GAD, one month for PTSD. These timelines are definitional. You can’t diagnose MDD on day twelve. Icosa has no temporal axis. A structural profile is a snapshot of the grid at a given moment. It shows the configuration but not how long the configuration has been in place. Duration, course, onset age, episode frequency — these remain the DSM’s jurisdiction entirely. The structural grid could theoretically show that a person’s profile has been in the same configuration across multiple assessments (suggesting chronicity), but the chronicity itself is a clinical determination, not a geometric one.

And a fourth: severity stratification within a diagnosis. The DSM distinguishes mild, moderate, and severe MDD by symptom count and functional impairment. Icosa’s formations do capture something analogous — a Contracted formation (most centers Under) occupies a different coherence band than a formation in the Strained band (moderate displacement) — but the correspondence is imprecise. Severity in the DSM is a clinical judgment integrating symptom burden, functional loss, and risk. Severity in the geometry is a measurement of how far the grid has deviated from centered. These correlate but are not equivalent.

What the Database Found That Neither System States

Personality disorders span more Icosa structure types than any other diagnostic category. BPD touches all 10 individual types. OCPD and Avoidant PD each touch 10. Dependent PD and Schizoid PD reach 8 and 7 respectively. The personality disorder category collectively accounts for 199 of 703 entries — 28% of the entire ICD-10-CM correspondence set.

Acute episodes behave differently. Manic episodes concentrate in basins (capacity and domain saturation) and a handful of fault lines. Panic disorder concentrates in the Embodied Overwhelm basin and Physical-domain patterns. Delirium concentrates in the Attention Drift basin — Focus collapsed across every domain, the defining feature of delirium rendered as a single capacity going offline. Episodes don’t spread across the geometry. They hit specific structures hard.

The category breakdown shows where the correspondences concentrate: personality disorders account for 199 entries, mood disorders for 108, trauma disorders for 73, anxiety disorders for 70, bipolar-related for 40, dissociative disorders for 40, psychotic disorders for 35, somatic disorders for 33, OCD-related for 29, and neurodevelopmental for 27. Personality disorders generate nearly twice the correspondences of the next-largest category. More structures involved means more geometric territory occupied.

Personality disorders are geometric configurations. They describe the shape of the whole grid — which centers are displaced, which compensations have calcified, which formations the profile occupies. They are distributed because personality IS the whole-grid configuration. A personality disorder doesn’t happen to you. It is the shape you’ve settled into.

Episodes are geometric events. They describe what happens when a specific capacity or domain hits a threshold — a basin activates, a fault line fires, a compensation locks in. They are concentrated because an episode IS a single structural event propagating through the system. An episode happens. It has an onset and, usually, a resolution. The geometry fires and then — if the attractor isn’t too deep — it returns toward baseline.

This distinction — configuration versus event — maps directly to the old Axis I/Axis II distinction that the DSM-5 officially abandoned when it moved to a single-axis system in 2013. The DSM’s reasoning was that the multi-axial system created an artificial hierarchy between “clinical disorders” (Axis I) and “personality disorders” (Axis II). The structural data suggests the distinction was real, just poorly framed. The difference isn’t hierarchical — personality disorders aren’t less important than episodes. The difference is geometric: configurations versus events, distributed versus concentrated, whole-grid shapes versus single-structure activations.

The database didn’t set out to validate the Axis I/II split. It mapped diagnoses to geometric positions and found that the two categories occupy the grid in structurally distinct ways. Personality disorders spread. Episodes concentrate. That pattern held across every diagnosis in the set.

One more finding. The qualifier distribution — strong (43%), moderate (49.6%), weak (7.4%) — shows that weak correspondences are rare. When a diagnosis maps to an Icosa structure, the structural alignment is usually at least moderate. The mapping is not forced. The 7.4% weak entries tend to cluster in conditions where the diagnosis includes features outside Icosa’s structural scope (substance-specific symptoms, medical conditions, developmental timing). The geometry captures what it can capture, and where it can’t, the correspondence weakens rather than fabricating a fit.

Reading the Geometry in Practice

A structural profile is not a clinical diagnosis and never will be. Diagnosis requires history, duration, functional impairment, differential diagnosis, and clinical judgment that no geometric model provides. What Icosa adds is a structural layer underneath the diagnostic label — a map of which components are load-bearing and where the geometry suggests intervention has the most leverage.

A BPD patient presenting with identity disturbance and chronic emptiness occupies different geometric territory than one presenting with affective instability and self-harm. Same F60.31. Different structures. Identity disturbance concentrates in Bond x Mental and Bond x Spiritual — the centers governing self-concept and meaning-making. Chronic emptiness shows as Under-states across Emotional and Spiritual domains. Affective instability concentrates in Emotional-domain Over-states and the Emotionalizing compensation. Self-harm concentrates in Move x Physical Over-states and fault-line cascades through the Physical column. The escape routes run in different directions. The clinician diagnosing BPD uses established diagnostic criteria, and properly so — the label communicates prognosis, guides treatment selection, and coordinates care. The structural profile underneath shows which of BPD’s 52 geometric positions are active in this particular patient, which components are primary versus compensatory, and which centering paths lead away from the most entrenched positions.

The fault-line information is particularly useful for anticipating deterioration. If a patient’s profile shows displacement along the Foundation Line (starting at Sensitivity, cascading through Empathy toward Inhabitation and Vitality), you know the geometric prediction: further displacement at the origin point will propagate downward through those centers in sequence. You can monitor the upstream centers — Sensitivity and Empathy — as early-warning positions. If those centers destabilize, the cascade geometry predicts which centers will be affected next and in what order.

Conversely, the centering paths show where recovery has structural traction. Each displaced center has a geometric path toward its centered state, and some paths are shorter than others. When three centers are displaced and one of them has a shorter centering path, targeting that center first can release compensatory pressure on the other two. The geometry doesn’t tell you which therapeutic technique to use. Your training and the evidence base tell you that. The geometry tells you where to point it.

GAD maps to 26 geometric structures — traps (Rumination, Somatic Hypervigilance), domain patterns (Mental-Over across multiple capacities), capacity patterns (Focus-Over sustaining hypervigilance), compensations (cognitive monitoring substituting for the experiential engagement the person avoids). The structural question: which of those 26 is primary?

A GAD patient dominated by Focus-Over capacity patterns — hypervigilant attention scanning across all domains — needs a different entry point than one dominated by Open-Under domain patterns, where the world feels threatening and receptivity has closed. The first patient’s nervous system is doing too much. The second is receiving too little. Mindfulness-based approaches target Focus regulation directly. Exposure-based approaches reopen the receptive channel. Same diagnosis. The geometric load-bearing structure determines which evidence-based intervention has the most structural leverage.

The compensation structures are particularly telling. When a profile shows a strong compensation — say, Somatizing (emotional distress expressed entirely through the body) alongside a GAD diagnosis — you know that part of the worry pattern is structurally maintained by the physical domain absorbing content that belongs in the Emotional domain. The somatic complaints aren’t a separate problem. They’re the compensation that keeps the primary pattern stable. Treat the somatic complaints as pure medical concerns and the anxiety persists. Address the emotional material the body is carrying and the compensation loosens.

None of this replaces the GAD diagnosis. The code, the criteria, the treatment protocols built on decades of randomized controlled trials — those remain your clinical foundation. The geometry underneath is a structural map of which components are active in this particular patient’s version of the syndrome, which components are compensating for each other, and which cascade paths connect them. Two kinds of information. More useful together than either alone.

703 ICD-10-CM correspondences. 65 diagnostic code families. 10 structure types. The full mapping, including paired ICD-11 terms, is available to explore in the interactive correspondences browser. The geometry underneath your diagnoses has always been there. Now it has coordinates.