🧠 Exposure and Response Prevention (ERP) Simulator

Trigger Exposure — Facing the Obsession Without the Ritual

The patient deliberately contacts the feared trigger, ritual withheld from the start.

• In vivo: Exposure type (real contact, not imagined)
• 0%: Ritual permitted (response fully blocked)
• 45 min: Session length (standard ERP block)
• ~1–2 / 10: Starting anxiety (pre-exposure baseline)

Choosing the exposure target

Hierarchy-ranked trigger selected with therapist beforehand.

Setting the no-ritual rule

Patient agrees: no washing, checking, or reassurance seeking.

Anxiety Spikes — The Sharp Rise Toward Peak Distress

Contact with the trigger drives anxiety up quickly, often within minutes.

• ~3–5 min: Time to peak (rapid initial climb)
• 8–9.5 / 10: Peak intensity (first session, untreated)
• High: Physiological arousal (heart rate, sweating rise)
• Activated: Catastrophic belief ("something bad will happen")

Why anxiety spikes so fast

Threat appraisal triggers immediate fight-or-flight activation.

Distress is expected, not avoided

The spike is the therapeutic entry point, not a failure.

Compulsion Prevented — Resisting the Urge to Ritualize

The urge to perform the compulsion peaks alongside anxiety, and is blocked.

• Peaks w/ anxiety: Urge strength (tracks distress curve)
• None: Ritual performed (response fully prevented)
• Coaching: Therapist role (support without reassurance)
• Extinction learning: Key mechanism (no ritual, no reinforcement)

Breaking the compulsion loop

Ritual normally relieves anxiety fast — that relief is withheld.

Urge surfing through the peak

Patient rides out the urge without acting on it.

The Habituation Curve — Anxiety Declines Without the Ritual

Left alone, anxiety falls on its own as the brain updates its threat estimate.

• Exponential: Decline pattern (fast then gradual taper)
• ~2–4 / 10: End-of-session anxiety (well below the peak)
• No catastrophe: Learning signal (expectancy violated safely)
• ~50–70%: Within-session drop (peak to session end)

Habituation, not suppression

Anxiety fades naturally; it is not pushed down by will.

Inhibitory learning model

A new, safer association forms alongside the old fear memory.

Across Sessions — Lower Peaks, Faster Habituation Over Time

Repeated ERP sessions blunt the peak and shorten the time needed to calm.

• ~5.2 / 10: Peak after 10 sessions (down from ~9.4)
• Faster: Habituation speed (shorter τ each session)
• Retained: Between-session learning (gains carry to next visit)
• 12–20 sessions: Typical ERP course (per clinical protocols)

Between-session habituation

Starting anxiety and peak both drop session over session.

Consolidating treatment gains

Cumulative exposure reshapes the trigger's learned meaning.

Ten sessions in, the same trigger produces roughly half the original peak distress.