Answers to the most common questions about EMDR therapy, bilateral stimulation, and using apps as EMDR tools.
EMDR (Eye Movement Desensitization and Reprocessing) is a structured psychotherapy developed by Francine Shapiro in the late 1980s. It uses bilateral stimulation — alternating left-right sensory input — while the client processes a distressing memory, reducing its emotional charge over time. EMDR is recognized by the World Health Organization (WHO), the American Psychological Association (APA), and the VA/DoD as a first-line treatment for PTSD.
Bilateral stimulation (BLS) is any sensory input that alternates between the left and right sides of the body in a rhythmic pattern. In EMDR it can be visual (tracking a moving light or finger), auditory (alternating tones in headphones), or tactile (alternating vibrations or taps in each hand). All three modalities are used clinically with comparable effectiveness. TheraJoy delivers all three in one iPhone app.
EMDR is among the most well-researched trauma therapies available. Multiple meta-analyses show it produces significant, durable reductions in PTSD symptoms — often faster than traditional talk therapy. It is recommended as a first-line treatment by the WHO, APA, and VA/DoD. The research notes page has a collection of foundational studies.
It depends on the complexity of the trauma history. For a single-incident trauma in an otherwise stable individual, meaningful progress often occurs in 3–6 sessions. Complex or developmental trauma — repeated abuse, neglect, multiple events over time — typically requires longer treatment. EMDR consistently achieves comparable outcomes to other trauma therapies, often in fewer sessions.
Limited between-session practice is possible for therapist-assigned protocols — primarily resourcing and containment using slow bilateral stimulation. Open-ended trauma reprocessing should only happen with a trained clinician present. Apps like TheraJoy make it straightforward for clients to run assigned home protocols with the exact speed and intensity a therapist specifies. See the self-directed EMDR guide for what's appropriate and what to avoid.
Tactile: a gentle alternating vibration or tap in each hand — left, then right, then left. Most clients describe it as noticeable but not distracting. Auditory: a soft tone alternating between left and right ears through headphones. Visual: tracking a moving light or the therapist's fingers side to side — similar to watching a slow pendulum. All three are mildly absorbing without being intrusive.
For in-person therapy, the therapist provides the bilateral stimulation equipment. For remote sessions or between-session practice, clients need their own BLS source. Apps like TheraJoy deliver all three modalities through an iPhone — tactile via Joy-Con controllers (which many clients already own from Nintendo Switch), auditory through any headphones, and visual on-screen. See EMDR tools for therapists for how this works across a full practice.
Joy-Con controllers are the wireless Bluetooth controllers included with the Nintendo Switch gaming console. They contain precision linear resonance actuator (LRA) haptic motors — the same hardware class as iPhone's Taptic Engine — that produce clean, distinct vibrations. TheraJoy uses Joy-Con haptics for tactile bilateral stimulation, delivering the same haptic quality as dedicated clinical tappers ($100–$450) through hardware that costs around $80 and many clients already own. See the Joy-Con setup guide for pairing instructions.
Therapist-led EMDR sessions typically cost $100–$300 per hour depending on location, therapist credentials, and insurance coverage. The bilateral stimulation tool — if using an app rather than dedicated hardware — costs significantly less. TheraJoy is free to download with a 7-day trial; Plus is $49/yr for solo sessions, Pro is $79/yr for therapist-led remote sessions. Dedicated hardware tappers cost $100–$600 per unit.
EMDR is considered safe when administered by a trained therapist following established protocols. Temporary discomfort during processing sessions is normal — the therapy is working through difficult material. Between-session app use for therapist-assigned resourcing is generally low-risk. Open-ended trauma processing without clinician supervision carries more risk and is not recommended. TheraJoy includes a safety and disclaimer page covering appropriate use.
All three bilateral stimulation modalities. Therapist-led remote sessions. Joy-Con precision haptics. No credit card needed for the trial.
Download on the App Store