Transcranial electrical stimulation (tDCS, tACS, tRNS)

Domain IX · Biomedical, neuro & digital

What it is

Transcranial electrical stimulation (tES) passes a weak electrical current through electrodes on the scalp. The aim is to change brain activity without surgery and without inducing a seizure. EU device law groups three forms together as equipment that applies electrical currents to modify neuronal…

Format

• Goals: recognise when a client with depression might benefit from a medical review that includes neuromodulation options; give balanced information; refer.
• Format: within ordinary therapy sessions.

Who practises it, and how they are trained or regulated

• Version followed: prescription home-use and clinic tDCS for depression, as described in the US FDA premarket approval for the Flow FL-100 (PMA P230024, approved 8 December 2025) and its Summary of Safety and Effectiveness Data (SSED); NICE HealthTech guidance HTG382 (published 26 August 2015 as IPG530); and the IFCN/ESBS-endorsed low-intensity transcranial electrical stimulation safety guideline (Antal et al., 2017)…
• What it is. Transcranial electrical stimulation (tES) passes a weak electrical current through electrodes on the scalp. The aim is to change brain activity without surgery and without inducing a seizure. EU device law groups three forms together as equipment that applies electrical currents to modify neuronal activity in the brain: transcranial direct-current stimulation (tDCS, a constant current), transcranial…
• Who delivers it. A psychotherapist does not prescribe, set or deliver tES. In the US the Flow FL-100 is prescription-only and is used at home under a licensed clinician's supervision. The prescribers named are psychiatrists, primary care physicians and psychiatric nurse practitioners. In the NHS, NICE describes tDCS as usually given by a trained clinician, though patients can self-administer it. Research tES should…

Questions to explore with your client

• What drew you to it, and what are you hoping it will change?
• Is there physical contact? Was it explained beforehand, and do you feel free to say no or stop at any point?
• Does it involve any substance, plant preparation, remedy or supplement? Has your doctor or prescriber been told, especially about any medication you take?
• Is it a group, retreat or community? How do they respond if someone wants to leave or raises a concern?
• How do you and the practitioner understand what is happening, in spiritual or cultural terms? Is that a source of comfort, worry, or both?
• Who runs it, and what training or registration do they hold?
• What actually happens in a session or meeting, and how often?
• What does it cost, and is there pressure to commit to more?
• How do you feel afterwards, in the hours and days that follow?
• Does it fit with, or clash with, the work we do here?

What practitioners of it watch for

• confusion about who holds clinical responsibility. Settle it explicitly.
• hopelessness if the client sees no early change. Good sign: the client can say their plan aloud.
• relapse, or disappointment if the course did not help. Process this, and support a further medical review.
• concealment and minimising. Good sign: the client stops, gets checked, and engages with a supervised option.
• passive waiting for the device to work. Good sign: the client takes up activity and skills alongside the device.

When to involve someone else

• New or worsening physical symptoms, or advice to stop or change prescribed medication: involve the client's doctor or prescriber.
• Signs of coercion, isolation from family and friends, escalating costs or secrecy: discuss openly and consider safeguarding.
• A crisis or thoughts of suicide: follow your crisis protocol. In the US, call or text 988; in the UK and Ireland, Samaritans on 116 123.

Drawn automatically from the guide's own sections. Stay curious: neither endorse nor dismiss what the client values, and check anything that matters against the full guide and its sources. Not medical advice.