Neural, Behavioural, and Clinical Effects of tDCS in PDOC; Feasibility Study (RAINDROP)

University of Birmingham

Status: Unknown

Conditions: Brain Injuries; Vegetative State; Consciousness Disorder; Minimally Conscious State

Treatments: Other: Transcranial direct current stimulation

Study type: Interventional

Funder types: Other

Identifiers

NCT04248946

RG_18-269

Details and patient eligibility

About

This study evaluates the feasibility of an experimental protocol that combines advanced multi-modal imaging of the brain with clinical and behavioural scales to characterise the neural, behavioural, and clinical effects of transcranial direct current stimulation (tDCS) for rehabilitation in PDOC

Full description

Patients with prolonged disorders of consciousness (PDOC) have very limited therapeutic options, and they often show little to no progress over time. Here, the investigators will assess whether transcranial direct current stimulation can improve patients' responsiveness. The investigators will use a protocol designed to target specific brain networks that have been shown to play a key role in explaining the lack of voluntary responses in PDOC. The study will focus on characterising the mechanisms of action of tDCS and the bases for potential individual differences in responsiveness to the stimulation across participants. This feasibility study is the first step towards developing personalised tDCS interventions to restore external responsiveness in PDOC patients. Its results will inform the design of a future trial fully powered for characterising neural, behavioural, and clinical effects of tDCS in PDOC as well as the mechanisms underlying individual differences in responsiveness.

Enrollment: 15 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Aged 18 years or older
• Receiving care at a recruitment site, with a consensus clinical diagnosis of PDOC from any aetiology (i.e. traumatic or non-traumatic injury).
• Stable and with no need of mechanical support (i.e. respirator, etc.)

Exclusion criteria

• Scalp skin sores or any skin damage at the electrode sites
• Metallic implants in the face or skull
• Craniectomy or cranioplasty
• No evidence of auditory startle in clinical observations, or absent brainstem auditory evoked potentials in recent clinical history (if data available)
• MRI incompatible: metal plates incompatible with MRI scanners, pacemaker, inability to lay flat for prolonged periods of time, aneurysm clips, neurostimulators, brain/subdural electrodes, etc. (MRI stream ONLY)

Trial design

Primary purpose: Basic Science

Allocation: Non-Randomized

Interventional model: Crossover Assignment

Masking: Quadruple Blind

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15 participants in 2 patient groups

MRI stream

Experimental group

Description:

In this stream all patients receive 2 experimental interventions (anodal tDCS and cathodal tDCS) and a sham intervention (sham tDCS). These are delivered in randomised order, ensuring a balanced distribution of participants across possible orders. They will receive 5 sessions per condition (on consecutive days), for a total of 15 sessions. I. Anodal, cathodal, sham II. Anodal, sham, cathodal III. Cathodal, anodal, sham IV. Cathodal, sham, anodal V. Sham, anodal, cathodal VI. Sham, cathodal, anodal

Treatment:

Other: Transcranial direct current stimulation

Bedside stream

Experimental group

Description:

In this stream all patients receive 1 experimental interventions (either anodal tDCS or cathodal tDCS) and 1 sham intervention (sham tDCS). These include only 1 session per condition and are delivered in randomised order, resulting in the following possible combinations: I. Anodal, sham II. Cathodal, sham III. Sham, anodal IV. Sham, cathodal Participants will be randomly assigned to the above groups ensuring a balanced distribution of participants across them.

Treatment:

Other: Transcranial direct current stimulation