Transcranial Electrical Stimulation (TCES) / Cerebral Blood Flow (CBF) / Xenon Under Computerized Tomography (Xe/CT)
Condition: Healthy Volunteers
Study type: Interventional

Summary: 
      Direct stimulation of the cerebral cortex induces an increase in cerebral blood flow.
      Although this information is known, it has never been documented during Transcranial Cerebral
      Electrical Stimulation (TCES), which is a non invasive technique. It is used to modulate the
      opiate endogenous system, mainly in opioid users but no cerebral blood flow mapping of the
      anatomic regions involved in this modulation of the opiate system under electrical
      stimulation has been performed in functional Computerized Tomography.
    

Detailed description: 
      -  Principal Objective : To compare the increase in mean cerebral blood flow in a group of
           defined zones (the thalamus, anterior cingulate gyrus, the insula, periacqueductal
           region of the brain stem,the frontal lobes, the striatum and limbic system) in healthy
           volunteers stimulated or not stimulated by TCES.

        -  Secondary Objective : Description of cerebral blood flow variations in the different
           zones in order to map electrostimulated areas.

        -  Study design : An experimental, randomized, double-blind, single-centre trial with 2
           groups, a study group (stimulated by TCES) and a control group (not stimulated).

        -  Inclusion criteria : Participants free of any known neurological or psychiatric
           disorder; participants not under treatment particularly with opioids, analgesics or
           medication containing codeine or morphine for at least a month; participants aged
           between 18 and 65 having signed a written informed consent ; participants having
           accepted to be registered on the national eligibility list for subjects participating in
           a trial without direct individual benefit, and covered by an insurance policy.

        -  Exclusion criteria : Participation in two different study trials without direct
           individual benefit at the same time. Contraindications to Computerized Tomography.
           Subjects diagnosed clinically with a Neurological or Psychiatric disorder; Subjects who
           have been under analgesics or morphine agonists for less than a month; Pregnant or
           breastfeeding mothers and women without an adequate contraception. Drug addicts or
           persons under tutelage.

        -  Study plan: Study group: Xe/CT and transcranial electrostimulation / Control group :
           Xe/CT

        -  Principal Criterion of Judgement: difference in mean cerebral blood flow between the
           study group(stimulated) and the control group (not stimulated).

        -  Secondary Criteria of Judgement : Difference in mean cerebral blood flow region per
           region (thalamus, anterior cingulate gyrus, insula, periacqueductal region of the brain
           stem, the frontal lobes, the striatum and limbic system).

        -  Number of subjects : 40

        -  Duration of subject participation in study : 2 H 30
    

Intervention name(s): TCES
Intervention type(s): Device
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double
Primary purpose: Treatment
Keywords: cerebral blood flow; electrical stimulation; Computed Tomography Scanner, X-Ray; Brain Mapping