The aim of the study is to investigate the neural mechanisms underpinning transcranial direct current stimulation (tDCS), a non-invasive neuromodulation technique in which a direct current is passed through scalp electrodes. A series of experiments will be conducted to understand and characterize the transcranial and transcutaneous mechanisms of tDCS. To investigate this research question, every participant will undergo three stimulation conditions (active, sham and control). In the control condition, an anaesthetic cream will be applied to anaesthetize the nerves in the scalp. In addition, the effectiveness of tDCS and peripheral nerve stimulation will be compared. Ultimately, the obtained knowledge can lead to the development of improved non-invasive neuromodulation therapies, which can lead to more effective treatments of a variety of neurological and psychiatric disorders.

Inclusion Criteria:

• good general health

Exclusion Criteria:

• Epilepsy or family history of epilepsy
• Migraine
• Allergic to lidocaine or benzocaine
• Pregnant
• History of or currently suffering from:
• neurological diseases
• psychiatric diseases, depression or anxiety (Annex B and Annex C)
• History of:
• brain surgery
• brain thrombosis
• cerebral hemorrhage
• severe head trauma
• meningitis
• long period of loss of consciousness (> 1 hour)
• Metal parts in the head or upper body:
• Defibrillator, implanted medication pump
• Metal prosthesis in ear, hart, …
• Deep brain stimulator
• Coronary bypass or intracranial or aneurysm clips (brain arteries, aorta, etc.)