The Effect of Transcranial Direct-Current Stimulation of Right Anterior Superior Temporal Sulcus in Adults Related to Autism Traits

7 
 
1.1. History of Transcranial Electrical Stimulation 
 Electrical stimulation has a long history and received interest since Roman 
Empire. In 43 AD, the physician Scribonious Largus wrote about the first type of 
transcutaneous electrical nerve stimulation (TENS) for therapeutic purpose. He 
described the effects of the application of electric torpedo fish over painful regions, 
such as the head in case of headaches. The electrical shock induced by torpedo fish 
immediately led to a transient period of pain relief (Gater et Al., 2011).  
 Luigi Galvani (1737 – 1798), an Italian physician, is considered the father of 
modern electrophysiology thanks to his animal electricity experiments and the 
invention of the voltaic cell in 18
th
 century.   
 At the same time, in France, the physician Charles Le Roy (1726 – 1779) 
started to use electricity to induce effects on physiological functions. The most famous 
experiment of Le Roy is his attempt to restore the sight of a blind man through the 
application of conducting wires around his head. Le Roy administered 12 shocks and 
even if the treatment was repeated several times and the patient remained blind, he 
perceived flashes of light (phosphines) (Pascual-Leone and Wagner, 2007). 
 More recently, in 1802 Giovanni Aldini (1762 – 1834) wrote the first report 
about the electrical stimulation of the human cortex. In particular he did experiments 
with electrical stimulation to treat melancholia and psychosis.  
 Researches on non-invasive brain stimulation continued through 19
th
 and 20
th
 
centuries, leading to the discovery of many electronic devices such as pacemakers and 
defibrillators. These innovations led to a better understanding of nervous structures 
and their mechanisms of functions.