BDNF and amyotrophic lateral sclerosis: The first studies applying transcranial magnetic stimulation in ALS were conducted by Angelucci and Di Lazzaro and colleagues, who pioneered the use of rTMS at both low frequency (1 Hz) and high frequency (20 Hz) on the motor cortex of four patients, aiming to assess changes in muscle strength, disease progression and serum BDNF levels [71,117].