Investopedia contributors come from a range of backgrounds, and over 25 years there have been thousands of expert writers and editors who have contributed. Dr. JeFreda R. Brown is a financial ...

Author contribution: idea and draft of the manuscript, as well as approval of the submitted version. Karl Bjørnar Alstadhaug, specialist in neurology, senior consultant and professor. The author has ...

Trond Sand (born 1952) Specialist in clinical neurophysiology and neurology. Head of section and professor, and wrote his doctoral thesis on evoked potentials in multiple sclerosis. The author has ...