Deep brain stimulation (DBS) is an increasingly used surgical treatment for a range of neurological
disorders, most commonly movement disorders. DBS provides durable electrical stimulation
in different regions of the human brain according to a disorder specific manner. The mechanisms of
action of DBS, particularly the interfaces between electrodes and brain are not well known and disputed.
The interfaces have an impact on the outcome of the stimulation. This article presents an insight
of electrochemical consideration at electrode-brain interface, the effects of electrode geometry, and the
effect of current density distribution on the stimulation outcome. The understanding of the interface
permits DBS to successfully treat a certain neurological disorder. The article also investigates the process and importance
of charge balancing in neurons, and the hardware-related complications. Charge balancing technique enables DBS to yield
a more predictable outcome and to be systematically developed as an effective treatment with minimum side effects.
Moreover, the article synthesizes theoretical and empirical findings to provide a guidance for the selection of stimulus parameters.
In this paper, experimental results, clinical studies, and human studies are reviewed. To spur on engineering and
medical advances that will make DBS as a reliable and effective treatment for neurological disorders as cardiac pacemaker
is now, the electrode-brain interfaces need to be continually re-assessed, the charge in brain might be balanced, and
stimulation parameters need to be optimized.