There is still a controversy if human volitions and actions are governed by causal laws or obeys free will. Neurosciences start to study the neural correlates of free will by investigating how brains make decisions. Here, some of questions about free will are discussed from the neurosciences point of view taking into consideration a neuroeconomic model of decision making. This model is used here with the purpose of providing very formal definitions of key concepts raised in any free will discussion such
as goals, necessity, motivation, etc., and to provide a formal background for discussing decision making. One of the conclusions of this discussion is that free will is computable but unpredictable, therefore not submitted to causal laws. In addition, the electroencephalogram was recorded in an experiment about choice selection of alternative actions and it presented here as an example of how neurosciences may study the neural correlates of free will.