The 'other form of consciousness' formulated by James is now called 'altered states of consciousness', abbreviated as ASCs. However, this concept is difficult to define. For example, there is the question of whether we should define ASCs objectively or subjectively. If we choose an objective definition, then we are talking about the causes of the changed consciousness. We would then make a definition based on narcotics. A problem, however, is that you do not include the subjective experience in the definition. For example, how can we know if people who are drunk are all reacting in the same way? Is it also possible that the same drugs produce different ASCs?Perhaps it is better to define ASCs in terms of physical variables and behavioral measurements. In this context one can think of heartbeat and the expression of emotions. A problem with such an approach, however, is that few ASCs are associated with unique physical patterns or behavioral changes. For this reason, scientists are still cautious when it comes to giving a definition based on physical processes to the state of consciousness (SoC) to.It is also possible to give ASCs a subjective definition. In practice, this approach is used the most. In these types of definitions, ASCs are described as states in which it feels as if there is a change in the normal pattern of mental functioning. These types of definitions give rise to other problems. ASCs are compared with normal patterns of mental functioning, but what exactly is a normal pattern of mental functioning? In addition, the use of subjective definitions ensures that people's experiences can not be compared properly, because they can not be measured in the same way. What exactly changes when someone experiences an ASC? We can say that consciousness has changed, but what exactly does this mean?...