This may not be the best possible name for this effect. These visions are usually achieved over longer periods of exercises and combined with the cultivation of positive emotions and attitudes.
Any shortcut bears the potential of 'moving too fast' for one's own sake.
If individual, personal power is being increased without a raise in personal integrity, there is a danger of the person hurting itself or others. The person will usually stop itself before too much damage is done and some of the next exercises are helping work to ameliorate these problems. While this can happen, of course, the argument itself is limited to a rather narrow and mechanistical view of the world. Or, in other words, if a certain part of the brain is being activated during a vision, it would be a rather limited view to postulate that it is 'only the brain' causing this vision to appear and to ignore that there may be a process going on which, as a side effect, makes some parts of the brain being more active. Then the amygdala can be seen as a crucial switch in the operation of a Being that uses the brain to perform tasks and to gain sensations and perceptions.