Thought acceleration (also known as racing thoughts  ) is the experience of thought processes being sped up significantly in comparison to that of everyday sobriety.   When experiencing this effect, it will often feel as if one rapid-fire thought after the other is being generated in incredibly quick succession. Thoughts while undergoing this effect are not necessarily qualitatively different, but greater in their volume and speed. However, they are commonly associated with a change in mood that can be either positive or negative. 
Thought acceleration is often accompanied by other coinciding effects such as stimulation, anxiety, and analysis enhancement in a manner which not only increases the speed of thought but also significantly enhances the sharpness of a person's mental clarity. It is most commonly induced under the influence of moderate dosages of stimulant and nootropic compounds, such as amphetamine, methylphenidate, modafinil, and MDMA. However, it can also occur under the influence of certain stimulating psychedelics such as LSD, 2C-E, DOC, AMT.
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