i dont know much about the chemicals but your examples have explained exactly what works for me in terms of being productivecompleting school work     setting a cozy temperature my weighted blanket  chill relaxing music and coffee   i also leave my phone downstairs   for me another big one is taking the time to organize my thoughts  writing out a simple step by step guide or organizing the ideas i want to convey in an essay and connecting them together before writing   it makes actually writing much less frustrating and actually can be rewarding as i get into the flow of what im doing - which i cant do without the environment and removing the frustration elements    well said   thanks for bringing this up i hadnt really thought about it this way before