Clearly, chemical processes are vital to the regulation of the nervous system, yet we rarely think about our ‘dopamine level’ or how our neuropeptides are doing. But consider this everyday example:...

Clearly, chemical processes are vital to the regulation of the nervous system, yet we rarely think about our ‘dopamine level’ or how our neuropeptides are doing. But consider this everyday example: caffeine is a chemical that many of us use regularly in tea, coffee, cola drinks and chocolate; we may even joke about not being able to get started in the morning without our caffeine jolt. and we’re right in thinking that caffeine does increase our arousal: in moderation, it makes us more energetic, alert and attentive, as well as improving our mood. The basis for these effects is that caffeine increases the receptivity of dopamine receptors, which has been found to increase our arousal level (Lorist and Tops 2003). how would you explain the tension we feel when we ingest too much caffeine? and how would you expect your behaviour to change if you suddenly stopped using caffeine?