There are dozens of neurotransmitters in the human brain. How do neuroscientists decide which transmitters are most important? Are there trends and fashions in neuroscience, such that some transmitters rise and fall in popularity? I searched PubMed for nine different neurotransmitters, and downloaded the 'Results by Year' data to track the number of peer-reviewed papers published each year from 1960 to 2014. The results are very interesting:
Here are some of my observations in no particular order: The stagnation of serotonin (red): after growing steadily from 1960 to 2005, the number of papers about serotonin has flat-lined. This is possibly a reflection of the stagnation of research into selective serotonin re-uptake inhibitor (SSRI) antidepressants which likewise plateaued around 2005 (although it has started to grow again lately, unlike serotonin). This, in turn, may be related to the fact that most of the SSRI drugs went off-patent around this period. However, ...
