# The same neuron sometimes released different neurotransmitters, so how does this affect our interpretation of computational models?

Most studies I see compare firing rate with some observed variable (stimuli or behavior). However, they treat all spikes the same. But neurons sometimes release different neurotransmitters depending on the situation, meaning not all spikes are the same. Does this affect our interpretation of these studies? Are there models that account for this? Do spikes vary in any other way?

For example, knowing when a neuron is acting as excitatory versus inhibitory may vastly change our interpretation of it's role.

Additionally this may become even more of an issue when we attempt to model or predict from multiple channels as we are potentially missing out on a crucial piece of information. Without that, do we even have the ability to fully understand the area?

On a slightly different note: Are there other aspects of a neuron output that are important in it's computational role in the circuit? Why don't we take into account it's amplitude over-time for example?

My primary worry is that we are averaging away, or outright throwing away, a lot of information that which could be insightful.

• Frankly our understanding of the specifics of neural codes is limited enough to make these special cases a non issue. For the most part a single principle neurotransmitter is released. Others are not primarily neurotransmitters but have modulatory effects. Would help if you cited this though because the citation would make these things more clear. – Bryan Krause Aug 9 '19 at 4:10
• What evidence do you have that neurons release different neurotransmitters in different situations? I don't believe that is true. – honi Aug 9 '19 at 15:00
• @Bryan Krause is it assumed that a single principle neurotransmitter is released in the whole brain? – Borut Flis Aug 10 '19 at 6:36
• @BorutFlis For any single cell in the whole brain, yes. Of course different cells release different principle neurotransmitters. Other substances like neuropeptides may also be released but they do not have nearly the same function. – Bryan Krause Aug 10 '19 at 11:47
• @guest My primary worry is that we are averaging away, or outright throwing away, a lot of information that which could be insightful This is the peril of modeling in science, but it's a necessary part of making things that we study tractable! – Chuck Sherrington Aug 11 '19 at 1:45