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Volcic-tentacles t1_itfssh9 wrote

"boost dopamine levels" is a nonsense phrase.
"Projected to the hippocampus" is also nonsense.

Dopamine is a neurotransmitter. It is manufactured and stored in small vesicles at the extremities of neurons and is released into synapses: whereupon it is reabsorbed or destroyed within milliseconds. Neurotransmitters are not like other hormones such as adrenaline or thyroxine that are released into the blood supply. There is little or no dopamine sloshing around in your brain. There are only dopaminergic neurons, i.e. neurons that use dopamine to transmit signals across a synapse. And yes, rewards are mediated by dopaminergic neurons, but so are dozens of other processes.

How we increase levels of a neurotransmitter in a synapse, and what the actual effects of that are is very poorly understood. How we measure the amount of dopamine in a synapse is not clear since they are just 20-40 nanometers wide: one could not use visible light to see one and do spectroscopy for example. Blue light wavelengths are an order of magnitude longer than a synapse, i.e. 450 and 495 nanometers.

So there are a chain of inferences in the story as presented that don't seem valid to me.

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ryarger t1_itfvkby wrote

OP’s title is not the actual article’s headline. The article and actual article headline do not have the issues you’ve pointed out.

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[deleted] t1_itgk80p wrote

[deleted]

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CueCappa t1_ithy777 wrote

I'm glad he made the comment correcting the post's title because I'm sure there are a lot of people that only read the title and comments for a tl;dr.

Not me though, I totally read the whole thing. Yup, definitely.

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Viikoreaux t1_ith4hi1 wrote

I was just thinking this title makes zero sense

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Electrical-Smile-636 t1_ithjeoe wrote

As the first author of the paper I would like to straighten out that we did not manipulate or measure dopamine in this study (we conducted it in a Science Museum in Amsterdam, so we used purely behavioral measures). Also note that the notion of hippocampal dopamine underlying the effects of novelty comes from a robust literature in animals (mostly studies that do use pharmacological manipulations and neuroscientific measures). The formulation of "dopamine projecting to the hippocampus" dates back to an influential theory by Lisman & Grace 2005, which is why this wording is still prevalent in the literature.

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Minute-Object t1_itgfmlh wrote

If one uses a dopamine reuptake inhibitor, does that not increase the total amount of dopamine in the neurons and synapses?

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PM-ME-DEM-NUDES-GIRL t1_itisr0f wrote

yes, it does increase the amount of extracellular dopamine and the amount of dopamine neurotransmission (how much dopamine is reaching receptors) but it may not cause a persistent increase in the total amount of dopamine as there are homeostatic mechanisms that decrease dopamine synthesis when extracellular dopamine is elevated and vice versa.

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