Astral Codex Ten

VTA

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VTA

Article

VTA is a recurring concept in the Astral Codex Ten archive, appearing 3 times across 3 issues between September 30, 2022 and August 13, 2024. The archive places it in contexts such as ““VTA GABA neurons convey to DA neurons how much reward to expect””; “ventral tegmental area (VTA), which contains the dopamine neurons”; “the VTA is also part of this system”. It most often appears alongside dopamine, fMRI, mesocortical pathway.

Metadata

  • Category: Concepts
  • Mention count: 3
  • Issue count: 3
  • First seen: September 30, 2022
  • Last seen: August 13, 2024

Appears In

Source Context

Recovered passages from the original issue text. When the raw archive preserved outbound links inside the source passage, they are listed directly under the quote.

Highlights From The Comments On Unpredictable Reward
September 30, 2022 · Original source
1. A "state prediction error" or general surprise signal from PFC (either directly or via pedunculopontine nucleus and related structures). This provokes phasic bursting of dopamine neurons in the Ventral Tegmental Area.
Most people think this is the case because when you put subjects in an fMRI scanner and have them do tasks where they get reward or learn cues that are associated with reward, you robustly get RPE-related BOLD activity in the NAc, and only rarely/more weakly in the ventral tegmental area (VTA), which contains the dopamine neurons that project to the NAc. So when you see those nice fMRI maps, the NAc is lit up in red. But the physiological basis of this fMRI signal is hotly debated (for example, it could represent primarily synaptic input rather than actual neuronal firing, especially in a GABAergic circuit like the striatum), and in single-unit recordings in mice, rats, and monkeys, it is unequivocal that dopamine neurons in the VTA show much more RPE signaling than the striatum.
I felt bad that I didn’t already know all this despite purportedly having studied some neuroscience, so I looked into a paper on the subject recommended by commenter JDK. Now I feel less bad. The paper seems to be arguing something different, saying things like “VTA GABA neurons convey to DA neurons how much reward to expect” and “VTA GABA neurons inhibit DA neurons when reward is expected, causally contributing to prediction-error calculations”.
Inline links: a paper, recommended
Highlights From The Comments On Jhanas
October 31, 2022 · Original source
> H5: Jhanas should show increased activation compared to the rest state in the dopamine reward system of the brain (NAc in the ventral striatum and medial OFC). A broad range of external rewards stimulate this system (food, sex, beautiful music, and monetary awards), so extreme joy in jhana may be triggered by the same system (the VTA is also part of this system, but is too small to image with standard fMRI methods, but see [35] for successful imaging methods).
Why Does Ozempic Cure All Diseases?
August 13, 2024 · Original source
Let’s go back to the second pathway by which GLP-1 causes weight loss, which goes through the mesolimbic system, aka ventral tegmental area and nucleus accumbens, aka the reward center.
Inline links: goes through the mesolimbic system
The nucleus tractus solitarii uses neurotransmitter-GLP-1 to inhibit the ventral tegmental area, which then releases less dopamine into the nucleus accumbens. Dopamine levels in the nucleus accumbens act as a multiplier for reward (that is, a given reward feels more rewarding when there’s high dopamine in those areas).