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It's important to note that this is talking about normal brain neurogenesis. We have long known that external stimulus such as ECT, and chemicals such as 25i-nb

It's important to note that this is talking about normal brain neurogenesis. We have long known that external stimulus such as ECT, and chemicals such as 25i-nbome are neurogenic.

JPLeRouzic 8y ago
Please can you elaborate on this? Thanks!
- superkuh 8y ago
  In the human brain the hippocampus is actually 2 hippocampuses, one for each hemisphere. They are a little curled structures like two 'C' facing each other with the top of one nested in the hollow of the other. Where the end of one C nests inside the other there's a region called the dentate gyrus. In the dentate gyrus there are small granular cells. Beneath this layer are stem cell capable of becoming neurons. Most of the activty of the dentate gyrus birthing new neurons is in during early development and when a baby. During these times there's a stream neurons from the sub-granular zone (beneath the granular cells in the dentate gyrus in the hippocampus). The perceptions of the external environment and the internal physiological state modulate the rate of survival of these new neurons. It's kind of open in the sub-granular zone and the stem cells are able to move freely and assume multiple intermediate cell architectures before finally becoming dentate granule neurons that migrate to and integrate with the existing hippocampal circuitry along the other parts of the two nesting C shapes. They're even somewhat glia-like during part of this intermediate development. It's a complex process that's easy to interrupt. Most of the cells die and do not become integrated into the hippocampus. So, to get to and restate the question: how do neuroactive chemicals and things like ECT potentially alter the rate of new sub-granular zone stem cells? If the current development state of the cell has receptors or the glia around it are effected by chemicals that bind to those receptors it's easy to see how things could be thrown off. It is not necessarily a good thing to increase the rate of cell survival of new neurons in the adult. The rate of new neurons has important effects on the ability of the neuronal circuits in the rest of the hippocampus (involving CA1, CA3, etc) to do the types of memory encoding tasks researchers call pattern separation and pattern completion. So while there are indeed chemical and electrophysiological ways to increase the the survival rate of new neurons there should be reasons to believe the balance needed to be adjusted up. Just as a throwaway, THC is one of the chemical compounds found to increase new dentate granual neuron survival and integration.
  - JPLeRouzic 8y ago
    Impressive answer! Many thanks.
  - kick_in_the_dor 8y ago
    Fascinating! Do you have any sources for those interested in reading more about these theories of neuronal growth and the process of pattern separation/pattern completion in the Hippocampus?
    - SubiculumCode 8y ago
      I just wanted to pipe in and say that parent is knowledgeable upon this subject.
    - superkuh 8y ago
      Yes, some. http://erewhon.superkuh.com/library/Neuroscience/Hippocampal%20Formation/ http://erewhon.superkuh.com/library/Neuroscience/Hippocampal...
      - kick_in_the_dor 8y ago
        Thank you!
  - jonathanleane 8y ago
    THC or CBD?
pier25 8y ago
25i-nbome? The psychedelic substance?
- blackflame7000 8y ago
  Yea I don't think synthetic LSD makes you smarter haha.
  - chisleu 8y ago
    However, psilocybin (the active component of magic mushrooms) is also a strong neurogenic compound, although not as effective as ECT. 25i-nbome is much stronger than ECT, even in tiny doses which are far below the threshold for any noticeable changes to perception.
    - blackflame7000 8y ago
      I mean if that's what you call getting high now then go for it. You are completely discounting any damaging effects and the associated disconnect with reality.
- scythe 8y ago
  25i-nbome is a popular ligand for 5-ht2a activation due to its high potency (low amount required for action), stability, and iodine content (can be made radioactive without altering the structure). Someone probably had a thought about 5-ht2a stimulation leading to neurogenesis and tested it in mice using 25i because it's a good compound for that. Thus the headline "25i-nbome causes brain cell growth". (The psychedelic action of 5-ht2a ligands may have been a clue that they cause neurogenesis. Until tested it's only a guess.)
- chisleu 8y ago
  Yes. There is a doctor at the University of South Florida that was investigating it, and many LSD "micro-dosers" switched to using 25i-nbome even though it is very much a research chemical with no long-term safety profile.
rubicon33 8y ago
So are SSRI's. They promote neurogenesis in the hippocampus via BDNF. It's theorized as one of the reasons for the therapeutic effects of SSRIs that tend to only come about after ~2-6 weeks of use.

It's important to note that this is talking about normal brain neurogenesis. We have long known that external stimulus such as ECT, and chemicals such as 25i-nbome are neurogenic.

JPLeRouzic 8y ago

Please can you elaborate on this? Thanks!

superkuh 8y ago
In the human brain the hippocampus is actually 2 hippocampuses, one for each hemisphere. They are a little curled structures like two 'C' facing each other with the top of one nested in the hollow of the other. Where the end of one C nests inside the other there's a region called the dentate gyrus. In the dentate gyrus there are small granular cells. Beneath this layer are stem cell capable of becoming neurons. Most of the activty of the dentate gyrus birthing new neurons is in during early development and when a baby. During these times there's a stream neurons from the sub-granular zone (beneath the granular cells in the dentate gyrus in the hippocampus). The perceptions of the external environment and the internal physiological state modulate the rate of survival of these new neurons. It's kind of open in the sub-granular zone and the stem cells are able to move freely and assume multiple intermediate cell architectures before finally becoming dentate granule neurons that migrate to and integrate with the existing hippocampal circuitry along the other parts of the two nesting C shapes. They're even somewhat glia-like during part of this intermediate development. It's a complex process that's easy to interrupt. Most of the cells die and do not become integrated into the hippocampus. So, to get to and restate the question: how do neuroactive chemicals and things like ECT potentially alter the rate of new sub-granular zone stem cells? If the current development state of the cell has receptors or the glia around it are effected by chemicals that bind to those receptors it's easy to see how things could be thrown off. It is not necessarily a good thing to increase the rate of cell survival of new neurons in the adult. The rate of new neurons has important effects on the ability of the neuronal circuits in the rest of the hippocampus (involving CA1, CA3, etc) to do the types of memory encoding tasks researchers call pattern separation and pattern completion. So while there are indeed chemical and electrophysiological ways to increase the the survival rate of new neurons there should be reasons to believe the balance needed to be adjusted up. Just as a throwaway, THC is one of the chemical compounds found to increase new dentate granual neuron survival and integration.
- JPLeRouzic 8y ago
  Impressive answer! Many thanks.
- kick_in_the_dor 8y ago
  Fascinating! Do you have any sources for those interested in reading more about these theories of neuronal growth and the process of pattern separation/pattern completion in the Hippocampus?
  - SubiculumCode 8y ago
    I just wanted to pipe in and say that parent is knowledgeable upon this subject.
  - superkuh 8y ago
    Yes, some. http://erewhon.superkuh.com/library/Neuroscience/Hippocampal%20Formation/ http://erewhon.superkuh.com/library/Neuroscience/Hippocampal...
    - kick_in_the_dor 8y ago
      Thank you!
- jonathanleane 8y ago
  THC or CBD?

pier25 8y ago

25i-nbome? The psychedelic substance?

blackflame7000 8y ago
Yea I don't think synthetic LSD makes you smarter haha.
- chisleu 8y ago
  However, psilocybin (the active component of magic mushrooms) is also a strong neurogenic compound, although not as effective as ECT. 25i-nbome is much stronger than ECT, even in tiny doses which are far below the threshold for any noticeable changes to perception.
  - blackflame7000 8y ago
    I mean if that's what you call getting high now then go for it. You are completely discounting any damaging effects and the associated disconnect with reality.
scythe 8y ago
25i-nbome is a popular ligand for 5-ht2a activation due to its high potency (low amount required for action), stability, and iodine content (can be made radioactive without altering the structure). Someone probably had a thought about 5-ht2a stimulation leading to neurogenesis and tested it in mice using 25i because it's a good compound for that. Thus the headline "25i-nbome causes brain cell growth". (The psychedelic action of 5-ht2a ligands may have been a clue that they cause neurogenesis. Until tested it's only a guess.)
chisleu 8y ago
Yes. There is a doctor at the University of South Florida that was investigating it, and many LSD "micro-dosers" switched to using 25i-nbome even though it is very much a research chemical with no long-term safety profile.

rubicon33 8y ago

So are SSRI's. They promote neurogenesis in the hippocampus via BDNF. It's theorized as one of the reasons for the therapeutic effects of SSRIs that tend to only come about after ~2-6 weeks of use.