That doesn’t sound completely far fetched. This is a topic I too would like to know more about so if you ever get the time to do the research I’d be curious to see as well.
-GC
I've done quite a bit of research, and from the studies I've read meth stimulates neurogenesis in doses ranging from 50mg - 200mg (for a 220lb individual). It's actually quite interesting because I think most all users will agree that 50mg (or more) is
NOT a "low dose" (for someone with zero tolerance) and therefore must be neurotoxic / non-neurogenic. However, from a scientific standpoint a "low dose" is commonly referenced as 50mg - 200mg (
for a 220lb person). High/Neurotoxic doses are almost solely cited as doses in excess of 500mg (
for a 220lb person). It gets even more interesting because 95% of the studies out there that reference meth neurotoxicity (or even meth in general!)
start with a dose of 500mg, and go up from there (up to 3000mg+! LOL!) Like, do you think a
3-GRAM dose is neurotoxic? Do you think!? And what user uses 500mg in a dose!? Maybe someone who has been using for a decade? (Although I guess your typical meth addict will commonly use 500mg-1000mg+ in a day, but not a dose).
Take for example this study from 2016:
Long-Term Treatment with Low Doses of Methamphetamine Promotes Neuronal Differentiation and Strengthens Long-Term Potentiation of Glutamatergic Synapses onto Dentate Granule Neurons, which studies the neurogenic effects of meth. The dosages involved in this study?
200mg/dose (for a 220lb man). That's what they're citing as a "low dose". I personally find the last paragraph of the study to be fascinating:
In conclusion, the present work shows that long-term administration with a low dose of METH promoted the differentiation of immature neurons and enhanced LTP in differentiating and mature DGCs. It will be fundamental to understand how prolonged use of METH will convert such “positive” effects on neurogenesis and synaptic plasticity into the well known dysfunctional effects that strongly impair cognitive performance in METH-addicted subjects.
There's something we're missing. At certain dosages, meth is apparently able to cause positive neurogenic activity which somehow (possibly) leads to negative/damaging/dysfunctional cognitive activity down the road (with prolonged use). This is where my "Neurogenic
and Neurotoxic" comment comes from - although once again I'm not sure if that comment is accurate.
And then you have this (rather interesting) study from just last year
Methamphetamine and Modulation Functionality of the Prelimbic Cortex for Developing a Possible Treatment of Alzheimer’s Disease in an Animal Model which cites a "low dose" as
100mg/dose (for a 220lb individual). Based on the study, a 100mg dose provides for significant enhancements in neurogenesis/neural activity/synaptic plasticity/cognition. The conclusion reads as follows:
Using a low dose of 1 mg/kg MAMPH with three continuous administrations in the present study produced CTA conditioned learning, increases in plasma corticosterone levels, and enhancements in neural activity in c-Fos expression, and neural plasticity in p-ERK expression in the cognitive function areas (the mPFC, e.g., Cg1, PrL, and IL), the affected brain areas (the rewarding NAc and rewarding and aversive BLA), and the spatial learning and memory brain areas (the hippocampus’ CA3 and DG). Additionally, the excitation of the PrL neurons induced more enhancements for neural activity and neural plasticity in the PrL and IL of the mPFC’s subareas, indicating that a low dose of MAMPH in conjunction with the excitation of PrL neurons might lead to a higher level of neural activity and plasticity than a single MAMPH administration in ameliorating cognitive functions. Therefore, low doses of MAMPH and the modulation of PrL neurons might provide a possible treatment for certain symptoms of AD.
Finally, you have this study (which I'm sure everyone on here is familiar with) the one I've blasted on here over and over again (my apologies) The neuroprotective potential of low-dose methamphetamine in preclinical models of stroke and traumatic brain injury (RIP Dr. Paulsen) The results of which actually resulted in a Patent for Reducing Brain Cell Damage or Death. This study looks at dosages of 50mg/dose (for a 220lb individual) and concludes that:
In all of our studies using low dose methamphetamine we have not found any evidence of neuropathology caused by the drug treatment. To the contrary, we have observed a reduction in neuronal loss, apoptotic cell death, and neuromotor/cognitive impairment after acute brain injury. In light of the fact that low dose methamphetamine is FDA approved for use in juveniles and adults, we see no valid reason why it cannot be utilized in human clinical trials for stroke and TBI. We propose that low dose methamphetamine has significant potential as a neuroprotective agent when the dosing is kept within safe, previously established guidelines.
Basically, at the end of the day, what we (as users) consider a "low dose" (5-25mg for someone with no tolerance) isn't necessarily what the scientific community considers a low dose. Once again, scientifically speaking a low dose is referred to as 50mg-200mg, but would I recommend someone with zero tolerance to dose anything more than 50mg? Hell no. Do I consider 100mg, 200mg to be a low dose? Hell no! But, according to the research I've done (and I've done a lot...),
and unless I'm missing something, a low (neurogenic) dose is commonly referenced as anywhere from 50mg-200mg (
for a 220lb individual). Which I think we can all agree is rather surprising.
Now, am I saying (low-dose) meth is harmless and to go out and use (low-dose) meth? No. Meth is definitely dangerous as hell, even in low doses. I never used more than 200mg/day (a dose considered to be "low" by the scientific community) and I ended up going batshit crazy on it after several years. But based on my research it's not necessarily as wholly-damaging
to all parts of the brain as the general public has been lead to believe.
There's something weird going on with meth, in certain dosages (and in certain pathways) it has these weird (extremely) beneficial effects on certain parts of the brain that down the road, with repeated use, potentially directly (or indirectly) translate into extremely negative effects on others. We're in the process of trying to figure out the exact how and why that is, but we're still a long ways out from nailing it down cold.
While we've learned a metric fuck-ton about how exactly (meth) impacts the brain the past 20 years, there's a lot we don't quite understand, and even more we don't quite understand about the brain in general. What would be ideal is if we could somehow "bio-engineer" meth (“Bio-Meth”
@Atomic_Decay 
) such that we could isolate it's beneficial properties/pathways from it's detrimental properties/pathways and create some sort of new drug/medication. I think that's where a lot of this research is headed. Some of these studies as of late are downright
WILD, primarily these two which were published just last year:
Methamphetamine and Modulation Functionality of the Prelimbic Cortex for Developing a Possible Treatment of Alzheimer’s Disease in an Animal Model
Potential Neuroprotective Mechanisms of Methamphetamine Treatment in Traumatic Brain Injury Defined by Large-Scale IonStar-Based Quantitative Proteomics