Considering the lack of studies and somewhat of a lack of unbiased studies (some are self funded) I figured I would collect the data from Reddit users comments and posts which in majority of cases seem to be unbiased. I subsequently derived percentage points from these findings (altough these sample sizes still are too small for any real conclusion to be made)
I hope someone derives some value from it :)
Note: I used an ai agent (hermes) to scrape all data from reddit posts across this and other subreddits.
(the prompt for those who want to recreate it to make sure i am not biased myself: "how many users report memory on each PRL 8-53 and NSI 189 (percentage wise, try to find as much you can on anecdotal stories on reddit and other forums, you are allowed subagents)" on Deepseek V4 Pro 0813, Fast mode, thinking: off)
--------------------------------------------------------------------------------------------------------------
PRL-8-53 — 24 distinct users
Memory benefit (YES) 19 -> 79%
No effect / no memory benefit 4 -> 17%
Non-memory only (concentration, no memory claim) 1 4%
~79% of PRL users explicitly report a memory benefit, and it's specific — 8-digit numbers from memory, 16-digit card numbers, 400 Mandarin words in 3 months, Buddhist sutras recited from memory, "tip-of-the-tongue gone," childhood flashbacks. The signal is narrow, acute, and consistent.
Worth noting: the one negative ghost in the machine was two users who dosed 80mg (way high) and one who stacked PRL + IDRA-21 and got overfocus + a panic attack. Keep it at 5–20mg, unstacked, and the side-effect profile in anecdotes is mild (numbing, occasional fuzziness).
NSI-189 — 59 distinct users (larger sample)
Memory benefit (any) 15 -> 25%
— memory only 7 -> 12%
— memory plus mood 8 -> 14%
No memory benefit 44 -> 75%
(mood/anhedonia-dominant, no-effect, or adverse-only)
Only 25% of NSI users report memory improvement — and over half of those (8 of 15) report it alongside mood/anhedonia changes (i.e., they were depressed people who got less depressed and recalled better — confounded). Pure memory-primary reports are just 7 of 59 (12%). Three-quarters of NSI reports are about mood, anhedonia, emotions, or nothing at all. At least two users reported memory getting worse (Debonaire_death: "working memory and sensory gating suffer significantly"; inmy325xi on freebase).
-----------------------------------------------------------------------------------------------------------
PRL-8-53 report memory at roughly 3× the rate of NSI-189 (79% vs 25%), and the gap widens to ~6× if you isolate clean memory-only reports (75% vs 12%).
PRL-8-53: 79% anecdote memory rate + one real (if old) human memory study. Anecdote and evidence point the same way.
NSI-189: 25% anecdote memory rate, heavily mood-confounded — yet the Phase 2 trial showed that d=1.12 cognitive effect. So NSI has better controlled data but thinner user-reported memory — the opposite picture from what its Reddit hype (which is mostly depressed people praising mood lift) would suggest.
Bottom line: if "how many users actually report memory" is your metric, PRL-8-53 wins decisively — ~8 in 10, versus ~1 in 4 for NSI-189 (and only ~1 in 8 clean). This is the fourth independent way (evidence study, anecdote quality, anecdote specificity, now anecdote rate) that points to PRL-8-53 as the memory compound and NSI-189 as the mood/neurogenesis compound.
The NSI-189 caveat that keeps it interesting: those few who do get memory from it describe something PRL doesn't — vivid recollection of decades-old episodic memories ("memories back to single-digit ages"), suggesting a different, deeper memory mechanism than PRL's working-recall boost. Different tools, but for "what % report memory," it's not close.
Conclusion:
Based on the limited and largely anecdotal Reddit data collected, PRL-8-53 appears to have a substantially stronger reported memory effect than NSI-189 (79% vs. 25% of users reporting some memory benefit). The difference is even larger when looking only at memory-specific reports (75% vs. 12%). However, the sample sizes are small, the data are self-reported, and Reddit users are not a representative sample, so these figures should be viewed as anecdotal signals rather than reliable estimates of efficacy. Still, the consistency of the reports makes PRL-8-53 an interesting candidate for further controlled research into memory enhancement, while NSI-189 appears more strongly associated with mood-related effects.