## Project Overview ## This project is now complete. A Stage 2 Registered Report manuscript is now under review at eNeuro (pre-print is here: https://psyarxiv.com/h59jv) **Abstract from Stage 2 Manuscript** : There is fundamental debate about the nature of forgetting: some have argued that it represents the decay of the memory trace, others that the memory trace persists but becomes inaccessible due to retrieval failure. These different accounts of forgetting lead to different predictions about savings memory, the rapid re-learning of seemingly forgotten information. If forgetting is due to decay, then savings requires re-encoding and should thus involve the same mechanisms as initial learning. If forgetting is due to retrieval failure, then savings should be mechanistically distinct from encoding. In this registered report we conducted a pre-registered and rigorous test between these accounts of forgetting. Specifically, we used microarray to characterize the transcriptional correlates of a new memory (1 day after training), a forgotten memory (8 days after training), and a savings memory (8 days after training but with a reminder on day 7 to evoke a long-term savings memory) for sensitization in Aplysia californica (n = 8 samples/group). We found that the re-activation of sensitization during savings does not involve a substantial transcriptional response. Thus, savings is transcriptionally distinct relative to a newer (1-day old) memory, with no co-regulated transcripts, negligible similarity in regulation-ranked ordering of transcripts, and a negligible correlation in training-induced changes in gene expression (r = .04 95% CI [-.12, .20]). Overall, our results suggest that forgetting of sensitization memory represents retrieval failure. These project pages have: * Our pre-registered protocols, sample-size plans, and predictions. * All data, analysis scripts, and outputs * Both the Stage 1 manuscripts that were submitted and revised prior to pre-registration and the Stage 2 manuscript now submitted for publication. * **Project status:** Complete * **Last update:** 7/8/2020 * **Pre-registrations:** We developed this project and successfully sought funding. We collected initial samples as proof of concept and tested our microarray analysis script. We then submitted the manuscript to pre-registered review at *eNeuro*. After revision [our proposal has been accepted][1]. We pre-registered the project on 9/11/2019 (https://osf.io/fqh8j). We then completed the project as specified. All data and analysis scripts are now posted as well as a pre-print of the Stage 2 manuscript now under review. ## Project components: ## **Data** * [Behavioral data][2] * Microarray data is in [the files section][3]: \microarray analysis\arraydata and also posted to the [Geo database][4] **Analysis Scripts** * [Final analysis script for behavioral data][5] * [Final pre-registered analysis script for microarray data][6] * [Final script for the exploratory analyses of microarray data][7] *For analysis scripts, download the entire folder and any subfolders, as there are often ancillary files required in addition to the main R script linked above* **Proposal and pre-registration information** * [Stage 1 Proposal, First Submission][8] * [Stage 1 Proposal, Accepted/Second Submission][9] * [Pre-registreation][10] ### Outdated components ### * First draft of [Registered-report proposal manuscript][11] and [title page][12] * Initial [Experimental Protocol][13] * Initial [Behavioral Analysis Plan][14] * Initial [Microarray Analysis Plan][15] [1]: https://osf.io/ykcqe/ [2]: https://osf.io/cn7ta/ [3]: https://osf.io/cn7ta/ [4]: https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE152045 [5]: https://osf.io/c7zgh/ [6]: https://osf.io/acfwu/ [7]: https://osf.io/wr5qz/ [8]: https://osf.io/gzpmt/ [9]: https://osf.io/ykcqe/ [10]: https://osf.io/fqh8j [11]: https://osf.io/rshvm/ [12]: https://osf.io/jcxsr/ [13]: https://osf.io/z2uck/wiki/Experimental%20Protocol/ [14]: https://osf.io/z2uck/wiki/Behavioral%20Analysis%20Plan/ [15]: https://osf.io/z2uck/wiki/Microarray%20Analysis%20Plan/