Rats know when they remember: transfer of metacognitive responding across odor-based delayed match-to-sample tests
Metamemory entails cognitively assessing the strength of one’s memories. We tested the ability of nine Long-Evans rats to distinguish between remembering and forgetting by presenting a decline option that allowed a four-choice odor-based delayed match to sample (DMTS) tests to be by-passed. Rats performed significantly better on tests they chose to take than on tests they were forced to take, indicating metacognitive responding. However, rather than control by internal mnemonic cues, one alternative explanation is that decline use is based on external test-specific cues that become associated with increased rewards overtime. To examine this possibility, we tested rats on three generalization tests in which external contingencies were inconsistent and therefore could not serve as discriminative cues. Rats transferred adaptive use of the decline response in tests that eliminated memory by presenting no sample, increased memory by presenting multiple samples, and both weakened and strengthened memory by varying the retention interval. Further, subjects chose to take or decline the test before encountering the memory test, providing evidence that rats based their metacognitive responding on internal cues rather than external ones. To our knowledge, this is the first robust evidence for metamemory in rats using the DMTS decline-test paradigm in which several possible sources of external stimulus control can be ruled out.
KeywordsMetamemory Executive control Metacognition Monitoring Explicit memory Declarative memory
Regina Paxton Gazes, Taylor B. Wise, and Benjamin M. Basile provided helpful comments on earlier drafts of this manuscript. Emily Kathryn Brown provided useful consultation during planning of Experiment 1 with regard to selecting an appropriate set-size. Kristin Palframan helped collect data in Experiment 1 and 2 and provided useful consult during planning of experiments. Research reported in this study was supported by an Institutional Development Award (IDeA) Network for Biomedical Research Excellence from the National Institute of General Medical Sciences of the National Institutes of Health under Grant Numbers P20GM103430 and P20GM203430 and a Medical Research Grant from the Rhode Island Foundation (2014-4397). These experiments comply with US law.
- Beran MJ, Menzel CR, Parrish AE, Perdue BM, Sayers K, Smith JD, Washburn DA (2016a) Primate cognition: attention, episodic memory, prospective memory, self-control, and metacognition as examples of cognitive control in nonhuman primates. Wiley Interdiscip Rev Cogn Sci 7(5):294–316. doi: 10.1002/wcs.1397 CrossRefPubMedGoogle Scholar
- Dunlosky J, Bjork RA (eds) (2008) Handbook of memory and metamemory. Psychology Press, New YorkGoogle Scholar
- Eichenbaum H (2005) The hippocampus and episodic memory: cognitive and neural mechanisms. Neuropsychopharmacol 30:S37–S37Google Scholar
- Hampton RR (2003a) Rhesus monkeys know when they remember. Proc Natl Acad Sci USA 98(3):5359–5362Google Scholar
- Jozefowiez KJ, Staddon JER, Cerutti DT (2009) Metacognition in animals: how do we know that they know? Comp Cogn Behav Rev 4:29–39Google Scholar
- Keppel G, Wickens TD (2004) Design and analysis, a researchers handbook, 4th edn. Pearson, Upper Saddle RoberGoogle Scholar
- Nelson TO (ed) (1992) Metacognition: core readings. Allyn & Bacon, TorontoGoogle Scholar
- Shettleworth SJ (2010) Cognition, evolution, and behavior, 2nd edn. Oxford University Press, New YorkGoogle Scholar