Reducing False Recognition in the Deese-Roediger/McDermott Paradigm: Related Lures Reveal How Distinctive Encoding Improves Encoding and Monitoring Processes

In the Deese-Roediger/McDermott (DRM) paradigm, distinctive encoding of list items typically reduces false recognition of critical lures relative to a read-only control. This reduction can be due to enhanced item-specific processing, reduced relational processing, and/or increased test-based monitoring. However, it is unclear whether distinctive encoding reduces false recognition in a selective or global manner. To examine this question, participants studied DRM lists using a distinctive item-specific anagram generation task and then completed a recognition test which included both DRM critical lures and either strongly related lures (Experiment 1) or weakly related lures (Experiment 2). Compared to a read-control group, the generate groups showed increased correct recognition and decreased false recognition of all lure types. We then estimated the separate contributions of encoding and retrieval processes using signal-detection indices. Generation improved correct recognition by both increasing encoding of memory information for list words and by increasing memory monitoring at test. Generation reduced false recognition by reducing the encoding of memory information and by increasing memory monitoring at test. The reduction in false recognition was equivalent for critical lures and related lures, indicating that generation globally reduces the encoding of related non-presented items at study (not just critical lures), while globally increasing list-theme-based monitoring at test

Regulation of T Cell Priming by Lymphoid Stroma

The priming of immune T cells by their interaction with dendritic cells (DCs) in lymph nodes (LN), one of the early events in productive adaptive immune responses, occurs on a scaffold of lymphoid stromal cells, which have largely been seen as support cells or sources of chemokines and homeostatic growth factors. Here we show that murine fibroblastic reticular cells (FRCs), isolated from LN of B6 mice, play a more direct role in the immune response by sensing and modulating T cell activation through their upregulation of inducible nitric oxide synthase (iNOS) in response to early T cell IFNγ production. Stromal iNOS, which only functions in very close proximity, attenuates responses to inflammatory DC immunization but not to other priming regimens and preferentially affects Th1 cells rather than Th2. The resultant nitric oxide production does not affect T cell-DC coupling or initial calcium signaling, but restricts homotypic T cell clustering, cell cycle progression, and proliferation. Stromal feedback inhibition thus provides basal attenuation of T cell responses, particularly those characterized by strong local inflammatory cues

Multiple Species of Distinctiveness In Memory? Comparing Encoding Versus Statistical Distinctiveness On Recognition

© 2020 Informa UK Limited, trading as Taylor & Francis Group. The distinctiveness effect refers to the memorial benefit of processing unique or item-specific features of a memory set relative to a non-distinctive control. Traditional distinctiveness effects are accounted for based on qualitative differences in how distinctive items are encoded and subsequently retrieved. This study evaluates whether a separate species of distinctiveness–statistical distinctiveness–may provide an additional benefit to memory beyond traditional task-based processes. Statistical distinctiveness refers to the relative frequency with which a specific memory item or set is processed. The current study examined the presence of statistical distinctiveness through a series of levels-of-processing mixed groups in which related lists were studied using two of the following three tasks to promote either shallow (“E” identification), neutral (reading silently), or deep/distinctive (pleasantness ratings) processing followed by a recognition test. Participants studied lists in which these tasks were used frequently (80% of lists), equally (50% of lists), or infrequently (20% of lists). No recognition advantage was found when tasks were completed infrequently versus frequently. Instead, recognition was greatest for the deeper/more distinctive task–a pattern consistent with an encoding but not a statistical distinctiveness account

Distinctive Encoding of a Subset of DRM Lists Yields Not Only Benefits, But Also Costs and Spillovers

Prior research has emphasized that performing distinctive encoding on a subset of lists in the DRM paradigm suppresses false recognition; we show that its benefits can be mitigated by costs and spillover effects. Within groups read half the DRM lists and solved anagrams for the other half using a strategy that emphasized either item-specific or relational processing. Their recognition was compared to three pure-list control groups (read, item-specific generation, relational generation). Correct recognition in the within groups showed a benefit for generate items and a cost for read items, resulting in little net improvement relative to pure reading. False recognition in the within groups was reduced following item-specific vs. relational generation, but there was again little net improvement. Most surprisingly, false recognition in the within groups was greater for generate than read lists. This pattern suggests that relational processing of read lists spilled over to generate lists, boosting false recognition for generate lists. Distinctive encoding of a subset of items does not appear to globally improve memory accuracy