The information exchange between working memory and long-term memory.

A fundamental question in memory research has long been the interplay between briefly maintaining information in working memory (WM) and its enduring retention in long-term memory (LTM). Much of the research has explored how WM processes influence the formation of LTM and, in turn, how stored LTM can either support or disrupt WM performance. This Special Issue of Memory & Cognition brings together cutting-edge research that delves into this relationship, showcasing studies that reveal the latest advances in the field.

Toll-Like Receptor 8 is Expressed in Monocytes in Contrast to Plasmacytoid Dendritic Cells and Mediates Aberrant Interleukin-10 Responses in Patients With Systemic Sclerosis.

Objective: Systemic sclerosis (SSc) is a severe rheumatic disease causing fibrotic tissue rearrangement. Aberrant toll-like receptor (TLR) 8 transcripts in plasmacytoid dendritic cells (pDCs) were recently linked to SSc pathogenesis, which is at least partially mediated by increased type I interferon (IFN-I) responses. Here, we addressed the functional role of TLR8 signaling in different immune cell subsets of patients with SSc.

The benefits of memory control processes in working memory: Comparing effects of self-reported and instructed strategy use.

Working memory performance is often assumed to benefit from different maintenance control strategies such as rehearsal, refreshing, elaboration, and grouping. In studies assessing strategy self-reports, some strategies were indeed associated with better recall. Nevertheless, experimental studies assessing the effect of instructing maintenance strategies compared to a no-instruction baseline lend no evidence for the effectiveness of these strategies for working memory.

When Load is Low, Working Memory is Shielded From Long-Term Memory's Influence.

Previous studies found that episodic long-term memory (eLTM) enhances working memory (WM) performance when both novel and previously learnt word pairs must be retained on a short-term basis. However, there is uncertainty regarding how and when WM draws on eLTM. Three possibilities are (a) that people draw on eLTM only if WM capacity is exceeded; (b) that there is a contribution of eLTM to WM performance, irrespective of whether prior knowledge is helpful or not; or (c) benefits of prior knowledge are specific to comparisons between conditions which are similarly ambiguous concerning whether LTM may be useful.

Grouping in working memory guides chunk formation in long-term memory: Evidence from the Hebb effect.

The Hebb effect refers to the improvement in immediate memory performance on a repeated list compared to unrepeated lists. That is, participants create a long-term memory representation over repetitions, on which they can draw in working memory tests. These long-term memory representations are likely formed by chunk acquisition: The whole list becomes integrated into a single unified representation.

Delayed memory for complex visual stimuli does not benefit from distraction during encoding.

The covert retrieval model (McCabe, Journal of Memory and Language 58(2), 480-494, 2008) postulates that delayed memory performance is enhanced when the encoding of memoranda in working memory (WM) is interrupted by distraction. When subjects are asked to remember stimuli for an immediate memory test, they usually remember them better when the items are presented without distraction, compared to a condition in which a distraction occurs following each item. In a delayed memory test, this effect has been shown to be reversed: Memory performance is better for items followed by distraction than without.

When Does Episodic Memory Contribute to Performance in Tests of Working Memory?

Both the experimental and the psychometric investigation of the WM capacity limit depend critically on the assumption that performance in our tests of WM reflects that capacity limit to a good approximation. Most tasks to measure WM rely on testing memory after a short time during which participants are asked to maintain information in WM. In these tests, episodic long-term memory is likely to also lay down a trace of the memory set.

To be or not to be relevant: Comparing short- and long-term consequences across working memory prioritization procedures.

Priority-based allocation of attentional resources has shown robust effects in working memory (WM) with both cue-based and reward-based prioritization. However, direct comparisons between these effects in WM are needed. Additionally, the consequences of WM prioritization for remembering in the long term remain unclear for both prioritization procedures.

Effects of stress beliefs on the emotional and biological response to acute psychosocial stress in healthy men.

Background: Negative beliefs about stress (e.g., "stress is bad") constitute an independent risk factor for increased morbidity and mortality.

The dynamic clustering of insulin receptor underlies its signaling and is disrupted in insulin resistance.

Insulin receptor (IR) signaling is central to normal metabolic control and is dysregulated in metabolic diseases such as type 2 diabetes. We report here that IR is incorporated into dynamic clusters at the plasma membrane, in the cytoplasm and in the nucleus of human hepatocytes and adipocytes. Insulin stimulation promotes further incorporation of IR into these dynamic clusters in insulin-sensitive cells but not in insulin-resistant cells, where both IR accumulation and dynamic behavior are reduced.

Chunking, boosting, or offloading? Using serial position to investigate long-term memory's enhancement of verbal working memory performance.

Individuals can use information stored in episodic long-term memory (LTM) to optimize performance in a working memory (WM) task, and the WM system negotiates the exchange of information between WM and LTM depending on the current memory load. In this study, we assessed the ability of different accounts of interactions between LTM and WM to explain these findings, by investigating whether the position of pre-learnt information within a memory list encoded into WM affects the benefit it provides to immediate memory. In two experiments we varied the input position of previously learned word-word pairs within a set of four to-be-remembered pairs.

The contribution of episodic long-term memory to working memory for bindings.

The present experiments support two conclusions about the capacity limit of working memory (WM). First, they provide evidence for the Binding Hypothesis, WM capacity is limited by interference between bindings but not items. Second, they show that episodic LTM contributes substantially to binding memory when the capacity of WM is stretched to the limit by larger set sizes.

Expression of IGF-1 receptor and GH receptor in hepatic tissue of patients with nonalcoholic fatty liver disease and nonalcoholic steatohepatitis.

Objective: The GH and IGF-1 axis is a candidate disease-modifying target in nonalcoholic fatty liver disease (NAFLD) given its lipolytic, anti-inflammatory and anti-fibrotic properties. IGF-1 receptor (IGF-1R) and GH receptor (GHR) expression in adult, human hepatic tissue is not well understood across the spectrum of NAFLD severity. Therefore, we sought to investigate hepatic IGF-1R and GHR expression in subjects with NAFLD utilizing gene expression analysis (GEA) and immunohistochemistry (IHC).

Hepatitis B virus-specific CD4 T cell responses differentiate functional cure from chronic surface antigen infection.

Background & Aims: With or without antiviral treatment, few individuals achieve sustained functional cure of chronic hepatitis B virus (HBV) infection. A better definition of what mediates functional cure is essential for improving immunotherapeutic strategies. We aimed to compare HBV-specific T cell responses in patients with different degrees of viral control.

Distinct Hepatic Gene-Expression Patterns of NAFLD in Patients With Obesity.

Approaches to manage nonalcoholic fatty liver disease (NAFLD) are limited by an incomplete understanding of disease pathogenesis. The aim of this study was to identify hepatic gene-expression patterns associated with different patterns of liver injury in a high-risk cohort of adults with obesity. Using the NanoString Technologies (Seattle, WA) nCounter assay, we quantified expression of 795 genes, hypothesized to be involved in hepatic fibrosis, inflammation, and steatosis, in liver tissue from 318 adults with obesity.

Differentiation of exhausted CD8 T cells after termination of chronic antigen stimulation stops short of achieving functional T cell memory.

T cell exhaustion is associated with failure to clear chronic infections and malignant cells. Defining the molecular mechanisms of T cell exhaustion and reinvigoration is essential to improving immunotherapeutic modalities. Here we confirmed pervasive phenotypic, functional and transcriptional differences between memory and exhausted antigen-specific CD8 T cells in human hepatitis C virus (HCV) infection before and after treatment.

Freeing capacity in working memory (WM) through the use of long-term memory (LTM) representations.

Previous research indicates that long-term memory (LTM) may contribute to performance in working memory (WM) tasks. Across 3 experiments, we investigated the extent to which active maintenance in WM can be replaced by relying on information stored in episodic LTM, thereby freeing capacity for additional information in WM. First, participants encoded word pairs into LTM, and then completed a WM task, also involving word pairs.

Tissue-Resident Memory T Cells in the Liver-Unique Characteristics of Local Specialists.

T cells play an important role to build up an effective immune response and are essential in the eradication of pathogens. To establish a long-lasting protection even after a re-challenge with the same pathogen, some T cells differentiate into memory T cells. Recently, a certain subpopulation of memory T cells at different tissue-sites of infection was detected-tissue-resident memory T cells (T cells).

Intrahepatic T17/T Cells in Homeostasis and Disease-It's All About the Balance.

Both acute and chronic hepatic inflammation likely result from an imbalance in the T1/T2 cell response and can lead to liver fibrosis and end-stage liver disease. More recently, a novel CD4+ T helper cell subset was described, characterized by the production of IL-17 and IL-22. These T17 cells 50were predominantly implicated in host defense against infections and in autoimmune diseases.

Reactivated Visual Masks Do Not Disrupt Serial Recall.

The process of spontaneous refreshing plays a central role in current models of working memory but is yet to be observed directly. In a recent study, Rey, Versace, and Plancher (2018) introduced a novel approach to investigate the mechanisms underlying refreshing: They presented tones previously associated with a visual mask during the free time of a complex span task and found that this impaired memory, presumably because reactivation of the masks disrupts refreshing. Here, we aimed to replicate their finding under more controlled settings with more observations per participant.

Dissociating refreshing and elaboration and their impacts on memory.

Maintenance of information in working memory (WM) is assumed to rely on refreshing and elaboration, but clear mechanistic descriptions of these cognitive processes are lacking, and it is unclear whether they are simply two labels for the same process. This fMRI study investigated the extent to which refreshing, elaboration, and repeating of items in WM are distinct neural processes with dissociable behavioral outcomes in WM and long-term memory (LTM). Multivariate pattern analyses of fMRI data revealed differentiable neural signatures for these processes, which we also replicated in an independent sample of older adults.

Does limited working memory capacity underlie age differences in associative long-term memory?

Past research has consistently shown that episodic memory (EM) declines with adult age and, according to the associative-deficit hypothesis, the locus of this decline is binding difficulties. We investigated the importance of establishing and maintaining bindings in working memory (WM) for age differences in associative EM. In Experiment 1 we adapted the presentation rate of word pairs for each participant to achieve 67% correct responses during a WM test of bindings in young and older adults.

The effects of refreshing and elaboration on working memory performance, and their contributions to long-term memory formation.

Refreshing and elaboration are cognitive processes assumed to underlie verbal working-memory maintenance and assumed to support long-term memory formation. Whereas refreshing refers to the attentional focussing on representations, elaboration refers to linking representations in working memory into existing semantic networks. We measured the impact of instructed refreshing and elaboration on working and long-term memory separately, and investigated to what extent both processes are distinct in their contributions to working as well as long-term memory.

Repetitive transcranial magnetic stimulation over dorsolateral prefrontal cortex modulates value-based learning during sequential decision-making.

Adaptive behavior in daily life often requires the ability to acquire and represent sequential contingencies between actions and the associated outcomes. Although accumulating evidence implicates the role of dorsolateral prefrontal cortex (dlPFC) in complex value-based learning and decision-making, direct evidence for involvements of this region in integrating information across sequential decision states is still scarce. Using a 3-stage deterministic Markov decision task, here we applied offline, inhibitory low-frequency 1-Hz repetitive transcranial magnetic stimulation (rTMS) over the left dlPFC in young male adults (n = 31, mean age = 23.