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PubMed1979

Visual and verbal memory for objects and their spatial locations.

Four experiments assessed the role of verbal and visual processing in memory for aspects of a simulated, real-world spatial display. Subjects viewed a three-dimensional model of a city with 16 bulidings that were placed on the display. The buildings were represented on the model with or without an accompanying name label on each buliding. After studying the display, subjects were tested on recall and recognition of the building names, picture recognition of the buildings, and spatial memory for where the bulidings had been located. Overall picture recognition accuracy was low, and the presence of a name label on each building significantly reduced picture recognition accuracy but improved relocation accuracy. Spatial location information was not encoded independently of verbal and visual identity information. However, location information was more accurately retained with memory for verbal than visual aspects of the stimuli. The results are discussed in terms of the theoretical importance of differentiating memory for the identity of visual stimuli from descriptive memory for their physical characteristics in "visual memory" research.

Discrimination, Psychological↗
PubMed1997

Independent regulation of cutaneous lymphocyte-associated antigen expression and cytokine synthesis phenotype during human CD4+ memory T cell differentiation.

Although considerable attention has been paid to the development of cytokine synthesis heterogeneity during memory T cell differentiation, little information is available on how this function is coregulated with homing receptor expression. The development of skin-homing, CD4+ memory T cells in the human provides an excellent model for such investigation, since 1) the skin supports both Th1- and Th2-predominant responses in different settings, and 2) the skin-homing capability of human memory T cells correlates with and appears to depend on expression of the skin-selective homing receptor cutaneous lymphocyte-associated Ag (CLA). In this study, we used multiparameter FACS analysis to examine expression of CLA vs IFN-gamma, IL-4, and IL-2 synthesis capabilities among fresh peripheral blood CD4+ memory T cells, and Th1 vs Th2 memory T cells generated in vitro from purified CD4+ naive precursors by cyclic activation in polarizing culture conditions. Among normal peripheral blood T cells, CLA expression was essentially identical among the IFN-gamma- vs IL-4-producing CD4+ memory subsets, clearly indicating the existence of in vivo mechanisms capable of producing both Th1 vs Th2 skin-homing T cells. In vitro differentiation of naive CD4+ T cells confirmed the independent regulation of CLA and all three cytokines examined, regulation that allowed differential production of IFN-gamma-, IL-4-, and IL-2-producing, CLA+ memory subsets. These studies also 1) demonstrated differences in regulatory factor activity depending on the differentiation status of the responding cell, and 2) revealed CLA expression to be much more rapidly reversible on established memory cells than cytokine synthesis capabilities.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1997

Visual and verbal short-term memory deficits in childhood leukemia survivors after intrathecal chemotherapy.

Assessed survivors of childhood lymphoblastic leukemia (ALL) treated with intrathecal chemotherapy, using the Wide Range Assessment of Memory and Learning (WRAML), compared to controls without cancer, matched as closely as possible in age, SES, and gender. Mild, but consistent, deficits were found in both visual-spatial and verbal single-trial memory tasks. In multitrial learning, only visual-spatial tasks resulted in deficient scores, while verbal learning was within the normal range. IQ results indicated scores 10-20 points lower in the ALL group. Memory results are related to deficits in strategic planning and attentional distractiveness. The WRAML may be a useful clinical tool to evaluate differential memory deficits in children with ALL.

Adolescent↗
PubMed1998

Olfactory memory: the long and short of it.

It has been proposed that memory for odors does not have a short-term (or working) memory system. The distinction between short- and long-term memory in other sensory modalities has been generally supported by three main lines of evidence: capacity differences between the proposed systems, evidence of differential coding, and differential memory losses in neuropsychological patients. The present paper examines these issues in an effort to establish a similar distinction for the memory of olfactory stimuli. Each of these lines of evidence is examined in relation to the literature on olfactory memory. Based on this examination, it seems that there is at least preliminary support from each of these lines of evidence to advocate a distinction between a long- and short-term memory for olfactory stimuli. Emphasis is placed upon the qualitative similarity of olfactory memory to other memory systems. This similarity is further highlighted through an examination of the literature pertinent to serial position effects in memory for olfactory stimuli.

Humans↗
PubMed2006

Glucocorticoid receptors and beta-adrenoceptors in basolateral amygdala modulate synaptic plasticity in hippocampal dentate gyrus, but not in area CA1.

The basolateral amygdala (BLA) is a key structure in a memory-modulatory system that regulates stress and stress hormones (glucocorticoid and noradrenaline) effects on hippocampal functioning. We have shown previously that priming the amygdala differentially affects plasticity in the hippocampal dentate gyrus (DG) and CA1, and mimicked acute stress effect on plasticity in these two subregions. In the present study, we investigated the mechanisms that mobilize the BLA to differentially alter plasticity in DG and CA1. Glucocorticoid receptors antagonist RU 38486 or beta-adrenoceptor antagonist propranolol were microinfused in the BLA, 10 min prior to BLA activation-induced modulation of long-term potentiation (LTP) in DG and CA1. The results showed that neither glucocorticoid nor noradrenergic transmissions in the BLA are necessary for LTP induction and for the impairing effect of amygdala activation on CA1 LTP. In contrast, blockade of glucocorticoid or noradrenergic transmission in BLA, increased baseline synaptic transmission in the DG, but suppressed the enhancing effect of BLA activation on DG LTP. These findings provide further evidence for a differential amygdala control of hippocampal subregions as well as for differential memory processes involving CA1 and DG. They also provide insight into how stress hormones exert their actions on the circuits involved in these processes.

Adrenergic beta-Antagonists↗
PubMed1997

Clinical correlates of memory in schizophrenia: differential links between depression, positive and negative symptoms, and two types of memory impairment.

OBJECTIVE: This study investigated clinical correlates of memory impairment in schizophrenic patients. In particular, the authors hypothesized that depressive symptoms would be linked to memory efficiency, as found in other clinical populations. In addition, they tested Frith's pathophysiological model predicting links between negative symptoms and failure to respond, as well as between positive symptoms and production of erroneous responses. METHOD: Thirty-one patients were given several memory tasks: long-term free recall of nonorganizable and organizable lists in immediate and delayed conditions, recognition in immediate and delayed conditions, implicit memory (stem completion task), and short-term memory (digit span). Superficial encoding of information was also assessed by the ability to recall the items sequentially; deep encoding was assessed by the ability to organize the items according to their semantic properties. Two types of memory measures were individualized: measures reflecting memory efficiency and measures reflecting production of erroneous memory responses (intrusions, perseverations, false alarms). RESULTS: Consistent correlations appeared between severity of depressive symptoms and measures reflecting deep but not superficial encoding; none, however, was correlated with negative symptoms. Two of the three types of erroneous memory responses were positively linked to positive symptoms. CONCLUSIONS: Efficiency of memory processes relying on deep encoding seemed linked to depressive symptoms. In addition, the two distinct types of impairment predicted by Frith's model were found. The expected link of one with positive symptoms was verified, but the link of the other with negative symptoms was not.

Adult↗
PubMed2006

Effects of 5-HT on memory and the hippocampus: model and data.

5-Hydroxytryptamine (5-HT) transmission has been implicated in memory and in depression. Both 5-HT depletion and specific 5-HT agonists lower memory performance, while depression is also associated with memory deficits. The precise neuropharmacology and neural mechanisms underlying these effects are unknown. We used neural network simulations to elucidate the neuropharmacology and network mechanisms underlying 5-HT effects on memory. The model predicts that these effects are largely dependent on transmission over the 5-HT1A and 5-HT3 receptors, which regulate the selectivity of retrieval. It also predicts differential memory deficit profiles for 5-HT depletion and overactivation. The latter predictions were confirmed in studies with healthy and depressed participants undergoing acute tryptophan depletion or ipsipirone challenge. The results suggest that the memory impairments in depressed subjects may be related to 5-HT undertransmission, and support the notion that 5-HT1A agonists ameliorate memory deficits in depression.

Animals↗
PubMed2026

First-in-human use of recombinant IL-7 to potentiate antigen-specific T cell therapy: a single patient case study.

Clinical trials of adoptive cellular therapy demonstrate that a key characteristic associated with durable responses is in vivo expansion and persistence of transferred T cells. Strategies to develop a less differentiated, stem/memory population in the infusion product and peri-infusional regimens to promote the maintenance of desired T cell states following adoptive transfer would be desirable. Endogenous T cell therapy studies have routinely achieved memory T cells enriched for expression of interleukin (IL)-7 receptor; to eliminate the conventional requirement for immunosuppressive lymphodepletion and its attendant life-threatening toxicities, we performed the first-in-human use of IL-7 in combination with adoptively transferred antigen-specific memory CD8 T cells in a patient with refractory metastatic uveal melanoma. Single-cell immune repertoire profiling of serial peripheral blood sampling revealed substantial in vivo proliferation and expansion of a stem cell memory population in the endogenous T cell therapy product that achieved a >79% predominance of total circulating T cells by 3 weeks post-infusion in this non-lymphodepleted recipient. Although the patient's disease ultimately progressed, these findings demonstrate safety and proof of concept for an IL-7 treatment regimen for expansion of adoptively transferred T cells in vivo and induced memory differentiation in a heavily pretreated patient with refractory solid malignancy.

Humans↗
PubMed1994

CD57+ T lymphocytes are derived from CD57- precursors by differentiation occurring in late immune responses.

CD3+ T cells expressing the 110-kDa CD57 antigen are found in survivors of renal, cardiac and bone marrow transplants, in patients with acquired immune deficiency syndrome and in patients with rheumatoid arthritis. They are also present in normal individuals and expand upon ageing. They do not grow in culture and their role in the immune response is poorly understood. The expression of the various isoforms of the leukocyte common antigen (CD45) identifies a spectrum of differentiation in CD4+ and CD8+ T cells ranging from naive (CD45RA+CD45RBbrightCD45RO-) through early primed cells (CD45RA-RBbrightROdull) to highly differentiated memory cells which are CD45RA-RBdullRObright. CD45 isoforms expressed by CD57+ T cells showed distinct differences between CD4+ and CD8+ populations, but in each case indicated an advanced state of differentiation. The expression of T cell receptor V beta families was highly variable between individuals, but both CD57+ and CD57- cells show a full range of the specificities tested. V beta expression was more closely related within either the CD4+ or the CD8+ subsets, irrespective of CD57 expression, than between these subsets, suggesting a relationship between CD57+ and CD57- cells within the same T cell pool. This possibility was supported by experiments showing that CD3+CD57+ lymphocytes were similar to CD3+CD57- T cells in terms of the production of basic T cell cytokines [interleukin (IL)-2, IL-4, and interferon-gamma]. Furthermore, in vitro stimulation of CD3+CD57- T cells in secondary mixed leukocyte reaction or by co-culture with IL-2 and IL-4 induced the appearance of CD3+CD57+ cells with phenotypic and functional similarities to in vivo CD3+CD57+ cells. These data strongly suggest that the expression of CD57 is a differentiation event which occurs on CD57- T cells late in the immune response.

Antigens, CD↗
PubMed1985

Evaluation of accessory cell heterogeneity. III. Role of dendritic cells in the in vitro activation of the antibody response to soluble antigens.

Dendritic cells and macrophages obtained from spleen and peritoneal exudate were tested as accessory cells for the activation of lymphokine production by T cells, for supporting T-B cooperation and for the induction of antigen-specific T helper cells. Dendritic cells as well as macrophages were able to activate T cells for interleukin-2 secretion and functioned as accessory cells in T-B cooperation, but only macrophages induced T helper cells, which cooperate with B cells by a linked recognition interaction, to soluble antigens. Dendritic cell- and antigen-activated T cells also did not help B cells in the presence of Con A supernatants which contained various T cell- and B cell-stimulatory factors. The failure of dendritic cells to differentiate memory into functional T helper cells, but their efficient accessory cell function in T-B cooperation, where functional T helper cells are already present, can be best explained by a differential accessory cell requirement for T helper cell activation dependent on the differentiation stage of the T helper cell.

Animals↗
PubMed1993

Memory for gender-consistent and gender-inconsistent event sequences by twenty-five-month-old children.

Gender-schema theory predicts that, based on a rudimentary understanding of gender (e.g., self-labeling), children will invoke gender schemata in the processing of information. In older children, one indication of schematic processing is differential memory for schema-consistent versus schema-inconsistent material. Due to a lack of appropriate measures, evidence of very early use of gender schemata has been limited. In the present study, elicited imitation was used to assess 25-month-old girls' and boys' immediate and delayed recall of sequences depicting female-stereotyped, male-stereotyped, and gender-neutral activities. At immediate and delayed testing, girls showed equivalent levels of recall of all 3 sequence types. Boys showed superior recall of male- relative to female-stereotyped sequences; their recall of gender-neutral sequences was equivalent to that of male-stereotyped ones. Results indicate that, at least for boys, use of gender schemata is evident by 25 months of age. Possible explanations for the absence of a clear effect for girls are discussed.

Child Development↗
PubMedDate not supplied

Differential outcomes training facilitates memory in people with Korsakoff and Prader-Willi syndromes.

This article presents evidence that a teaching procedure called differential outcomes training enhances learning and memory. Differential outcomes training reinforces correct responses with outcomes that are unique and specific to the stimuli that are to be remembered. Teaching with this method enhances performance in people with Korsakoff syndrome and people with Prader-Willi syndrome, populations known to have learning and working memory deficits. This initial evidence that persons with learning and memory deficits benefit from differential outcomes training should encourage future work on the development of an intervention using this type of training to aide daily functioning by people with learning and memory impairments.

Cognition↗
PubMed2006

Brain activation patterns during memory of cognitive agency.

Agency is the awareness that one's own self is the agent or author of an action, a thought, or a feeling. The implicit memory that one's self was the originator of a cognitive event - the sense of cognitive agency - has not yet been fully explored in terms of relevant neural systems. In this functional magnetic resonance imaging (fMRI) study, we examined brain activation patterns differentiating memory for the source of previously self-generated vs. experimenter-presented word items from a sentence completion paradigm designed to be emotionally neutral and semantically constrained in content. Accurate memory for the source of self-generated vs. externally-presented word items resulted in activation of dorsal medial prefrontal cortex (mPFC) bilaterally, supporting an emerging body of work that indicates a key role for this region in self-referential processing. Our data extend the function of mPFC into the domain of memory and the accurate retrieval of the sense of cognitive agency under conditions where agency was encoded implicitly.

Adult↗
PubMed2002

Commonalities and differences in the working memory components underlying letter and category fluency tasks: a dual-task investigation.

This study used a dual-task interference paradigm to test the hypothesis that different subcomponents of working memory differentially contribute to performance on letter fluency and category fluency tasks. College students (N = 96) performed each type of verbal fluency task in isolation and concurrently with I of 3 secondary tasks. The secondary tasks were chosen for their putative involvement in different working memory subcomponents. Two subsystems of working memory, the phonological loop and the visuospatial sketchpad, were identified as important contributors to fluency performance, especially to performance on letter fluency and category fluency tasks, respectively. Moreover, the results also suggest that the executive function, mental set shifting, may be deployed to perform both letter fluency and category fluency tasks.

Adolescent↗
PubMed2004

Functional characterization of MHC class II-restricted CD8+CD4- and CD8-CD4- T cell responses to infection in CD4-/- mice.

Classical CD4(+) and CD8(+) T cells recognize Ag presented by MHC class II (MHCII) and MHC class I (MHCI), respectively. However, our results show that CD4(-/-) mice mount a strong, readily detectable CD8(+) T cell response to MHCII-restricted epitopes after a primary bacterial or viral infection. These MHCII-restricted CD8(+)CD4(-) T cells are more similar to classical CD8(+) T cells than to CD4(+) T cells in their expression of effector functions during a primary infection, yet they also differ from MHCI-restricted CD8(+) T cells by their inability to produce high levels of the cytolytic molecule granzyme B. After resolution of a primary infection, epitope-specific MHCII-restricted T cells in CD4(-/-) mice persist for a long period of time as memory T cells. Surprisingly, upon reinfection the secondary MHCII-restricted response in CD4(-/-) mice consists mainly of CD8(-)CD4(-) T cells. In contrast to CD8(+) T cells, MHCII-restricted CD8(-)CD4(-) T cells are capable of producing IL-2 in addition to IFN-gamma and thus appear to have attributes characteristic of CD4(+) T cells rather than CD8(+) T cells. Therefore, MHCII-restricted T cells in CD4(-/-) mice do not share all phenotypic and functional characteristics with MHCI-restricted CD8(+) T cells or with MHCII-restricted CD4(+) T cells, but, rather, adopt attributes from each of these subsets. These results have implications for understanding thymic T cell selection and for elucidating the mechanisms regulating the peripheral immune response and memory differentiation.

Animals↗
PubMed2005

Stepwise differentiation of CD4 memory T cells defined by expression of CCR7 and CD27.

To study the steps in the differentiation of human memory CD4 T cells, we characterized the functional and lineage relationships of three distinct memory CD4 subpopulations distinguished by their expression of the cysteine chemokine receptor CCR7 and the TNFR family member CD27. Using the combination of these phenotypic markers, three populations were defined: the CCR7+CD27+, the CCR7-CD27+, and the CCR7-CD27- population. In vitro stimulation led to a stepwise differentiation from naive to CCR7+CD27+ to CCR7-CD27+ to CCR7-CD27-. Telomere length in these subsets differed significantly (CCR7+CD27+ > CCR7-CD27+ > CCR7-CD27-), suggesting that these subsets constituted a differentiative pathway with progressive telomere shortening reflecting antecedent in vivo proliferation. The in vitro proliferative response of these populations declined, and their susceptibility to apoptosis increased progressively along this differentiation pathway. Cytokine secretion showed a differential functional capacity of these subsets. High production of IL-10 was only observed in CCR7+CD27+, whereas IFN-gamma was produced by CCR7-CD27+ and to a slightly lesser extent by CCR7-CD27- T cells. IL-4 secretion was predominantly conducted by CCR7-CD27- memory CD4 T cells. Thus, by using both CCR7 and CD27, distinct maturational stages of CD4 memory T cells with different functional activities were defined.

Adult↗
PubMed2003

The influence of cognitive reserve on memory following electroconvulsive therapy.

Cognitive reserve (CR) theory proposes that certain genetic and nonacquired variables, such as larger head size and greater neuronal density, and some life experiences, such as higher educational and occupational attainment, provide a buffer against brain dysfunction in the face of acquired central nervous system (CNS) dysfunction. This study examined CR in the pseudoexperimental paradigm of electroconvulsive therapy (ECT). Subjects included fifty (N = 50) depressed patients treated with bilateral ECT. Subjects were placed in high (n = 27) or low (n = 23) CR groups based on years of education and occupational attainment. At baseline, no significant differences were observed between the groups in the amount of information forgotten on a verbal memory measure (Randt stories) after a 30-minute delay. Following three ECT treatments, however, the high CR group forgot significantly less information after a 30-minute delay, as compared to the low CR group (p < 0.01). These data provide further support for CR theory and suggest that CR may be an underlying factor in differential memory loss in ECT.

Adult↗
PubMed1990

Regulated expression and binding of three VLA (beta 1) integrin receptors on T cells.

Regulated adhesion of T cells to extracellular matrix (ECM) proteins is likely to be essential in T cell migration. Constitutive binding of various other cell types to ECM components is mediated by members of the VLA (very late antigen) subfamily of integrins. We describe here the regulated binding of resting CD4+ human T cells to ECM through three VLA integrins: VLA-4 and VLA-5 binding to fibronectin (FN), and a novel pathway of VLA-6 binding to laminin (LN). Binding to ECM is regulated in two ways. First, unlike other VLA-mediated interactions, VLA binding activity of the T cells is rapidly and dramatically augmented with cell activation without change in level of expression of the VLA molecules. Second, binding is regulated with T-cell differentiation; memory T cells express three- to four-fold more VLA-4, VLA-5, and VLA-6 than do naive cells, and bind more efficiently through them to FN and LN.

Antigens, CD↗