Página 1 dos resultados de 907 itens digitais encontrados em 0.135 segundos

## Codificação incidental da ordem serial na memória de trabalho visuoespacial: evidências baseadas em uma tarefa de detecção da mudança; Incidental encoding of serial order in visuospatial working memory: evidence based on a change detection task

Santana, Jeanny Joana Rodrigues Alves de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Relevância na Pesquisa
45.8%
A memória para a ordem dos eventos em uma sequência está relacionada com muitos domínios cognitivos, como direcionar o comportamento a um objetivo, reconhecer uma ação e prever eventos do ambiente. A codificação da ordem serial tem sido, portanto, um tema polêmico a ser explicado pelos modelos de memória de trabalho visuoespacial. Neste estudo investigamos a codificação incidental da ordem serial de eventos em tarefas de reconhecimento de sequências, nas quais a dimensão relevante para a resposta poderia ser a aparência visual, a localização espacial ou a conjunção visuoespacial dos eventos. A tarefa exigia que os participantes (n=60) detectassem uma mudança em um dos estímulos da sequência e ignorassem mudanças na dimensão irrelevante: a ordem na qual os eventos eram apresentados. De maneira geral, o desempenho foi mais prejudicado nas sequências em que a ordem dos itens mudava. A comparação das três condições de memória (aparência visual, localização espacial e conjunção visuoespacial) revelou que houve melhor desempenho na tarefa espacial. Nesta condição, ocorreu uma interação entre os fatores mudança na dimensão relevante (localização espacial) e mudança na dimensão irrelevante (ordem serial). Estes resultados revelam que a ordem foi codificada de forma incidental com as informações relevantes para a tarefa. A diferença do efeito da mudança da dimensão irrelevante para os três tipos de sequências sugere que a ordem foi codificada em um estágio inicial do processamento de informações e...

## A função executiva de atualização de informações na memória de trabalho para a ordem serial de eventos visuais e espaciais; The executive function of updating information in working memory for the serial order of visual and spatial events

Santana, Jeanny Joana Rodrigues Alves de
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Relevância na Pesquisa
55.81%
No modelo dos multicomponentes da memória de trabalho o problema do armazenamento da ordem serial de eventos visuais e espaciais ainda é muito discutido. A literatura sugere que recursos do executivo central (o sistema de controle atencional da memória de trabalho) são utilizados para manter a representação da posição serial dos estímulos visuais e espaciais na memória. Mais precisamente, é proposto que a função executiva de atualização de informações esteja envolvida com este processo. Esta função promoveria a modificação contínua da representação mental conforme a entrada de novas informações no sistema cognitivo. Entretanto, não está esclarecido se ocorre uma dissociação visual e espacial no uso de recursos da função executiva de atualização de informações para o registro da ordem serial. O objetivo do presente estudo foi verificar o envolvimento da função executiva de atualização da informação na memória para a ordem de eventos visuais e espaciais. Os participantes foram estudantes universitários (n = 71) que realizaram as tarefas de memória delineadas segundo o paradigma de tarefas duplas. Neste procedimento as tarefas primárias de memória visual e espacial foram combinadas a tarefas secundárias executivas de tempo de reação de escolha (CRT) e tarefas que exigiam recursos de atualização da informação (tarefa de tempo de reação de escolha para um item anterior CRT-1). Na tarefa CRT o participante deveria julgar dois tons auditivos como sendo de alta ou baixa frequência. Na tarefa CRT-1 esta resposta deveria ser atrasada em um item...

## From expatriates’ information needs to information management in the expatriation cycle

Pinheiro, Mónica; Barrulas, Maria Joaquina
Fonte: Laboratório Nacional de Energia e Geologia Publicador: Laboratório Nacional de Energia e Geologia
Tipo: Conferência ou Objeto de Conferência
Relevância na Pesquisa
45.6%
Globalization has intensified the flow of companies’ top executives across borders. New information needs arise and are added to several other challenges faced by these executives when they move to a foreign country. Cultural differences of the host countries, and lack of local language skills preventing expatriates making sense of the social context and physical environment surrounding them, are among those challenges. This paper reports findings of a study aimed at identifying and understanding the role of information in top executives’ mobility process, during expatriation cycle. The study was carried out between 2003 and 2004, and covered half of the existing expatriates working for a Portuguese economic group of the financial sector, in three different country operations. The case study was the methodological approach chosen. To understand the information needs of expatriates, three embedded cases were considered, illustrating the economic group as a whole. The embedded cases corresponded to business operations in three different countries that had begun operating at different times (1997, 2000, and 2003). The choice of the countries accounted for: variety and diversity of the business operations abroad, their political importance and different stages of expatriates in the expatriation cycle. Several data collection methods were used...

## Electrophysiological indices of memory for temporal order in early childhood: implications for the development of recollection

Riggins, Tracy; Miller, Neely C.; Bauer, Patricia J.; Georgieff, Michael K.; Nelson, Charles A.
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
45.62%
The ability to recall contextual details associated with an event begins to develop in the first year of life, yet adult levels of recall are not reached until early adolescence. Dual-process models of memory suggest that the distinct retrieval process that supports the recall of such contextual information is recollection. In the present investigation, we used both behavioral and electrophysiological measures to assess the development of memory for contextual details, as indexed by memory for temporal order, in early childhood. Results revealed age-related improvements in memory for temporal order despite similar levels of memory for the individual items themselves. Furthermore, this pattern of recall was associated with specific components in the electrophysiological response. Consistent with electrophysiological research in adults, distributed, positive-going activity late in the waveform was associated with increases in recall of contextual details and the development of recollective processes.

## Distinct roles for dorsal CA3 and CA1 in memory for sequential nonspatial events

Farovik, Anja; Dupont, Laura M.; Eichenbaum, Howard
Fonte: Cold Spring Harbor Laboratory Press Publicador: Cold Spring Harbor Laboratory Press
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
45.66%
Previous studies have suggested that dorsal hippocampal areas CA3 and CA1 are both involved in representing sequences of events that compose unique episodes. However, it is uncertain whether the contribution of CA3 is restricted to spatial information, and it is unclear whether CA1 encodes order per se or contributes by an active maintenance of memories of sequential events. Here, we developed a new behavioral task that examines memory for the order of sequential nonspatial events presented as trial-unique odor pairings. When the interval between odors within a studied pair was brief (3 sec), bilateral dorsal CA3 lesions severely disrupted memory for their order, whereas dorsal CA1 lesions did not affect performance. However, when the inter-item interval was extended to 10 sec, CA1 lesions, as well as CA3 lesions, severely disrupted performance. These findings suggest that the role of CA3 in sequence memory is not limited to spatial information, but rather appears to be a fundamental property of CA3 function. In contrast, CA1 becomes involved when memories for events must be held or sequenced over long intervals. Thus, CA3 and CA1 are both involved in memory for sequential nonspatial events that compose unique experiences, and these areas play different roles that are distinguished by the duration of time that must be bridged between key events.

## The Effect of Arousal on the Emotional Memory Network Depends on Valence

Mickley Steinmetz, Katherine R.; Addis, Donna Rose; Kensinger, Elizabeth A.
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
45.63%
Some suggest that arousal is the essential element in order to engage the amygdala. However, the role of arousal in the larger emotional memory network may differ depending on the valence (positive, negative) of the to-be-remembered information. The goal of the current study was to determine the influence of arousal-based changes in amygdalar connectivity for positive and negative items. Participants were shown emotional and neutral pictures while they underwent a functional magnetic resonance imaging (fMRI) scan. The emotional pictures varied by valence (positive or negative), and arousal (high or low). Approximately 45 minutes later, outside of the scanner, participants took a surprise recognition test. Effective connectivity analysis examined how arousal affected successful encoding activity. For negative information, arousal increased the strength of amygdala connections to the inferior frontal gyrus and the middle occipital gyrus, while for positive information arousal decreased the strength of these amygdala efferents. Further, while the effect of arousal on memory for positive information was restricted to amygdalar efferents, arousal had a more widespread effect for negative items, enhancing connectivity between other nodes of the emotional memory network. These findings emphasize that the effect of arousal on the connectivity within the emotional memory network depends on item valence.

## “Distracters” Do Not Always Distract: Visual Working Memory for Angry Faces is Enhanced by Incidental Emotional Words

Jackson, Margaret C.; Linden, David E. J.; Raymond, Jane E.
Fonte: Frontiers Media S.A. Publicador: Frontiers Media S.A.
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.62%
We are often required to filter out distraction in order to focus on a primary task during which working memory (WM) is engaged. Previous research has shown that negative versus neutral distracters presented during a visual WM maintenance period significantly impair memory for neutral information. However, the contents of WM are often also emotional in nature. The question we address here is how incidental information might impact upon visual WM when both this and the memory items contain emotional information. We presented emotional versus neutral words during the maintenance interval of an emotional visual WM faces task. Participants encoded two angry or happy faces into WM, and several seconds into a 9 s maintenance period a negative, positive, or neutral word was flashed on the screen three times. A single neutral test face was presented for retrieval with a face identity that was either present or absent in the preceding study array. WM for angry face identities was significantly better when an emotional (negative or positive) versus neutral (or no) word was presented. In contrast, WM for happy face identities was not significantly affected by word valence. These findings suggest that the presence of emotion within an intervening stimulus boosts the emotional value of threat-related information maintained in visual WM and thus improves performance. In addition...

## Prefrontal and Medial Temporal Lobe Activity at Encoding Predicts Temporal Context Memory

Jenkins, Lucas J.; Ranganath, Charan
Fonte: Society for Neuroscience Publicador: Society for Neuroscience
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
45.66%
One of the defining features of episodic long-term memory is that it includes information about the temporal context in which an event occurred. Little is known about the regions that support the encoding of temporal information in the human brain, although previous work has suggested a role for the lateral prefrontal cortex (PFC) and medial temporal lobes (MTL). Here we used event-related fMRI to examine the relationship between activity at encoding and subsequent memory for temporal context. Participants were scanned while performing a serial order working memory task with pictures of common objects and were later tested for temporal memory at two different timescales. In the coarse temporal memory test, participants viewed one object from each trial and indicated approximately when during the course of the experiment it had appeared. In the fine temporal memory test, participants were shown the remaining objects from each trial and asked to recall the order in which they had been originally presented. Activity in the parahippocampal cortex predicted subsequent fine temporal accuracy, whereas coarse temporal accuracy was predicted by activity in several regions of the PFC, as well as in the hippocampus. Additional multivoxel pattern analyses revealed evidence implicating the rostrolateral PFC in the representation of time-varying contextual states in a manner similar to that proposed by computational theories of temporal context memory. These results highlight MTL and PFC contributions to temporal memory at the time of encoding and suggest a particular role for the rostrolateral PFC in encoding coarse temporal context.

## The Representation of Order Information in Auditory-Verbal Short-Term Memory

Kalm, Kristjan; Norris, Dennis
Fonte: Society for Neuroscience Publicador: Society for Neuroscience
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.64%
Here we investigate how order information is represented in auditory-verbal short-term memory (STM). We used fMRI and a serial recall task to dissociate neural activity patterns representing the phonological properties of the items stored in STM from the patterns representing their order. For this purpose, we analyzed fMRI activity patterns elicited by different item sets and different orderings of those items. These fMRI activity patterns were compared with the predictions made by positional and chaining models of serial order. The positional models encode associations between items and their positions in a sequence, whereas the chaining models encode associations between successive items and retain no position information. We show that a set of brain areas in the postero-dorsal stream of auditory processing store associations between items and order as predicted by a positional model. The chaining model of order representation generates a different pattern similarity prediction, which was shown to be inconsistent with the fMRI data. Our results thus favor a neural model of order representation that stores item codes, position codes, and the mapping between them. This study provides the first fMRI evidence for a specific model of order representation in the human brain.

## Temporal Memory Is Shaped by Encoding Stability and Intervening Item Reactivation

DuBrow, Sarah; Davachi, Lila
Fonte: Society for Neuroscience Publicador: Society for Neuroscience
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
55.68%
Making sense of previous experience requires remembering the order in which events unfolded in time. Prior work has implicated the hippocampus and medial temporal lobe cortex in memory for temporal information associated with individual episodes. However, the processes involved in encoding and retrieving temporal information across extended sequences is relatively poorly understood. Here we used fMRI during the encoding and retrieval of extended sequences to test specific predictions about the type of information used to resolve temporal order and the role of the hippocampus in this process. Participants studied sequences of images of celebrity faces and common objects followed by a recency discrimination test. The main conditions of interest were pairs of items that had been presented with three intervening items, half of which included an intervening category shift. During encoding, hippocampal pattern similarity across intervening items was associated with subsequent successful order memory. To test for evidence of associative retrieval, we trained a classifier to discriminate encoding patterns associated with faces versus objects and applied the classifier on fMRI patterns during recency discrimination. We found evidence that the category content of intervening items was reactivated during recency judgments...

## Time, Space and Memory for Order

Fischer-Baum, Simon; Benjamin, Aaron S.
Tipo: Artigo de Revista Científica
ENG
Relevância na Pesquisa
55.6%
Information about the order of items in a sequence can be conveyed either spatially or temporally. The current investigation examines whether these different modes of presentation map onto compatible mental representations of serial order. We examined this issue in three immediate serial recall experiments, in which participants recalled lists of letters in the temporal order they appeared. Each letter in a to-be-remembered sequence was presented in a unique spatial position, with the order of these spatial positions progressing from either left-to-right or from right-to-left. In this way, the visually presented lists contained both temporal and spatial order information. Recall of temporal order information was more accurate with congruent spatial order information – when the letters progressed from left-to-right, following the typical reading direction of English – compared to when the spatial order information was incongruent. These results suggest compatible representations of serial order when sequences are conveyed spatially and temporally.

## Adaptação transcultural e propriedades psicométricas do subteste Visual Reproduction (Reprodução Visual I e II) da Wechsler Memory Scale - Fourth Edition (WMS-IV), (Escalas de Memória de Wechsler) para uma população do Brasil; Transcultural Adaptation of the subtest Visual Reproduction I and II of the Wechsler Memory Scale - IV (WMS-IV) (Wechsler Memory Scale) to one culture from Brazil.

Spedo, Carina Tellaroli
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Dissertação de Mestrado Formato: application/pdf
Relevância na Pesquisa
45.67%

## Implications of differences of echoic and iconic memory for the design of multimodal displays

Glaser, Daniel Shields
Tipo: Thesis; Text Formato: 169 p.; application/pdf
ENG
Relevância na Pesquisa
55.75%
It has been well documented that dual-task performance is more accurate when each task is based on a different sensory modality. It is also well documented that the memory for each sense has unequal durations, particularly visual (iconic) and auditory (echoic) sensory memory. In this dissertation I address whether differences in sensory memory (e.g. iconic vs. echoic) duration have implications for the design of a multimodal display. Since echoic memory persists for seconds in contrast to iconic memory which persists only for milliseconds, one of my hypotheses was that in a visual-auditory dual task condition, performance will be better if the visual task is completed before the auditory task than vice versa. In Experiment 1 I investigated whether the ability to recall multi-modal stimuli is affected by recall order, with each mode being responded to separately. In Experiment 2, I investigated the effects of stimulus order and recall order on the ability to recall information from a multi-modal presentation. In Experiment 3 I investigated the effect of presentation order using a more realistic task. In Experiment 4 I investigated whether manipulating the presentation order of stimuli of different modalities improves humans' ability to combine the information from the two modalities in order to make decision based on pre-learned rules. As hypothesized...

## INFORMATION PROCESSING CORRELATES OF MEMORY SPAN: AN INDIVIDUAL DIFFERENCES APPROACH

Tipo: Thesis; Text Formato: application/pdf
ENG
Relevância na Pesquisa
45.65%
Three processes, item identification speed, susceptibility to proactive interference, and memory for order, identified for their potential as sources of memory span differences, were the subjects of the present investigation. A fourth variable, item memory, was included as the experimental complement of order memory (Healy, 1974). Performance on each of these four variables and memory span was obtained for 90 college-aged subjects. Moderate to high reliability was evidenced for each of the tasks. Memory span correlated significantly with each source of differences examined. Additionally, using a multiple regression analysis, each variable was shown to contribute significant, independent variance in the joint prediction of memory span. Subjects' scores on the four predictor variables were used in a cluster analysis which identified four subsets of individuals. An ANOVA determined that the four groups differed in their mean memory span scores. The differences among these groups were examined using a multiple discriminant analysis. The groups were found to differ along three dimensions. Evidence from these analyses indicates that an individual's memory span is the result of complex processes involving, at least, components of item identification speed...

## Young Children's Memory for the Times of Personal Past Events

Pathman, Thanujeni; Larkina, Marina; Burch, Melissa; Bauer, Patricia J.
Tipo: Artigo de Revista Científica
EN
Relevância na Pesquisa
45.59%
Remembering the temporal information associated with personal past events is critical for autobiographical memory, yet we know relatively little about the development of this capacity. In the present research, we investigated temporal memory for naturally occurring personal events in 4-, 6-, and 8-year-old children. Parents recorded unique events in which their children participated during a 4-month period. At test, children made relative recency judgments and estimated the time of each event using conventional time-scales (time of day, day of week, month of year, and season). Children also were asked to provide justifications for their time-scale judgments. Six- and 8-year-olds, but not 4-year-olds, accurately judged the order of two distinct events. There were age-related improvements in children's estimation of the time of events using conventional time-scales. Older children provided more justifications for their time-scale judgments compared to younger children. Relations between correct responding on the time-scale judgments and provision of meaningful justifications suggest that children may use that information to reconstruct the times associated with past events. The findings can be used to chart a developmental trajectory of performance in temporal memory for personal past events...

## Statistical Signatures of Structural Organization: The case of long memory in renewal processes

Marzen, Sarah E.; Crutchfield, James P.
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
45.72%
Identifying and quantifying memory are often critical steps in developing a mechanistic understanding of stochastic processes. These are particularly challenging and necessary when exploring processes that exhibit long-range correlations. The most common signatures employed rely on second-order temporal statistics and lead, for example, to identifying long memory in processes with power-law autocorrelation function and Hurst exponent greater than $1/2$. However, most stochastic processes hide their memory in higher-order temporal correlations. Information measures---specifically, divergences in the mutual information between a process' past and future (excess entropy) and minimal predictive memory stored in a process' causal states (statistical complexity)---provide a different way to identify long memory in processes with higher-order temporal correlations. However, there are no ergodic stationary processes with infinite excess entropy for which information measures have been compared to autocorrelation functions and Hurst exponents. Here, we show that fractal renewal processes---those with interevent distribution tails $\propto t^{-\alpha}$---exhibit long memory via a phase transition at $\alpha = 1$. Excess entropy diverges only there and statistical complexity diverges there and for all $\alpha < 1$. When these processes do have power-law autocorrelation function and Hurst exponent greater than $1/2$...

## Higher BMI is Associated with Episodic Memory Deficits in Young Adults; BMI and Episodic Memory; Episodic Memory Deficits in Obesity

Cheke, Lucy G.; Simons, Jon S.; Clayton, Nicola S.
Fonte: Taylor & Francis Publicador: Taylor & Francis
Tipo: Article; published version
EN
Relevância na Pesquisa
45.63%
This is the final version of the article. It first appeared from Taylor & Francis via http://dx.doi.org/10.1080/17470218.2015.1099163; Obesity has become an international health crisis. There is accumulating evidence that excess bodyweight is associated with changes to the structure and function of the brain and with a number of cognitive deficits. In particular, research suggests that obesity is associated with hippocampal and frontal lobe dysfunction, which would be predicted to impact memory. However evidence for such memory impairment is currently limited. We hypothesised that higher BMI would be associated with reduced performance on a test of episodic memory that assesses not only content, but also context and feature integration. 50 participants aged 18-35, with BMIs ranging from 18 to 51, were tested on a novel what-where-when style episodic memory test: The ?Treasure-Hunt Task?. This test requires recollection of object, location, and temporal order information within the same paradigm, as well as testing the ability to integrate these features into a single event recollection. Higher BMI was associated with significantly lower performance on the What-Where-When memory task and all individual elements: object identification...

## The Effect of Prioritization in Information Processing

Park, Hyun-Young
Relevância na Pesquisa
55.74%
Steven Benjamin Most; When listening to messages from the mass media, we may find that certain facts grab our attention ??? perhaps because we find them especially relevant. It is likely that we will remember these facts, but how does their attention-grabbing nature impact our memory for other information contained within the same broadcast? Do we just forget this other information? Because we are surrounded by overwhelming amounts of information, we tend to select and prioritize information that we consider to be important. Notably, visual working memory studies have shown that of the consequences such prioritization on processing of other information can be different according to the situation. Given this, our study examined how people???s information prioritization affects the memory of other unselected information. We asked people to listen to a passage about a fictional man, ???Jack,??? in order to decide whether to bet on him or against him in the first round of a tennis tournament. For half of the participants, this passage never contained any information relevant to their decision (that is, no information about tennis). For the other half of participants, a single piece of tennis-relevant information appeared midway through the passage. We compared the memory of people who heard only task-irrelevant statements with the memory of people who heard the one task-relevant word in the middle of the statements. Results revealed that after people heard the task relevant word...

## Putting some order in person memory: memory for (serial) order in impression formation

Costa, Rui S.
Fonte: Instituto Universitário de Lisboa Publicador: Instituto Universitário de Lisboa