Search results for "Memory."
showing 10 items of 1949 documents
Exploring the switching of the focus of attention within working memory: A combined event-related potential and behavioral study.
2018
Abstract Working memory enables humans to maintain selected information for cognitive processes and ensures instant access to the memorized contents. Theories suggest that switching the focus of attention between items within working memory realizes the access. This is reflected in object-switching costs in response times when the item for the task processing is to be changed. Another correlate of attentional allocation in working memory is the P3a-component of the human event-related potential. The aim of this study was to demonstrate that switching of attention within working memory is a separable processing step. Participants completed a cued memory-updating task in which they were instr…
More on magnitude of priming in implicit memory tasks.
2002
The effects of word frequency, length of the word, and type of word Fragment in a fragment-completion test were investigated with 57 undergraduate students, 19–22 years. Priming with better performance on studied than on nonstudied words in this task was greater for low frequency words than for high frequency words and greater for fragments without the first letter than for fragments with the first letter. It was inferred that characteristics of fragments should be considered in any implicit memory task when the magnitude of priming is of interest. In general, word fragment-completion processes appear to be based on sources of information available in visual identification tasks.
Identifying musical pieces from fMRI data using encoding and decoding models.
2018
AbstractEncoding models can reveal and decode neural representations in the visual and semantic domains. However, a thorough understanding of how distributed information in auditory cortices and temporal evolution of music contribute to model performance is still lacking in the musical domain. We measured fMRI responses during naturalistic music listening and constructed a two-stage approach that first mapped musical features in auditory cortices and then decoded novel musical pieces. We then probed the influence of stimuli duration (number of time points) and spatial extent (number of voxels) on decoding accuracy. Our approach revealed a linear increase in accuracy with duration and a poin…
Does the Coordination of Verbal and Motor Information Explain the Development of Counting in Children?
2001
Counting is often considered to be the coordination of two actions: saying the number-words and pointing to each object. We report three experiments to test the hypothesis that this coordination requires the use of the central executive (A. D. Baddeley, 1990), and that the cost of coordination decreases with age. Participants were 5- and 9-year-old children and adults. At all ages tested, the manipulation of the difficulty of each component affected counting performance but did not make coordination more difficult. These results suggest that, at least from the age 5, counting is a procedure in which the control of coordination is not attention demanding.
Implicit memory functioning in schizophrenia: Explaining inconsistent findings of word stem completion tasks
2014
The definitive implicit memory profile of schizophrenia is yet to be clarified. Methodological differences between studies could be the reason for the inconsistent findings reported. In this study, we have examined implicit memory functioning using a word stem completion task. In addition, we have addressed methodological issues related with lexical and perceptual stimuli characteristics, and with the strategy used to calculate priming scores. Our data show similar performance values in schizophrenic patients and healthy controls. Furthermore, we have not detected significant differences in priming between the two groups, even when this parameter was calculated using three different procedu…
Perceptual priming in schizophrenia evaluated by word fragment and word stem completion
2011
Implicit memory seems to be preserved in schizophrenia as a whole, but dissociations between conceptual and perceptual tasks and between accuracy and reaction time measures have appeared. The present research has revealed some methodological limitations in many studies to date that are focused on the study of perceptual implicit memory in schizophrenic patients using accuracy measures. The review of these studies revealed that limitations are related to an inadequate definition of performance and priming measures, a lack of control over the characteristics of the stimuli, and the absence of information on the experimental procedures used in data collection. Moreover, the task used in these …
Confabulation: damage to a specific inferior medial prefrontal system
2008
Confabulation, the pathological production of false memories, occurs following a variety of aetiologies involving the frontal lobes, and is frequently held to be underpinned by combined memory and executive deficits. However, the critical frontal regions and specific cognitive deficits involved are unclear. Studies in amnesic patients have associated confabulation with damage to the orbital and ventromedial prefrontal cortices. However, neuroimaging studies have associated memory-control processes which are assumed to underlie confabulation with the right lateral prefrontal cortex. We used a confabulation battery to investigate the occurrence and localisation of confabulation in an unselect…
Unconscious response priming during continuous flash suppression.
2017
Continuous flash suppression (CFS) has become a popular tool for studying unconscious processing, but the level at which unconscious processing of visual stimuli occurs under CFS is not clear. Response priming is a robust and well-understood phenomenon, in which the prime stimulus facilitates overt responses to targets if the prime and target are associated with the same response. We used CFS to study unconscious response priming of shape: arrows with left or right orientation served as primes and targets. The prime was presented near the limen of consciousness and each trial was followed by subjective rating of visibility and a forced-choice response concerning the orientation of the prime…
Continuity and discontinuity in memory for threat.
2016
Using a paradigm that allows a quasi-continuous tracking of memory performance over time, two experiments were designed to test the hypotheses that (a) persons with a cognitively avoidant style of coping with threat manifest a dissociation between (intact) short-term and (reduced) long-term retrieval of aversive information and (b) persons with a vigilant coping style recall aversive information particularly well after long retention intervals, provided they are free to think about aversive events. Study 1 (N = 75) showed that avoiders manifest a poor memory for aversive pictures after long retention intervals only. Study 2 (N = 95) replicated this finding. In addition, manipulation of the …
Taking both sides: do unilateral anterior temporal lobe lesions disrupt semantic memory?
2010
The most selective disorder of central conceptual knowledge arises in semantic dementia, a degenerative condition associated with bilateral atrophy of the inferior and polar regions of the temporal lobes. Likewise, semantic impairment in both herpes simplex virus encephalitis and Alzheimer's disease is typically associated with bilateral, anterior temporal pathology. These findings suggest that conceptual representations are supported via an interconnected, bilateral, anterior temporal network and that it may take damage to both sides to produce an unequivocal deficit of central semantic memory. We tested and supported this hypothesis by investigating a case series of 20 patients with unila…