oalib
Search Results: 1 - 10 of 100 matches for " "
All listed articles are free for downloading (OA Articles)
Page 1 /100
Display every page Item
THE HIERARCHICAL STRUCTURE OF FRONTAL LOBE IN MEDIATING THE PERCEPTUAL LEVEL INHIBITION AND WORKING MEMORY LEVEL INHIBITION
额叶皮层内知觉干扰与工作记忆干扰引起的抑制

Luo Jing,Kazuhisa Niki,Ding Zhiguang,Luo Yuejia,
罗劲
,仁木和久,丁之光,罗跃嘉

心理学报 , 2003,
Abstract: As one of the most important components in human's high level cognitive process and one of the most basic functions of the frontal lobe, inhibition refers to the cognitive ability to suppress the irrelevant or interfering sensory input, motor output, or internal process. Recent cognitive neuroscience studies showed that different frontal regions are sensitive to different interferences and inhibitions. Yet, it is still unclear how the different kinds of inhibitory functions are hierarchically organized in the frontal regions. In this event-related fMRI study, we disassociated the frontal regions that were sensitive to the inhibition caused by perceptual interference and those were sensitive to the inhibition caused by working memory interference. Results proved that the hierarchical structure of the frontal lobe in mediating different kinds of inhibitory functions: posterior regions were responsive to the perceptual competition and inhibition, whereas anterior regions responded to the working memory ones.
Age-related changes to the neural correlates of working memory which emerge after midlife  [PDF]
Helen N. Macpherson,David J. White,Con Stough
Frontiers in Aging Neuroscience , 2014, DOI: 10.3389/fnagi.2014.00070
Abstract: Previous research has indicated that the neural processes which underlie working memory change with age. Both age-related increases and decreases to cortical activity have been reported. This study investigated which stages of working memory are most vulnerable to age-related changes after midlife. To do this we examined age-differences in the 13Hz steady state visually evoked potential (SSVEP) associated with a spatial working memory delayed response task. Participants were 130 healthy adults separated into a midlife (40 to 60 years) and an older group (61 to 82 years). Relative to the midlife group, older adults demonstrated greater bilateral frontal activity during encoding and this pattern of activity was related to better working memory performance. In contrast, evidence of age-related under activation was identified over left frontal regions during retrieval. Findings from this study suggest that after midlife, under-activation of frontal regions during retrieval contributes to age-related decline in working memory performance.
Proactive Interference Does Not Meaningfully Distort Visual Working Memory Capacity Estimates in the Canonical Change Detection Task  [PDF]
Po-Han Lin,Steven J. Luck
Frontiers in Psychology , 2012, DOI: 10.3389/fpsyg.2012.00042
Abstract: The change detection task has become a standard method for estimating the storage capacity of visual working memory. Most researchers assume that this task isolates the properties of an active short-term storage system that can be dissociated from long-term memory systems. However, long-term memory storage may influence performance on this task. In particular, memory traces from previous trials may create proactive interference that sometimes leads to errors, thereby reducing estimated capacity. Consequently, the capacity of visual working memory may be higher than is usually thought, and correlations between capacity and other measures of cognition may reflect individual differences in proactive interference rather than individual differences in the capacity of the short-term storage system. Indeed, previous research has shown that change detection performance can be influenced by proactive interference under some conditions. The purpose of the present study was to determine whether the canonical version of the change detection task – in which the to-be-remembered information consists of simple, briefly presented features – is influenced by proactive interference. Two experiments were conducted using methods that ordinarily produce substantial evidence of proactive interference, but no proactive interference was observed. Thus, the canonical version of the change detection task can be used to assess visual working memory capacity with no meaningful influence of proactive interference.
Working Memory Training Using Mental Calculation Impacts Regional Gray Matter of the Frontal and Parietal Regions  [PDF]
Hikaru Takeuchi, Yasuyuki Taki, Yuko Sassa, Hiroshi Hashizume, Atsushi Sekiguchi, Ai Fukushima, Ryuta Kawashima
PLOS ONE , 2011, DOI: 10.1371/journal.pone.0023175
Abstract: Training working memory (WM) improves performance on untrained cognitive tasks and alters functional activity. However, WM training's effects on gray matter morphology and a wide range of cognitive tasks are still unknown. We investigated this issue using voxel-based morphometry (VBM), various psychological measures, such as non-trained WM tasks and a creativity task, and intensive adaptive training of WM using mental calculations (IATWMMC), all of which are typical WM tasks. IATWMMC was associated with reduced regional gray matter volume in the bilateral fronto-parietal regions and the left superior temporal gyrus. It improved verbal letter span and complex arithmetic ability, but deteriorated creativity. These results confirm the training-induced plasticity in psychological mechanisms and the plasticity of gray matter structures in regions that have been assumed to be under strong genetic control.
Age-Related Change in Visual Working Memory: A Study of 55,753 Participants Aged 8–75  [PDF]
James R. Brockmole
Frontiers in Psychology , 2013, DOI: 10.3389/fpsyg.2013.00012
Abstract: Visual working memory (VWM) abilities of 55,753 individuals between the ages of 8 and 75 were assessed to provide the most fine-grain analysis of age-related change in VWM to date. Results showed that VWM changes throughout the lifespan, peaking at age 20. A sharp linear decline follows that is so severe that by age 55, adults possess poorer immediate visual memory than 8 and 9 year olds. These developmental changes were largely explained by changing VWM capacity coupled with small short-term visual feature binding difficulties among children and older adults.
Resting-State Neuronal Oscillatory Correlates of Working Memory Performance  [PDF]
David Heister, Mithun Diwakar, Sharon Nichols, Ashley Robb, Anne Marie Angeles, Omer Tal, Deborah L. Harrington, Tao Song, Roland R. Lee, Mingxiong Huang
PLOS ONE , 2013, DOI: 10.1371/journal.pone.0066820
Abstract: Purpose Working memory (WM) represents the brain’s ability to maintain information in a readily available state for short periods of time. This study examines the resting-state cortical activity patterns that are most associated with performance on a difficult working-memory task. Methods Magnetoencephalographic (MEG) band-passed (delta/theta (1–7 Hz), alpha (8–13 Hz), beta (14–30 Hz)) and sensor based regional power was collected in a population of adult men (18–28 yrs, n = 24) in both an eyes-closed and eyes-open resting state. The normalized power within each resting state condition as well as the normalized change in power between eyes closed and open (zECO) were correlated with performance on a WM task. The regional and band-limited measures that were most associated with performance were then combined using singular value decomposition (SVD) to determine the degree to which zECO power was associated with performance on the three-back verbal WM task. Results Changes in power from eyes closed to open revealed a significant decrease in power in all band-widths that was most pronounced in the posterior brain regions (delta/theta band). zECO right posterior frontal and parietal cortex delta/theta power were found to be inversely correlated with three-back working memory performance. The SVD evaluation of the most correlated zECO metrics then provided a singular measure that was highly correlated with three-back performance (r = ?0.73, p<0.0001). Conclusion Our results indicate that there is an association between WM performance and changes in resting-state power (right posterior frontal and parietal delta/theta power). Moreover, an SVD of the most associated zECO measures produces a composite resting-state metric of regional neural oscillatory power that has an improved association with WM performance. To our knowledge, this is the first investigation that has found that changes in resting state electromagnetic neural patterns are highly associated with verbal working memory performance.
Change of cholinergic transmission and memory deficiency induced by injection of β-amyloid protein into NBM of rats
Xiaofeng Ma,Weiling Ye,Zhentong Mei
Science China Life Sciences , 2001, DOI: 10.1007/BF02879611
Abstract: The change of cholinergic transmission of β-amyloid protein (β-AP) treated rats was studied by intracerebral microdialysis sampling combined with HPLC analysis. β-AP1-40 was injected into nucleus basalis magnocellularis (NBM). Passive avoidance response test (step-down test) and delayed alternation task were used for memory testing. The impairment of memory after injection of β-AP1-40 into NBM exhibited mainly the deficiency of short-term working memory. One week after injection of β-AP1-40 the release of acetylcholine (ACh) from frontal cortex of freely-moving rats decreased significantly, and the response of cholinergic nerve ending to the action of high [K+] solution was rather weak. In control animals the percentage of increase of AChrelease during behavioral performance was 57%, while in β-AP1-40-treated rats it was 34%. The temporary increase of the ACh-release of the rat put into a new place was also significantly diminished in β-AP1-40 -treated rats. The results show that the injection of β-AP1-40 into NBM impairs the cholinergic transmission in frontal cortex, and the impairment of cholinergic transmission may be the main cause of the deficit of working memory.
Change of cholinergic transmission and memory deficiency induced by injection of ?-amyloid protein into NBM of rats

MA Xiaofeng,YE Weiling,MEI Zhentong,

中国科学C辑(英文版) , 2001,
Abstract: The change of cholinergic transmission of β-amyloid protein (β-AP) treated rats was studied by intracerebral microdialysis sampling combined with HPLC analysis. β-AP1-40 was injected into nucleus basalis magnocellularis (NBM). Passive avoidance response test (step-down test) and delayed alternation task were used for memory testing. The impairment of memory after injection of β-AP1-40 into NBM exhibited mainly the deficiency of short-term working memory. One week after injection of β-AP1-40 the release of acetylcholine (ACh) from frontal cortex of freely-moving rats decreased significantly, and the response of cholinergic nerve ending to the action of high K+] solution was rather weak. In control animals the percentage of increase of AChrelease during behavioral performance was 57%, while in β-AP1-40-treated rats it was 34%. The temporary increase of the ACh-release of the rat put into a new place was also significantly diminished in β-AP1-40 -treated rats. The results show that the injection of β-AP1-40 into NBM impairs the cholinergic transmission in frontal cortex, and the impairment of cholinergic transmission may be the main cause of the deficit of working memory.
The interface between priming memory and the working memory  [PDF]
Graeme E. Smith
PeerJ , 2015, DOI: 10.7287/peerj.preprints.41v1
Abstract: There is an interface between priming memory and working memory that acts to limit the amount of data in working memory, and also allows priming memory to be actively maintained so that memories stay intact while they are in working memory. This interface converts from functional clusters to chunks automatically as part of the transfer from priming to working memory. As a result, memories in working memory can be rehearsed in order to actively maintain them. This represents more than a change in state, it represents a radical change in the way memories are accessed. Priming memory without this stage can only be extended it cannot be refreshed and so there is a limit of about 3 seconds to how long it will last before it begins to degrade. With priming, an actively maintained and refreshed signal can last almost indefinitely.
Detailed Sensory Memory, Sloppy Working Memory  [PDF]
Ilja G. Sligte,Annelinde R. E. Vandenbroucke,H. Steven Scholte,Victor A. F. Lamme
Frontiers in Psychology , 2010, DOI: 10.3389/fpsyg.2010.00175
Abstract: Visual short-term memory (VSTM) enables us to actively maintain information in mind for a brief period of time after stimulus disappearance. According to recent studies, VSTM consists of three stages – iconic memory, fragile VSTM, and visual working memory – with increasingly stricter capacity limits and progressively longer lifetimes. Still, the resolution (or amount of visual detail) of each VSTM stage has remained unexplored and we test this in the present study. We presented people with a change detection task that measures the capacity of all three forms of VSTM, and we added an identification display after each change trial that required people to identify the “pre-change” object. Accurate change detection plus pre-change identification requires subjects to have a high-resolution representation of the “pre-change” object, whereas change detection or identification only can be based on the hunch that something has changed, without exactly knowing what was presented before. We observed that people maintained 6.1 objects in iconic memory, 4.6 objects in fragile VSTM, and 2.1 objects in visual working memory. Moreover, when people detected the change, they could also identify the pre-change object on 88% of the iconic memory trials, on 71% of the fragile VSTM trials and merely on 53% of the visual working memory trials. This suggests that people maintain many high-resolution representations in iconic memory and fragile VSTM, but only one high-resolution object representation in visual working memory.
Page 1 /100
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.