Serial position effects in graphemic buffer impairment: An insight into components of orthographic working memory

2004 ◽

Vol 16 (1) ◽

pp. 40-52 ◽

Cited By ~ 21

Author(s):

Edward J. Golob ◽

Arnold Starr

Keyword(s):

Working Memory ◽

Serial Position ◽

Memory Retrieval ◽

Memory Load ◽

Memory Task ◽

Event Related Potentials ◽

Control Task ◽

Position Effects ◽

Serial Position Effects ◽

Related Potentials

It is established that recall of an item from a list of sequentially presented items is sensitive to the item's position in the memorized list. However, little is known about the brain mechanisms that mediate these serial position effects. Studies of working memory retrieval using event-related potentials report amplitude reductions during retrieval (auditory cortical N100, neocortical late positive wave [LPW]) as memory load increases. We tested the hypothesis that N100 and LPW amplitudes to probes are also affected by serial position. Eventrelated potentials were recorded from subjects performing an auditory working memory task. A set of one or five digits was memorized, then subjects classified a probe digit as either present or absent from the memory set. A control task was also given. Amplitudes of the N100 and LPW were reduced in the 5-item versus the 1-item set. In the 5-item set N100 amplitude was significantly larger for the initial (1st) serial position, relative to Positions 2–5, while linear increases in LPW amplitude were seen across serial positions (5th > 1st position). A control task without memorization showed no N100 or LPW amplitude changes with set size or serial position. The findings reveal that the N100 and LPW are influenced differently by serial position during working memory retrieval: N100 shows a primacy effect and LPW demonstrates a recency effect. The results suggest that primacy and recency effects may be mediated by different brain regions at different times during memory retrieval.

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Distinct role of flexible and stable encoding in sequential working memory

10.1101/525220 ◽

2019 ◽

Author(s):

Hyeonsu Lee ◽

Woochul Choi ◽

Youngjin Park ◽

Se-Bum Paik

Keyword(s):

Working Memory ◽

Serial Position ◽

Model Simulation ◽

Serial Position Effect ◽

Memory Performance ◽

Position Effect ◽

Sensory Information ◽

Position Effects ◽

Serial Position Effects ◽

Precise Analysis

AbstractThe serial-position effect in working memory is considered important for studying how a sequence of sensory information can be retained and manipulated simultaneously in neural memory circuits. Here, via a precise analysis of the primacy and recency effects in human psychophysical experiments, we propose that stable and flexible coding take distinct roles of retaining and updating information in working memory, and that their combination induces serial-position effects spontaneously. We found that stable encoding retains memory to induce the primacy effect, while flexible encoding used for learning new inputs induces the recency effect. A model simulation based on human data, confirmed that a neural network with both flexible and stable synapses could reproduce the major characteristics of serial-position effects. Our new prediction, that the control of resource allocation by flexible-stable coding balance can modulate memory performance in sequence-specific manner, was supported by pre-cued memory performance data in humans.

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Impact of Comorbid Depression on Serial Position Effects in Alzheimer’s Disease

GeroPsych ◽

10.1024/1662-9647/a000115 ◽

2014 ◽

Vol 27 (4) ◽

pp. 161-169 ◽

Cited By ~ 1

Author(s):

Nienke A. Hofrichter ◽

Sandra Dick ◽

Thomas G. Riemer ◽

Carsten Schleussner ◽

Monique Goerke ◽

...

Keyword(s):

Alzheimer’S Disease ◽

Alzheimer's Disease ◽

Serial Position ◽

Episodic Memory ◽

Memory Performance ◽

Memory Function ◽

Word List ◽

Position Effects ◽

Serial Position Effects ◽

List Memory

Hippocampal dysfunction and deficits in episodic memory have been reported for both Alzheimer’s disease (AD) and major depressive disorder (MDD). Primacy performance has been associated with hippocampus-dependent episodic memory, while recency may reflect working memory performance. In this study, serial position profiles were examined in a total of 73 patients with MDD, AD, both AD and MDD, and healthy controls (HC) by means of CERAD-NP word list memory. Primacy performance was most impaired in AD with comorbid MDD, followed by AD, MDD, and HC. Recency performance, on the other hand, was comparable across groups. These findings indicate that primacy in AD is impaired in the presence of comorbid MDD, suggesting additive performance decrements in this specific episodic memory function.

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