Feature Fusion Reveals Slow and Fast Visual Memories

Although the visual system can achieve a coarse classification of its inputs in a relatively short time, the synthesis of qualia-rich and detailed percepts can take substantially more time. If these prolonged computations were to take place in a retinotopic space, moving objects would generate extensive smear. However, under normal viewing conditions, moving objects appear relatively sharp and clear, suggesting that a substantial part of visual short-term memory takes place at a nonretinotopic locus. By using a retinotopic feature fusion and a nonretinotopic feature attribution paradigm, we provide evidence for a relatively fast retinotopic buffer and a substantially slower nonretinotopic memory. We present a simple model that can account for the dynamics of these complementary memory processes. Taken together, our results indicate that the visual system can accomplish temporal integration of information while avoiding smear by breaking off sensory memory into fast and slow components that are implemented in retinotopic and nonretinotopic loci, respectively.

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Using AI-Based Classification Techniques to Process EEG Data Collected during the Visual Short-Term Memory Assessment

Journal of Sensors ◽

10.1155/2020/8767865 ◽

2020 ◽

Vol 2020 ◽

pp. 1-12 ◽

Cited By ~ 1

Author(s):

Milos Antonijevic ◽

Miodrag Zivkovic ◽

Sladjana Arsic ◽

Aleksandar Jevremovic

Keyword(s):

Visual Information ◽

Short Term Memory ◽

Support Vector ◽

Short Term ◽

Term Memory ◽

Memory Assessment ◽

Visual Short Term Memory ◽

Eeg Data ◽

Short Period

Visual short-term memory (VSTM) is defined as the ability to remember a small amount of visual information, such as colors and shapes, during a short period of time. VSTM is a part of short-term memory, which can hold information up to 30 seconds. In this paper, we present the results of research where we classified the data gathered by using an electroencephalogram (EEG) during a VSTM experiment. The experiment was performed with 12 participants that were required to remember as many details as possible from the two images, displayed for 1 minute. The first assessment was done in an isolated environment, while the second assessment was done in front of the other participants, in order to increase the stress of the examinee. The classification of the EEG data was done by using four algorithms: Naive Bayes, support vector, KNN, and random forest. The results obtained show that AI-based classification could be successfully used in the proposed way, since we were able to correctly classify the order of the images presented 90.12% of the time and type of the displayed image 90.51% of the time.

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Dynamic Visual Noise Affects Visual Short-Term Memory for Surface Color, but not Spatial Location

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169/a000003 ◽

2010 ◽

Vol 57 (1) ◽

pp. 17-26 ◽

Cited By ~ 19

Author(s):

Kevin Dent

Keyword(s):

Short Term Memory ◽

Spatial Location ◽

Visual Noise ◽

Dynamic Visual Noise ◽

Short Term ◽

Surface Color ◽

Term Memory ◽

Visual Short Term Memory ◽

Experimental Tool ◽

Spatial Locations

In two experiments participants retained a single color or a set of four spatial locations in memory. During a 5 s retention interval participants viewed either flickering dynamic visual noise or a static matrix pattern. In Experiment 1 memory was assessed using a recognition procedure, in which participants indicated if a particular test stimulus matched the memorized stimulus or not. In Experiment 2 participants attempted to either reproduce the locations or they picked the color from a whole range of possibilities. Both experiments revealed effects of dynamic visual noise (DVN) on memory for colors but not for locations. The implications of the results for theories of working memory and the methodological prospects for DVN as an experimental tool are discussed.

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Time Window from Visual Images to Visual Short-Term Memory: Consolidation or Integration?

Experimental Psychology (formerly Zeitschrift für Experimentelle Psychologie) ◽

10.1027/1618-3169.51.1.45 ◽

2004 ◽

Vol 51 (1) ◽

pp. 45-51 ◽

Cited By ~ 21

Author(s):

Yuhong Jiang

Keyword(s):

Short Term Memory ◽

Time Window ◽

Short Interval ◽

Visual Images ◽

Short Term ◽

Temporal Window ◽

Term Memory ◽

Visual Short Term Memory ◽

Probe Task ◽

Long Time

Abstract. When two dot arrays are briefly presented, separated by a short interval of time, visual short-term memory of the first array is disrupted if the interval between arrays is shorter than 1300-1500 ms ( Brockmole, Wang, & Irwin, 2002 ). Here we investigated whether such a time window was triggered by the necessity to integrate arrays. Using a probe task we removed the need for integration but retained the requirement to represent the images. We found that a long time window was needed for performance to reach asymptote even when integration across images was not required. Furthermore, such window was lengthened if subjects had to remember the locations of the second array, but not if they only conducted a visual search among it. We suggest that a temporal window is required for consolidation of the first array, which is vulnerable to disruption by subsequent images that also need to be memorized.

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