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Marvin M. Chun

Bio: Marvin M. Chun is an academic researcher from Yale University. The author has contributed to research in topics: Visual search & Working memory. The author has an hindex of 72, co-authored 177 publications receiving 28308 citations. Previous affiliations of Marvin M. Chun include Stanford University & Vision-Sciences, Inc..


Papers
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Journal ArticleDOI
TL;DR: The data allow us to reject alternative accounts of the function of the fusiform face area (area “FF”) that appeal to visual attention, subordinate-level classification, or general processing of any animate or human forms, demonstrating that this region is selectively involved in the perception of faces.
Abstract: Using functional magnetic resonance imaging (fMRI), we found an area in the fusiform gyrus in 12 of the 15 subjects tested that was significantly more active when the subjects viewed faces than when they viewed assorted common objects. This face activation was used to define a specific region of interest individually for each subject, within which several new tests of face specificity were run. In each of five subjects tested, the predefined candidate “face area” also responded significantly more strongly to passive viewing of (1) intact than scrambled two-tone faces, (2) full front-view face photos than front-view photos of houses, and (in a different set of five subjects) (3) three-quarter-view face photos (with hair concealed) than photos of human hands; it also responded more strongly during (4) a consecutive matching task performed on three-quarter-view faces versus hands. Our technique of running multiple tests applied to the same region defined functionally within individual subjects provides a solution to two common problems in functional imaging: (1) the requirement to correct for multiple statistical comparisons and (2) the inevitable ambiguity in the interpretation of any study in which only two or three conditions are compared. Our data allow us to reject alternative accounts of the function of the fusiform face area (area “FF”) that appeal to visual attention, subordinate-level classification, or general processing of any animate or human forms, demonstrating that this region is selectively involved in the perception of faces.

7,059 citations

Journal ArticleDOI
TL;DR: In this article, the authors show that every individual has a unique pattern of functional connections between brain regions, which act as a fingerprint that can accurately identify the individual from a large group.
Abstract: This study shows that every individual has a unique pattern of functional connections between brain regions. This functional connectivity profile acts as a ‘fingerprint’ that can accurately identify the individual from a large group. Furthermore, an individual's connectivity profile can predict his or her level of fluid intelligence.

2,121 citations

Journal ArticleDOI
TL;DR: The results show how implicit learning and memory of visual context can guide spatial attention towards task-relevant aspects of a scene.

1,776 citations

Journal ArticleDOI
TL;DR: Results of Experiments 3-5 confirmed that AB is triggered by local interference from immediate posttarget stimulation and showed thatAB is modulated by the discriminability between the 1st target and the immediately following distractor.
Abstract: When 2 targets are presented among distractors in rapid serial visual presentation, correct identification of the 1st target results in a deficit for a 2nd target appearing within 200-500 ms. This attentional blink (AB; J. E. Raymond, K. L. Shapiro, & K. M. Arnell, 1992) was examined for categorically defined targets (letters among nonletters) in 7 experiments. AB was obtained for the 2nd letter target among digit distractors (Experiment 1) and also for a 3rd target (Experiment 2). Results of Experiments 3-5 confirmed that AB is triggered by local interference from immediate posttarget stimulation (Raymond et al., 1992) and showed that AB is modulated by the discriminability between the 1st target and the immediately following distractor. Experiments 5-7 further examined the effects of both local interference and global discriminability. A 2-stage model is proposed to account for the AB results. Researchers working on visual attention have focused on. capacity limitations that arise when multiple stimuli must be processed in a single spatial array. Different issues arise when stimuli are presented sequentially. In this study, we examined attentional limitations for processing a temporal sequence of visual stimuli. When participants search for targets among stimuli presented in a sequence at high rates, correct identification of one target produces a marked deficit for detecting a subsequent target appearing in a 200500 ms interval after the onset of the first one (Broadbent & Broadbent, 1987; Raymond, Shapiro, & Arnell, 1992). These tasks involve the use of rapid serial visual presentation (RSVP), in which each item replaces the previous one at the same spatial location. The RSVP paradigm has been a useful tool for researchers exploring the temporal characteristics of information processing because it provides the experimenter with precise control not only over the time a given item is in view, but also over the preceding and subsequent processing demands on the participants. In RSVP each item not only eliminates the previous item from sensory storage (Kahneman, 1968), but also presents a new item to be processed, thus constraining the time available for higher level cognitive as well as perceptual processing (Potter, 1976).

1,400 citations

Journal ArticleDOI
TL;DR: A taxonomy based on the types of information that attention operates over--the targets of attention is proposed, providing an organizing framework that recasts classic debates, raises new issues, and frames understanding of neural mechanisms.
Abstract: Attention is a core property of all perceptual and cognitive operations. Given limited capacity to process competing options, attentional mechanisms select, modulate, and sustain focus on information most relevant for behavior. A significant problem, however, is that attention is so ubiquitous that it is unwieldy to study. We propose a taxonomy based on the types of information that attention operates over—the targets of attention. At the broadest level, the taxonomy distinguishes between external attention and internal attention. External attention refers to the selection and modulation of sensory information. External attention selects locations in space, points in time, or modality-specific input. Such perceptual attention can also select features defined across any of these dimensions, or object representations that integrate over space, time, and modality. Internal attention refers to the selection, modulation, and maintenance of internally generated information, such as task rules, responses, long-term memory, or working memory. Working memory, in particular, lies closest to the intersection between external and internal attention. The taxonomy provides an organizing framework that recasts classic debates, raises new issues, and frames understanding of neural mechanisms.

1,039 citations


Cited by
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28 Jul 2005
TL;DR: PfPMP1)与感染红细胞、树突状组胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作�ly.
Abstract: 抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1(PfPMP1)与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用,在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员,通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

18,940 citations

Journal ArticleDOI
TL;DR: The data allow us to reject alternative accounts of the function of the fusiform face area (area “FF”) that appeal to visual attention, subordinate-level classification, or general processing of any animate or human forms, demonstrating that this region is selectively involved in the perception of faces.
Abstract: Using functional magnetic resonance imaging (fMRI), we found an area in the fusiform gyrus in 12 of the 15 subjects tested that was significantly more active when the subjects viewed faces than when they viewed assorted common objects. This face activation was used to define a specific region of interest individually for each subject, within which several new tests of face specificity were run. In each of five subjects tested, the predefined candidate “face area” also responded significantly more strongly to passive viewing of (1) intact than scrambled two-tone faces, (2) full front-view face photos than front-view photos of houses, and (in a different set of five subjects) (3) three-quarter-view face photos (with hair concealed) than photos of human hands; it also responded more strongly during (4) a consecutive matching task performed on three-quarter-view faces versus hands. Our technique of running multiple tests applied to the same region defined functionally within individual subjects provides a solution to two common problems in functional imaging: (1) the requirement to correct for multiple statistical comparisons and (2) the inevitable ambiguity in the interpretation of any study in which only two or three conditions are compared. Our data allow us to reject alternative accounts of the function of the fusiform face area (area “FF”) that appeal to visual attention, subordinate-level classification, or general processing of any animate or human forms, demonstrating that this region is selectively involved in the perception of faces.

7,059 citations

Journal ArticleDOI
TL;DR: A wide variety of data on capacity limits suggesting that the smaller capacity limit in short-term memory tasks is real is brought together and a capacity limit for the focus of attention is proposed.
Abstract: Miller (1956) summarized evidence that people can remember about seven chunks in short-term memory (STM) tasks. How- ever, that number was meant more as a rough estimate and a rhetorical device than as a real capacity limit. Others have since suggested that there is a more precise capacity limit, but that it is only three to five chunks. The present target article brings together a wide vari- ety of data on capacity limits suggesting that the smaller capacity limit is real. Capacity limits will be useful in analyses of information processing only if the boundary conditions for observing them can be carefully described. Four basic conditions in which chunks can be identified and capacity limits can accordingly be observed are: (1) when information overload limits chunks to individual stimulus items, (2) when other steps are taken specifically to block the recoding of stimulus items into larger chunks, (3) in performance discontinuities caused by the capacity limit, and (4) in various indirect effects of the capacity limit. Under these conditions, rehearsal and long-term memory cannot be used to combine stimulus items into chunks of an unknown size; nor can storage mechanisms that are not capacity- limited, such as sensory memory, allow the capacity-limited storage mechanism to be refilled during recall. A single, central capacity limit averaging about four chunks is implicated along with other, noncapacity-limited sources. The pure STM capacity limit expressed in chunks is distinguished from compound STM limits obtained when the number of separately held chunks is unclear. Reasons why pure capacity estimates fall within a narrow range are discussed and a capacity limit for the focus of attention is proposed.

5,677 citations

Journal ArticleDOI
TL;DR: A model for the organization of this system that emphasizes a distinction between the representation of invariant and changeable aspects of faces is proposed and is hierarchical insofar as it is divided into a core system and an extended system.

4,430 citations