Connectedness Affects Dot Numerosity Judgment: Implications for Configural Processing

By He, Lixia; Zhang, Jun et al. | Psychonomic Bulletin & Review, June 2009 | Go to article overview

Connectedness Affects Dot Numerosity Judgment: Implications for Configural Processing


He, Lixia, Zhang, Jun, Zhou, Tiangang, Chen, Lin, Psychonomic Bulletin & Review


Participants judged the number of dots in visual displays with brief presentations (200 msec), such that the numerosity judgment was based on an instantaneous impression without counting. In some displays, pairs of adjacent dots were connected by line segments, whereas, in others, line segments were freely hanging without touching the dots. In Experiments 1, 2A, and 2B, connecting pairs of dots by line segments led to underestimation of dot numbers in those patterns. In Experiment 3, we controlled for the number of freely hanging line segments, whereas Experiment 4 showed that line segments that were merely attached to dots without actually connecting them did not produce a considerable underestimation effect. Experiment 5 showed that a connectedness effect existed when stimulus duration was reduced (50 msec) or extended (1,000 msec). We conclude that connectivity affects dot numerosity judgments, consistent with earlier findings of a configural effect in numerosity processing. Implications of the role of connectedness in object representation are discussed.

The term numerosity judgment refers to the estimation of the number of dots in a pattern made of a multitude of dots, or to comparing the dot numbers of two such patterns, under a short presentation duration to preclude overt or covert counting, with the judgment based solely on an instantaneous impression of numerosity. In a typical numerosity comparison task, a participant is briefly presented with two visual displays of dots and is asked to indicate which contains more dots. In a typical numerosity estimation task, a participant is asked to provide an estimate of the dot number in a display without actually performing one-by-one counting. Earlier researchers (Indow & Ida, 1977; Krueger, 1972, 1984) constructed psychophysical scales and described numerosity as a power function of the number of items in the stimulus (with an exponent of around 0.85). A participant's ability to discriminate numerosity was found to be invariant against (i.e., irrespective of) dot size (Allik, Tuulmets, & Vos, 1991), although his or her ability to estimate numerosity bore an inverse relationship to dot size (Ginsburg & Nicholls, 1988). Errors in discrimination of numerosity were shown to be related not only to the randomness (external variance) of dots-per-unit area in the dot patterns themselves but also to the internal noise (observer variance) generated by the observer (Burgess & Barlow, 1983).

A well-documented finding in numerosity research is that spatial configuration of elements (dots) exerts a profound influence on perceived numerosity: Compared with dots in random distribution, dots in regular arrangements (such as in concentric circles) tend to be overestimated, whereas dots forming clusters are underestimated (Allik & Tuulmets, 1991; Ginsburg, 1978; Ginsburg & Goldstein, 1987). The same pattern of results was replicated in children 5.8-14.6 years of age (Ginsburg & Deluco, 1979). These findings were explained by the so-called "occupancy model" (Allik & Tuulmets, 1991), which claimed that perceived numerosity depended on the subjective area covered by the totality of dots in a dot pattern; the impact of each dot was postulated to have some local spatial spread into its immediate neighborhood. Each dot supposedly occupied a circular territory of a fixed radius larger than its physical size, so when two dots were close to one another, there was an overlap in their individual territory such that the total effective region covered by the dots was smaller than it would have been if the two dots had been more widely separated. Decreasing the distance of adjacent dots-according to the occupancy model- caused more overlapping apparent area, leading to underestimation of dot numerosity.

In addition to the effect of the spatial arrangement of dots on perceived numerosity, there are nonspatial, structural factors affecting numerosity perception. …

The rest of this article is only available to active members of Questia

Sign up now for a free, 1-day trial and receive full access to:

  • Questia's entire collection
  • Automatic bibliography creation
  • More helpful research tools like notes, citations, and highlights
  • Ad-free environment

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
One moment ...
Default project is now your active project.
Project items

Items saved from this article

This article has been saved
Highlights (0)
Some of your highlights are legacy items.

Highlights saved before July 30, 2012 will not be displayed on their respective source pages.

You can easily re-create the highlights by opening the book page or article, selecting the text, and clicking “Highlight.”

Citations (0)
Some of your citations are legacy items.

Any citation created before July 30, 2012 will labeled as a “Cited page.” New citations will be saved as cited passages, pages or articles.

We also added the ability to view new citations from your projects or the book or article where you created them.

Notes (0)
Bookmarks (0)

You have no saved items from this article

Project items include:
  • Saved book/article
  • Highlights
  • Quotes/citations
  • Notes
  • Bookmarks
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

(Einhorn, 1992, p. 25)

(Einhorn 25)

1

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited article

Connectedness Affects Dot Numerosity Judgment: Implications for Configural Processing
Settings

Settings

Typeface
Text size Smaller Larger Reset View mode
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

Full screen

matching results for page

Cited passage

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn, 1992, p. 25).

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences." (Einhorn 25)

"Portraying himself as an honest, ordinary person helped Lincoln identify with his audiences."1

1. Lois J. Einhorn, Abraham Lincoln, the Orator: Penetrating the Lincoln Legend (Westport, CT: Greenwood Press, 1992), 25, http://www.questia.com/read/27419298.

Cited passage

Welcome to the new Questia Reader

The Questia Reader has been updated to provide you with an even better online reading experience.  It is now 100% Responsive, which means you can read our books and articles on any sized device you wish.  All of your favorite tools like notes, highlights, and citations are still here, but the way you select text has been updated to be easier to use, especially on touchscreen devices.  Here's how:

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select.

OK, got it!

Thanks for trying Questia!

Please continue trying out our research tools, but please note, full functionality is available only to our active members.

Your work will be lost once you leave this Web page.

For full access in an ad-free environment, sign up now for a FREE, 1-day trial.

Already a member? Log in now.