Number form

Number form
This article refers to the neurological phenomenon. For Unicode numbers, see Number Forms.
A number form from one of Francis Galton's (1881b) subjects. Note the convolutions, and how the first 12 digits correspond to a clock face.

A number form is a mental map of numbers, which automatically and involuntarily appears whenever someone who experiences number-forms thinks of numbers. Numbers are mapped into distinct spatial locations and the mapping may be different across individuals. Number forms were first documented and named by Sir Francis Galton in his The Visions of Sane Persons (Galton 1881a). Later research has identified them as a type of synesthesia (Seron, Pesenti & Noël 1992; Sagiv et al. 2006).

Contents

Neural Mechanisms

It has been suggested that number-forms are a result of "cross-activation" between regions of the parietal lobe that are involved in numerical cognition and angular gyrus for spatial cognition (Ramachandran & Hubbard 2001; Hubbard et al. 2005). Since the areas that process numerical and spatial representations are close to each other, this may contribute to the increased cross-activation. Compared to non-synesthetes, synesthetes display larger P3b amplitudes for month cues, but similar N1 and P3b responses for arrow (<- or ->) and word (left or right) cues. (Template:Teuscher).

Reaction Times

Reaction time studies have shown that number-form synesthetes are faster to say which of two numbers is larger when the numbers are arranged in a manner consistent with their number-form, suggesting that number forms are automatically evoked (Sagiv et al. 2006; Piazza, Pinel & Dehaene in press). This can be thought of as a "spatial Stroop" task, in which space is not relevant to the task, but which can hinder performance despite its irrelevance. The fact that synesthetes cannot ignore the spatial arrangement of the numbers on the screen demonstrates that numbers are automatically evoking spatial cues. The reaction times for valid cues are smaller than invalid cues (words and arrows), but in synesthetes the response time differences for months are larger than those of non-synesthetes (Template:Teuscher).

Difference between number line

These number forms can be distinguished from the non-conscious mental number line that we all have by the fact that they are 1) conscious, 2) idiosyncratic (see image) and 3) stable across the lifespan. Although this form of synesthesia has not been as intensively studied as grapheme-color synesthesia, it seems reasonable to assume that similar neural mechanisms might be involved, but acting in different brain regions. Future studies will need to be conducted to test this hypothesis.

References

  • Piazza, M.; Pinel, P.; Dehaene, S. (in press), "Objective correlates of a peculiar subjective experience: a single-case study of number-form synaesthesia", Cognitive Neuropsychology 
  • Sagiv, N.; Simner, J.; Collins, J.; Butterworth, B.; Ward, J. (2006), "What is the relationship between synaesthesia and visuo-spatial number forms?", Cognition (101): 114–128 
  • Seron, X.; Pesenti, M.; Noël, M.-P. (1992), "Images of numbers, or When 98 is upper left and 6 sky blue", Cognition 44: 159–196 
  • Teucher, U.; Brang, D.; Ramachandran, V.; Coulson, D. (2010), "Spatial cueing in time-space synesthetes: An event-related brain potential study", Brain and Cognition (74): 35–46 

Wikimedia Foundation. 2010.

Игры ⚽ Нужно решить контрольную?

Look at other dictionaries:

  • number form —    The term number form was introduced in or shortly before 1880 by the British scientist Sir Francis Galton (1822 1911) to denote a mental map or configuration of numbers which may appear automatically and involuntarily whenever one thinks of… …   Dictionary of Hallucinations

  • number-form synaesthesia —    A term used to denote a type of * synaesthesia characterized by the automatic and involuntary appearance of a mental map or configuration of numbers whenever one thinks of numbers. These maps or configurations, referred to as * number forms,… …   Dictionary of Hallucinations

  • Number line — For other uses, see Number line (disambiguation). In basic mathematics, a number line is a picture of a straight line on which every point is assumed to correspond to a real number and every real number to a point.[1] Often the integers are shown …   Wikipedia

  • Number prefix — Number prefixes are prefixes derived from numbers or numerals. In English and other European languages, they are used to coin numerous series of words, such as unicycle – bicycle – tricycle, dyad – triad – decade, biped – quadruped, September –… …   Wikipedia

  • Number Six (Battlestar Galactica) — Number Six Battlestar Galactica character Promotional still of Number Six in season four First appearance …   Wikipedia

  • Form criticism — is a method of biblical criticism that classifies units of scripture by literary pattern (such as parables or legends) and that attempts to trace each type to its period of oral transmission. [ form criticism. Encyclopædia Britannica. 2007.… …   Wikipedia

  • Number Girl — Origin  Japan, Fukuoka Genres Alternative rock, post hardcore, indie rock …   Wikipedia

  • number — or [num′bər] n. [ME nombre < OE < L numerus: see NOMY] 1. a symbol or word, or a group of either of these, showing how many or which one in a series: 1, 2, 10, 101 (one, two, ten, one hundred and one) are called cardinal numbers; 1st, 2d,… …   English World dictionary

  • Form classification — is the classification of organisms based on their morphology, which does not necessarily reflect their biological relationships. Form classification, generally restricted to palaeontology, reflects uncertainty; the goal of science is to move form …   Wikipedia

  • Number Six (The Prisoner) — Number Six is the central fictional character in the 1960s television series The Prisoner, played by Patrick McGoohan. In the AMC remake, the character is played by Jim Caviezel, renamed Six . In several episodes, his attempts to escape his… …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”