1 a discussion and extension of davidoff (2001). language and perceptual categorisation kelly...

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A discussion and extension of Davidoff (2001). Language and Perceptual CategorisationKelly Sorensen

Christopher Thomas

November 2, 2004

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Outline

1. Jules Davidoff

2. The Sapir-Whorf Hypothesis

3. Discussion of “Language and Perceptual Categorisation”

4. Discussion of Linguistic Relativism

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Prof. Jules Davidoff

Professor of Psychology, Goldsmiths College, University of London

Research:

mental representation of objects

relationship between the stored (memory) knowledge concerning objects and their recognition, categorisation and nameability

effects on the way speakers of a language perceive, categorize and remember colors

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Outline

1. Jules Davidoff




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Sapir-Whorf examples

Eskimos have four different words for snow, where English has just one aput for snow on the ground qana for falling snow piqsirpoq for drifting snow qimuqsuq for a snowdrift

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Whorf’s conclusion

"We have the same word for falling snow, snow on the ground, snow packed hard like ice, slushy snow, wind-driven flying snow -- whatever the situation may be. To an Eskimo, this all-inclusive word would be almost unthinkable; he would say that falling snow, slushy snow, and so on, are sensuously and operationally different, different things to contend with; he uses different words for them and for other kinds of snow."

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Whorf’s conclusion

difference in vocabulary

difference in attitude or perception

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Introduction to the Sapir-Whorf Hypothesis

In linguistics, the Sapir-Whorf Hypothesis states that there are certain thoughts of an individual in one language that cannot be understood by those who live in another language.

The hypothesis states that the way people think is strongly affected by their native languages.

It is a controversial theory championed by linguist Edward Sapir and his student Benjamin Whorf.

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Historical Notes

Whorf was fighting against cultural evolutionary theory saying that Western thought is the highest form of thought

“… Sapir and Whorf […] rejected hierarchical, quasi-evolutionary rankings of languages and cultures .in particular the European, especially Humboldtian, obsession with the superior value of inflectional languages for the cultural or mental advancement of a people.” (Lucy 1997)

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Historical Notes

After vigorous attack from followers of Noam Chomsky in the following decades, the hypothesis is now believed by most linguists only in the weak sense that language can have some small effect on thought.

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Sapir-Whorf hypothesis I

Linguistic relativity:• Structural differences between languages are

paralleled by nonlinguistic cognitive differences (the structure of the language itself effects cognition)

• The number and the type of the basic colour words of a language determine how a subject sees the rain bow

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Sapir-Whorf hypothesis II

Linguistic determinism = extreme "Weltanschauung“ version of the hypothesis:• The structure of a language can strongly

influence or determine someone’s World View• A World View describes a (hopefully)

consistent and integral sense of existence and provides a theoretical framework for generating, sustaining and applying knowledge

• The Inuit can think more intelligently about snow because their language contains more sophisticated and subtle words distinguishing various forms of it, etc.

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Sapir-Whorf hypothesis III

Arbitrariness• The semantic systems of different languages

vary without constraint.• This hypothesis must be tacitly assumed,

because otherwise the claim that Linguistic Relativity makes is rather undramatic.

• For each decomposition of the spectrum of the rain bow a natural system of colour words is possible

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Outline

1. Jules Davidoff




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Why/how do we determine category membership?

Davidoff (2001) argues: that it is linguistic similarity rather than perpetual

similarity that is critical for perceptual categorization

against the view that there are underlying, universal, neurophysiological mechanisms which determine how color is categorized

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The case for universal color categories:

Is based on knowledge of how wavelength-sensitive neurons function.

• Based on the opponent-process mechanism of neurons, it has been argued that there are two elemental achromatic categories

1. Black

2. White

• and four elemental color categories

1. Red

2. Green

3. Yellow

4. Blue

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The case for universal color categories cont.:

• There are two wavelengths for which opponent-process neurons R-G give no output.

• There is also a wavelength for which the opponent-process neurons Y-B give no output.

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Problems with the case for universal color categories:

Wavelengths chosen to represent the colors blue, yellow, and green are not consistent with what is expected based on neurophysiology

Conclusions about neurons are weakened by individual’s previous exposure to the concept of blue, yellow, or green

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Problems with the case for universal color categories:

Neurophysiology data show that neurons can respond selectively to particular wavelengths or combinations of wavelengths and brightness; no evidence, however, that neurons respond categorically.

Davidoff thus concludes that perceptual categories cannot be based strictly upon observation.

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The philosophical argument

The ‘Sorites paradox”

• Take a series of colors of decreasing wavelength with the change below the threshold for the human visual system

• Agree that a patch at one end can be called ‘red”

• If red is the observational or perceptual category, then the next patch must also be called red, and so on.

• Continuing with the logic we come to the illogical conclusion that all colors in the series are red, even the ‘blues” at the other end of the series

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The neuropsycological evidence

Patients with language impairments caused by brain damage often behave as if the Sorites paradox is a reality, sorting by perceptual similarity without regard for categorical boundaries.

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Cross-cultural theories

Whorfian view-”We dissect nature along the lines laid down by our language.”

Rosch- argued for a universal rather than language based color categories due to cognitive similarities between languages with few color terms and English.

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Rosch’s universal theory

Based upon studies of the Dani who

• have only two basic color terms but remembered colors in ways very similar to the English speakers

• Showed superior learning and memory for focal colors for which they had no linguistic terms

Results were widely accepted as proof of universal color categories

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Problems with Rosch’s universal theory

Davidoff argues that there are potentially serious flaws in both the design and interpretation of Rosch’s studies

Conflicting results found for the first study on two measures based on the multi-dimensional scaling of the same data

• Graphical demonstration showed support for universalist view

• Statistical results did not

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Problems with Rosch’s universal theory cont.

No explanation is given for conflicting results

Dani speakers perform poorly on the statistical measures for subsequent studies as well

Researchers unable to replicate findings with Berinmo population from New Guinea

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Categorical perception

Stimuli from the center of perceptual categories are classified faster than those at the edges, consequently discrimination of stimuli is better across than within categories

In studies with Berinmo and English speakers, classification was consistently more closely aligned with the linguistic categories than with the underlying perceptual universals

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Empirical support for Whorfian view (theory of linguistic similarity)

1st experiment

• When making judgements of similarity between a group of three stimuli, participants judged two stimuli from the same linguistic category to be more similar, even thought the perceptual distance between each pair of stimuli were held equal

• No reliable tendencies were observed for those belonging to groups which make no linguistic distinctions between the categories used

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Empirical support for Whorfian view (theory of linguistic similarity) cont.

2nd experiment

English speakers

1. found the division between green and blue easier to learn than the arbitrary division of green

2. found the division between yellow and green easier to learn than the division between the Berinmo color categories of nol and wor

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Berinmo speakers

1.Demonstrated no difference in difficulty for learning the green-blue division and the arbitraty green division

2.Found the nol-wor division significantly easier to learn than the yellow-green division

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3rd experiment

• Demonstrated an effect of linguistic category in recognition memory

1. English speakers showed significantly superior recognition for targets from cross-category pairs than for those from within-category pairs for the green blue boundary, but not for the nol-wor boundary

2. Berinmo speakers showed the opposite effect

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English and Berinmo Color Categories

English color categoriesBerinmo color categoriescomparison

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Davidoff’s conclusions from these 3 experiments

Categorical perception shows the influence of language on perception

The structure of linguistic categories distorts perception by stretching perceptual distances at category boundaries

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Interference studies

Has examined whether categorical perception can be disrupted with verbal interference

Verbal interference removed the cross-category advantage for speakers whose languages classifies the colors as belonging to different categories

It appears that verbal coding (representation of information verbal) facilitates recall (information is likely encoded both visually as well as verbally)

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Constraints on Whorfian view

The argument for color categories being a product of language does not mean that categorization is unrelated to properties of the visual system

• Similar items (as defined by perceptual discrimination) are universally grouped together (e.g. would not have yellow and blue together without also having green between)

• Even perceptual categorization tasks can sometimes be solved simply by perceptual similarity or common association

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Overall conclusions of the author

Perceptual categorization is determined by linguistic relativity

Being able to attend to color is different from understanding color categories

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Overall conclusions of the author

Cross-lingual evidence supports the Whorfian hypothesis in the number domain, in space, in time, and in speech perception

Language and cognition interact; children generalize abstract terms only if they have learned a label for the concrete-learning situation

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Questions for future research

Can human-primates form perceptual categories?

There is evidence that neonates show color categorization. Does this reflect categorization of a different type?

Are there capacity constraints on perceptual categorization?

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Questions for future research

Verbal interference affects categorization in memory tasks. Is the same true for perceptual tasks?

Which brain areas are involved in perceptual-categorization?

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Outline

1. Jules Davidoff




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More Evidence in favor of linguistic relativism

Chinese children count earlier than American children• (In part) because Chinese numbers are more systematic

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More Evidence in favor of linguistic relativism

Mayans’ similarity judgments are more influenced by material (as appropriate for mass nouns), rather than shape (as appropriate for count nouns)

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But then …

What does this evidence really say about the influence of language on thought?

Especially in the case of colors, is it more a matter of what we’ve learned? Painters can name more colors. We can look at colors from different points of

view• Warm or cold colors• Pastel or vivid colors

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Pinker against Sapir-Whorf

Supposed limitations on expression in various languages are based on faulty linguistic understanding. • Hopi does have words for time, etc. • Translation between languages is possible

(even if difficult to do elegantly).

http://www.ling.upenn.edu/courses/Spring_2002/ling001/thought.html

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Thought is possible without language. • Adults who have grown up without language. • Babies before they learn language. • Primates and other animals that never learn

language. • Adults who reason and create in visual or other

modes.


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Language is an inadequate medium for the direct encoding of thought. • We often can't think of the right word to

express ourselves. • Language contains ambiguity, homophony,

etc. • Manipulation of visual images is done directly. Pinker suggests a nonverbal language

which he calls Mentalese


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Questions

Do euphemisms make us think differently about a fact?• negative growth, collateral damage, peace

force• retarded, mentally disabled, mentally

challenged Does the convention of using the male form

support patriarchic views or is it just an indication?

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Questions

Can we think about categorization without language?• For visually similar items• For abstract categorizations

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The common denominator

In an experiment similar to Davidoff’s, Kay and Kempton came to the following conclusions:• The extreme ("Weltanschauung") version of

this idea, that all thought is constrained by language, has been disproved

• The opposite extreme – that language does not influence thought at all – is also widely considered to be false

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Synthesis?

Looking at Pinker’s objections, is there something underlying language that is more influential?

Is it the language that influences our perception or rather the culture we live in?

Lakoff suggests that cultures have deeply rooted conceptual metaphors thatfind their expressions in the languageguide our perception

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References

Paul Kay, Willett Kempton: What is the Sapir-Whorf Hypothesis? American Anthropologist, New Series, Vol. 86, No.1, March 1984, 65-79

http://www.ling.upenn.edu/courses/Spring_2002/ling001/thought.html Jules Davidoff: Language and Perceptual Categorisation.

TRENDS in Cognitive Sciences Vol.5 No.9 September 2001, 382-387

George Lakoff & Mark Johnson. (1980) Metaphors We Live By. Chicago: University of Chicago Press.

John A. Lucy. Linguistic Relativity. Annu. Rev. Anthropol. 1997. 26:291-312

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