Modularity DAY 13 – Sept 25, 2013

MODULARITYDAY 13 – SEPT 25, 2013

Brain & LanguageLING 4110-4890-5110-7960NSCI 4110-4891-6110Harry HowardTulane University

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Course organization• The syllabus, these slides and my recordings are

available at http://www.tulane.edu/~howard/LING4110/.• If you want to learn more about EEG and neurolinguistics,

you are welcome to participate in my lab. This is also a good way to get started on an honor's thesis.

• The grades are posted to Blackboard.

9/25/13 Brain & Language - Harry Howard - Tulane University

http://www.tulane.edu/~howard/LING4110/

REVIEWEEG, ERP & MEG

9/25/13 Brain & Language - Harry Howard - Tulane University 3

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The basic fact about dipoles

A dipole has a direction … … which in cortex is perpendicular to its surface


Brain & Language - Harry Howard - Tulane University 59/25/13

Language areas of the brain

Brain & Language - Harry Howard - Tulane University 69/25/13

The Broca-Wernicke-Lichtheim model (of the LH)

MODULARITYIngram §4


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But first …


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Fodor’s criteria for modularityProperty Vision Language

Specific to a domain color & edge detectors phonetic feature detectors

Operates mandatorily you can’t stop seeing (with your eyes open)

you can’t stop hearing English as English

Limits central access how do you see? how do you hear English as English?

Acts quickly image recognition < 200ms? word recognition < 200 ms?

Information is encapsulated

other senses don’t affect vision (but synesthesia)

other senses don’t affect speech recognition

Analyzes ‘shallowly’ early vision extracts edges early language only assigns superficial structure

Fixed neural structure eg V1 perisylvian region

Fails in a specific way visual agnosia BWL model

Matures in a specific way (?) stages in child acquisition


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The problem• Fodor’s nine properties of modularity are organized

haphazardly.• They should be grouped into those that are necessary to any sort

of modular process, and those that are just by-products of modularity, perhaps in a specific process.

• We do this in the next slide.


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Coltheart’s grouping & my explanation

1. Specific to a domain2. Information is

encapsulated3. Fixed neural

structure4. Matures in a specific

way5. Fails in a specific

way6. Limits central access7. Operates mandatorily8. Acts quickly9. Analyzes ‘shallowly’

1. by definition.2. by definition.3. in order to keep out all the other stuff.4. in order to build the fixed structure.5. because it was built in a specific way.6. in order to keep out other stuff.7. since there is no external access, it can’t

be turned on or off.8. because there is no other stuff to get in

the way of optimizing speed.9. because other stuff is necessary to

analyze deeply.


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A new problem: What is meant by ‘built’?

• If it means, ‘constructed by neurogenesis in the developing brain’ …• … then the only modular abilities are sensory and motor, plus language.• [NOTE: sensory and motor pathways are peripheral in the nervous

system.]• This is what Fodor means, and what Chomsky means, too.• Language has to be a mutation, added to the others.

• However, if it means ‘learned’ …• … then we may have dozens of modular abilities.• This is what Coltheart means.• Coltheart was inspired by connectionism, a mathematical technique for

teaching computers how to learn, which gained popularity in the mid-80s, before Fodor’s work.

• Language could be entirely learned.


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So how can Coltheart know?

dementia aphasiacognition ✖ ✔language ✔ ✖


By a double disassociation.My example:

If you don’t understand this, read about Coltheart’s example of the chocolate factory.

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Summary• Fodor asks, given some notion of modularity, is there any

cognitive ability that satisfies it?• Yes, following the nine criteria, just peripheral sensory and motor

processing, plus language.• Coltheart asks, given some cognitive ability, is it modular?

• Yes, following just the top two criteria, just about any cognitive ability could be modular.

• Connectionism supplies a theory of learning that shows how this could happen.

• The truth is somewhere between the two.• Language is learned, but humans have a genetic predisposition

(given by specific neural pathways) to learn it quickly and accurately.


NEXT TIMEIngram §5.

☞ Go over questions at end of chapter.


Modularity DAY 13 – Sept 25, 2013

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