• Words are arbitrary. There is rarely any inherent link between the sound of a word and what it represents
(or between the written form and what it represents).



English	Tree
German	Baum
French	Arbre
Spanish	Arbol
Russian	Derevo

• We use and develop words that are important for our lives.

For example, Arabic has scores of words for "camel."
Think about it conversely: Who needs to talk about bamboo at the North Pole?

• Because the system of language is by nature abstract, it allows us to think abstractly (see video).

i. we can speak of things past that we never saw
ii. we can speak of things that haven't yet happened, and which may never happen
iii. we can speak of things as they might be, should be, and could be; all potentialities may be linked to conditions

1. Do you remember when your parents taught you relative clauses or how to make a past tense?
   
   
2. How did you learn?
   
   
   1. Repeat what you heard? Where do kids hear:

      Daddy go.

      Daddy no go.

      Bobby cookie (for my cookie)

   2. Positive and negative reinforcement?
      1. Children are corrected for what they say not how they say it
         (e.g., child rewarded for "daddy no go" if daddy is, in fact, not going)
         
         
      2. Children are rewarded (with laughter) for errors, e.g.:

      tree-knocker

      underbrella

      beach-lookers

   3. Errors are almost always correct forms in other languages

      No daddy go

      Daddy no going

      Daddy isn't going

   4. Children build grammatical theories, internal grammars, until theirs matches that of everyone else's.

1. Grammar Loss without Cognitive Loss
   1. Broca's and Wernicke's aphasia
      1. Broca's aphasia (agrammatism):loss of grammatical morphemes
      2. Wernicke's aphasia (fluent aphasia): loss of lexemes
   2. SLI (Specific Language Impairment)
      1. ostensibly genetically determined (runs in families)
      2. late onset of acquisition
      3. speak slowly & deliberately--speaking becomes strenuous mental work
      4. persistent grammatical errors into adulthood

      1. errors in grammatical functions: pronouns, agreement

         It's a flying finches, they are.

         The boys eat four cookie

         Carol is cry in the lunch

      2. fail the 'wug' test (if there is more than 1 how do you say it):

         'Wug. . . wugness, isn't it. No, I see. You want a pair . . . pair it up. OK.'

      3. cognitively normal, even bright. Can score high in math, a subject not dependent on language

2. Cognitive Loss without Grammar Loss
   1. Hydrocephalus from spinal bifida (Denyse of psychologist Richard Cromer)
      1. severely retarded -- cannot read or write
      2. speaks normally with no grammatical errors
   2. Williams syndrome (defective gene in chromosome 11)
      1. significantly retarded (IQ 50), can't tie their shoes
      2. loquacious, especially like unusual words: prefer ibex, yak, unicorn to dog, cat