Part VIII  COGNITION
A. Comparative use of SIGNALS & SYMBOLS
	1. Orders of Intentionality
		a. 0-Order and 1st-Order signs
		b.  2nd-Order and 3rd-Order symbols
	2.  Dolphin Vocal Communication
		a.  Flexible vocal signals
		b.  Failure on a 2nd-Order Task
	3. Chimpanzee Language Training
		a.  2nd-Order symbol mastery: "name-of"
		b. Cognitive components of symbol relations:
			1. Analogical reasoning
			2.  Syntax use & transitive reasoning

B. Brain Systems of Cognition & Language		
	1. Hemispheric Specialization
		a. Stimulation in conscious humans
		b.  Wada test
	2.  Feature analysis
		a.  Speech vs. melody
		b.  Sequential vs. spatial 
	3. Split-Brain Humans
		a.  Facial recognition
		b.  Object naming
		c.   Reading
	4. Cortical mechanisms of language
		a.  Broca's aphasia
		b.  Wernicke's aphasia

READING : : 	Premack in Coursepack (for part A)
		Kalat Chapter 14 (for part B)
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PART A: COMPARATIVE COGNITION

Communication means signaling events
-But the KIND OF MEANING a signal carries can be of many different kinds in terms of levels of complexity
	A human cry of pain is reflexive.  A shouted warning is voluntary and semantic (it carries the meaning you intend to express).  But both are signals, and both carry information to a listener.
The cognitive question concerning animal communication is: which human example do they most closely approximate?

Communicative signals can be rated as carrying 'degrees of meaning' 
using  "Orders of Intentionality" scale:
0 Order intentionality = Signal in direct response to event or emotion   

FIRST ORDER INTENTIONALITY = signal emitted as instrumental act to make others do something.
SECOND ORDER INTENTIONALITY = signal emitted to convey semantic proposition to make others believe something.  This requires that the signaler recognize that others are capable of such beliefs too, and that language codes the meaning to be believed.

To make a  signal versus symbol dichotomy, 
O and 1st order communications are merely signals.
2nd order and higher communications use real symbols.

Example 1:
DOLPHINS (Tursiops truncatus) use complex vocal calls in social situations.
Bastian  trained 2 dolphins to make a spatial choice in response to a colored light.  Then he arranged that only one dolphin could see the light.  Although performance dropped to chance, it gradually recovered to near perfect, as the dolphins developed a vocal cue system.  The question was whether this cue was emitted and recognized as a symbol for the light/choice or as a mere instrumental response/discriminative signal.  To answer this, the sender/receiver roles were reversed.  Performance dropped again to chance, and rose no more quickly than before.  Even if the original sender's own calls were played back, the sender failed to use them.  These failures indicated that the vocal cues were not used as symbols.
Example 2.
Chimpanzee (pan troglodytes) 'language training'
Washoe uses many ASL signs.  Suggestive evidence for second-order use comes from the application of words to new situations and from the apparent coinage of new words (e.g., 'water-bird').

But this is weak evidence.  Stronger proof comes from Premack's studies of Sarah and recent studies showing that chimpanzees can understand:
1. Analogous relationships between objects and their symbols.
2. Symbol-as-concept: Sarah's "name-of" word/concept.
3. That object relationships are represented by syntax relationships (in, on, under, etc)

Examples of representational reasoning:
- Analogy problem solving (Lock : Key   ::   Can : ?    (paint brush, can opener)
- Transitive inference (A>B   B>C   C>D   D>E ;  Is  D > B ?  ) 
- Proper use of syntax (placing new words [object, action, agent] in appropriate position in sentences) Rules of syntax
	---BUT Sarah and other chimpanzees never generate new syntax 

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Brain Lateralization:

Anatomical.
Although left and right brain are almost perfect mirror images, there are still several neuroanatomical asymmetries. Temporal Cortex  PLANUM TEMPORALE  (top of temporal lobe) is larger on left side in 75% of people.

Psychological.
- Lesions: Effects of brain DAMAGE differ depending on left or right brain
	-Left: problems of language are more common
	-Right: problems of spatial imagery and emotional expression ( & perception)

- Stimulation: Penfield stimulated cortex of conscious patients.  Right hemisphere stimulation led to evoked memories or images.  Left hemisphere stimulation led to aphasia (speech disruption).

- Hemispheric deactivation: Wada Test.  Sodium amytal anesthesia injected into carotid artery:
LEFT disrupts language in 96% of right-handers and 70% of left handers.  RIGHT disrupts 4% of right handers and 30% of left handers.  Thus language tends to be lateralized on the left (major factor), but this is modulated by motor dominance or handedness (minor factor).

-Lateralization In Normal Brains
DICHOTIC LISTENING:
-Melodies = Better recall from left ear (except for musicians)
- Language = Better recall from right ear

SOMATOSENSORY DETECTION
Right hand has advantage for sequential patterns
Left hand has advantage for spatial localization

Left brain sequential/vocalization dominance is shared by nonhuman animals:
-Ex: Japanese Macaques have a right ear advantage for recognizing species vocalizations -
 
Sex differences in normal lateralization
	1. Lesion effects:  Women are more likely to have bilateral language representation than men.
	2. Women tend to have higher cortical thickness, steroid receptor density, etc. on left side of brain.  Men have higher levels on right side of brain.
These are minor anatomical differences, with at most slight functional consequences.

SPLIT BRAIN PATIENTS
Corpus Callosum transection separates hemispheres of the brain.

-In facial identification tasks, patients choose face corresponding to what they saw in their left visual field) Saw
- In verbal naming tasks, patients can only name objects seen in right visual field.
- Written words can be read aloud only when in the right visual field (although other field can convey simple commands).

Language specializations in the left brain: revealed by aphasia after localized lesions.
-Broca's Aphasia after frontal lobe damage (production aphasia)
	a. Difficulty speaking, poor articulation
	b. "Telegraphic Speech" lacking grammatical connectives (and, or).
	c. Syntax perception deficits. 
-
2. Wernicke's Aphasia after temporal lobe damage (semantic aphasia)
	a.  Fluent but meaningless speech
	b.  Poor comprehension of conversation 
	c. Unable to name simple objects