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Cogs 143 * Lecture 7: LESSONS FROM THE STUDIES

Sociological Issues Language abilities in nonhumans is a threatening concept to many, even today! - “In the beginning was the Word” Language is what separates us from the beasts! - Makes us second only to the angels, reveals the soul, gives us dominion, from God not evolution - “The proper study of Man is Man” What matters is how we are different, special - Language defines us, entails our unique traits: Rational, abstract thought, Culture, Ethics etc. - “The Language Instinct” (Pinker 1994) A function of specialized, -specific brain modules - e.g. Chomsky’s 1957 “Language Acquisition Device”; 2001: “FoxP2 Gene” (re: speech) - All of the above and more shape the attitudes of researchers, critics, funders, the public - Science is situated; its topics, theories, and methods are all a product of the cultural milieu

Species-Appropriate Design (Note presumption in originally only attempting with ; Still no monkeys) - Earliest work (Kelloggs) with chimps attempted to teach them to speak, failed - Do not have human articulatory apparatus (mouth shape, tongue position, sensori-motor coord) - Altho note: tested, understands much spoken English (reference, novel combinations) - Chimps’ spontaneous use/development of gesture => Teach them - Some by imitation, mostly involved shaping ’s hands into signs - In 1960s, beginning to be recognized as a “true” language - Multiple species trained: Chimps (e.g. ) (e.g. ) (e.g. ) - Dolphins, handless, trained mainly for comprehension (vs. production) of signs/sign sequences - Some attempt (e.g. Phoenix) with imitation of acoustic computer-generated symbols, stalled - Note all involve testing if animals can master human-like linguistic structures

Methodological Critiques Includes scathing reviews**, fierce debates, undermined credibility - Poor data recording – e.g. Home-raised, naturalistic signing day in/out, no record of learning process - Little/no scientific “controls” – e.g. Inadvertent cuing by trainers, situation-specific associations, etc. - Poor data reporting – Early studies esp only report successful use of signs, not nonsense or incorrect - Biased reporting – e.g. Patterson/Koko over-rich interpretations (conversations about death, capture) - Method shift from sign language to tokens or keyboard (Premack, Rumbaugh, Savage-Rumbaugh, Matsuzawa) - In latter, every “utterance” by trainers and animals is recorded & analyzed

DATA: Linguistic Analyses -The study of human language traditionally divided into Semantics, Syntax, and Pragmatics…

Semantics Overall good evidence for the use and comprehension of symbols - Premack/: Blue triangle as symbol for apple, Ask “COLOR-OF?”, Sarah answers “Red” - i.e. Responds based on properties of evoked representation, not perceptual properties of symbol - (Recall difference between perc-based pigeon MTS and relation-based primate MTS) - Transfer symbol to novel context: e.g. If learn symbol as part of requesting sequence (GIVE BALL) - Dolphins, Apes can immediately respond to that symbol in IS BALL HERE? or WHATS THIS? - Except, some chimps fail; i.e. Post rote sequence learning, cannot transfer symbol to new task -e.g. Rumbaugh/: 1600 keyboard trials, correct sequences, but cannot apply object name -e.g. Terrace/Nim: Endless signing drills, some regularity of use, no transfer - Novel combinations by Apes, esp of signs: e.g. WATER BIRD=swan; WHITE TIGER=zebra etc.

Syntax Support for some simple aspects, not for more complex - Order Effects: Dolphins, Apes discrim ROGER TICKLE WASHOE vs WASHOE TICKLE ROGER - Similarly, can discriminate PUT A ON B vs. PUT B ON A (map order to spatial relations) etc. - Schema (Slot-in-Frame Grammar) Regularities in position of nouns, verbs, modifiers establish slots - Dolphins, Apes can learn new term from its place (the slot it fills) in a familiar sentence frame - e.g. GREY HOOP FETCH, new term “GREY” in presence of new & old colors, first trial correct - Plus, Dolphins can classify objects as named/unnamed, i.e. per role in schema structure - Embedding (Sub-Assembly) Rarely tested even though a significant aspect of human language - e.g. : “He said that she said that they thought that she wanted to go, but she didn’t.” - Dolphins trained LEFT HOOP FETCH (Get left hoop) & FRISBEE HOOP FETCH (Bring hoop to frisbee) immediately did FRISBEE LEFT HOOP FETCH (Bring left hoop to frisbee)

** Terrace, H et al. 1979, “Can an ape create a sentence?” Science 206: 891-902. Fouts, R 1976, Apes, Men and Language. Penguin Petito L.A. & Seidenberg (1979) “On the evidence for linguistic abilities in signing apes. Brain & Language 8:162-183 Pragmatics How language is used, how meaning arises from use - Social Interaction - Least successful projects (no symbol learning, no transfer) involved minimal social interaction - Terrace/Nim: Trained in controlled lab setting, large # of trainers, little socialization - Rumbaugh/Lana: 1000’s trials, interacting with machine (MACHINE GIVE LANA APPLE) -Most successful projects empahsize social, e.g. Savage-Rumbaugh & Rumbaugh: Sherman & Austin - First trained Sherman & Austin like Lana, again no transfer - Switched to interactive “Functional Tool Task” – i.e. Train in communicative context (duh!) - Exper [E] baits opaque site, demonstrates & helps Chimp [C] use tool to extract, share food - Once C proficient, E re-bait &, as C reaches for tool, E enter sequence “This Wrench” - C immediately entered “Give Wrench”, E enter “Yes, Give Austin Wrench” & gave - C given any tool requested, even if wrong - soon reject wrong & re-request other - Added new tools, new locations to use familiar tools, quickly learned new terms - TEST: First trials asked “Name This” about any tool > Immediate success - Interpretation: Conversational use of keyboard  Treat keys as functional symbols - Approximates natural context of language learning - Note: Sherman & Austin easily shifted to playing these roles when only one had access to tools and only the other to baited site (would request appropriate tool, give, share food) - Would play this “co-op game” w/keyboard later even while in same room! - Imperatives vs. Declaratives - are the latter Human Specific? -NHPs produce mainly imperatives (commands, requests etc.); Declaratives rare - e.g. “Give treat” “Tickle Washoe” “Go outside?” “Hurry!” (About concrete events) - In contrast, Humans produce many declaratives, uttered to draw attention to, comment on, events - e.g. “Look! See Spot run!” “That’s cool!” “Have you ever seen anything like it?!” - Some argue primary function of language to direct other’s attention (to topic, event, emotion etc) - At least some declaratives make reference to mental events (“Did you know he liked it?”)

- More on pragmatics to come…!

Cognitive “Upgrade” ? Premack, D 1983, “Codes of Beasts and Men” Behavioral & Brain Sciences 6:125-168 - How does language/symbol use change, improve/expand cognitive abilities (including in Humans)? -e.g. Boysen’s Sheeba, trained with numerals, helps on Greedy-Giveaway Task - Suggests symbol intervening between animal/treat enables delayed response, rational choice - e.g. Premack’s Sarah, only chimp reliably successful on Analogies - Facilitated by having extensive experience with symbols for SAME and DIFFERENT? - Human Enculturation effects still not well studied or understood; requires new methods, models ! - Raising chimpanzee as a child, produces a creature that is neither chimp nor human… - Can do many things that several researcher’s claim requires human evolved brain! - e.g. Gardners & Fouts’s Washoe, sign-language trained, including having her hands molded - She taught her offspring signs, molded his hands - e.g. Savage-Rumbaugh’s Kanzi, human raised, extensively lang-trained, taught to flint knap etc -e.g. Passes tests on , imitation, does teaching, etc. - More on Enculturation, including species-typical enculturation in primates and cetaceans to come…!

Researchers – Primary Subject - Species – Decade begun (*Still ongoing) – Focus of work Kellogg & Kellogg – , Chimp, 1930s, Speech, gesture, imitation, pretense Hayes & Hayes – , Chimp, 1950s, Speech, gesture, imitation, pretense Gardner & Gardner/Fouts – Washoe, Chimp, 1960s*, American Sign Language Rumbaugh – Lana, Chimp, 1970s, Keyboard Terrace – Nim, Chimp, 1970s, American Sign Language (Only subject NOT home-raised) Premack - Sarah, Chimp, 1970s, Complete sequence of tokens, Plus cognitive Tasks (e.g. Analogies, ToM) Savage-Rumbaugh & Rumbaugh - Sherman & Austin, Chimps, 1970s, Keyboard, Plus cognitive tasks Savage-Rumbaugh – Kanzi, , 1980s*, Keyboard, Also tested on speech comprehension, cognitive tasks Herman – Akeakami, Bottlenose Dolphin, 1980s, Comprehension of Signs, Plus cognitive tasks Herman – Phoenix, Bottlenose Dolphin, 1980s, Imitation of acoustic symbols, Plus cognitive tasks Matsuzawa – , Chimp, 1980s*, Keyboard, Plus cognitive tasks, including numerals Patterson - Koko, , 1980s*, American Sign Language Miles- Chantek, Orangutan, 1980s*, American Sign Language, Imitation Boysen – Sheeba & Sarah Chimps, 1980s, Premack’s Sarah, Sheeba trained in numerals, other cognitive tasks

NOTE: A few other species have also been so trained, showing many of the same above skills e.g. Pepperberg - , African Grey Parrot; Schusterman - Rocky, Sealion; Kaminski - , Dog;