1. Can Animals think? A behaviorist perspective on comparative cognition

2. Comparative Cognition Evolutionary approach: cognitive mechanisms evolve in response to selective pressures peculiar to each species’ ecology, physiology and morphology Thus cognitive processes differ across species Comparative cognition: compare abilities across species Analyze performance of different species on same set of tasks Focus on species-specific mechanisms and strategies that underlie problem- solving performance Better to understand how different animals problem solve rather than Try to determine which animal is “smarter” Must use a set of tasks, not a single task

3. What behaviors to study? Relearning Altering habits and adapting to change by switching to different solution routine Behavioral flexibility Neophilia Exploration strategies Attention Motivation Affordance learning Physiological constraints

4. Cognitive Ethology! Cognitive ethology assumes that animals are capable of conscious thought and intentionality Normally traits given just to humans Assumption is data driven: Animal behavior shows complexity, flexibility and cleverness Conscious intent is demonstrated by these behaviors

5. Experimental Psychology Experimental psychologists use comparative cognition in more limited way “objective evidence cannot give a demonstration either of the existence or the nonexistence of consciousness, thus consciousness is precisely that which cannot be perceived objectively.” Comparative cognition = theoretical constructs and models used to explain aspects of behavior that cannot be readily characterized in terms of simple S-R mechanisms

6. What is the problem? When causal inferences about “rich mental life” of an animal is made, one may be projecting own thoughts/emotions/intentions on that animal Anthropomorphism = projecting human qualities onto animals Remember that cognitive mechanisms involving internal representations are theoretical constructs inferred from the behavior of organisms This is true for both humans AND animals! We must be careful when making causal inferences and tying them to internal states when all we have is behavior as our data

7. Morgan’s Canon: Accept the lowest level of intentional explanation that works Natural selection: what matters is that the animal achieves goals such as finding food, mates, and safety. Using Morgan’s canon to choose among alternatives assumes that natural selection has always produced the lowest level intentional system that can do the job. But doesn’t answer the question of how the animal does this!

8. Why is this relevant? Functional concerns of behavioral ecology and ethology often lead to mechanistic questions -- which are the realm of cognition. Cognitive ethologists are frequently concerned with the diversity of solutions that living organisms have found for common problems. Emphasize broad taxonomic comparisons Do not focus on a few select representatives of limited taxa (we hope). Looking for general principles of behavior or cognition.

9. Behavioral ecology can inform questions of cognition Optimal Foraging Theory: maximize rate of energy intake and fitness. Example: Woodpecker takes longer on some trees than on others when foraging. Assume: adaptive, optimal, maximizing energy, maximizing fitness. Function: avoid depleted food, avoid predation, stay close to nest. Mechanism: how know depleted, what info tells bird to change behavior, how does it know where its nest is? Measure: distances between trees, prey repletion rates, prey energy, etc.

10. What about memory? Do animals show evidence of “memory” If so, do they show different KINDS of memory How are different animals’ memory similar or different: Across species In comparison to human memory How is an animal’s memory altered? What factors impact the formation of memory? What kinds of things are remembered?, How can animal memory be explained in terms of function?

11. Compare to Human memory: Kinds of Memory Reference: Information that is procedural and long term. How to dial phone Working: event specific and short term. What number to dial.

12. Matching to Sample and Language Is metacognition or metalinguistic awareness necessary?

13. Equivalence Class Three defining relations for determining equivalence: Reflexivity: generalized identity matching Matching novel stimulus to itself Symmetry Functional reversability of conditional relation If A then B; if B then A Occurs without direct reinforcement Transitivity Three stimuli: A, B, C A = B A = C Therefore, B = C

14. Equivalence Class Stimulus equivalence defined: Symbol and referents form functionally substitutable elements Relation between symbol and referent not unidirectional (reflexivity and symmetry) Deal with verbal or symbolic activity Picture of a dog = word dog = picture of a dog Many animals show stimulus equivalence: Monkeys, Chimps and bonobos Parrots and Corvids Dogs Pigeons to lesser degree Sea animals: Seals, sea lions, orcas, dolphinsw What cognitive abilities are necessary for this?

15. How test “concept formation” Concept = Problem solving strategy that is based on relations between stimuli NOT strategy based on particular aspects of individual problems Start with # of exemplars then applied to novel problems Use matching to sample Shown an exemplar Pick the matching concept from stimulus array Sameness-different-ness

16. Testing animals for Concepts Several important criteria for testing across species: Exclusion effect: novel vs. familiar Correct answer = novel stimulus Are you shaping “choose the new” or “choose the concept”? Effects of novelty: Can be disruptive Is it the stimulus or the novelty that the animal is responding to? Using large pool of stimuli helps reduce this effect

17. Pigeons: Maki and Hegvik (1980) directed forgetting Assume that updating of memory is critical Human data suggest that this depends on mnemonics Directed forgetting = cueing what to forget Do animals remember differently when directed to forget? Use MTS task again Now add a delay: DMTS

18. Procedure for Testing Pigeons: 6 pigeons in a 3 key conditioning chamber: Center key lights up white; peck it Peck would then result in one of two equally probable events: 2 sec access to grain OR 2 sec with no stimuli presented Used different delays: 6-15 seconds After the delay: 2 keys light up: Red and Green Peck to Red reinforced if trial begun with NO food but a stimulus Peck to Green reinforced if trial had begun with NO stimulus presented Had to remember first event: if correct, got food; if incorrect, got TO

19. Training Training: Group “light”: comparison stimuli omitted for trials containing the house light during delay Cue to remember : dark Cue to forget: light on Group “dark”: comparison stimuli omitted for trials containing NO house light during delay Cue to remember: Light Cue to forget: Dark Ran probe tests on last 20 days: Total of 40 Forgetting-cue and 40 Remember cue probe trials

20. Results for early trials with the Pigeons Obtained Mean percentages correct for F (forget) cue and R (remember) cues, dark and light, and short or long delays Results: Decrease in matching accuracy in Forgetting-cue probe trials relative to Remember-cue trials for both Part A and Part B training Remembered less when cued to forget! Remember-cue trials were more accurate than Forget-cue, particularly when Forget-cue was house light and not darkness

21. Experiment 2 Examined effects of cuing and the predicted time course of cueing Also examine feature positive vs. feature negative effect Method: 6 birds again Trained on basic task with no delay Trained to flashing vs. steady house light Trained to dark vs. light Added probe trials

22. Results of Experiment 2 with Pigeons Again, performance during house light as cue for forgetting was worse compared to house light as cue to remember Matching following forget cues was less accurate than following remember cues Delay decreased performance Presence of House light as forgetting cue was disruptive! (remember feature positive effect….how does this tie in?)

23. Conclusions: Cuing effects can vary with nature of to-be-remembered sample (remember the feature negative effect!). Did NOT support the rehearsal hypothesis, but appears pigeons “did something else” when prompted to forget Is this similar or different to humans? Suggests must engage in mediating behaviors to maintain remembering

24. Sea Lions and DMTS 2 female Sea lions: Rocky and Rio Procedure: All initial stimulus training = problems with 2 stimuli Novel stimuli always paired with novel stimuli Large number of stimuli used Allowed assessment of novelty effects Each comparison stimuli had an equal probability of appearing as S+ and S-: maintains conditionality (A=B or B=A) Hypothesis: Identity matching experience that is gained by completing one test will facilitate performance on subsequent tests.

25. Experiment 1 At beginning of trial: sample stimulus exposed for 4 sec, then 2 side doors opened revealing 2 choices (S+ and S-) Simultaneous conditioning Nose poke was operant response; Sr = fish Training: Exclusion phase: correct vs. familiar, familiar = S- Trial and error: all novel stimuli, trained until 90% correct Reshuffling: any stimulus could appear with any other within the concept Why reshuffling? Additional experience Dependence on context eliminated Minimize control by other unintentional stimuli

26. Experiment 1 Testing: 30 novel stimuli in 15 paired problems 4 training sessions Then test novel stimuli Assessment: Order effect: initial trial performances were about as accurate as chance (50%) Divided Test trials into 2 groups: Compared these 2 groups compared to baseline Trials 1-4 (trial 1 alone, too) Trials 5-8 Examined test groupings as pass or fail: pass = ¾ items correct

27. Results of Sea Lion MTS Training: Rio learned first problem more easily (90% or higher) But: On initial probe trials with novel stimuli, she scored only at chance (50%). With more trials her accuracy increased Reshuffling: No decrement in performance for either sea lion Showed transfer of training between stimuli Appeared to be responding according to identity relationship

28. Reshuffling: Test 1: Rio: first set NOT better than chance But further training: 90% or better Treated novel problems differently than familiar Interestingly, vocalized and touched novel stimuli more Novel stimuli appeared to disrupt Rio’s behavior Rocky: No apparent reaction to novelty of stimuli Test 1 was ambiguous Test 2 was improved But: overall, performed well on both tests In general: performed as well as during baseline Pass/fail analysis: Rio passed all Rocky passed 14/15 then 15/15

29. Experiment 2 Assess the degree to which generalization of a matching rule would occur with stimuli previously encountered in nonidentity context. Retrained sea lions on arbitrary MTS task with stimuli that they previously had extensive training on (changed the pairings, stimuli were the same as first tests) Tested on MTS using familiar stimuli from old task Same procedure, but different pairing of stimuli What was the difference: Test with familiar, not novel stimuli

30. Results of Experiment 2 with Sea Lions Pass/Fail analysis: Rocky: 10/10 for first set; 8/10 for second set Rio: 7/10 and 8/10 Overall did not obtain as many 100% test as in novel training Did show reflexivity among elements previously related only to dissimilar or nonmatching stimuli Suggests that there was some interference from previous training

31. Conclusions regarding Sea Lions Sea lions were able to transfer identity concept to novel problems in visual MTS test Why successful? Large number of exemplars Extended training Reshuffling phase allowed problems to be broken up, reducing reliance on unintentional attributes….This way, selecting only for the identity relation Habituated to novelty Individual differences were apparent: Experience “intelligence” (are there smart and dumb sea lions?) How transferable is MTS? May depend on “abstractiveness” of concept Context important: what can the abstract concept be grounded with? MTS not necessarily limited by precise context that is learned

32. DTMS and human children 12 children in 3 groups (MA 14-36 mos) Normally developing preschoolers Cognitively impaired with near typical language Cognitively impaired with no language development Stimuli: 4 conditional discriminations: If A then B If D then E If A then C If D then F Matching made up animal like figures using MTS

33. DTMS and human children Training: Presented A or D as sample, B,E or C,F as comparisons 3 stimuli presented on paper Sample at top, two choices at bottom Test: equivalence indicated by matching B and C or E and F B or E as sample with C and F as comparisons C and F as sample with E and B as comparisons Each child taught and tested individually Reward = short activity or treat Did use visual prompting Obtained interobserver agreement and reliability estimates

34. Language and kids: Results Looked at group and individual data Data graphed as percentages of unprompted correct responses in blocks of 10 consecutive trials Performance varied across 3 groups: Typical and children with cognitive impairments (CI) but with language: required fewer trials to mastery About 100 for typical; 225 for CI/language; 500 for CI/no language

35. Language and kids: Results Equivalence test: looked at Individual data Did track # of no responses made by child during each block of 10 trials: did not differ x group % of correct responding = # correct responses/total number of responses in block Results showed differences by cognitive ability AND language ability: Normal group: 84.5% correct CI/language: 78.25% CI/no language: 44.5%- very close to chance Typical and CI/language children improved across the equivalence testing phase: Normal: 77.5 to 95.5 CI/language: 69.75 to 88% CI/no language: 46.25 and 39.25%

36. Language and kids: Results Data suggest that language/symbol use may be necessary for development of stimulus equivalence in young children Not that couldn’t learn discriminations Couldn’t learn conditional discriminations under these conditions Literature shows can learn with overtraining Seems to be lack of symmetrical responding rather than inability to show transitivity Slower to learn overall May just take longer

37. Conclusions Which comes first: equivalence class learning or symbol use? Animal data suggest equivalence class Pigeon data: could do task, but not aware Sea lion data: better transitivity and symbol use Higher mammals, primates, dogs show transitivity and symbol use Is language learned or innate? Is it a process that requires multiple inputs from genetics, environment Synergistic interactions between nature and nurture? Can’t have language with equivalence class But is LANGUAGE required to discriminate complex stimuli? Answer seems to be, “depends on the type of complex stimuli”!

38. Spatial Memory Spatial memory = memory for places Why might this be important for animals? How can we test spatial memory in the laboratory? Morris Water Maze: Typically used with rats or mice Large water tank Spatial cues placed around the room (decals on walls, location of doors, windows, etc.) Placement of platforms (start and finish) are tied to different “landmarks” Data show that rats and mice do indeed use the landmarks https://www.youtube.com/watch?v=LrCzSIbvSN4

39. Spatial Memory Radial Arm Maze A maze with many arms: typically use 8 in labs Food hidden at end of the arms Examine search strategies https://www.youtube.com/watch?v=LU36985DlMk

40. Spatial Memory Can examine prospective and retrospective memory Prospective = imagining the future Retrospective = remembering the past Using radial arm maze: do rats look forward or backward? Do they remember where they have been or where they have yet to be? For first few arms: retrospective After 4-5 arms: prospective In a sense, they use whatever is less to remember! Why might spatial memory be more important for animals such as rats than concept formation?

41. Vaughan and Greene (1973): Classification of pictures by Pigeons Pigeons trained to classify slides as positive or negative Random assignment to + or _ category: No concept involved After 10 sessions, could classify 80 slides (40 + and 40-) Learned the next 80 even faster Eventually worked up to a total of 320 slides Results showed that pigeons could easily learn this classification even with no concept involved.

42. Herrnstein, 1976: Concept formation in Pigeons Wanted to see if pigeons could learn to categorize complex stimuli Three categories: Trees Water Person Found that pictures being seen for first time (novel) discriminated as well as training pictures Interestingly- similar patter of errors and correct discrimination across the pigeon subjects

43. What does this mean? Ability to discriminate open-ended classes of stimuli poses problems at two levels: Analysis of features Analysis of properties Analysis of features: Enabling subject to tell whether object is member of particular class Analysis of properties: Enabling subject to tell whether stimuli are of similar or different classes such that it renders the stimuli discriminable

44. To what were Herrnstein’s Pigeons responding ? Slides had complex composition: Too complex to be categorized alon simple common elements Rather: the slides contained a cluster of features that were more or less isomorphic-probabilistic conjunctions and disjunctions Look like semantic categories of generalization: We classify the slides on the basis of a semantic category But: are semantic labels necessary? Did the pigeons label the categories (trees, water, people) Or did the pigeons just categories on the basis of the features?

45. Does evolution play a role: Are pigeons prewired to see trees, water, people? Presence of static features can be discriminated If they are, do they have to give the trees, water or people a language label or can the pigeons categorize without language/semantic labels? More likely that pigeons are prewired to form a “schema” or prototype Examine behavior of other species to determine how behavior may be “prewired” and learned Language is not necessary to form “concepts” or categories Language may make concept labeling and categorization more efficient

46. Metamemory

47. Memory without Awareness? Pigeons can remember, but are they aware how well they remember? Metamemory Awareness of how your memory works and an awareness of how much/how well you can remember People can report state of memories, don’t know if animals can Why is reporting on memory important? Adaptive Provides functional guide to how to remember Memory monitoring = form of Memory awareness How test metamemory: Test of sensitivity to memory strength: choose whether to take a memory test Rejecting the test = less reward than taking test Used Direct test of memory (DMTS) Animals with strong memory awareness should choose to take test more often Who, besides humans, has shown metamemory Monkeys and nonhuman primates Dogs Some evidence in rats and pigeons

48. Metamemory Pigeon Experiments Pigeons show vast memory ability and strong discrimination abilities Very good at MTS and DMTS; Can classify very complex stimuli But are they AWARE of how well they remember? Experiment 1: Ask birds chose between fixed small # of pellets and varying probabilities of larger # of pellets Fixed choice= Escape: NO test, just get the smaller reward Variable = larger reward for remembered or none for miss ; size of reinforce varies and pigeon has to remember Over time all birds chose constant reinforcer and switched away from higher variable payoff No differences in memory, Just a difference in preference Suggests pigeons weren’t willing to “risk” their payoff

49. Metamemory experiments in pigeons Experiment 2: Trained on task, then tested memory: Given the option of a test or no test If chose no test got an easy discrimination task rather than time out Examined choice and accuracy during choice testing vs. forced trial testing: Predicted that if pigeons had less memory  chose easy discrimination choice when had choice Results: No memory effects: pigeons remembered regardless of forced or choice test Found longer delays = poorer performance regardless of forced or choice Pigeons still preferred to not take the test!

50. Metamemory experiments in pigeons Experiment 3: Now present choice to escape simultaneously with no escape choice Again examined forced vs. choice testing and length of delay In general, more accurate when choice test, but memory accuracy not significantly different from forced test Experiment 4: Had pigeons rate their confidence level for “answers” Trained on conditional discrimination (DMTS) Again, choice vs. forced and varied the delay interval between presentation and test Results: None of pigeons chose to gamble after an incorrect response Ambiguous choice for gambling after correct responses Accuracy dropped with longer delay intervals, but no affect on confidence

51. Summary of pigeons and metamemory Bottom line: little evidence for metamemory in pigeons, even with high accuracy for DMTS task! Can perform the task, BUT appear to be “unaware” of how strong or accurate their memory might be Unlike other higher mammals and some birds Interesting because of strong memory performance But absence of metamemory: Do not seem to be aware of how well they remember!

52. So what does this all mean? Memory is not necessarily tied to language Language or symbol use is tied to higher level cognitive tasks, but is not necessary Animals such as pigeons can learn to classify complex stimuli Are surprisingly accurate Show similar patterns of forgetting (as more to remember, more difficult to remember) But: Animals such as pigeons do not seem to have an awareness of their memories or how their memory works. Animals with greater symbolic memory seem to have greater metamemory and awareness of how their memory works.