Cognition and Foraging

1. Cognition and Foraging

2. Classic framework for explaining animal behavior • 4 levels of explanation (Tinnbergen) • Phylogeny: relatedness among groups of organisms • Ontogeny: origin and the development of an organism from the fertilized egg to its mature form • Survival value: how behavior aids in survival • Mechanisms of foraging behavior: what are the behavior mechanisms for foraging in an organism • Cognitive psychologists focus on proximate causes of behavior within the organism • Proximate: cause-effect relations? • What are the foraging behaviors? • Where did they originate from? • What is their purpose? • What is the cause-effect relationship between an individual foraging behavior and the environment?

3. Classic framework for explaining animal behavior • Cognition = set of psychological mechanisms by which organisms obtain, maintain, and act on information about the world • Include many “behaviors” • Perception • Attention • Learning • Memory • Reasoning • With animals: cognition must be considered unconscious behavior • Why cognition? • Allows foragers to identify/exploit patterns in environment • Predict future behavior of environment, other organisms and themselves • Cognitive abilities affect survival fitness • Cognitive abilities appear to evolve

4. Perceiving the environment • Sensation = conversion of environmental energy into biological signal that preserves relevant patterns • Transduction of physical energy into neural impulses • Broad range of sensory abilities • Across species • Within species • Individuals

5. Feature Integration • Must be able to “make sense” of the pattern • Separate figure from background • Letters from slide • Moth from tree branch; a leaf walker insect; camouflage • Several important effects: • Pop-out effect • Feature search • Conjunctive search: forager must inspect items that share features with the target(distracters) • Attention: focusing limited information processing capacity • Factors affecting feature integration • Texture and pattern • Color • Different capabilities across species, strains, individuals

6. Search image • Tinbergen: • Birds collecting insects for young • When new prey became available (and was abundant), slowly switched over • Didn’t “recognize” new insect at first • Had to develop a search image • Why important? • Must have search image to engage in foraging • Sequential priming effects may occur • What your search image IS affects what you look for • Suggests learning is involved, not just innate ability

7. Stimulus Generalization • Stimuli may share similar features • More overlap = more generalization • Can discount minor differences when foraging for prey/food • Shows FLEXIBILITY in foraging/search behavior • Can alter generalization and discrimination • Training • Experience • Discrimination/generalization may help form categories • Appear to be some natural categories • Species specific • in humans: feature detectors that recognize male/female, the human face, emotions • In animals, may have innate categories for prey/predators • Experience may alter these categories • Interaction between innate and experience • Interested in different capacities • Across species • Across individuals • Within individuals as setting varies

8. Quantity of Prey • Relative numerousness: a sense of numbers • Ability to process many versus one or few or many • Animals show ability to count • Can compare one set to another • Humans can subitize: perceive size of small groups • Recognizing small sets by their pattern • Can animals? Possibly and probably • Alex the parrot • Some primates • Other animals?

9. Pavlov’s Contribution • Ivan Pavlov • Russian physiologist: Studied salivation • 1901: discovered and wrote about classical conditioning • Found that his dogs reacted to both his presence and the time of day for feeding/experimentation • Researched this: • Measured amount of salivation during baseline: • Present food to dogs • Measure slobber • Then added a predictive stimulus: a Bell • Presented the BellFood • Measured slobber to see if dogs would begin to slobber to the bell

12. Labeled each part of these events: • Unconditioned stimulus or US: • The stimulus that automatically elicited the behavior (usually innate) • E.g., the food elicited the slobber • Unconditioned response or UR • The behavior that is automatically elicited • Unlearned; often reflexive • Conditioned stimulus or CS: • The stimulus that predicts the US • Is a learned (thus conditioned) stimulus • Conditioned response or CR: • The behavior that occurs to the CS • Often very similar to the unconditioned response • Occurs because the CS predicts the US

13. Classical Conditioning Procedure

14. Characteristics or Parametersof Classical Conditioning • Relationship between UR and CR • The UR and CR are not always identical! • Often are similar, or in similar family of behavior • Can be opposite: compensatory response • If predicted to go up, you respond by going down! • See this with drugs: • Morphine = lower BP, heart rate, feeling of cold, less pain • CR to morphine= higher BP, HR, feel hot, more pain • What could be predictive CS for morphine?

15. Characteristics or Parametersof Classical Conditioning • Strength of CR • Gradually increases with trials • E.g., slobber more after each CS-US pairing • Monotonically increasing curve: levels off • Reaches an asymptote: some maximum amount of CR • Why?

16. Characteristics or Parametersof Classical Conditioning • Extinction and Spontaneous recovery • Extinction: If stop CS-US pairing (CS nothing), then the CR will also fade away • Again, must be unlearned, or habituated! • Spontaneous recovery • Sometimes, when conditions are similar to CS, the animal shows the CR • Unpredictable; almost as if they “suddenly remembered” • More likely to occur when animal is stressed, tired, hungry, etc.

17. Characteristics or Parametersof Classical Conditioning • Relearning: • Relearning is faster than original learning • True if extinction occurred AND if just haven’t had the experience for a while • Important for drug, fear reactions! • Generalization and discrimination: • Generalization: CR will occur to stimuli that are similar to the original CS • Discrimination: Can train the animal so the CR only occurs to very specific CSs • Higher Order Conditioning: • Chaining of CSs: e.g., CS3CS2CS1US • Respond most to CS1; least to CS3

18. Special Cases • Second Order conditioning: Chaining of CSs • CS3CS2CS1UR • Conditioned inhibition • CS1US • CS1+CS2 NO US • produces inhibitory response • Learn NOT to respond because CS predicts non-occurence of US • Latent inhibition similar: • Play a tone frequently, never pair with a CS • Now try and train that CS with a US • No learning- learned it was meaningless • Sensory preconditioning: • Stimulus 1 and Stimulus 2 occur together • Train CS1 US; may get reaction to CS2 because it was previously associated with CS1

19. More special cases of CC • Blocking • One stimulus BLOCKS learning to second CS • Learn CS1 US • Add CS1+CS2US • Test CS2 no CR • Overshadowing • Use two CSs; one is more powerful than other • Get more conditioning to more powerful CS, less conditioning to weaker CS

20. Assumptions of R-W model • Helpful for the animal to know 2 things about conditioning: • what TYPE of event is coming • the SIZE of the upcoming event • Thus, classical conditioning is really learning about: • signals (CS's) which are PREDICTORS for • important events (US's) • model assumes that with each CS-US pairing 1 of 3 things can happen: • the CS might become more INHIBITORY • the CS might become more EXCITATORY • there is no change in the CS • how do these 3 rules work? • if US is larger than expected: CS = excitatory • if US is smaller than expected: CS= inhibitory • if US = expectations: No change in CS • The effect of reinforcers or nonreinforcers on the change of associative strength depends upon: • the existing associative strength of THAT CS • AND on the associative strength of other stimuli concurrently present

21. The Equation • Yields an equation: Vi =αißj(Λj-Vsum) • Vi = amount of learning on a given trial • αi =salience of the CS • ßj =salience of the US • Λj=Total amount that can be learned • Vsum= how much has been learned so far

22. Acquisition • first conditioning trial: CS = light; US= 1 ma Shock • Vsum = Vl; no trials so Vl = 0 • thus: Λj-Vsum = 100-0 = 100 • -first trial must be EXCITATORY • BUT: must consider the salience of the light: αi = 1.0 and learning rate: ßj = 0.5 • Plug into the equatio: for TRIAL 1 • Vl = (1.0)(0.)(100-0) = 0.5(100) = 50 • thus: V only equals 50% of the discrepancy between Ajan Vsum for the first trial • TRIAL 2: • V1 = (1.0)(0.5)(100-50) = 0.5(50) = 25 • Vsum = (50+25) = 75 • TRIAL 3: • V1 = (1.0)(0.5)(100-75) = 0.5(25) = 12.5 • Vsum = (50+25+12.5) = 87.5 • TRIAL 4: • V1 = (1.0)(0.5)(100-87.5) = 0.5(12.5) = 6.25 • Vsum = (50+25+12.5+6.25) = 93.75 • TRIAL 10:Vsum = 99.81, etc., until reach ~100 on approx. trial 14 • When will you reach asymptote?

23. Biological boundaries of behavior • Old-school behaviorists emerged as a reaction against the Structuralists. • Rejected biology in error • The equipotentiality principle explains their position: • The choice of any CS, US, R, Sr or P is arbitrary • Any CS can be paired with any US • Any response can be governed by any Sr or P • Once a reinforcer or punisher, always and for everyone in the organism’s class • Biology is irrelevant; anything can be learned

24. Obviously, they were WRONG! Let’s look at evidence that shows this: • Garcia effect or conditioned taste aversion • Learned helplessness • Preparedness learning or behavior systems models

25. Garcia Effect orConditioned Taste Aversion • Grp I: Tasty Water--> Nausea • Good Conditioning • Grp II: Bright Noisy Water-> Shock • Good conditioning • Grp III: Tasty Water--> Shock • No conditioning • Grp IV: Bright Noisy water--> Nausea • No conditioning

26. A “biological boundary” may explain this phenomenon: • Look at the TYPE of stimuli that are being used: • Categorize each as an internal or external event • Grp I: Tasty Water--> Nausea • InternalInternal • Grp II: Bright Noisy Water-> Shock • ExternalExternal • Grp III: Tasty Water--> Shock • InternalExternal • Grp IV: Bright Noisy water--> Nausea • External Internal • Can’t learn ACROSS modalities very well!

27. Important Properties of Taste Aversion • One trial conditioning • General phenomenon: most species show it • Tolerates long delay • Novel stimuli condition more readily than familiar stimuli • Occurs differently for different species: • quail: color of food • monkeys: texture • rats: taste and smell • In social animals- can transmit stimulus socially

28. Uses • Humans: • dietary restrictions and smoking cessation programs • (but will switch brands and tastes) • Can develop CTA with Chemotherapy- must watch pairing good food with nausea • Most important use: Wildlife Management: • Coyote management • Wolf management • Bear management

29. Memory • Memory is organized • Chunks • For humans: 7 +/- 2 • Allows us to remember more • Most forgetting is INTERFERENCE • Two items interfere with one another • Not that forgotten, but not strong enough association • Memory takes work • Working memory • Long term memory • Animals also have both working memory and long term memory • Is important for performance: must remember what it is you are to do, remember the reinforcement schedule

30. How locate food? • Spatial orientation • Many cues to cache location • Local cues or landmarks • Directional cues • Compass marks • Beacons • Frames of reference • Relative position in array: What is it next to? • Gradients: • Mental “maps” • Darker gradient vs. lighter gradient • Rocky vs. grassy • Landmarks • Ability to perceive and recognize unique objects • Use to orient within an array • Template matching in honey bees • Birds and mammals use three dimensions • Height, width, depth • Unique features of landmarks themselves • Spatial associations between landmarks • Triangulate to find them

31. Cognitive maps • By using spatial orientation, gradients, landmarks, animals form cognitive maps • Tolman first to discuss this concept • Jacobs and Schenk (2003) cognitive map = two submaps: • The bearing map: directional cues • Sketch map: positional cues • Two independent neural circuits within hippocampus subserve these maps • Parallel map theory: animals need both sketch and bearing maps to create cognitive maps • has been suggested that only bird and mammals have this capability

32. Food Hoarders have different Spatial cognition • Must • Store food • Remember location • Protect it from competitors and predators • Must maintain WHERE and HOW MUCH is stored over long time periods • Use several interesting cues • Special spatial encoding • Encode cache sites as unique places on global map • Caches must be stable • Each cache must have unique coordinates • Unique sites prevent interference forgetting

33. Food Hoarders have different Spatial cognition • Must have strong spatial memory • Time not as important • Must find cache in terms of location in space • Evidence that hoarding animals have must stronger spatial memory than non-hoarding animals • Must have memory of caching events • Must remember where cache was • How much is in cache • When you put it there and if you’ve retrieved it!

34. Social learning • Social animals learn from one another • Local enhancement: no direct contact between individuals • Social facilitation: presence of conspecifics may affect motivation/arousal of an observer • Imitation and emulation: mimic what the other animal does • Strong evidence of social learning in animals

35. How obtain food? • Operant or instrumental conditioning • RSr • Imitation • Teaching • What is commonality: • Make a response, and get food • Not have to be direct experience • Adults may teach younger members of group • Insight: • Kohler’s chimp • Why and how? • Appears that must have all behavioral components in place • Is novel combination of behavior • Tool use: • Ability to make a new “tool” to help gain access to food • Requires means-end analysis or cause-effect relationships • Strong evidence in nonhuman primates, social animals

36. Tying it all together • We have groups of foraging rats • Individual animals have individual capacities • Sensory • Cognitive • Experience • social interactions, rank in group • Group has unique capacities as well • Depends on individuals • Group social experiences • We can examine how groups of foraging rats: • Finds food • Divides up the share of food • Detects changes in payoff rate at given foraging site (F1 vs. F2) • Also examine how an individual foraging rat • Finds food • Gets his share of the food • Detects changes in payoff rate at given foraging site • Need means/model to do this: The Generalized Matching law and Ideal Free Distribution • GML: Describes the behavior of a foraging animal • IFD: describes behavior of group • Does group = individual1+individual2+individual3+individual4+individual5/5 • Does group = f(individual1,individual2,individual3,individual4,individual5) • How do individuals act to form the group behavior?