Learning and Behaviour Learning –Enduring change in behaviour –Due to experience –How something is done Behaviour –Procedures and actions performed –Learning –Non-learning –What is done

Types of Learning Habituation/sensitization Classical conditioning Operant conditioning Observational/vicarious

Adaptation Changing conditions Time scales Learning only one type of adaptation

Innate Behaviours

Evolved Environmental change Re: Learning –Roots in innate behaviours –Parallels Homeostasis, reflexes, tropisms, modal (fixed) action patterns

Evolutionary Theory Voyage of the Beagle ( ) On the Origin of Species (1859) Artificial, natural, and sexual selection Adaptation to environment

Natural Selection Variation, inheritance, selection Differential reproductive success No intelligent design Level of the individual Change over generations

Examples: Physical Evolution Australopithecus afarensis (400cc), Homo erectus (1200cc), Homo sapiens (1400cc ) Skull Bipedalism

Examples: Behavioural Evolution Cooperation (e.g., food sharing, child rearing) Pair bonding Altruism

Homeostasis Internal balance of the body Drives Regulatory drives

Control System Comparator Reference input Actual input Action system Output Feedback system (closed-loop system) Response lag

Blood Salinity Comparator Output Eat peanuts! Action System Actual input Eat more peanuts! Drink water! Reference input

Reflexes Stereotypic movement patterns Reliably elicited by appropriate stimulus Survival benefit

Example: Grasping in Infants Humans, other primates

Example: Eyeblink Stimulus (e.g., airpuff) Eyelid closes

Example: Limb Retraction Sharp rock, hot surface, etc. Fast muscle contraction Pulls limb away

Reflexes Rapid response Simple neural pathways Sensory neuron, interneuron, motor neuron

Reflex Arc muscle sensory neuron interneuron motor neuron ?

Tropisms Movement, or change in direction, of the entire animal Jacque Loeb –Geotropism

Geotropism

Types of Tropisms Kinesis –Movement random with respect to stimulus Taxis –Non-random (directed) movement with respect to stimulus

heat source testing arena Kinesis Movement in a random direction hot cool mediumfast slow

Taxis Movement that bears some relationship to the location of a stimulus testing arena heat source hot cool

The Models Kinesis –Random turn –Set move length –No more than 180° turn –Movement speed variable (fast, medium, slow) Taxis –Turn so as to move away from heat –Set move length –No more than 180° turn –Movement speed fixed

Modal (Fixed) Action Patterns Originally “fixed”; variable to some degree Species specific, often state dependent Sign stimulus (“releaser”) activates a dedicated neural system To completion in sequence

Graylag Goose Rolls displaced egg near its nest back with beak Sign stimulus: displaced egg Remove egg during sequence watch?v=vUNZv-ByPkUhttp:// watch?v=vUNZv-ByPkU

Stickleback Bruno Cavignaux / Biosphoto gasterosteus-aculeatus-aculeatus/image-A23078.html

Supernormal Stimuli Extreme version of sign stimulus Size, colouration, etc. Preference sometimes detrimental

Beetles on the Bottle Gwynne & Rentz (1983) Male Jewel beetles (Julodimorpha bakewelli) Colour and reflection of bumps on bottle as supernormal stimuli for female beetle

General Behaviour Traits Behavioural traits strongly influenced by genes Not the same as Modal Action Patterns –GBTs more plastic than MAPs –No single sign stimulus e.g., Species Specific Defense Reactions –Freeze, flee, fight –Mouse vs. bear

Environmental Interaction Not strictly genetically controlled Susceptible to conditioning e.g., twin studies

Behavioural Influence Selective breeding studies Artificial or natural selection e.g., morphine addiction in rats e.g., Silver foxes 2CF3Yhttp:// 2CF3Y

Habituation and Sensitization Simplest form of Learning

Habituation and Sensitization Changes reflex response Learning without new axons/synapses Temporary effect at existing synapse –E.g., less neurotransmitter released from axon terminal

Habituation Decease in a response following repeated stimulus presentation Note: note everything that results in a decrease in response is habituation Sensitization Increase in a response following repeated stimulus presentation

Example: Banana Slug Habituation Eyestalk retraction Touch back Record time until eyestalks are fully re- extended

Results Slug eyestalk re-extension times –Trial 1: 23 sec –Trial 2: 12 sec –Trial 3: 10 sec –Trial 4: 7 sec –Trial 5: 3 sec –Trial 6: 1 sec Trial Time (sec.)

Example: Rat Sensitization 1. Gentle touch, no response 2. Painful shock, flinch 3. Gentle touch, flinch

HabituationSensitization GeneralizationLessMore Length of effectLongerShorter Rate of relearning Quicker than initially Habituation and Sensitization Generalization: treat other stimuli like learned stimuli Discrimination: distinguish other stimuli from learned stimuli

Spontaneous Recovery Post habituation or sensitization Return to original level of responding Due to passage of time

Limits of Natural Selection Adaptation relatively slow Generally not helpful during a lifetime Select best adapted individuals from each generation Evolutionary time lag Variation within species

Learning: Evolved Modifiability Selective pressure Learning –Going beyond innate behaviour patterns All animals Evolutionarily selected for Allows individuals to adapt to rapid environmental change

Nature and Nurture Long debate British Empiricists vs. Nativists Not “either/or,” but “both” Genes and environment constantly interact Biology and experience both shape an organism’s behaviour patterns

The Ability to Learn A by-product of both heredity and experience e.g., rats reared in complex environments e.g., educational aids for infants