Theoretical Approaches and Questions in Operant Conditioning Psychology 3306

Responses and reinforcers How important are responses and reinforcers? Thorndike and Skinner would say that it is essential Tolman said ‘ umm, not completely Cognitive maps Latent learning

So you don ’ t need a reinforcer? Perhaps it strengthens the S-R bond, but is not necessary Maybe it becomes part of a representation? Colwill and Rescorla, 1985 Chain - > water Lever - > food Food - > poison

That sound you hear is Skinner spinning in his grave Rats won ’ t press the lever! Therefore, the response and reinforcer have been connected, but not directly It seems that associations are made between all three parts of the three term contingency

Are there 2 types of learning? Yes, operant and classical No, it is all associative learning What a stupid question….

Pushing the limits Heart rate conditioning Biofeedback Not always successful

So what is a reinforcer? Some event that increases the likelihood of…. ENOUGH! Maybe it is need or drive reduction? Premack ’ s ideas Is food the reinforcer, or is it the act of eating?

Premack ’ s principle Given 2 responses arranged in an operant- conditioning procedure, more probable behaviors will reinforce less probable behaviors; less probable response will not reinforce more probable ones

Premack (1963) - study in Cebus monkeys Lever Pressing (L) : highest probability Door Opening (D) : medium probability Plunger Pulling (P) : lowest probability reinforces D; L reinforces P; P does NOT reinforce either D or L, etc. “ Premackian reinforcers ” : activities that act as reinforcers (reading, playing) Useful (and less costly) in token economies than object-based reinforcers

Applications Mitchell & Stoffelmayr (1973) use Premack ’ s principle in schizophrenics Reinforcement items like candy, cigarettes, etc. usually not effective in schizophrenic patients Sitting is a highly probable behavior in negative-symptom schizophrenics (catatonia, social withdrawal) therapists made sitting contingent on doing small amount of work or activity; improved their negative symptoms In unruly nursery-school children, high probability behaviors (running around, screaming) made contingent on low probability behaviors (sitting quietly, paying attention)

Behavioural economics Open economies Closed economies Elasticity of demand And behavioural ecology

Stimulus Control Relationship between S and R Reynolds (1961) - Attention in the pigeon 2 pigeons reinforced for pecking to compound stimulus of white triangle on red background projected on response key rate of pecking was then observed in each subject to a white triangle and a red background singularly

Why do you get a gradient? Sort of the study of generalization and discrimination How do you get data? – Probe trials – Test phases – Both done in extinction Is it a property of the nervous system? – Pavlov – Hubel and Wiesel

Perhaps it is learning? Lashley and Wade figured it was how the animal was trained Borne out by Jenkins and Harrison ’ s work Non differential Presence absence Explicit training

Duck you Peterson (1960) and his ducklings, only saw yellow They did not show gradients with colour! Oops Probably depends on the modality and the species being tested really Or, could be relational Kohler and his chickens

Gonzalez, Gentry, & Bitterman (1954) - chimpanzee had to pick among 9 squares of varying sizes Squares 1,5, & 9 presented, subject reinforced for choosing # 5 (intermediate size) on test trial chimp reinforced no matter which square chosen if given 4, 7, & 9 relational theory says subject will choose # 7, absolute theory says subject will choose square closest # 5 ( # 4) subjects usually chose the intermediate size square of whichever three squares were presented

Peak Shift

OK, so that is odd Why does that happen? Excitatory gradient Inhibitory grandient As the Violent Femmes would say, you gotta add it up

Bird brain is not an insult Concept learning Natural needed? How long lasting Delius (1982) Honig and Stewart (1988) The field of comparative cognition really grew out of much of this stuff