Unit 2-4 Notes

Classical Conditioning and Biological Predispositions

• Agonists include cocaine, amphetamine, and methylphenidate, while antagonists include chlorpromazine and haloperidol.
• Dopamine (DA) neurons in the ventral tegmental area (VTA) in the midbrain are crucial, as measured by Schultz during conditioning.
• The unconditioned stimulus (US) is drops of juice, and the unconditioned response (UR) is lick, while visual stimulation serves as the conditioned stimulus (CS).
• Higher DA levels indicate a stronger response and more surprise to the US, reflecting the detection of learning by DA.
• Goal-directed behaviors, such as sign tracking and goal tracking, are observed, with dopamine levels increasing only during sign tracking.
• DA is released from the VTA to the nucleus accumbens (NAcc) in the reward pathway.
• The homeostatic hypothesis of learning suggests that DA in the VTA is activated when learning uses current or past knowledge, and the prediction error signal turns on the response system.
• Biological predispositions are inborn, and the separation of time between the US and CS is critical, with a preference for a few seconds of delay.
• Equipotentiality is challenged by taste aversion, demonstrating that the CS does matter.
• The CS is sometimes context-dependent, as seen in flavor-illness learning and conditioned taste avoidance.
• Drugs of abuse, such as amphetamine, cocaine, and morphine, produce conditioned place preference and conditioned taste avoidance but do not produce conditioned disgust in rats.
• The preparedness of a species influences conditioning, and counter-prepared associations and instinctual drift are observed. Determinants of a conditioned response (CR) include complexity, avoidance behavior, and appetitive behavior.

Associative Learning and Classical Conditioning

• Ivan Pavlov discovered conditioned reflexes through original experiments with digestion on dogs
• Classical conditioning involves unconditioned stimulus (US) like food, conditioned stimulus (CS) like a bell, unconditioned response (UR) like salivation, and conditioned response (CR) like salivation
• The process involves the bell being rung before food is given, leading to salivation occurring with the food, eventually causing salivation when the bell rings
• S-S* learning involves the CS and US, with conditioned excitation making the CS an excitor of behavior and conditioned inhibition predicting the absence of a US
• Tests of conditioned inhibition involve summation, retardation of acquisition, and CS- testing
• Conditioned responses can be autonomic (e.g., heart rate), motivational (e.g., emotions), or somatic (e.g., movement)
• Conditioning preparations include eye blink conditioning (simple reflex) and fear conditioning in mice
• Place conditioning involves administering a drug as the US and observing the rat's response in different compartments
• Alternatives to CS-US conditioning include pseudo-conditioning, sensitization, S-R learning, and postconditioning devaluation
• CS-CS associations involve second order conditioning, sensory preconditioning, and the strength of conditioning
• Laws of association include the frequency, intensity, novelty, contiguity, and contingency of CS-US association
• Different types of conditioning include delay, trace, simultaneous, and backward conditioning, with a focus on the proper timing and sequence of CS and US for effective conditioning