Blocking

Definition

Blocking is a phenomenon in classical conditioning where the presentation of one conditioned stimulus (CS) prevents the acquisition of a second CS-unconditioned stimulus (US) association. In other words, if an organism has already learned to respond to one CS, the addition of a new CS will not result in that new CS eliciting a conditioned response.

5 Must Know Facts For Your Next Test

1. Blocking demonstrates that learning is not just a passive process of associating stimuli, but an active process of making predictions and updating those predictions.
2. Blocking occurs because the first CS already predicts the US, so the addition of a new CS does not provide any new information to the organism.
3. Blocking is considered evidence that classical conditioning involves higher-order cognitive processes like prediction and expectation, not just simple stimulus-response connections.
4. Blocking has been observed in a variety of species, including humans, and across different sensory modalities.
5. The strength of the blocking effect depends on factors like the salience of the first CS, the number of CS-US pairings, and the temporal relationship between the CS and US.

Review Questions

• Explain how the phenomenon of blocking demonstrates that classical conditioning involves more than just simple stimulus-response associations.
  • Blocking shows that classical conditioning is an active process of making predictions and updating those predictions, rather than just a passive process of associating stimuli. If an organism has already learned to respond to one conditioned stimulus (CS), the addition of a new CS will not result in that new CS eliciting a conditioned response. This is because the first CS already predicts the unconditioned stimulus (US), so the new CS does not provide any new information. This suggests that classical conditioning involves higher-order cognitive processes like expectation and prediction, not just basic stimulus-response connections.
• Describe the factors that can influence the strength of the blocking effect.
  • The strength of the blocking effect can be influenced by several factors. The salience of the first CS is important, as a more salient or prominent CS will more strongly predict the US and lead to a stronger blocking effect. The number of CS-US pairings also matters, as more pairings will strengthen the association and the blocking effect. Additionally, the temporal relationship between the CS and US can affect blocking, with stronger blocking occurring when the CS and US are closely paired in time. Other factors like the sensory modality of the stimuli and the species being studied can also influence the strength of the blocking phenomenon.
• Evaluate how the blocking effect challenges traditional views of classical conditioning and supports the idea that it involves higher-order cognitive processes.
  • The blocking effect challenges the traditional view of classical conditioning as a simple, passive process of stimulus-response association. Instead, it suggests that classical conditioning involves active, higher-order cognitive processes like prediction, expectation, and learning. By demonstrating that the addition of a new CS does not result in a conditioned response if an organism has already learned to respond to a different CS, blocking shows that learning is not just about forming basic connections between stimuli. Rather, it is a dynamic process where the organism is constantly updating its predictions and expectations based on the information available. This supports the idea that classical conditioning engages more complex mental processes, such as making inferences, forming hypotheses, and adjusting behavior based on previous learning. The blocking effect, therefore, is a key piece of evidence that classical conditioning is a sophisticated, cognitive phenomenon, not just a simple reflex.

Related terms

Conditioned Response (CR): The learned response that occurs after the conditioned stimulus (CS) is paired with the unconditioned stimulus (US).

Extinction:

The decrease or disappearance of a conditioned response when the conditioned stimulus is presented without the unconditioned stimulus.

Latent Inhibition:

The reduced ability to learn a new association between a stimulus and an outcome if the stimulus has been pre-exposed without the outcome.