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Yossi Zeliger/TPS-IL on 8 September, 2024
Brain’s ‘Mental Tug-of-War’ Opens New Possibilities for Behavioral Therapy
Jerusalem, 26 December, 2024 (TPS-IL) -- Israeli scientists have uncovered a previously unknown aspect of how the brain learns and forms memories, with a study that could reshape our understanding of how humans learn. The findings open the door to new possibilities for behavioral therapy treating learning disorders.
Tel Aviv University researchers found that the brain cannot simultaneously learn through two prominent forms of conditioning known as classical and operant. Instead, the brain actively prevents both types of memories from forming at the same time, resolving any conflict by prioritizing one over the other.
Classical conditioning is when someone learns to associate two things, such as a dog learning to salivate when it hears a bell because it expects food. Operant conditioning is when someone learns through rewards or punishments, like a child cleaning their room to get a treat or avoiding punishment. In simple terms, classical conditioning is about automatic reactions, while operant conditioning is about learning from the results of those actions.
For years, scientists believed that these two forms of learning worked together in the brain without interference.
However, a study, led by Professor Moshe Parnas and PhD student Eyal Rozenfeld from the Laboratory for Neural Circuits and Olfactory Perception, discovered that the brain is not equipped to handle both types of conditioning simultaneously, particularly when they lead to conflicting behaviors. The research was recently published in the peer-reviewed Science Advances journal.
“You can think of the brain as engaging in a ‘mental tug-of-war’. If you focus on learning through your actions, the brain blocks the formation of automatic associations. This helps avoid confusion but also means you can’t learn two things simultaneously,” Parnas explained.
The researchers tested this theory on fruit flies, whose simpler brain structures allow for easier study. In the experiment, the flies were conditioned to associate a specific odor with an electric shock. In classical conditioning, the flies learned to freeze in place when they smelled the odor, anticipating the shock. Conversely, when operant conditioning was applied, the flies learned to flee from the odor to avoid the shock.
However, the scientists found that the flies could not successfully learn both behaviors at the same time. When both types of conditioning were introduced together, the flies failed to show any meaningful response to the odor, effectively blocking both types of learning.
This phenomenon could have broader implications for human learning. In a situation where a person is taught to fear a smell through classical conditioning, leading them to freeze in place — while at the same time learning through operant conditioning to avoid the same smell by fleeing — the brain must choose which behavior to enact. Attempting to follow both paths simultaneously leads to confusion and inefficiency.
The research also opens the door to new possibilities for treating learning disorders. Conditions like ADHD or Alzheimer’s, which involve difficulties with memory formation, could benefit from a deeper understanding of how the brain navigates these competing learning systems. It could also lead to improvements in behavioral therapy such as addiction treatments or behavior modification.
“By understanding how memories are formed and prioritized, we might be able to develop new treatments to help individuals with such conditions,” Rozenfeld said.
