How does the brain learn from negative experiences?
Balázs Hangya and his team studied deep brain inhibitory cells and observed that when these cells were blocked, the mice did not learn from the negative stimuli they received. The significance of their discovery is reflected in the fact that their work has been accepted for publication in the journal Nature Communications.
Learning is one of the most important activities of our lives, and we still don't know enough about the processes taking place in the brain. A significant part of the memory processes is controlled by a deep brain nucleus called the basal forebrain. In articles published last year and the year before, Balázs Hangya and his team reported that the cells that regulate the coordination of neurons for memory storage and the timing of memory storage and retrieval within the brain are located in the medial septum, the part of the basal forebrain closest to the nose.
Their recently published work examined the middle area of the basal forebrain behind the medial septum, or Broca's diagonal bundle. The researchers found that the inhibitory cells located here infiltrate a significant part of the limbic system responsible for emotion and memory regulation, and their studies, in collaboration with Gábor Nyiri's group, also revealed that these inhibitory cells receive information from brain areas involved in processing negative experiences. The cells showed rapid and strong activation when the experimental mice received negative feedback, i.e. punishment, during learning, and inhibiting their activity meant that the mice did not learn from the negative feedback, continuing to respond to the punishment stimuli with reward-seeking behavior. Further studies have also shown that artificial activation of inhibitory cells alone is not sufficient to induce avoidance behavior, however, they are necessary for animals to associate a negative value with the stimuli they receive.
Hangya and his colleagues believe that the neural pathway under investigation may be important for eliciting and maintaining the attention required for learning, at least when learning from negative experiences.