How our brains motivate themselves to continue learning is a complicated subject matter which is still not completely understood by scientists. It is known that the ‘reward chemical’ dopamine is involved as a way of providing us with motivation, but our understanding of how is limited. Some research has also suggested that forgetting might actually help us to learn sometimes.
One theory is known as reward-prediction-error. If a reward is expected then the brain will not release dopamine, but if a reward is unexpected then the brain will fire out dopamine. However, some studies have shown that this is not always the case – that dopamine can remain high even when trying to achieve predictable rewards as a form of motivation. It is now thought that our brains switch between these two modes, releasing quick shots of dopamine for unexpected rewards and smaller amounts of sustained dopamine for longer-term motivation.
A recent study conducted by Ayaka Kato and Kenji Morita, from the University of Tokyo, and published in ‘PLOS Computational Biology’ attempted to look deeper into the role of dopamine in the learning process. To do so, they created a puzzle which had to be solved through a series of decisions. They also programmed the reward-related connections in the brain to gradually weaken during the experiment so that they could measure the effects of forgetfulness.
They then ran the trial a few hundred times. Against expectations, increasing forgetfulness actually quickened the time in which the puzzle was solved. It seemed that forgetfulness significantly increased motivation to keep on achieving routine targets. This builds on earlier research which had found that lower levels of dopamine can decrease our motivation.
The researchers are hopeful that in the future the results could be helpful in treating neurological conditions which are related to dopamine, stating ‘This could potentially be related to neuropsychiatric and neurological disorders, in particular, Parkinson’s disease, which is characterized by motor and motivational impairments that are suggested to be independently associated with dopamine. Better understanding of the dynamic nature of biological value-learning systems will hopefully contribute to clinical strategies against these diseases.’
Further research in laboratory conditions will be needed before any concrete conclusions can be drawn, but the study conducted by Ayaka Kato and Kenji Morita could be the first step towards better treatment for a range of neurological disorders such as Parkinson’s disease.