New findings on dopamine and learning. Researchers at the Leibniz Institute of Neurobiology (LIN) have shown in a recently published study that a reduction in dopamine production in the brain alters learning in a surprising way. Their study showed that a reduced dopamine level improves the association of stimuli with punishment at unusually long time intervals, while learning is worse with immediate punishment. These results could provide new insights into the understanding of psychiatric disorders such as schizophrenia, in which dopamine plays a key role.
Magdeburg/Germany, March 24, 2025 Dopamine, an important chemical messenger in the brain, is crucial for linking stimuli to rewards or punishments. ‘Our results were surprising because they show that lower dopamine levels improve learning ability when conditions are actually unfavourable. In contrast, learning is impaired when conditions are actually favourable,’ explains Prof. Bertram Gerber, the lead scientist of the study. ‘If the time interval between stimulus and punishment is too long, a reduced dopamine level improves the ability to learn, while an immediate punishment is processed less effectively.’
Methodology: Inhibition of tyrosine hydroxylase
These findings were obtained by specifically inhibiting tyrosine hydroxylase, an enzyme necessary for dopamine production, in the brains of the flies. ‘With lower dopamine levels, the flies make connections between events that would not be made under normal circumstances. In return, they overlook obvious connections,’ adds PhD student Fatima Amin, whose research led to these findings.
Significance of the results
The discovery that reduced dopamine levels can alter learning in such complex ways emphasises the central role of this neurotransmitter in learning causal relationships between events. These findings could provide new approaches to understanding disorders associated with changes in dopamine production, such as schizophrenia.
The Leibniz Institute of Neurobiology is a leading international brain research centre dedicated to the study of brain processes at the neurobiological level. Its research focuses on understanding the fundamental principles of learning and memory as well as changes in brain networks during illness. In addition to the causal understanding of brain function and dysfunction, the LIN addresses socially relevant topics in medicine, health, technology and education. The LIN’s research concept embodies the realisation, loosely based on Leibniz, that the brain is an organ that is ‘filled with past and full of future’.
Original publication:
Compromising Tyrosine Hydroxylase Function Extends and Blunts the Temporal Profile of Reinforcement by Dopamine Neurons in Drosophila
Fatima Amin, Christian König, Jiajun Zhang, Liubov S. Kalinichenko, Svea Königsmann, Vivian Brunsberg, Thomas D. Riemensperger, Christian P. Müller and Bertram Gerber
Journal of Neuroscience 12 March 2025, 45 (11) e1498242024; doi.org/10.1523/JNEUROSCI.1498-24.2024
Weitere Informationen:
(https://doi.org/10.1523/JNEUROSCI.1498-24.2024)
ImageSource
LIN, Robin Ritter, Fatima Amin is doing her doctorate at the Leibniz Institute of Neurobiology in Magdeburg on the role of dopamine in learning.