Learning new skills as you age is challenging due to inefficient motor skill acquisition. Brain plasticity plays a key role.
Is it possible to rewind the clock on this age-related decline?
Why do older adults struggle to stay focused?
A new study from the Max Planck Institute for Biological Intelligence offers a glimpse into this possibility. Scientists mainly focused on zebra finches, songbirds known for their elaborate vocalizations.
Zebra finches learn their songs during a critical developmental time, and after that, their songs are hard to change. Inhibitory interneurons play a role in closing this learning period, but it’s unclear if changing them can reopen the ability to learn new songs.
Zebra finches have a critical period for song learning within their first 90 days of life. After this window closes, their brains become less flexible, and inhibitory neurons slow further learning.
How neurons form long-term memories?
Scientists switched off these inhibitory neurons in adult zebra finches using pharmacology and a cell-type specific optogenetic approach. What they found is remarkable.
Scientists manipulated inhibitory neuron activity in a premotor area of adult zebra finches beyond their critical period. When given new songs, birds with altered brain cells added new sounds to their usual songs. By lifting inhibition in a premotor area during sensory experience, scientists reintroduced vocal plasticity and expanded their repertoire without affecting their existing songs.
Age-related cognitive decline may be reversible, study
“We observed an expansion of the adult animals’ vocal repertoire that was previously thought impossible,” says Fabian Heim, the study’s lead author.
“This discovery extends far beyond the realm of birdsong. The brain’s capacity for learning may be far more resilient than previously thought. Similar learning windows exist in humans, affecting everything from language acquisition to social development. If scientists can identify and manipulate the mechanisms that control these critical periods, it could open doors to new therapies for neurodegenerative diseases and injuries that impair learning.”
Journal Reference:
- Heim, F., Mendoza, E., Koparkar, A. et al. Disinhibition enables vocal repertoire expansion after a critical period. Nat Commun 15, 7565 (2024). DOI: 10.1038/s41467-024-51818-4
