St. Jude Children’s Research Hospital scientists have discovered that curtailing activity of the neuromodulator adenosine extends the critical period of auditory learning in mice and offers promising results for humans
“By disrupting adenosine signaling in the auditory thalamus, we have extended the window for auditory learning for the longest period yet reported, well into adulthood and far beyond the usual critical period in mice,” said corresponding author Stanislav Zakharenko, M.D., Ph.D., a member of the St. Jude Department of Developmental Neurobiology. “These results offer a promising strategy to extend the same window in humans to acquire language or musical ability by restoring plasticity in critical regions of the brain, possibly by developing drugs that selectively block adenosine activity.”
The auditory thalamus is the brain’s relay station where sound is collected and sent to the auditory cortex for processing. The auditory thalamus and cortex rely on the neurotransmitter glutamate to communicate. Adenosine was known to reduce glutamate levels by inhibiting this neurotransmitter’s release. This study also linked adenosine inhibition to reduced brain plasticity and the end of efficient auditory learning.
Researchers used a variety of methods to demonstrate that reducing adenosine or blocking the A1 adenosine receptor that is essential to the chemical messenger’s function changed how adult mice responded to sound.
Much as young children pick up language simply by hearing it spoken, researchers showed that when adenosine was reduced or the A1 receptor blocked in the auditory thalamus, adult mice passively exposed to a tone responded to the same tone stronger when it was played weeks or months later. These adult mice also gained an ability to distinguish between very close tones (or tones with similar frequencies). Mice usually lack this “perfect pitch” ability.
Researchers also showed that the experimental mice retained the improved tone discrimination for weeks.
“Taken together, the results demonstrated that the window for effective auditory learning re-opened in the mice and that they retained the information,” Zakharenko said.
Among the strategies researchers used to inhibit adenosine activity was the experimental compound FR194921, which selectively blocks the A1 receptor. If paired with sound exposure, the compound rejuvenated auditory learning in adult mice. “That suggests it might be possible to extend the window in humans by targeting the A1 receptor for drug development,” Zakharenko said.
Zakharenko and his colleagues also linked the age-related decline in ease of auditory learning to an age-related increase in an enzyme (ecto-5’-nucleotidase) involved in adenosine production in the auditory thalamus. Researchers reported that mature mice had higher levels than newborn mice of the enzyme and adenosine in the auditory thalamus. Deletion of this enzyme returned the adenosine level in adult mice to the level of newborn mice. Therefore, researchers are currently looking for compounds that target ecto-5’-nucleotidase as an alternative approach for extending the window of auditory learning.
The Latest on: Extending the window of auditory learning
- Lane County educators say the governor must reduce class sizes and address behavioral and mental health issues on December 16, 2018 at 5:17 am
Mental health needs and the lack of resources to allocate toward them, including counseling, was closely tied with the need for more support for behavioral outbursts, student violence and disrupted le... […]
- The Rise of Knowledge Economics on December 13, 2018 at 4:22 am
This last data set was the flour we needed to create empirical measures of knowledge, extending Romer’s ideas ... the math showed that there was a narrow window of opportunity when it was ... […]
- Blue Sky Science: How do we hear? on December 12, 2018 at 8:44 pm
Then tiny bones inside the middle ear end up vibrating and pushing on a small window. This then gets a ... the cells and send information to the auditory nerve or cochlear nerve. […]
- Learning styles: each brain absorbs information differently on December 12, 2018 at 8:07 am
“Back in the day when my dad was learning math, he had an abacus (or counting frame) and he would slide the beads,” said Taraman. “It was a very tactile, visual, even auditory because you ... […]
- Watching the brain for wrong turns on December 11, 2018 at 12:58 pm
Advances in stem cell biology and a new appreciation of the self-organizing powers of developing brain tissue have allowed researchers to create 3-D clusters of living brain that open a new window ont... […]
- Wish Book 2018: Sowing the seeds of community, healthful living in East San Jose on December 7, 2018 at 6:02 am
Click to share on Facebook (Opens in new window) Click to share on Twitter (Opens in new ... by asking who likes vegetables and who likes to cook with their parents, extending an invitation for them t... […]
- The Little Drummer Girl episode six recap: an explosive and satisfying finale on December 2, 2018 at 2:00 pm
When someone walks into a restricted area with a briefcase crammed with semtex you might expect amateur dramatics to go out the window ... Learning that Charlie was in direct contact with master bombe... […]
- Window into the Peninsula Watershed on December 1, 2018 at 5:33 am
Extending from trailheads at Skylawn Memorial Park in San ... “I think people actually get a learning experience as well as a recreational experience, which is always a good thing,” she said. Fournet ... […]
- Microsoft looks to the cloud to make Windows 10 safer for enterprise users on June 27, 2017 at 6:00 am
To stay ahead of these threats, the company is doubling down on its existing security efforts, but in addition, it’s now also pushing ahead with new initiatives that emphasize cloud intelligence with ... […]
- Microsoft is extending Azure IoT to the edge of the network on May 10, 2017 at 2:02 pm
IoT Edge can run on Windows and Linux and on devices as small as a Raspberry Pi with only 128MB of memory. The Microsoft services that can run on these devices include Azure Machine Learning, Stream A... […]
via Google News and Bing News