In a first for “sonogenetics,” researchers control mammalian cells with sound

LA JOLLA—Salk scientists have engineered mammalian cells to be activated using ultrasound. The method, which the team used to activate human cells in a dish and brain cells inside living mice, paves the way toward non-invasive versions of deep brain stimulation, pacemakers and insulin pumps. The findings were published in Nature Communications on February 9, 2022. Read more »

Decoding the chemistry of fear

Ask a dozen people about their greatest fears, and you’ll likely get a dozen different responses. That, along with the complexity of the human brain, makes fear—and its close cousin, anxiety—difficult to study. For this reason, clinical anti-anxiety medicines have mixed results, even though they are broadly prescribed. In fact, one in six Americans takes a psychiatric drug.

A team of investigators from the Salk Institute uncovered new clues about the mechanisms of fear and anxiety through an unlikely creature: the tiny nematode worm. By analyzing the responses of worms exposed to chemicals secreted by its natural predator and studying the underlying molecular pathways, the team uncovered a rudimentary fear-like response that has parallels to human anxiety. Such insights may eventually help refine prescriptions for current anti-anxiety drugs and enable the development of new drugs to treat conditions like PTSD and panic disorder. Read more »

Worms have teenage ambivalence, too

Salk Institute scientists studying roundworms suggest that, in both worms and humans, adolescent brains mature to stable adult brains by changing which brain cells they use to generate behavior. Teen worm brains drive wishy-washy behavior that allows them to stay flexible in an uncertain world, while adult worm brains drive efficient behavior. The discovery provides insight into the underlying drivers of neurological development that could help better understand the human brain and disease. Read More »

Brain Circuit Shows How Dopamine Controls Animal Behavior

Salk scientists discover a learning circuit in worms that gives clues to human behavior.

If you had 10 chances to roll a die, would you rather be guaranteed to receive $5 for every roll ($50 total) or take the risk of winning $100 if you only roll a six?

Most animals, from roundworms to humans, prefer the more predictable situation when it comes to securing resources for survival, such as food. Now, Salk scientists have discovered the basis for how animals balance learning and risk-taking behavior to get to a more predictable environment. The research reveals new details on the function of two chemical signals critical to human behavior: dopamine–responsible for reward and risk-taking–and CREB–needed for learning.
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