Jessica Cardin facts for kids

Jessica Cardin is an American neuroscientist who studies the brain at Yale University School of Medicine. Her lab looks closely at how tiny parts of the brain, especially in the visual cortex (the part that helps us see), change how they work depending on what we're doing. For example, how does your brain see things differently when you're super focused versus when you're relaxed? They also use what they learn to understand brain problems and diseases.

Early Life and Discoveries

When Jessica Cardin was in ninth grade, she did an experiment at home. She used mice to see if there were differences in how male and female mice learned new things.

She then went to Cornell University for her college degree in biological sciences. At Cornell, she joined the lab of Timothy DeVoogd. There, she studied how songbirds learn to sing. She mapped out parts of the brain important for singing in female canaries. Her work helped show how certain brain cells connect to areas involved in song learning. They found that some neurons (brain cells) that help with singing also get direct sound input.

After graduating from Cornell in 1997, Cardin went to the University of Pennsylvania for her advanced studies in neuroscience. She worked with Ted Abel, studying how memories are stored in the brain. She helped write a paper about how memory can be stopped or reduced in different animals.

In 2000, Cardin joined Marc Schmidt's lab. She went back to studying songbirds, like she did in college. This time, she looked at how the birds' brain activity for hearing changed depending on what the bird was doing. For example, how did their brains react to sounds when they were awake versus asleep?

Cardin finished her PhD in 2004. She then stayed in Philadelphia for her postdoctoral research at the UPenn Medical School. She worked with Diego Contreras and learned about electrophysiology. This is a way to record the electrical activity of single brain cells. She used this method to study the visual cortex of cats and understand how it processes what they see.

She finished this training in 2009. But from 2007 to 2009, she also trained at the Massachusetts Institute of Technology (MIT). There, she started using a new tool called optogenetics. This tool uses light to control brain cells. She began to find new ways to use optogenetics to study and record brain activity.

How Brain States Change Hearing

During her PhD studies, Cardin explored how sensory processing (like hearing) changes depending on different brain states. These states include being sedated, awake, or very excited. She found that what an animal is doing greatly affects how its auditory neurons (hearing brain cells) fire.

For example, when songbirds are asleep, the neurons in a brain area called the HVC fire more. They also respond strongly to the bird's own song. But when the birds are awake, these neurons fire in a more varied way and don't show the same strong preference for the bird's own song. She also found that being excited or alert actually made the HVC less responsive to sounds. This suggested that other brain systems must be working to help birds hear better when they are awake.

Brain Areas and Behavior

After finding that the HVC brain area changes with behavior, Cardin discovered that another area, called the nucleus interfacialis (NiF), also changes with behavior. By using medicines to either stop or boost the activity of the NiF, Cardin found that the NiF is a key place where information about behavior comes together. It then sends this information to the HVC, telling it how to respond to sounds based on the bird's state.

Later, Cardin showed that specific types of neurons in the NiF, called noradrenergic neurons, are responsible for how the NiF responds to brain states. Overall, her graduate work showed that these noradrenergic neurons in the NiF are very important for sending information about brain state during vocal learning in songbirds.

How We See: Gamma Waves

In her postdoctoral work, Cardin studied gamma oscillations in the primary visual cortex of cats. Gamma oscillations are like fast brain waves. She looked at different types of cells in the visual cortex. She found that while both types of cells fired in gamma rhythms, only some cells showed a specific response to what they were seeing. Cardin suggested that these cells might help spread these visual gamma waves throughout the brain.

After this, Cardin and her team confirmed something called "gain modulation" in the visual cortex. Gain modulation means that the strength of a brain cell's response changes, but what it responds to (its "selectivity") does not. Cardin's team found that this gain modulation changes very quickly. It depends on what the animal is seeing at that moment and how brain connections are working.

Using Light to Study the Brain

Cardin then had a short postdoctoral position at M.I.T.. There, she learned about optogenetics. She used this new technology in creative ways to expand on her earlier findings. Cardin helped show how fast-spiking interneurons (a type of brain cell) can boost gamma oscillations when they are activated by light. They found that these cells responded strongly when stimulated at certain frequencies. However, other types of brain cells, called pyramidal neurons, responded better at lower frequencies.

This work showed that scientists could use optogenetics to control brain activity in living animals. After this, Cardin and her team created a method to both stimulate neurons with light and record their activity at the same time. This new technology allowed scientists to ask very specific questions about what different groups of brain cells do.

Career at Yale

In 2010, Jessica Cardin joined Yale University School of Medicine. She became an assistant professor in the Department of Neurobiology. In 2012, she also became a member of the Kavli Institute for Neuroscience at Yale.

Cardin's lab at Yale studies how brain circuits in the cortex (the outer layer of the brain) work. They want to understand how brain cells and their connections change to adapt to different situations. This helps us understand how we see things and how our brains drive our actions. Her lab also uses this knowledge to study how problems in these brain circuits might lead to diseases.

Besides her lab work, Cardin is an advisor for the Brain Science Mindscope Advisory Council at the Allen Institute. She has also been very involved in organizing the COSYNE Conference, a big meeting for brain scientists, since 2009.

How Brains Stay Flexible

Cardin is very interested in how the brain can do so many different things without needing more and more specialized brain cells. Brain cells can quickly change and adapt to different environments and how alert you are. Cardin and her team looked at how brain activity changes when moving between different awake states.

They found that when you are very alert, brain cells fire less on their own. But their response to visual information becomes much clearer. Their findings showed that brain cells act differently in different states. The brain's ability to change its activity patterns is affected by both how alert you are and whether you are moving.

In another study, Cardin and her team used a special imaging technique to look at three different groups of neurons in the visual cortex. They wanted to see if these groups sent unique information about what was seen to other parts of the brain. They found that specific groups of neurons process and send visual information in different ways to help guide behavior.

More recently, Cardin and her team studied the role of special neurons called VIP interneurons in controlling brain circuits. They removed a key signaling part, called ErbB4, from these VIP neurons. They saw that this caused problems with how the brain processed sensory information. It also messed up the brain's ability to adapt to different states, which they had shown was important earlier.

Interestingly, these problems in brain function showed up during adolescence, even though the ErbB4 was removed earlier in development. This suggests that some problems in brain development might not appear until later in life. This could help us understand how many brain diseases develop.

Awards and Honors

• 2018 Allen Institute Distinguished Seminar Series
• 2015 Smith Family Award for Excellence in Biomedical Research
• 2014 McKnight Scholar Award
• 2012 Alfred P. Sloan Fellowship
• 2011 NARSAD Young Investigator Award
• 2010 Klingenstein Fellowship Award in Neuroscience
• 2005 Kirschtein Individual Postdoctoral NRSA Research Fellowship
• 2004 Flexner Award for Outstanding Neuroscience Dissertation Research - University of Pennsylvania
• 1996 Howard Hughes Undergraduate Scholar - Cornell University