We finally have a small sound attenuating chamber here in the lab! You may be asking, what in the heck is that thing and why is it helpful to your research?
The lab’s research centers around measuring brain responses to auditory stimuli. In order to measure auditory responses accurately, we need to place animals in a space that reduces sounds that are coming from the environment. This ensures that the recordings we make are only from sounds we introduce to the animal. With a chamber of this size, we can measure auditory brainstem responses (ABRs) which are signals we can get from electrodes placed on the scalp (or just under the skin) of animal to record impulses from areas of the brain responsible for the ability to localize sound sources. Additionally, we can put electrodes in the brain of animals while playing sound and record directly from auditory regions.
What types of things are we hoping to learn? Some of the projects in the lab that use these techniques are:
-Recording from frogs and toads that live in different environments (terrestrial, aquatic, burrowing) to see if these environments impact the brain’s encoding of sound location information.
-Measuring responses from mice with mutations that lead to autistic behaviors, such as Fragile X Syndrome, to see how their sound localization pathways are impacted.
-Working with Dr. Michael Reichert (https://reichertlab.com/) to determine if sensitivity to different auditory stimuli in Grey Treefrogs is seasonally or hormonally dependent.
-Measuring the brains of other cool animals (naked mole rats, prairie dogs, etc.) to determine how they process sound information that may lead to insights into how the brain works and what specializations different species have in this auditory pathway.
Stay tuned for more lab updates and hopefully publications etc. related to this work!
*Video below shows a recording from the brain of an anesthetized gerbil. Sound you hear is the neuron firing in tune with a low frequency sound we are playing the gerbil. You can see as I unplug sound to one ear, the firing stops and that as I change the frequency of the sound I am playing to the gerbil, the firing (the squiggly lines on the recording) go away. This suggests the neuron I am recording from is both frequency and sensitive to sound played only to one ear.
https://www.dropbox.com/s/wtry8acgwqz6fif/MNTB%20recording%20flipped.mp4?dl=0
Elizabeth McCullagh Lab 