Analyzing neural responses to vocalizations

Jeffrey Wenstrup, Ph.D., Sharad Shanbhag, Ph.D., and Mahtab Tehrani, Ph.D. (NEOMED)

Research Area
Vocalizations reflect our emotions. As we listen to another’s vocal signals, we respond by assigning them a meaning determined by the vocalization itself, our previous experience, and our own emotional state. This in turn affects the way that we respond to a person’s vocal signals—by our posture, facial gestures, movement, and speech. Our goal is to understand how the brain shapes our responses to these vocal signals.
Brain regions of interest: Our focus is on the amygdala, a brain center that integrates sensory inputs with information about our previous experiences and our internal state. It then assesses the meaning of new sensory information and “decides” on the appropriate behavioral responses. We also study the auditory centers that send information to the amygdala about social vocalizations.

Our models We use bats and mice as models to study these processes. Bats are sound experts that use vocalizations to both communicate and to catch prey and navigate through echolocation. Mice are acoustic generalists that integrate acoustic and other sensory information during social interactions. Both models provide valuable insights into the mechanisms underlying acoustic communication and emotions.

Current Project
We have a large data set of recordings of the neural responses in the amygdala to vocalizations. Analysis of these data uses custom MATLAB programs that we have developed in the lab. We are looking for an undergraduate with programming experience to aid in developing new visualization and analysis code for this data set. The student would preferably have experience programming in MATLAB, but experience in other programming languages (Python, C) is also acceptable. The student would be expected to work with the existing MATLAB code and develop new code in MATLAB. Experience in using git and Github is also desirable.

Click here for more information about Dr. Wenstrup’s lab

‘I’m too freaked out to hear you!’ How early-life stress affects auditory perception and the brain

Dr. Merri Rosen, Kate Hardy, Matthew Sunthimer (NEOMED)

Research Area
It’s well-known that hearing problems in kids may cause later trouble with understanding complex sounds, such as speech in a place with a lot of background noise. But our lab is the first to show that early-life stress (ELS) during development can cause similar problems. Many labs have studied the effects of ELS on the development of brain regions responsible for attention, learning, and related psychopathologies. Our work has found that auditory information is not being encoded properly before it even reaches these higher-level brain regions. This is important, because children who grow up in low-socioeconomic, high stress environments are at risk for later problems with speech perception. Discovering what is going wrong mechanistically will help prevent and remediate these problems.
We’re funded by the National Institutes of Health to study the neural mechanisms that can cause stress-induced deficits in auditory perception. It turns out that ELS may be a particular problem when kids have ear infections that cause intermittent hearing loss – our data show that early hearing loss and stress together are much worse than either one alone! We use an animal model that is well-established in auditory research – the Mongolian gerbil – because gerbils hear well at frequencies that humans use, unlike mice or rats.


Current Project
We are looking for a student to assist in testing gerbils on behavioral tasks to measure their auditory perception and learning abilities, and quantify animal behavior using video analysis

Students will:

  • Receive training in experimental techniques used widely across research fields in biology and neuroscience
  • Learn how to apply critical thinking to big problems in neuroscience
  • Opportunities to attend weekly journal clubs on Auditory Neuroscience in the Hearing Research Group at NEOMED, and related seminars given by neuroscience faculty from around the world

Click here for more information about Dr. Rosen’s lab