Top of page

Neuroscience

Kanbar Hall and Druckenmiller Hall

Research Projects

Below are spotlights of recent honors projects for the neuroscience program.
Honors profile of Sydney Bonauto, Class of 2023
Sydney Bonauto '23

Thesis: "Ultrasonic vocalization playback as an affective assay at both neural and behavioral levels: Implications for understanding adversity-induced emotional dysfunction."

Abstract:

Anxiety is a common mood disorder that decreases quality of life for the many individuals diagnosed every year. However, few translational models to study the neural correlates of these disorders exist. Playback of emotionally valenced rat ultrasonic vocalizations (USVs) may be a translational model to induce and/or assess affective processing of positive and negative stimuli inactively behaving rats. Here, pre-recorded USVs at 22kHz (aversive call) and 55 kHz (appetitive call) were played to adult male and female Sprague-Dawley rats in an open field test (OFT) for 20minutes in an assessment for anxiety-like behavior. Brain tissue was stained for regional and cell specific activity. Results show that these adults were affected by playback in measures of locomotion. Neural results point to activity in the prelimbic prefrontal cortex (PL PFC),particularly of parvalbumin-expressing (PV+) interneurons as a female-specific effect of playback. In a second experiment, juvenile (Postnatal day (P)26) or adult (P47) animals raised in typical or early life adversity (ELA) conditions via maternal separation were subjected to 15 minutes of aversive 22 kHz USV playback or silence in an open field. This study showed that ELA experience led to dysregulation of affective processing particularly in juveniles (P26). Anxiety-like behaviors for a juvenile cohort persisted though 15 minutes of playback and markedly influenced ELA females when exposed to aversive playback. Young adults largely regulated behavioral output in response to playback, but ELA females exhibited a novel hyperlocomotion behavioral pattern, possibly indicating a sex-specific anxiety-like phenotype in the OFT. The PV+ neuron activity(indicated by cFos+) in PL PFC of juvenile females was increased for ELA individuals in the presence of playback, suggesting early onset of maturation of this region supported by hypervigilant, anxiety-like behavioral output. These data suggest USV playback is an affective assay of underlying sex-specific chronic anxiety states due to ELA history.

Most memorable neuroscience course: Topics in Neuroscience with Patsy Dickinson

Since graduating: I am currently a Neuroscience PhD student at Tufts University Graduate School of Biomedical Sciences in Boston, MA. I hope to continue researching mood disorders, affective circuitry, and early life adversity in rodent models.

Honors profile of Jackie Seddon, Class of 2023
Jackie Seddon '23

Thesis: "The role of neuromodulation on the pyloric neurons and the neuromuscular junction in a pattern generator-effector system."

Abstract:

Neuromodulation, the process of altering the electrical outputs of a neuron or neural circuit, allows an organism to control its physiological processes to meet the needs of both its internal and external environments. Previous work shows that the pyloric pattern of the kelp crab (Pugettia producta) stomatogastric nervous system (STNS) neurons responded to fewer neuromodulators than the Jonah crab (Cancer borealis). Since the kelp crab diet primarily eats kelp, it is possible that the movements of the foregut that control digestion may require less flexibility in functional output compared to an opportunistic feeder. To determine whether a reduced flexibility is correlated with diet, this study compared the modulatory responses in Pugettia to two other species of majoid crabs: Chionoecetes opilio and Libinia emarginata, which are both opportunistic feeders. Pooled data for this study found that Libinia and Chionoecetes responded to all twelve modulators tested.

When considering the effect of modulators on stomatogastric ganglion (STG) motor outputs, we must consider whether these modulators also alter the excitatory junction potentials (EJPs) at the neuromuscular junction (NMJ), and whether there are differences in responses across species. To test this, the dorsal gastric nerve (dgn) was stimulated while recording intracellularly from the muscle fibers of the associated gm4 muscles. The NMJ of the gm4 in Cancer borealis did not appear to be broadly modulated, as only RPCH and CabTRP showed increases in amplitude, and RPCH decreased facilitation at 5 Hz.

Most memorable neuroscience course: Neurophysiology with Dan Powell

Since graduating: I am currently a senior research technician and lab manager in the lab of Dr. Eve Marder at Brandeis University. I am working on a project investigating the expression of heat shock proteins in the STNS in response to various perturbations including high temperature and high potassium. Outside of the lab, I have been enjoying trying new coffee shops around Boston and going for runs along the Charles River! I am planning to attend a Neuroscience PhD program after my time at Brandeis. 

255 Maine Street
Brunswick, Maine 04011
 (207) 725-3000