Neuroscience and Neurobiology Commons^™

Temporal Interference Stimulation Effectively Reduces Parkinsonian Beta Band Activity In A Computational Model Of The Basal Ganglia Network, Anna Stolle

25th Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2026)

Parkinson’s disease (PD) is a progressive neurological disorder characterized by degeneration of dopaminergic neurons, leading to impaired motor function and disrupted basal ganglia activity. One of the most effective treatments is deep brain stimulation (DBS), which targets deep brain regions to restore abnormal firing patterns. However, DBS requires invasive surgery to implant electrodes, posing surgical risks and limiting accessibility. This has driven interest in non-invasive alternatives that achieve similar therapeutic outcomes. Transcranial temporal interference stimulation (tTIS) is a non-invasive technique delivering two high-frequency currents through scalp electrodes. These currents overlap to produce a low-frequency "beat" capable of reaching deep structures …

Transcranial Temporal Interference Stimulation Modulates Spike Timing Of Subthalamic Nucleus Neurons In A Computational Neuron Model, Kimberly Maldonado

25th Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2026)

The established treatment for Parkinson’s disease is deep brain stimulation (DBS), an effective but invasive procedure requiring surgical implantation of electrodes. Transcranial temporal interference stimulation (tTIS) is a novel, noninvasive technique with potential to target deep brain regions. It applies two high-frequency currents with a slight offset through scalp electrodes, producing a low-frequency envelope that may modulate neuronal activity where the fields overlap. The subthalamic nucleus (STN) is the favored DBS target in advanced Parkinson’s disease. While tTIS has been studied in humans, animals, and generic neuron models, no work has examined tTIS on optimized models of STN neurons. We …

The Role Of Brain Injury In Neural Proliferation And Neuronal Migration In Adult Zebrafish, Matthew Czmer, Ashley Trainor, Carmen Casper

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

Traumatic brain injury (TBI) is increasing in prevalence, with around 1.5 million people in the United States sustaining a head injury every year. Neural death following TBI contributes significantly to neurological dysfunction and, in extreme cases, death. Adult zebrafish prove a unique and advantageous model of study as they are capable of de novo neural regeneration (i.e., neurogenesis) following brain injury. While it is known that robust cell proliferation occurs in the ventricular zone (VZ) of the telencephalon of adult zebrafish, it is unknown whether these newly-generated cells and their migration aid in the process of neural repair after TBI. …

Modeling Dopaminergic Loss In The Zebrafish Olfactory System, Lexus Putt, Samantha Groenwold, Ted Lockett, Nathaniel Vorhees

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

Zebrafish provide an ideal model to study neurodegenerative diseases and regenerative processes as they present neurogenesis and a high degree of neuroplasticity throughout their lifespan. It has been suggested that dopamine has an important role in regulating olfaction. We aimed to study the structural and functional effects of dopaminergic loss in the olfactory system. We injected 6-hydroxydopamine (6-OHDA) int the ventricular zone of adult zebrafish at the interphase between the olfactory bulbs and the telencephalon to target dopaminergic neurons in the olfactory bulb.Then, we assessed dopaminergic neural loss, markers of inflammation, morphological changes of olfactory axons, and synaptic connections. Olfactory …

Retrograde Degeneration Of The Olfactory Epithelium Following Neurotoxic Lesioning In Zebrafish, Sophia A. Farbarzhevich, Riley G. Checkley, Mackenzie T. Williams, Rachel J. Mast

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

Parkinson’s Disease (PD), a neurodegenerative disease that deteriorates dopaminergic neurons in the substantia nigra, is characterized by movement deficits, sleep disturbances, mental deficits, and hallucinations. About 95% of those with PD experience olfactory dysfunction or loss of the sense of smell. Prior research found evidence of retrograde degeneration in animal models of PD, which occurs when axons degenerate proximal to the neural injury itself, beginning in the axon terminals and proceeding to the cell body. Although dopaminergic retrograde degeneration has been observed in PD models, it is unknown if this contributes to some non-motor PD’s symptoms, such as olfactory loss. …

Fishing For Answers: Studying Hypoxia's Effects On The Zebrafish Olfactory Epithelium, Madelyn Yakes, Skylar Dewitt, Gracie Hill

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

Hypoxia, i.e. low oxygen, is a physiologically damaging condition found in many health conditions such as ischemic stroke, sleep apnea, asthma, etc. Additionally, decreased dissolved oxygen levels in aquatic environments occur as a result of climate change. Zebrafish offer an excellent model to study hypoxia due to extensive neuroplasticity and injury-induced cell proliferation, which allows them to recover lost function in the central nervous system (CNS). We have shown that olfaction (i.e., the ability to smell), decreases in response to hypoxic exposure in adult zebrafish. Thus, it is important to study the structural abnormalities underlying this loss of smell. Olfactory …

Unveiling Sensory Gaps: A Study On Zebrafish Alanine Taste Blindness And The Consequential Neurotoxic Impact On Dopaminergic Neurons In Motor Regions, Samantha Groenwold, Mackenzie Korff

23rd Annual A. Paul and Carol C. Schaap Celebration of Undergraduate Research and Creative Activity (2024)

Parkinson’s Disease (PD) is a neurodegenerative disorder characterized by deficits in motor functions including loss of coordination and hypertonia. Dopaminergic (DA) neuronal death is found in the substantia nigra and reward centers of the brain in PD patients. Smell loss is also associated with patients with PD as DA neurons are found in the Olfactory Bulb (OB), the brain structure that processes odor signals. We use zebrafish as a model to study neurodegenerative diseases, including PD, as they can regenerate neurons throughout their lifespan. We have established a model to study DA loss in the zebrafish olfactory system. To do …

Role Of Neuroinflammatory Response On Cell Proliferation Following Neurotoxic Lesioning In Zebrafish, Sarah Heinowski, Nathaniel Vorhees, Nathan Koorndyk, Helen Dodge

22nd Annual Celebration of Undergraduate Research and Creative Activity (2023)

Parkinson's Disease (PD), a neurodegenerative disorder characterized by dopaminergic neuronal loss and motor impairment, affects roughly 1 in 500 people. Interestingly, olfaction loss, the loss of smell, is prevalent in over 95% of those with PD. Zebrafish provide a unique model to study neurodegenerative diseases, including PD, as they possess the unique ability to regenerate neurons (i.e., neurogenesis) throughout their lifespan. Contrary to mammals in which inflammation often has negative associations with neural injury recovery, inflammatory response within zebrafish is thought to have a key role in this regenerative capability. Thus, we aimed to inhibit the inflammatory response and investigate …

Neurodegeneration And Neuroinflammation In The Olfactory Bulb Of Zebrafish Following Acute Hypoxia, Skylar Dewitt, Evan Thomas

22nd Annual Celebration of Undergraduate Research and Creative Activity (2023)

Hypoxia, the lack of sufficient oxygen in tissues to sustain bodily functions, has a deleterious effect on physiological and behavioral health. Unlike mammalian brains, which are restrained in their capacity to recover following damage and hypoxic injury, zebrafish are an excellent model to study exposure to hypoxia due to substantial neuroplasticity mechanisms within their brain. Specifically, the olfactory bulbs (OBs) display high neuroplasticity and neurogenesis (i.e., generation of new neurons), making it a useful model to study neural responses under stressed environmental conditions such as hypoxia. Here, we establish a new paradigm of hypoxic exposure in zebrafish to uncover the …

Expression Of Olfactory-Induced Anxiety Behaviors Following Hypoxia Treatment In Adult Zebrafish, Cassidy Larson, Luke Horsburgh, Cameron Houck, Skylar Dewitt

22nd Annual Celebration of Undergraduate Research and Creative Activity (2023)

Exposure to hypoxic conditions leads to neural loss of function or death in the nervous system of mammals. Zebrafish, given their sophisticated neuroregenerative abilities, are able to survive low-oxygen conditions with fewer consequences. These capabilities are crucial for the olfactory system of zebrafish, as their olfactory epithelium is directly exposed to damage and toxins in the environment. Given that olfaction allows for critical behaviors such as foraging, mating, predator detection, and non-visual perception of dead fish, possessing functional olfactory sensation is vital to survival. Cadaverine is a chemical compound that mimics putrescine, the scent of decaying flesh. This scent induces …

Dopaminergic Synapse Loss In 6-Ohda Lesioned Zebrafish, Grace Stalions, Heather Van Dort, Gabriella Taylor

22nd Annual Celebration of Undergraduate Research and Creative Activity (2023)

Parkinson's disease is a neurodegenerative disorder caused by degeneration of dopaminergic neurons, and an early symptom of Parkinson's disease is olfactory dysfunction. A common animal model used in Parkinson's disease research is zebrafish because of their unique neuro-regenerative ability, which is particularly in their olfactory bulb. In order to create a model of the early stages of Parkinson's disease we injected zebrafish with the neurotoxin 6-hydroxydopamine (6-OHDA) to induce the degeneration of dopaminergic neurons in the olfactory bulb. Olfactory system recovery post 6-OHDA injection has been recorded in previous literature, but the state of synaptic dopaminergic synapses post-injection has not …

Effect Of Delaying Hca Exposure On The Development Of Manic/Depressive Behaviors In Sprague Dawley Rats, Eden Comer, Rachel Mast, Natalie Olander, Mackenzie Williams

22nd Annual Celebration of Undergraduate Research and Creative Activity (2023)

Bipolar disorder (BD) is a neuropsychological disorder that is characterized by cyclical periods of depressive and manic behaviors. The Chase lab is focused on developing a reliable animal model for BD in order to characterize the critical neurophysiological and neurochemical changes that trigger BD. Previous studies in the lab have shown that daily injection of rat pups from postnatal day 3 through 19 (P3-P19) with homocysteic acid (HCA) leads to the development of a mixed manic and depressive state after puberty. These behaviors can be reversed by treatment with lithium and involve changes in gene expression in the prefrontal cortex …

Exploring The Relationship Between Bipolar Disorder, Alcohol Use, And Obsessive Compulsive Disorder In The Hca Animal Model, Erick Alvarado, Ayanna Bailey, Sabrina Blank, Lindsey Boltz, Corine Lafrenier, Molly Poel

21st Annual Celebration of Undergraduate Research and Creative Activity (2022)

An estimated 4.4% of U.S. adults experience bipolar disorder at some point during their lifetime. While the prevalence of bipolar disorder is similar among males and females, it is becoming increasingly obvious that symptoms and comorbidities of the disorder can vary widely between men and women. Recent research has shown that men diagnosed with bipolar disorder are more likely to exhibit alcohol use disorders and obsessive compulsive behaviors while women have a higher incidence of panic disorder comorbidity. In order to develop effective treatment for the disorder, it is important to use an animal model that reflects these sex-dependent differences. …

Early Prenatal Exposure To Homocysteic Acid Leads To Alterations In Behavior And Gene Expression That Are Consistent With Bipolar Disorder, Kelly Bosis, Gabriella Taylor, Anna Lunderberg, Stephanie Simko

21st Annual Celebration of Undergraduate Research and Creative Activity (2022)

We have previously demonstrated that early post-natal exposure of rat pups to the NMDA receptor agonist, homocysteic acid (HCA) from P3-P21 leads to the development of mixed manic/depressive behaviors following puberty. The manic behaviors are effectively reversed by lithium treatment, and the depressive behaviors are reversed by acute ketamine treatment. Thus, HCA appears to induce a bipolar-like phenotype in rats. The goal of this study was to determine whether HCA exposure also induces gene expression changes that are consistent with a bipolar phenotype. Microarray analyses were performed on tissue obtained from the prefrontal cortices of saline- and HCA-treated rats at …

The Effect Of Electrolytic Lesions Of Superior Colliculus On Circadian Rhythms And Anxiety-Like Behavior In Rats, Alondra Villanueva, Gonzalo Moya, Bradley Dixon, Mariah Dingman

19th Annual Celebration of Undergraduate Research and Creative Activity (2020)

Circadian rhythms are physiological oscillations that allow organisms to maintain homeostasis. Circadian disruption can lead to negative health implications such as cardiovascular disease, hypertension, anxiety, depression, and even cancer. (AASM, 2005; Shields, 2002). Several brain structures modulate circadian rhythms, including the suprachiasmatic nucleus (SCN), and the intergeniculate leaflet (IGL), but very little is known about the role of the superior colliculus (SC). Here, we focused on how the SC modulates circadian rhythms and anxiety-like behaviors in diurnal species. Sprague Dawley (SD) rats (N = 18) were used in this study; nine rats experienced electrolytic lesions of the SC, while nine …

The Influence Of Hsv-1 Infection On Circadian Rhythms And Behavior In Mice, Lauren Evert, Kevin Catalfano, Victoria Gardner, Anna Lunderberg

19th Annual Celebration of Undergraduate Research and Creative Activity (2020)

Herpes simplex virus 1 (HSV-1) infection is a lifelong viral infection that affects approximately half of the human population (McQuillan et al., 2018), yet little is known about its neurological effects. There is correlational evidence that infection with HSV-1 can induce cognitive decline and increased anxiety behaviors (Harris & Harris, 2015; Steel & Eslick, 2015; Tarter, Simanek, Dowd, & Aiello, 2014). In addition, HSV-1 may be associated with disruptions to circadian rhythms because HSV-1 is associated with chronic fatigue syndrome (Bond & Dinan, 2006), the time of HSV-1 infection impacts the viral replication (Edgar, 2016), and HSV impacts CLOCK machinery …

Developing Outreach Events That Impact Underrepresented Students: Are We Doing It Right?, Andrew J. Gall, Peter J. Vollbrecht, Tristan Tobias

Faculty Publications

Many outreach programs share the common goals of serving underrepresented groups in STEM and improving public attitudes toward science. To meet these goals, scientists must find ways to both reach the appropriate audience and communicate the importance of science in meaningful and accessible ways. This requires careful consideration of the outreach method being used. Two common outreach methods include in‐school visits (scientist in the classroom) and science fairs or open houses. Here, we compare the effectiveness of these two outreach methods in meeting the goals of reaching underrepresented students and/or students with less initial interest in science. We have found …

Hydrogen Peroxide Triggers An Increase In Cell Surface Expression Of System XC− In Cultured Human Glioma Cells, Leah A. Chase, Mary Verheulen Kleyn, Natasha Schiller, Abby Goltz King, Guillermo Flores, Sasha Balcazar Engelsman, Christina Bowles, Sara Lang Smith, Anne E. Robinson, Jeffrey Rothstein

Faculty Publications

System x_c⁻ exchanges extracellular cystine for intracellular glutamate across the plasma membrane of many cell types. One of the physiological roles of System x_c⁻ is to provide cystine for synthesis of the antioxidant glutathione. Here we report that hydrogen peroxide (H₂O₂) triggers the translocation of System x_c⁻ to the plasma membrane within 10 min of the initial exposure. Specifically, we observed a three-fold increase in ³⁵S-L-cystine uptake following a 10 min exposure to 0.3 mM H₂O₂. This effect was dose-dependent with an EC₅₀ for …

Functional And Anatomical Variations In Retinorecipient Brain Areas In Arvicanthis Niloticus And Rattus Norvegicus: Implications For The Circadian And Masking Systems, Dorela D. Shuboni-Mulligan, Breyanna L. Cavanaugh, Anne Tonson, Erik M. Shapiro, Andrew J. Gall

Faculty Publications

Daily rhythms in light exposure influence the expression of behavior by entraining circadian rhythms and through its acute effects on behavior (i.e., masking). Importantly, these effects of light are dependent on the temporal niche of the organism; for diurnal organisms, light increases activity, whereas for nocturnal organisms, the opposite is true. Here we examined the functional and morphological differences between diurnal and nocturnal rodents in retinorecipient brain regions using Nile grass rats (Arvicanthis niloticus) and Sprague-Dawley (SD) rats (Rattus norvegicus), respectively. We established the presence of circadian rhythmicity in cFOS activation in retinorecipient brain regions in …

Melanopsin-Containing Iprgcs Are Resistant To Excitotoxic Injury And Maintain Functional Non-Image Forming Behaviors After Insult In A Diurnal Rodent Model, Garrett M. Fogo, Dorela D. Shuboni-Mulligan, Andrew J. Gall

Faculty Publications

Intrinsically photosensitive retinal ganglion cells (ipRGCs) are critical for the light signaling properties of non-image forming vision. Melanopsin-expressing ipRGCs project to retinorecipient brain regions involved in modulating circadian rhythms. Melanopsin has been shown to play an important role in how animals respond to light, including photoentrainment, masking (i.e., acute behavioral responses to light), and the pupillary light reflex (PLR). Importantly, ipRGCs are resistant to various forms of damage, including ocular hypertension, optic nerve crush, and excitotoxicity via N-methyl-D-aspartic acid (NMDA) administration. Although these cells are resistant to various forms of injury, the question still remains whether or …

Let It Rest: Sleep And Health As Positive Correlates Of Forgiveness Of Others And Self-Forgiveness, Loren Toussaint, Andrew J. Gall, Alyssa Cheadle, David R. Williams

Faculty Publications

Objective: The present study examined forgiveness of others, self-forgiveness, sleep, and health in a nationally representative sample of United States adults. It was hypothesised that sleep would mediate the associations of forgiveness of others and self-forgiveness with health.

Design: A nationally representative survey of 1,423 United States adults.

Main Outcome Measures: Measures included forgiveness of others, self-forgiveness, sleep quantity, sleep quality, psychological distress, life satisfaction, and self-rated physical health.

Results: Forgiveness of others (β = .20, p < .001) and self-forgiveness (β = .11, p < .01) were associated with sleep and forgiveness of others (β = .24, p < .001) and self-forgiveness (β = .27, p < .001) were associated with health. Sleep was associated with health (β = .45, p < .001) and also acted as a mediator of the associations of forgiveness of others (β = .09, p < .01) and self-forgiveness (β = .05, p < .01) with health.

Conclusions: Forgiveness of others and self-forgiveness may attenuate emotions such as anger, regret, and rumination and provide …

The Effects Of Ambient Temperature And Lighting Intensity On Wheel-Running Behavior In A Diurnal Rodent, The Nile Grass Rat (Arvicanthis Niloticus), Garrett M. Fogo, Alyssa M. Goodwin, Ohanes S. Khacherian, Brandi J. Ledbetter, Andrew J. Gall

Faculty Publications

Environmental conditions, such as the light-dark cycle and temperature, affect the display of circadian rhythmicity and locomotor activity patterns in mammals. Here, we tested the hypothesis that manipulating these environmental conditions would affect wheel-running activity patterns in a diurnal rodent, the Nile grass rat (Arvicanthis niloticus). Grass rats are diurnal in the field, however, a subset switch from a day-active pattern to a night-active pattern of activity after the introduction of a running wheel. The mechanism of this chronotype switch remains largely unknown. In the present study, grass rats were presented with running wheels in 12:12 light-dark conditions. First, subjects …

Mixed Mood State Behaviors And Circadian Dysfunction Following Homocysteic Acid Treatment: Potential Animal Model For Bipolar Disorder, Lauren Evert, Gonzalo Moya, Ryann Felton, Garrett Fogo, Nicholas Rozema, Sarah Plowman, Tymi Staub

18th Annual Celebration of Undergraduate Research and Creative Activity (2019)

Bipolar disorder is a neuropsychiatric disease characterized by cyclical fluctuations of mood states between mania and depression. Circadian rhythm abnormalities and inconsistent sleep patterns are two common symptoms of bipolar disorder (Millar, Epsie, & Scott, 2004). Elevated levels of homocysteine, in the blood or cerebrospinal fluid, commonly occurs in patients with neuropsychiatric illnesses, including bipolar disorder (Bell et al., 1992; Boushey, Beresford, Omenn, & Motulsky, 1995). Homocysteic acid (HCA), an endogenous metabolite of homocysteine, has been implicated as a harmful neurotoxin and agonist of NMDA receptors. We have previously shown that postnatal administration of HCA (from postnatal day 3-21) in …

Testing The Impact Of Prebiotics On Anxiety-Like Behaviors In Aged Male Rats, Nicholai Shaw, Marny Ehmann, Kenia Urena-Gonzalez, Anna Langholz, Peter Stewart, Jared Stygstra, Emily Zolman, Erin English, Alli Lindquist, Elizabeth Woodford

18th Annual Celebration of Undergraduate Research and Creative Activity (2019)

The composition of gut microbiota has direct impacts on neural structure, neurochemistry, and behavior. Specifically, the gut microbiota has been shown to modulate anxiety-like behaviors. In addition, administering prebiotics, compounds that promote the growth of commensal bacteria, has been demonstrated to reduce anxiety and anxiety-related behaviors. However, this effect has yet to be tested in older animals despite anxiety being implicated as a most common disorder in adult populations. Therefore, this study seeks to fill this knowledge gap by investigating the link between prebiotic interventions and anxiety-like behaviors in aged populations. It was hypothesized that older rats treated with the …

An Effective Model For Engaging Faculty And Undergraduate Students In Neuroscience Outreach With Middle Schoolers, Peter J. Vollbrecht, Riley S. Frenette, Andrew J. Gall

Faculty Publications

Engaging undergraduate students in science outreach events is critical for improving future communication between scientists and community members. Outreach events are opportunities for faculty and undergraduates to utilize active learning strategies to engage non-scientists in scientific questions and principles. Through careful design of outreach events, undergraduate students can practice science communication skills while reaching populations of the public that remain underserved and underrepresented in scientific fields. Here we describe a classroom outreach event designed to give a broad overview of the field of neuroscience to middle school students of all backgrounds by delivering the content in school, during school hours. …

Normal Behavioral Responses To Light And Darkness And The Pupillary Light Reflex Are Dependent Upon The Olivary Pretectal Nucleus In The Diurnal Nile Grass Rat, Andrew J. Gall, Ohanes S. Khacherian, Brandi Ledbetter, Sean P. Deats, Megan Luck, Laura Smale, Lily Yan, Antonio A. Nunez

Faculty Publications

The olivary pretectal nucleus (OPT) is a midbrain structure that receives reciprocal bilateral retinal projections, is involved in the pupillary light reflex, and connects reciprocally with the intergeniculate leaflet (IGL), a retinorecipient brain region that mediates behavioral responses to light pulses (i.e., masking) in diurnal Nile grass rats. Here, we lesioned the OPT and evaluated behavioral responses in grass rats to various lighting conditions, as well as their anxiety-like responses to light exposure. While control grass rats remained diurnal, grass rats with OPT lesions exhibited a more night-active pattern under 12h:12h light-dark (LD) conditions. However, when placed in constant darkness, …

The Contribution Of The Pineal Gland On Daily Rhythms And Masking In Diurnal Grass Rats, Arvicanthis Niloticus, Dorela D. Shuboni, Amna A. Agha, Thomas K. H. Groves, Andrew J. Gall

Faculty Publications

Melatonin is a hormone rhythmically secreted at night by the pineal gland in vertebrates. In diurnal mammals, melatonin is present during the inactive phase of the rest/activity cycle, and in primates it directly facilitates sleep and decreases body temperature. However, the role of the pineal gland for the promotion of sleep at night has not yet been studied in non-primate diurnal mammalian species. Here, the authors directly examined the hypothesis that the pineal gland contributes to diurnality in Nile grass rats by decreasing activity and increasing sleep at night, and that this could occur via effects on circadian mechanisms or …

Suprachiasmatic Nucleus And Subparaventricular Zone Lesions Disrupt Circadian Rhythmicity But Not Light-Induced Masking Behavior In Nile Grass Rats, Andrew J. Gall, Dorela D. Shuboni, Lily Yan, Antonio A. Nunez, Laura Smale

Faculty Publications

The ventral subparaventricular zone (vSPVZ) receives direct retinal input and influences the daily patterning of activity in rodents, making it a likely candidate for the mediation of acute behavioral responses to light (i.e., masking). We performed chemical lesions aimed at the vSPVZ of diurnal grass rats (Arvicanthis niloticus) using N-methyl-D,L-aspartic acid (NMA), a glutamate agonist. Following NMA lesions, we placed grass rats in various lighting conditions (e.g., 12:12 light-dark, constant dark, constant light); presented a series of light pulses at circadian times (CT) 6, 14, 18, and 22; and placed them in a 7-h ultradian cycle to assess behavioral masking. …

Intergeniculate Leaflet Lesions Result In Differential Activation Of Brain Regions Following The Presentation Of Photic Stimuli In Nile Grass Rats, Andrew J. Gall, Lily Yan, Laura Smale, Antonio A. Nunez

Faculty Publications

The intergeniculate leaflet (IGL) plays an important role in the entrainment of circadian rhythms and the mediation of acute behavioral responses to light (i.e., masking). Recently, we reported that IGL lesions in diurnal grass rats result in a reversal in masking responses to light as compared to controls. Here, we used Fos as a marker of neural activation to examine the mechanisms by which the IGL may influence this masking effect of light in grass rats. Specifically, we examined the patterns of Fos activation in retinorecipient areas and in brain regions that receive IGL inputs following 1-h light pulses given …

The Development Of Sleep-Wake Rhythms And The Search For Elemental Circuits In The Infant Brain, Mark S. Blumberg, Andrew J. Gall, William D. Todd

Faculty Publications

Despite the predominance of sleep in early infancy, developmental science has yet to play a major role in shaping concepts and theories about sleep and its associated ultradian and circadian rhythms. Here we argue that developmental analyses help us to elucidate the relative contributions of the brainstem and forebrain to sleep-wake control and to dissect the neural components of sleep-wake rhythms. Developmental analysis also makes it clear that sleep-wake processes in infants are the foundation for those of adults. For example, the infant brainstem alone contains a fundamental sleep-wake circuit that is sufficient to produce transitions among wakefulness, quiet sleep, …