Behavioral Neurobiology Commons^™

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, …

Feedforward And Feedback Projections Of Caudal Belt And Parabelt Areas Of Auditory Cortex: Refining The Hierarchical Model, Troy A. Hackett, Lisa A. De La Mothe, Corrie R. Camalier, Arnaud Falchier, Peter Lakatos, Yoshinao Kajikawa, Charles E. Schroeder

Psychological Sciences and Counseling Faculty Research

Our working model of the primate auditory cortex recognizes three major regions (core, belt, parabelt), subdivided into thirteen areas. The connections between areas are topographically ordered in a manner consistent with information flow along two major anatomical axes: core-belt-parabelt and caudal-rostral. Remarkably, most of the connections supporting this model were revealed using retrograde tracing techniques. Little is known about laminar circuitry, as anterograde tracing of axon terminations has rarely been used. The purpose of the present study was to examine the laminar projections of three areas of auditory cortex, pursuant to analysis of all areas. The selected areas were: middle …

Possible Role Of Adrenergic Receptors In Epilepsy-Associated Depression, Hannah Marie Redwine

Honors Program Theses and Research Projects

Depression is one of the most frequent comorbidities of temporal lobe epilepsy. Rats subjected to pilocarpine-induced status epilepticus (SE), develop depressive impairments that may stem from the dysregulation of the hypothalamic-pituitary-adrenal (HPA) axis and/or a decrease in central serotonin neurotransmission. Based on performance in the forced swim test and increased activity of the HPA axis, Post-SE animals were classified as those with Moderate and severe depressive impairments. In both moderately and severely impaired rats, raphe-to-hippocampus serotonergic neurotransmission is decreased and the function of post-synaptic 5-HTrA receptors in the hippocampus is diminished. However, in post-SE rats with severe depressive like behavior, …

Territorial Behavior And Cortical Brain Plasticity In Adult Male Sceloporus Occidentalis, Daniel R. Pfau

Master's Theses

The hippocampus is a brain region that can undergo tremendous plasticity in adulthood. The hippocampus is related to the formation of spatial memories in birds and mammals. In birds, plasticity in the hippocampus occurs when formation of such memories is directly relevant to survival or reproduction, such as for breeding or food caching. In reptiles, the homologues to the hippocampus are the dorsal and medial cortices (DC and MC). In several lizard, snake and turtle species, these structures have been related to spatial memory. Experimental investigations indicate that differences in DC volume are related to space use associated with differing …

Investigating Habits: Strategies,Technologies And Models, Kyle S. Smith, Ann M. Graybiel

Dartmouth Scholarship

Understanding habits at a biological level requires a combination of behavioral observations and measures of ongoing neural activity. Theoretical frameworks as well as definitions of habitual behaviors emerging from classic behavioral research have been enriched by new approaches taking account of the identification of brain regions and circuits related to habitual behavior. Together, this combination of experimental and theoretical work has provided key insights into how brain circuits underlying action-learning and action-selection are organized, and how a balance between behavioral flexibility and fixity is achieved. New methods to monitor and manipulate neural activity in real time are allowing us to …

Effects Of 5-Hydroxytryptamine 2c Receptor Agonist Mk212 And 2a Receptor Antagonist Mdl100907 On Maternal Behavior In Postpartum Female Rats, Weihai Chen, Qi Zhang, Wenxin Su, Yu Yang, Jing Qiao, Nan Sui, Ming Li

Department of Psychology: Faculty Publications

Maternal behavior in rats is a highly motivated and well-organized social behavior. Given the known roles of serotonin (5-HT) in emotion, motivation, social behavior, and major depression – and its known interaction with dopamine – it is likely that serotonin also plays a crucial role in this behavior. So far, there are surprisingly few studies focusing on 5-HT in maternal behavior, except for maternal aggression. In the present study,we examined the effects of 5-HT_2C receptor agonism and 5-HT_2A receptor antagonism on maternal behavior in postpartum female rats.We hypothesized that activation of 5-HT_2C receptors and blockade of 5-HT …

Supraspinal And Spinal Mechanisms Of Morphine-Induced Hyperalgesia, Caroline A. Arout

Dissertations, Theses, and Capstone Projects

Morphine is the most prominent pharmacological treatment for moderate to severe pain in both acute and chronic paradigms. However, morphine notoriously elicits a paradoxical state of increased pain sensitivity known as hyperalgesia that complicates its use in clinical application. Research over the past three decades has reported that morphine-induced hyperalgesia is dose- and sex-dependent, and likely involves the synchronous activity of several neural networks beyond the opioid system. Whereas systemic, supraspinal, and spinal administration of morphine all cause hyperalgesia that is differentially reversible by N-methyl-D-aspartate receptor (NMDAR) antagonists or melanocortin-1 receptor (MC1R) antagonists, it is unknown as to whether or …

Quantitative Evaluation Of Microglial Activation And Vascularization In Suicide, Tatiana Pavlovna Schnieder

Dissertations, Theses, and Capstone Projects

Accumulated evidence points to immunological factors in psychiatric disorders. In a variety of chronic neurological disorders, exacerbation is associated with inflammation and a loss of integrity of the blood-brain barrier. Microglia, the principal brain immunological cells in the healthy state, respond to changes in the internal environment of the brain through a sequence of activated states. This study compared microglial phenotypes in the white matter of autopsy brains from 11 suicide victims and 25 subjects who died involuntarily. Both groups included cases with and without major psychiatric disorders, which were determined by PA interviews. Cases were matched for sex, age, …

Predictable And Predictive Emotions: Explaining Cheap Signals And Trust Re-Extension, Eric Schniter, Roman M. Sheremeta

ESI Publications

Despite normative predictions from economics and biology, unrelated strangers will often develop the trust necessary to reap gains from one-shot economic exchange opportunities. This appears to be especially true when declared intentions and emotions can be cheaply communicated. Perhaps even more puzzling to economists and biologists is the observation that anonymous and unrelated individuals, known to have breached trust, often make effective use of cheap signals, such as promises and apologies, to encourage trust re-extension. We used a pair of trust games with one-way communication and an emotion survey to investigate the role of emotions in regulating the propensity to …

A Bittersweet Investigation Of Availability And Nutritive Value As Determinants Of Volitional Sucrose Consumption, Milan D. Valyear

Theses and Dissertations (Comprehensive)

Rats given ~24 h access to a 4% sucrose solution every 3^rd day (E3DA) consume about 100 g more solution than rats with continuous, everyday access (EDA). Under the same EDA-E3DA conditions rats will consume similar amounts of a more concentrated 8 or 16% sucrose solutions (Eikelboom, Hewitt, & Adams, Unpublished). It maybe that with these more concentrated solutions rats hit a satiety limit that prevents a difference between EDA and E3DA consumption from being evident. Experiment 1 was conducted to investigate the effect of adding quinine to 4% and 8% sucrose solutions with the intention of reducing consumption …

Recovery From Acute Toluene Intoxication Is Facilitated By The Nmda Receptor Co-Agonist D-Serine, But Not The Gabaa Receptor Antagonist Picrotoxin, Susan R. Samuel-Herter

Theses and Dissertations (Comprehensive)

Toluene is a volatile solvent found in many household products and when intentionally inhaled results in intoxication. In rats, acute inhalation of toluene results in sedation and neurological impairments, with marked increases in ambulation and vertical behaviour during the recovery period. Previous in vitro research has shown that toluene may exert its effects by inhibiting NMDA receptors, and / or by activating GABA_A receptors. To test whether modulation of these receptors are also implicated in the changes in motor behaviour and neurological impairments resulting from toluene vapour inhalation, rats were injected with the NMDA receptor co-agonist D-serine (1000 mg/kg …

Aiming Attention Using Selective Stimulation Of Locus Coeruleus And Its Medial Prefrontal Efferents, Zackary A. Cope

MUSC Theses and Dissertations

Appropriate modification of behavior in response to dynamic environmental conditions is essential for the adaptation and survival of most biological organisms. This adaptability allows for organisms to maximize the benefit of behavior related energy expenditure (utility) while minimizing cost. Modern theories of locus coeruleus (LC) function implicate a pivotal role for the noradrenergic (NA) nucleus in mediating switches between focused behavior during periods of high utility (exploit) versus disengagement of behavior and exploration of other, more rewarding opportunities. Two modes of activity in LC neurons have been well characterized. During periods of accurate and focused behavior, LC neurons exhibit suppressed …

Dopaminergic And Activity-Dependent Modulation Of Mechanosensory Responses In Drosophila Melanogaster Larvae, Josh S. Titlow

Theses and Dissertations--Biology

A central theme of this dissertation is nervous system plasticity. Activity-dependent plasticity and dopaminergic modulation are two processes by which neural circuits adapt their function to developmental and environmental changes. These processes are involved in basic cognitive functions and can contribute to neurological disorder. An important goal in modern neurobiology is understanding how genotypic variation influences plasticity, and leveraging the quantitative genetics resources in model organisms is a valuable component of this endeavor. To this end I investigated activity-dependent plasticity and dopaminergic modulation in Drosophila melanogaster larvae using neurobiological and genetic approaches.

Larval mechanosensory behavior is described in Chapter 2. …

The Effects Of Chronic Simvastatin Treatment On The Expression Of Behavioral Symptoms In A Transgenic Mouse Model Of Huntington’S Disease, Ashley Whitmarsh

LSU New Orleans Theses and Dissertations

Huntington’s disease (HD) is a heritable, neurodegenerative disorder characterized by motor, cognitive, and psychiatric disturbances. An unstable CAG expansion within the gene normally encoding for the Huntingtin protein is responsible. The expanded mutant form of Huntingtin and the putative protein co-factor Rhes interact and cause cell death within the striatum. We hypothesized chronic treatment with simvastatin, a cholesterol lowering drug, would disrupt the biosynthetical pathway which gives both Rhes and its target cells binding sites and render Rhes inactive. Healthy and HD mice were treated with simvastatin or a vehicle. Animals’ motor behavior was assessed with three separate tests over …

Iptakalim Attenuates Self-Administration And Acquired Goal-Tracking Behavior Controlled By Nicotine, S. Charntikov, N. Swalve, Steven T. Pittenger, K. Fink, S. Schepers, G. C. Hadlock, A. E. Fleckenstein, G. Hu, Ming Li, Rick A. Bevins

Department of Psychology: Faculty Publications

Iptakalim is an ATP-sensitive potassium channel opener, as well as an a4b2-containing nicotinic acetylcholine receptor (nAChR) antagonist. Pretreatment with iptakalim diminishes nicotine-induced dopamine (DA) and glutamate release in the nucleus accumbens. This neuropharmacological profile suggests that iptakalim may be useful for treatment of nicotine dependence. Thus, we examined the effects of iptakalim in two preclinical models. First, the impact of iptakalim on the interoceptive stimulus effect of nicotine was evaluated by training rats in a discriminated goal-tracking task that included intermixed nicotine (0.4 mg/kg, SC) and saline sessions. Sucrose was intermittently presented in a responseindependent manner only on nicotine sessions. …

Mtorc1 Signaling In Memory Formation And Dysfunction, Natalia S. Rozas De O'Laughlin

Dissertations and Theses (Open Access)

The mechanistic Target of Rapamycin Complex 1 (mTORC1) pathway integrates cellular availability of growth factors, energy and amino acids to regulate protein synthesis and autophagy. The mTORC1 pathway has also been shown to be required for memory consolidation, and its dysregulation is associated with many neurological disorders. MTORC1 is negatively regulated by the tuberous sclerosis complex (TSC1/2). When ATP and growth factors are available, TSC1/2 is inhibited and mTORC1 activity can be restored. In a complementary regulatory pathway, amino acids signal to mTORC1 through the Rag GTPases and Ragulator complex, which modulate the translocation of mTORC1 from the cytoplasm to …

Neural Correlates Of Audiovisual Speech Perception In Aphasia And Healthy Aging, Sarah H. Baum

Dissertations and Theses (Open Access)

Understanding speech in face-to-face conversation utilizes the integration of multiple pieces of information, most importantly the auditory vocal sounds and visual lip movements. Prior studies of the neural underpinnings of audiovisual integration in the brain have provided converging evidence to suggest that neurons within the left superior temporal sulcus (STS) provide a critical neural hub for the integration of auditory and visual information in speech. While most studies of audiovisual processing focus on neural mechanisms within healthy, young adults, we currently know very little about how changes to the brain can affect audiovisual integration in speech. To examine this further, …

Day-Night Differences In Neural Activation In Histaminergic And Serotonergic Areas With Putative Projections To The Cerebrospinal Fluid In A Diurnal Brain, Alexandra Castillo-Ruiz, Andrew J. Gall, Laura Smale, Antonio A. Nunez

Faculty Publications

In nocturnal rodents, brain areas that promote wakefulness have a circadian pattern of neural activation that mirrors the sleep/wake cycle, with more neural activation during the active phase than during the rest phase. To investigate whether differences in temporal patterns of neural activity in wake-promoting regions contribute to differences in daily patterns of wakefulness between nocturnal and diurnal species, we assessed Fos expression patterns in the tuberomammillary (TMM), supramammillary (SUM), and raphe nuclei of male grass rats maintained in a 12:12 h light-dark cycle. Day-night profiles of Fos expression were observed in the ventral and dorsal TMM, in the SUM, …

Sensory-Specific Appetition: Postingestive Detection Of Glucose Rapidly Promotes Continued Consumption Of A Recently Encountered Flavor, Kevin P. Myers, Marisa S. Taddeo, Emily K. Richards

Faculty Journal Articles

It is generally thought that macronutrients stimulate intake when sensed in the mouth (e.g., sweet taste) but as food enters the GI tract its effects become inhibitory, triggering satiation processes leading to meal termination. Here we report experiments extending recent work (see [1]) showing that under some circumstances nutrients sensed in the gut produce a positive feedback effect, immediately promoting continued intake. In one experiment, rats with intragastric (IG) catheters were accustomed to consuming novel flavors in saccharin daily while receiving water infused IG (5 ml/15 min). The very first time glucose (16% w/w) was infused IG instead of water, …

Explorations Of Object And Location Memory Using Fmri, Andrew D. Passaro, L. Caitlin Elmore, Timothy M. Ellmore, Kenneth J. Leising, Andrew C. Papanicolaou, Anthony A. Wright

Publications and Research

Content-specific sub-systems of visual working memory (VWM) have been explored in many neuroimaging studies with inconsistent findings and procedures across experiments. The present study employed functional magnetic resonance imaging (fMRI) and a change detection task using a high number of trials and matched stimulus displays across object and location change (what vs. where) conditions. Furthermore, individual task periods were studied independently across conditions to identify differences corresponding to each task period. Importantly, this combination of task controls has not previously been described in the fMRI literature. Composite results revealed differential frontoparietal activation during each task period. A separation of object …