Congratulation to all participants of the symposium for giving great presentations,
with special congratulations to the winners:
1st place: Erik Fraunberger
2nd place: Douglas Kiss
3rd place: Melissa Bexte
4th place: Scott Wong
TRANSGENERATIONAL PROGRAMMING and NEURODEVELOPMENT
Mechanisms of Transgenerational Programming by Stress: The Expression Profiles of Hippocampal Glucocorticoid Receptors
Laise Vieira, Yongxin Hao, Gerlinde Metz
Hippocampal glucocorticoid receptors (GRs) are considered to be a crucial part of the negative feedback control for terminating a stress response. Early life stress may permanently disrupt the ability of hippocampal GRs to negatively regulate the stress response axis. The present study investigated the transgenerational effects of prenatal stress on endocrine parameters by immunohistochemical and stereological analysis of GR density in hippocampal subfields of male and female F3 generation rats born to stressed great-grandmothers. Our findings show that transgenerational stress reduced GR density in dentate gyrus and CA1-2 in sex-specific patterns. These findings indicate that a family history of stress can permanently alter stress responses by downregulating GR expression even in remote generations.
Exposure to Ancestral Stress Promotes Sexually Dimorphic Behavioural Traits
Amanda Weiler, Mirela Ambeskovic, Jamshid Faraji, Gerlinde A. Metz
Prenatal stress (PS) has sexually dimorphic effects on anxiety levels in adulthood. Here we investigated if ancestral exposure to PS in previous generations will affect anxiety-like behaviour in adult rats. Anxiety-like behaviour was assessed in the adult male and female F4 rat offspring born to transgenerationally or multigenerationally stressed mothers, and controls. The results revealed that the effects of ancestral PS on anxiety-like behaviours in the elevated plus maze were limited to male offspring. Transgenerational PS exacerbated anxiety-like behaviours in comparison to multigenerationally stressed and non-stressed animals. These findings support the notion that males respond more strongly to PS than females. This behavioural trait has potential adaptive benefits. Multigenerational stress, by contrast, may promote habituation through repeated exposure.
Transgenerational Programming of Social Behaviour: Survival of the Fittest?
Adrielle P. Souza Lira, Zachary T. Erickson, Sergio M. Pellis, Gerlinde A. Metz
Prenatal and transgenerational programming by stress may prepare offspring for survival in a hostile environment by altering social behaviours. Here we investigated the impact of transgenerational stress on social behaviour, cooperation and aggression in rats. Groups of adult rats with a family history of stress and controls were tested for patterns of sharing or competing in a water competition task. Time at the water spout revealed that stress reduced enhanced competitive and aggressive behaviours. By contrast, stressed animals exposed to environmental enrichment were more willing to share access to the water spout and animals generally became more cooperative. These observations show that ancestral stress enhances dominant behaviours, which are attenuated by environmental intervention.
Preconception Paternal Alcohol Exposure Impacts Offspring Neurodevelopment
Melissa Bexte, Allonna Harker, Robbin Gibb
Though it is well known that the prenatal environment can be adversely affected by maternal experience, there is limited examination of the influence of father experience in maturation of offspring. We examined consequences of paternal alcohol exposure prior to conception on the developing brain and behavior of the offspring. A subset of paternal alcohol offspring were sacrificed on postnatal day 21 for anatomical analysis, the remaining offspring underwent behavioral testing in adulthood. These rats were sacrificed on postnatal day 160 for anatomical analysis. Anatomical findings suggest changes in cortical thickness, demonstrating possible effects of paternal alcohol exposure.
Effects of Bystander Stress on Early Behaviour and Adolescent Nicotine Sensitization
Erik Fraunberger, Bryan Kolb, Robbin Gibb
Research related to neural plasticity in the developing brain in response to stress and psychoactive drugs has provided valuable insights into how the brain works to compensate for or adapt to changing environmental pressures or stressors. The goals of this project are to investigate the effect of a novel bystander stress paradigm on offspring behavior and medial prefrontal cortex structure as well as its influence on adolescent sensitization to nicotine.
Prenatal Exposure to a ‘Double Dose’ of Valproic Acid Alters Behaviour and Neuroanatomy in a Rodent Model of Autism
Claire Niehaus, Sarah Raza, Bryan Kolb, Robbin Gibb
Autism is a heterogeneous neurodevelopmental disorder ranging from mild to severe symptomology. While current animal research has focused primarily on simulating high-functioning autism, cases of severe or low-functioning autism are less explored. The main objective of this study is to simulate low-functioning autism through the use of the valproic acid (VPA) rodent model of autism. The VPA rodent model of autism is a viable model given the behavioural and neuroanatomical correlates to autism in humans.
ADVERSITY and BRAIN FUNCTION
The effects of chronic amphetamine administration on network communication in the limbic system
Cecilia Badenhorst, Aaron Gruber
Amphetamine is a highly abused stimulant used recreationally. Evidence suggests that the repeated use of amphetamine alters network connections in various regions in the brain. The Gruber lab is currently investigating these alterations in the limbic system, which is involved in reward processing and addiction. To model this, rats were given a schedule of chronic amphetamine and EEG signals were recorded. Results of this study demonstrate that chronic amphetamine alters coherence patterns in these brain regions. By understanding the altered neural communication associated with repeated amphetamine administration, we can more fully understand the behavioral effects of amphetamine abuse.
The effect of acute amphetamine on flexible decision making
Alicia Briggs, Aaron Gruber
Previous research in both animals and humans has shown that dopamine is central to our ability to make choices that lead to good outcomes, while avoiding those that lead to adverse outcomes. Amphetamine acts to increase extracellular dopamine levels by competitive re-uptake inhibition, among other mechanisms. Currently, the Gruber lab is studying the effect of amphetamine on the reinforcement-driven response adaptation in the Matching Pennies task in rats. The sensitivity of this task to behavioral flexibility allows the results to be applicable to addiction, ADHD, and other impulse control disorders as well as dopamine disorders such as Parkinson’s disease.
Behavioral and EEG analyses of Long Term Recordings of Rats with Epileptic Seizures
Sisay Yimenu, Adam Neumann, Robrecht Raedt, Bruce McNaughton, Artur Luczak
Behavioural and Electroencephalogram (EEG) analyses of rodent models of epilepsy have been studied extensively and found to be crucial for determining the behaviours that could give valuable insight into predicting the oncoming seizure. Although a great deal of interest focuses on finding the underlying cause of epilepsy, an endeavour to predict a seizure is important in order to minimize the danger during and post seizure as well. Therefore, a considerable effort was given to classify EEG and behavioural similarities among epileptic rat models to understand the triggering factors to predict a seizure and finding possible treatment in the future.
MEMORY and FORAGING BEHAVIOUR
Mapping context-specific behaviour using immediate early genes
Kelsey O'Brien, Tine Gulbrandsen, Rob Sutherland
Previous studies have shown that the brain can store and retrieve context memories independent of the hippocampus (HPC). In the present study, we used a catDISH method to spatially and temporally map neural ensembles of behaving rats. We located a region outside of the HPC, which distinguishes between two different contexts during memory retrieval, and may be involved in non-HPC memory.
Real World Morris Task Performance in Adult Men and Women
McKinley Pawlak, Mashal Fida, Iasmim Montechiare, Erin Zelinski, Rob Sutherland
The Morris Water Task (MWT) is used to assess spatial abilities, though it has mostly been used in rodents or as a virtual or tabletop task in humans. We adapted the MWT for human subjects in the real world. Participants locomoted through a grassy field until given an auditory cue signaling that they had reached a single random, visually unmarked target location. Number of trials to criterion, trial duration, and recall of target location were analyzed in young men and women (ages 19-25). Our results indicate that humans and rats use similar strategies to solve Morris water-like tasks.
Wild hummingbirds (Selasphorus rufus) use featural information rather than geometrical cues when foraging for food in both vertical and horizontal planes
Becky Friesen, T. Andrew Hurly
Within a laboratory setting, many species have demonstrated use of geometrical information in spatial orientation when foraging for food, however subjects have rarely been tested in the wild. Fourteen wild rufous hummingbirds were trained to use a featural cue to locate a rewarded flower in a rectangular array of four artificial flowers, then tested when the cue was removed. Each bird was trained and tested in horizontal and vertical orientations. Birds chose all four flowers equally in both orientations, suggesting that they did not encode the geometry of the array but relied on featural information to locate the reward.
The Influence of Social Threat on Foraging Behaviour
Erica Nordin, David Euston
Rodent foraging behaviours can be manipulated by changing environmental features. The purpose of this experiment was to determine whether the threat of food theft by a larger adult male conspecific influenced a rat’s decision to carry food pellets back to a shelter. The foraging behaviour of rats was observed in two conditions: with a conspecific present and absent. Preliminary results of the pilot indicate a mild increase in carrying when the conspecific is present; however, this result is insignificant. A more thorough understanding of rodent foraging behaviour is important to establish consistency in experiments which use food as a motivator.
MOTOR CONTROL and REACHING
Hand Maps and Graspable Capabilities
Giovanna Zaninelli, Lara Coelho, Claudia Gonzalez
The perception of our hands is known to be greatly distorted with an overestimation of its size. If hand perception is inaccurate, how is it possible to produce precise reach-to-grasp movements? Is the perception of our hands influenced by external, ecologically-relevant stimuli? To investigate this last question we presented a big (apple) and a small (grape) graspable object near the hand while participants reported perceived hand size. Results showed that object size influenced hand perception but only for the right hand. Results are discussed in relation to relevant literature on the effects of perception on action and hemispheric differences for reach-to-grasp actions.
Everybody Loves Trains: A New Assessment of Motor Deficits in Rats
Brian Ficiur, Jamshid Faraji, Gerlinde Metz
Skilled walking provides a sensitive measure of motor function in animal models of nervous system disease. Here we developed the new Parallel Beam Task to assess limb coordination and placement accuracy of fore- and hind limbs. Rats were trained to walk across an elevated track of two parallel metal rails. Four aspects of skilled walking were scored for each limb using video analysis. Scoring multiple limb placement components enhances the sensitivity of the PBT to identify subtle deficits in skilled walking patterns. Findings from lesion studies suggest that the PBT may be useful for assessing loss and recovery of function in pre-clinical animal models of nervous system damage.
NEW METHODS AND TECHNOLOGIES
Metabonomics of Stress
Douglas Kiss, Tony Montina, Gerlinde Metz
Physiological changes within an organism alter metabolic activity. The field of qualitatively analysing these changes is called metabonomics. It has previously been shown that stress alters behavior and that these alterations can be progressively transmitted across generations to offspring. Using a trans-generational stress model we implemented 1H NMR spectroscopy of urine to analyse the metabolic change that accompanies stress.
Characterising the Expression and Distribution of Myelin Transcription Factor 1-like (MYT1L) in the Brain of the Laboratory Rat
Janet Poplawski, Youli Yao, Igor Kovalchuk, Gerlinde A. Metz
Myelin transcription factor 1-like (MYT1L), a gene belonging to the myelin transcription factor 1 gene family, has been implicated in a variety of diseases and health conditions. However, the expression and distribution of MYT1L in the normal, healthy brain has yet to be examined. Here, we explored these properties of MYT1L to further clarify its function in the nervous system. Our results indicated that, although MYT1L was expressed in nearly all brain regions, its distribution was highly heterogeneous. The findings support the proposed functions of MYT1L and also suggest novel roles of this gene in the nervous system.
Development of a Model of Multiple Carotid Micro-Emboli Injections
Richard Kline, Sunny Wang & Majid Mohajerani
Previous research has suggested that micro-infracts caused by micro-emboli, or ‘silent strokes’, may be linked to cognitive decline. These micro-infracts vary in size, and can occur at multiple times in humans. Nevertheless, past research has been focused on looking at single injections of micro-emboli, with single sizes of micro-emboli per specimen. Here, we test a model of multiple carotid injections using 15 and 20 µm fluorescent micro-emboli targeted to embed within the penetrating arterioles of the brain. Brain tissue was then analyzed for vessel blockage, micro-infracts, and hypoxia using fluorescent Dextran, TTC, H&E, and Pimonidazole.
Real Time EEG
Joshua Pepneck, Matthew Tata
EEG is a common method for understanding the brains electrical activity in response to an event. It is however quite limited in it’s portability and real time applications. We have been working towards using a portable EEG recorder to analyze raw EEG data while it is being acquired to enable for real time classification of an event, as well as the ability to then recognize that event during post training.
A Novel Method for the Semi-Automated Quantification of Dendritic Spines
Scott Wong, Aaron Gruber
Research has demonstrated that dendritic spines are dynamic structures exhibiting plastic changes in response to various stimuli. These alterations have been implicated in cellular processes such as memory, learning, and addiction. Of particular interest in the Gruber lab are the changes manifesting in the neurons of the limbic system as a result of repeated drug administration. This presentation will showcase a new method being developed to analyze altered spine morphology in this network of brain regions as a result of optogenetic stimulation or amphetamine administration.
The effects of transcranial direct current stimulation on sleep in rats
Eric Paxman, Henrique Ellwanger, LeAnna Kalvi, Karim Ali, Michael Eckert, Masami Tatsuno
Studies in humans and rodents have shown that transcranial direct current stimulation during sleep (sleep-tDCS) can alter endogenous brain oscillations and enhance memory retention. However, the effect of sleep-tDCS has not yet been investigated systematically. In this pilot study, tDCS was administered to rats during SWS or REM sleep. Preliminary analyses suggest that although many aspects of sleep are robust, it is possible to alter certain sleep features, depending on the sleep state in which tDCS is administered. We have also investigated timing relationship between hippocampal sharp waves-ripples and cortical K-complexes. We found that tDCS did not affect their timing.