Central Monoaminergic Systems

 

The primary research focus of the Waterhouse laboratory is to understand the role of the centrall monoaminergic systems in brain function and behavior. More specifically, the lab is concerned with the anatomy and physiology of the brainstem noradrenergic and serotonergic efferent systems as they relate to executive function and the sensory-processing capabilities of an organism.

These studies employ a broad spectrum of behavioral, neuroanatomical, electro-physiological, and molecular techniques including microiontophoresis; single and multi-unit extracellular recording from anesthetized animals; simultaneous spike train recordings from multiple arrays of single neurons in waking animals; computer-based acquisition and analysis of spike train data; behavioral paradigms for signal detection, sustained and flexible attention; mapping of monoamine projections from source nuclei using retrograde tracer substances, immune-histochemistry, intersectional genetic models, and viral vector strategies; molecular phenotyping of laser captured monoaminergic neurons using qrtPCR.

The underlying theme of this work is that synaptically released norepinephrine and serotonin operate as complementary neuromodulatory substances that regulate the responsiveness of sensory neurons, sensory circuits, and sensory networks to synaptic inputs. As such, these systems may play a significant role in the ability of the organism to orient and attend to novel or salient stimuli from the sensory surround. More recent work focuses on monoaminergic regulation of prefrontal cortical circuit physiology and executive function - planning, attending, deciding.

Clinical implications of this work which have led to related experimental studies are that these monoaminergic systems may underlie some of the behavioral actions of psychostimulant drugs such as cocaine and methylphenidate (RitalinĀ®) and the cognitive deficits that accompany normal aging, anxiety/PTSD, HIV neuroAIDS, and attention disorders such as ADHD.