Research and Teaching Interests
My research goal is to use and advance sophisticated behavioral paradigms, coupled with neuropharmacology and neurochemical monitoring techniques, to elucidate the precise neural mechanisms and systems that underlie discrete aspects of motivated learning and decision-making. Moreover, my goals extend to understanding how disorders, such as obesity and addiction, marked by maladaptive decision-making result in such aberrant motivated behavior. Towards this goal my lab uses several approaches in parallel and often in combination:
- In vivo electrochemistry
o Fast-scan cyclic voltammetry for real time online
monitoring of dopamine
o Biosensors for near-real time neurotransmitter
measurement (glutamate, dopamine, acetylcholine)
- Instrumental Conditioning
- Pavlovian Conditioning
Wassum KM, Tolosa VM, Tseng TC, Balleine BW, Monbouquette HG, Maidment NT. (2012) Transient extracellular glutamate events in the basolateral amygdala track reward seeking actions. J. Neurosci, 32(8): 2734-2746.
Wassum KM, Ostlund SB, Maidment NT. (2012) Phasic mesolimbic dopamine signaling precedes and predicts performance of a self-initiated action sequence. Biological Psychiatry.
Wassum KM, Ostlund SB, Balleine BW, Maidment NT (2011). Differential dependence of Pavlovian incentive motivation and instrumental incentive learning processes on dopamine signaling. Learn Mem, 18(7):475-83.
Wassum KM, Cely IC, Balleine BW, Maidment NT. (2011) Mu, not delta or kappa opioid receptors in the basolateral amygdala are necessary for learning about increases, but not decreases in incentive value. J. Neurosci, 31(5): 1583-1590.
Ostlund SB, Wassum KM, Murphy NP, Balleine BW, Maidment NT. (2011) Extracellular dopamine levels in striatal subregions track shifts in motivation and response cost during instrumental conditioning. J. Neurosci, 31(1): 200-207.
Wassum KM, Cely IC, Ostlund SB, Maidment NT, Balleine BW. (2009) Disruption of endogenous opioid activity during instrumental learning enhances habit acquisition. Neuroscience, 163(3): 770-80.
Wassum KM, Ostlund SB, Maidment NT, Balleine BW. (2009) Distinct opioid circuits determine the palatability and the desirability of rewarding events. Proc Natl Acad Sci USA, 106(30): 12512-7.
Wassum KM, Tolosa VM, Wang J, Walker E, Monbouquette HG, Maidment NT. (2008) Silicon wafer-based platinum microelectrode array biosensor for near real-time measurement of glutamate in vivo. Sensors, 8: 5023-5036.
Dr. Wassum's Publications on PubMed