Steve Reilly

Our research concerns the neural mechanisms of learning, memory and motivation. More specifically, we are interested in determining the roles of central gustatory nuclei in taste-guided and taste-motivated phenomena with an emphasis on taste neophobia and conditioned taste aversions (CTAs) induced with poisons/toxins or drugs of abuse (Lin, Arthurs & Reilly, 2014; 2017). Our work suggests that forebrain nuclei are responsible for the detection of taste novelty and provide feedback to a brainstem structure (parabrachial nucleus) that governs the integration of gustatory and aversive viscerosensory information. With clinical relevance aforethought, we are particularly interested in determining whether CTA acquisition and consolidation are dependent upon protein synthesis and/or glutamate receptors in the parabrachial nucleus. We believe that understanding of the neural substrates of CTA learning will not only yield important insights into the neural integration of gustatory and visceral functions but may provide a foundation for the development of treatments and interventions that might ameliorate the unwanted, and oftentimes debilitating, nutritional side effects of invasive medical treatments such as chemo- and radiation therapy.

Our recent work has opened several new directions for research and is the basis of a more comprehensive analysis of taste learning. Specifically, we have shown that taste neophobia involves a substantial reduction in palatability of the novel taste stimulus, and that palatability increases with repeated benign exposures until that taste is recognized as familiar and safe (i.e., food becomes more pleasurable as neophobia dissipates). To be effective, the CTA mechanism must be engaged sooner rather than later. That is, the earliest onset signs of a poison must trigger the mechanism. In the context of the ingestion of a new food, the neophobic reaction not only involves a downshift in palatability (thereby restricting intake of a potentially dangerous item) but also primes the feeding system such that a negative deviation of internal well-being or the onset of a novel body state will be sufficient to activate the CTA mechanism. The price of a CTA mechanism that is triggered by early onset signs is the occurrence of false positives. This is the price of survival in the world in which the CTA mechanism evolved, a world that did not include drugs of abuse. Although their negative properties may be entirely responsible for CTAs induced with drugs of abuse, it is possible that some early onset signs of their positive properties are, mistakenly, taken as evidence of poisoning and thereby contribute to the inevitable acquisition of the CTA. Thus, taste neophobia and CTA are exquisitely developed mechanisms that defend our feeding system. Research based on this analysis is expected to benefit understanding relevant to a number of clinical conditions including, for example, obesity and the disordered neophobic response (termed ARFIDs) evident in young populations that limits inclusion of nutritious foods into the developing diet.

Books

Reilly, S. (Editor). (2018). Food Neophobia: Behavioral and Biological Influences. Elsevier.

Frieman, J., and Reilly, S. (2015). Learning: A Behavioral, Cognitive, and Evolutionary Synthesis. SAGE Publications, Inc.

Schachtman, T.R. and Reilly, S. (Editors). (2011). Associative Learning and Conditioning Theory: Human and Non-Human Applications. Oxford University Press: New York.

Reilly, S., and Schachtman, T.R. (Editors). (2009). Conditioned Taste Aversion: Behavioral and Neural Processes. Oxford University Press: New York.

Articles

Arthurs, J., Lin, J.-Y., and Reilly, S. (2018). Inhibiting gustatory thalamus or medial amygdala has opposing effects on taste neophobia. Neurobiology of Learning and Memory,156, 24-32

Lin, J.-Y., Arthurs, J., and Reilly, S. (2018). The effects of amygdala and cortical inactivation on taste neophobia. Neurobiology of Learning and Memory,155, 322-329.

Reilly, S. (2018). Taste neophobia: Neural substrates and palatability. In: S. Reilly  (Editor). Food Neophobia: Behavioral and Biological Influences (pp. 77-109). Elsevier.

Arthurs, J., Lin, J.-Y., Ocampo, R., and Reilly, S. (2017). Lactose malabsorption and taste aversion learning. Physiology and Behavior, 180, 39–44

Lin, J.-Y., Arthurs, J., and Reilly, S. (2017). Anesthesia-inducing drugs also induce conditioned taste aversions. Physiology and Behavior,177,  247-251.

Lin, J.-Y., Arthurs, J., and Reilly, S (2017). Conditioned taste aversions: From poisons to pain to drugs of abuse. Psychonomic Bulletin & Review, 24, 335-351.

Lin, J.-Y., Arthurs, J., and Reilly, S. (2015). Gustatory insular cortex, aversive taste memory and taste neophobia. Neurobiology of Learning and Memory, 119, 77-84.

Lin, J.-Y., Arthurs, J., and Reilly, S. (2014). Conditioned taste aversion, drugs of abuse and palatability. Neuroscience and Biobehavioral Reviews, 45, 28-45.

Lin, J.-Y., Arthurs, J., and Reilly, S. (2013). Reduced palatability in pain-induced conditioned taste aversions. Physiology and Behavior, 119, 79-85.

Arthurs, J. and Reilly, S. (2013). Role of the gustatory thalamus in taste learning. Behavioural Brain Research, 250, 9-17.

Lin, J.-Y., Amodeo, L.R., Arthurs, J., and Reilly, S. (2012). Anisomycin infusions in the parabrachial nucleus and taste neophobia. Neurobiology of Learning and Memory, 98, 348-353.

Lin, J.-Y., and Reilly, S. (2012). Amygdala-gustatory insular cortex connections and taste neophobia. Behavioural Brain Research, 235, 182-188.

Lin, J.-Y., Amodeo, L.R, Arthurs, J., and Reilly, S. (2012). Taste neophobia and palatability: The pleasure of drinking. Physiology and Behavior, 106, 515-519.

Lin, J.-Y., Roman, C., Arthurs, J., and Reilly, S. (2012). Taste neophobia and c-Fos expression in the rat brain. Brain Research, 1448, 82-88.

Arthurs, J., Lin, J.-Y., Amodeo, L.R, and Reilly, S. (2012). Reduced palatability in drug-induced taste aversion: II. Aversive and rewarding unconditioned stimuli. Behavioral Neuroscience, 126, 433-444.

Lin, J.-Y., Arthurs, J., Amodeo, L.R, and Reilly, S. (2012). Reduced palatability in drug-induced taste aversion: I. Variations in the initial value the conditioned stimulus. Behavioral Neuroscience, 126, 423-432.

Schachtman, T.R. and Reilly, S. (2011). Things You Always Wanted to Know about Conditioning, but Were Afraid to Ask. In: T.R. Schachtman and S. Reilly (Editors).Associative Learning and Conditioning Theory: Human and Non-Human Applications (pp. 3-23). Oxford University Press: New York.

Lin, J.-Y., Arthurs, J., and Reilly, S. (2011). Role of the insular cortex in morphine-induced conditioned taste avoidance. Brain Research, 1384, 80-88.

Neath, K., Limebeer, C.L., Reilly, S., and Parker, L.A. (2010). Increased liking for a solution is not necessary for the attenuation of neophobia in rats. Behavioral Neuroscience, 124, 398-404.

Lovaglio, J., Lin, J.-Y., Roman, C., and Reilly, S. (2010). Basolateral amygdala and morphine-induced taste avoidance in the rat. Physiology and Behavior, 99, 419-423.

Lin, J.-Y., Roman, C., and Reilly, S. (2009). Taste-potentiated odor aversion learning in rats with lesions of the insular cortex. Brain Research, 1297, 135-142.

Lin, J.-Y., Roman, C., and Reilly, S. (2009). Morphine-Induced Suppression of Conditioned Stimulus Intake: Effects of stimulus type and insular cortex lesions. Brain Research, 1292, 52-60.

Lin, J.-Y., Roman, C., and Reilly, S. (2009). Insular cortex and consummatory successive negative contrast in the rat. Behavioral Neuroscience, 123, 810-814.

Roman, C., Lin, J.-Y., and Reilly, S. (2009). Conditioned taste aversion and latent inhibition following extensive taste preexposure in rats with insular cortex lesions. Brain Research, 1259, 68-73.

Lin, J.-Y., Roman, C., St. Andre, J., and Reilly, S. (2009). Taste, olfactory and trigeminal neophobia in rats with forebrain lesions. Brain Research, 1251, 195-203.

Roman, C., and Reilly, S. (2009). Insular cortex lesions and morphine-induced suppression of CS intake in the rat. Behavioral Neuroscience, 123, 206-211.

Reilly, S. (2009). Central gustatory system lesions and conditioned taste aversion. In: S. Reilly and T.R. Schachtman (Editors). Conditioned Taste Aversion: Behavioral and Neural Processes (pp. 309-327). Oxford University Press: New York.