Maryland Psychiatric Research Center, Administration Building, Room 2-20, Grounds of Spring Grove Hospital Center, Maple and Locust Streets, Catonsville, MD 21228
Education and Training
1990 – 1994 BA, Psychology (Cognitive Science), Yale University, New Haven, CT
1994 – 1995 MA, Psychology (Cognitive Neuroscience), University of California,
Los Angeles, CA
1995 – 1999 PhD, Psychology (Cognitive Neuroscience), University of California,
Los Angeles, CA
Post Graduate Education and Training
1999 – 2004 Postdoctoral Fellow, Neurophysiology Department,
Max Planck Institute for Brain Research, Frankfurt a.M., Germany
2000 Course in experimental animal basics and animal experimental methods
Academy for Supplementary Education at the Universities of
Heidelberg and Mannheim, Germany
2004 – 2006 Postdoctoral Fellow, Maryland Psychiatric Research Center (MPRC),
Department of Psychiatry, University of Maryland School of
Medicine (UMSOM), Baltimore, Maryland, USA
2007 UMSOM Graduate Program in the Life Sciences (GPLS),
Course in Neuropharmacology: Basic to Clinical Approaches (GPLS 604)
I received my PhD in Experimental Psychology (Cognitive Neuroscience) from UCLA in 1999, where my focus was on the consequences of prefrontal cortical dysfunction for learning and memory. Following my PhD, obtained a postdoctoral fellowship to investigate the neurophysiology of memory in humans and nonhuman primates, under Wolf Singer, at the Max Planck Institute for Brain Research, in Frankfurt, Germany, where I used EEG (in human subjects) and extracellular recording with multiple microelectrodes (in macaques) to examine the neural substrates of memory encoding, retention, and retrieval.
I moved to the Maryland Psychiatric Research Center (MPRC), at the University of Maryland School of Medicine (UMSOM), in 2004 to investigate the contribution of the brain's reward systems to impairments in learning in schizophrenia with James M Gold.
I subsequently received a K12 Multidisciplinary Clinical Research Career Development Award from the University of Maryland and the NIH, transitioning to faculty position in the Department of Psychiatry. The studies I have done at the MPRC involve the use of behavioral paradigms from the experimental literature, computational modeling techniques, and functional MRI. The purpose of these studies has been to develop a better understanding of which aspects of reward processing are impaired in schizophrenia, and which might be preserved.
My current work is designed to investigate relationships between neural correlates of learning and decision variables and the symptoms of schizophrenia.
schizophrenia, reinforcement learning, avolition, anhedonia, psychosis, dopamine
- Waltz, J.A., Xu, Z., Brown, E.C., Ruiz, R.R., Frank, M.J., and Gold, J.M. (In Press). Motivational Deficits in Schizophrenia Are Associated With Reduced Differentiation Between Gain and Loss-Avoidance Feedback in the Striatum. Biological Psychiatry: Cognitive Neuroscience and Neuroimaging. Epub 2017 Aug 11.
- Waltz, J.A. (2017). The neural underpinnings of cognitive flexibility and their disruption in psychotic illness. Neuroscience, 345, 203-217. Epub 2016 Jun 7. PMID: 27282085.
- Chang, W.C.*, Waltz, J.A.*, Gold, J.M., Chan, T.C., Chen, E.Y. (2016). Mild reinforcement learning deficits in patients with first-episode psychosis. Schizophrenia Bulletin, 42, 1476-1485. Epub 2016 May 13. PMID: 27179125.
- Waltz, J.A., Demro, C., Schiffman, J., Thompson, E., Kline, E., Reeves, G., Xu, Z., Gold, J.M. (2015). Reinforcement learning performance and risk for psychosis in youth. Journal of Nervous and Mental Disease, 203, 919-926. PMID: 26588080.
- Waltz, J.A., and Gold, J.M. (2015). Motivational Deficits in Schizophrenia and the Representation of Expected Value. In E.H. Simpson and P.D. Balsam (Eds.). Current Topics in Behavioral Neuroscience. Berlin: Springer Verlag.
- Waltz, J.A., Brown, J.K., Gold, J.M., Ross, T.J., Salmeron, B.J., Stein, E.A. (2015). Probing the dynamic updating of value in schizophrenia using a Sensory-specific Satiety Paradigm. Schizophrenia Bulletin. Epub 2015 April 1. PMID: 25834028.
- Waltz, J.A., Kasanova, Z., Ross, T.J., Salmeron, B.J., McMahon, R.P., Gold, J.M., Stein, E.A. (2013). The roles of reward, default, and executive control networks in set-shifting impairments in schizophrenia. PLoS-ONE, 8, e57257. Epub 2013 Feb 27. PMID: 23468948. PMCID: PMC3584128.
- Simpson, E.H., Waltz, J.A., Kellendonk, C., Balsam, P.D. (2012). Schizophrenia in Translation: Dissecting Motivation in Schizophrenia and Rodents. Schizophrenia Bulletin, 38, 1111-1117. Epub 2012 Sep 26. PMID: 23015686.
- Waltz, J.A., Frank, M.J., Wiecki, T.V., Gold, J.M. (2011). Altered probabilistic learning and response biases in schizophrenia: Behavioral evidence and neurocomputational modeling. Neuropsychology, 25, 86-97. PMID: 21090899.
- Waltz, J.A., Schweitzer, J.B., Ross, T.J., Kurup, P.K., Salmeron, B.J., Rose, E.J., Gold, J.M., Stein, E.A. (2010). Abnormal responses to monetary outcomes in cortex, but not in the basal ganglia, in schizophrenia. Neuropsychopharmacology, 35, 2427-39. Epub 2010 Aug 18. PMID: 20720534; PMCID: PMC2955756.
- Gold, J.M., Hahn, B., Strauss, G.P., Waltz, J.A. (2009). Turning it upside down: areas of preserved cognitive function in schizophrenia. Neuropsychology Review, 19, 294-311.
- Waltz, J.A., Schweitzer, J.B., Gold, J.M., Kurup, P.K., Ross, T.J., Salmeron, B.J., Rose, E.J., McClure, S.M., Stein, E.A. (2009). Patients with Schizophrenia have a Reduced Neural Response to Both Unpredictable and Predictable Primary Reinforcers. Neuropsychopharmacology, 34, 1567-77.
- Haenschel, C., Bittner, R., Waltz, J.A., Haertling, F., Wibral, M., Singer, W., Linden, D.E.J., and Rodriguez, E. (2009). Cortical oscillatory activity is critical for working memory as revealed by deficits in early onset schizophrenia. Journal of Neuroscience, 29, 9481-89.
- Pipa, G., Städtler, E.S., Rodriguez, E.F., Waltz, J.A., Muckli, L.F., Singer, W., Goebel, R., Munk, M.H. (2009). Performance- and stimulus-dependent oscillations in monkey prefrontal cortex during short-term memory. Frontiers in Integrative Neuroscience, 3, 25. Epub 2009 Oct.
- Waltz, J.A., Frank, M.J., Robinson, B.M., and Gold, J.M. (2007). Selective reinforcement learning deficits in schizophrenia support predictions from computational models of striato-cortical dysfunction. Biological Psychiatry 62, 756-764.
- Waltz, J.A., and Gold, J.M. (2007). Probabilistic reversal learning impairments in schizophrenia: further evidence of orbitofrontal dysfunction. Schizophrenia Research 93, 296-303.
My major current scientific interest is in understanding how abnormalities in learning and decision making relate to the symptoms of psychotic illness. My work makes use of findings and techniques from the basic cognitive neuroscience literature, including computational modeling and functional neuroimaging techniques, in conjunction with experimental reinforcement learning paradigms. We have observed an inverse relationship between clinical ratings of motivational deficits in SZ and experimental variables capturing the ability to precisely represent value and flexibly update these representations in the brain. This set of findings helps us to potentially arrive at better mechanistic understandings of both the positive and negative symptoms of SZ.
The work described above was motivated by findings from a related line of work, examining neural responses to experienced rewards, as well as the signaling of mismatches between expected and obtained outcomes, called “Reward Prediction Errors (RPEs)”, in psychiatric illness. Based on the established role for brain dopamine systems in both psychosis and RPE signaling, my colleagues and I tested the idea that RPE-signaling in schizophrenia would be disrupted, perhaps in a manner relating to symptom severity. The work below produced several unexpected findings: 1) schizophrenia patients showed relatively intact brain responses to negative outcomes, and appropriately signaled when outcomes were worse than expected (negative RPEs); 2) schizophrenia patients showed relatively disrupted brain responses to positive outcomes, and attenuated brain signals when outcomes were better than expected (positive RPEs; a similar observation was made in cocaine-dependent subjects); 3) in cross-sectional studies, schizophrenia patients gave pleasant stimuli hedonic ratings in line with those given by controls, though they failed to normatively modulate ratings of pleasant food stimuli within a session, as a consequence of sensory-specific satiety. These findings argue that motivational deficits in schizophrenia are less likely to be a consequence of sensitivity to outcomes, and more likely to result from a reduced ability to use prediction errors signals to adjust value representations.
Another related line of work, in which I have engaged, has examined the potential role of aberrant effort-cost estimation in cost/benefit decision making in schizophrenia. In the context of cost/benefit decision making, an individual may decline to carry out an action, either because the prospective reward of the action is judged to be insufficient, or because the prospective cost of the action is judged to be too high, in terms of effort. Recent work in basic neuroscience has shown that effort-cost estimation relies on fronto-striatal circuits and their modulation by dopamine systems. Given evidence of fronto-striatal dysfunction in SZ, especially with regard to motivational deficits, my colleagues and I hypothesized that motivational deficits in schizophrenia would relate to estimates of effort-cost. In the case of a task dependent on the estimation of physical effort-cost, we observed this to be true. In the case of a task dependent on the estimation of mental effort-cost, however, we observed that patients did not avoid high-effort conditions, because they had greater difficulty in detecting differences in cognitive effort demands.
Honors and Awards
1994 – 1995 University Fellowship, University of California
1996 – 1997 Ursula Mandel Fellowship, University of California
1998 – 1999 National Research Service Award, National Institutes of Health
1998 – 1999 Predoctoral Fellowship, John Douglas French Foundation for
1999 Joseph A. Gingerelli Award for the Distinguished Dissertation,
Psychology Dept, UCLA
1999 Postdoctoral Fellowship, Alexander von Humboldt Foundation
1999 – 2000 Postdoctoral Fellowship, John Douglas French Foundation for
1999 – 2003 Postdoctoral Fellowship, McDonnell-Pew Program in Cognitive
2003 – 2004 Postdoctoral Fellowship, Max Planck Institute for Brain Research
2004 – 2006 Postdoctoral Fellowship, UMSOM/MPRC
2009 H. McKee Jarboe Award for Outstanding Research in Psychiatry, UMSOM
2013 Young Investigator Mentor, International Congress on Schizophrenia
1995 – present Society for Neuroscience
1995 – present Cognitive Neuroscience Society
2008 American Psychological Society
2015 – present American College of Neuropsychopharmacology (Associate Member)
Lab website: http://www.waltzlab.org