Professor, Clinical and Neuroscience Programs *Note: Dr. Strauss will not be reviewing applications for graduate students applying during the fall 2024 cycle/fall 2025 start date* Lab Website: Clinical Affective Neuroscience Laboratory (CAN Lab): https://ugacanlab.com About: Dr. Strauss is the Franklin Professor of Psychology. The Franklin Professorship is an honor bestowed by the Dean of the UGA Franklin College of Arts and Sciences. Dr. Strauss directs the UGA Clinical Affective Neuroscience Laboratory and Georgia Psychiatric Risk Evaluation Program (G-PREP). Research Research Interests: Dr. Strauss’ program of research examines the phenomenology, etiology, assessment, and treatment of negative symptoms in schizophrenia and youth at clinical high-risk for psychosis. Negative symptoms are reductions in motivation, emotion, and behavior that are associated with a range of poor clinical outcomes. Unfortunately, interventions have proven ineffective at remediating negative symptoms. The identification of novel neurophysiological and psychological mechanisms that can serve as treatment targets for pharmacological and psychosocial treatments is therefore a significant need in our field, as is the development of new assessments that can measure the construct adequately. Research in the CAN Lab aims to address these needs in the field. Phenomenology: Our research on phenomenology has focused on determining: 1) whether negative symptoms are best conceptualized as a categorical, dimensional, or hybrid construct; 2) how many domains are part of the negative symptom construct. Our findings indicate that negative symptoms are a hybrid dimensional-categorical construct, such that people with schizophrenia differ in kind above a certain symptom threshold of negative symptoms. Beyond this threshold, negative symptom severity is predictive of individual differences in external correlates, such as cognitive impairment and functional outcome. However, negative symptoms are not unidimensional, as suggested by early factor analytic studies. Rather, negative symptoms are multi-dimensional and these dimensions have distinct pathophysiological and psychological mechanisms. Early work that we and others conducted on the factor structure of negative symptoms supported a two dimensional conceptualization, with dimensions reflecting diminished expression (EXP) and motivation and pleasure (MAP). However, using more advanced mathematical approaches, we have recently found that the construct is best considered in relation to 5 distinct domains (anhedonia, avolition, asociality, blunted affect, alogia). This 5 domain structure has been found across the 3 most contemporary measures (BNSS, CAINS, SANS), across multiple cultures and languages (e.g., English, Italian, Spanish, Chinese, Korean, Japanese), using multiple mathematical techniques (e.g., CFA, network analysis), and across chronic and clinical high-risk phases of illness. Recently, we have been examining whether these 5 domains have distinct pathophysiological mechanisms and clinical correlates to determine whether a change is needed for DSM-5 negative symptom diagnostic criteria and whether the 5 domains reflect distinct treatment targets. Etiology: The primary focus of our research is on identifying mechanisms underlying negative symptoms. Our initial studies examined the most straightforward explanation for avolitional symptoms in schizophrenia- that patients fail to engage in activities because they do not find them rewarding; however, this hypothesis was not supported because subjective and neurophysiological response to rewarding stimuli is intact in schizophrenia. This finding lead us to explore why apparently normal hedonic responses do not translate into goal-directed behavior in schizophrenia. We have demonstrated that abnormalities in several aspects of reward processing (e.g., reinforcement learning, effort-cost computation, value representation, uncertainty-driven exploration) that are driven by aberrant cortico-striatal interactions may prevent intact hedonic responses from influencing decision-making processes that are needed to initiate motivated behavior. We have also demonstrated that avolition is associated with dysfunctional cognition-emotion interactions (e.g., memory, attention), emotion regulation abnormalities, social cognition impairments, a reduction in the positivity offset, and anhedonic beliefs. In recent years, we have expanded our work on the etiology of negative symptoms into the psychosis prodrome, where we have found that reward processing deficits predict the severity of negative symptoms in at-risk youth. However, due to the greater propensity for depression in this phase of illness, hedonic deficits play a greater role in negative symptoms in the prodrome than in schizophrenia, propagating forward and creating deficits in other aspects of reward processing that also occur in schizophrenia. We are currently conducting longitudinal studies to determine which reward processing mechanisms associated with negative symptoms predict the emergence of psychotic disorders versus other conditions (e.g., depression) in youth at clinical high-risk for psychosis. Most recently, we are evaluating environmental contributions to negative symptoms in relation to a bioecosystem theoretical framework (see Strauss, 2021: https://www.frontiersin.org/articles/10.3389/fpsyt.2021.655471/full). Assessment: The development of next-generation negative symptom assessments has been another key focus of research in the CAN Lab. In 2005, NIMH held a consensus development conference on negative symptoms. A key conclusion of this meeting was that new rating scales were needed to increase chances of observing treatment effects. Two scales resulted from this initiative. Dr. Strauss was co-developer of one of these scales along with Brian Kirkpatrick, the Brief Negative Symptom Scale (BNSS), and served as PI on multiple studies validating the scale. Our lab has also led efforts in translating the BNSS into other languages and facilitating its primary intended use as an outcome measure in industry sponsored clinical trials. Most recently, Dr. Strauss and Dr. Vijay Mittal co-developed and validated a new scale for those at clinical high-risk for psychosis, the Negative Symptom Inventory-Psychosis Risk (NSI-PR). The measure is being modified and validated in a multi-site R01. Our lab has also begun developing and validating new digital phenotyping measures. This includes active (e.g., EMA surveys, videos, tasks) and passive (e.g., geolocation, accelerometry, ambient sound) negative symptom measurements taken from smart phones and smartbands (ambulatory psychophysiology, accelerometry). We are also exploring whether these tools hold promise as novel risk prediction and monitoring assessments for predicting conversion to a psychotic disorder among clinical high-risk youth. Treatment: In collaboration with colleagues at multiple institutions, we have conducted clinical trials examining the efficacy of pharmacological treatments for negative symptoms. Based on our studies showing a role for endogenous oxytocin in social cognition deficits and negative symptoms, we examined the efficacy of oxytocin as a treatment for asociality. In multiple clinical trials, oxytocin was not more effective than placebo, and we recently extended this work by demonstrating that combining oxytocin with psychosocial treatment had no added benefit over psychosocial treatment alone. We have partnered with pharmaceutical companies to investigate the efficacy of pharmacological agents for negative symptoms, testing differential efficacy for negative symptom domains. Using a network analytic approach, we recently found that avolition may be the most central symptom to target to produce global improvements in the entire negative symptom construct. Currently, we are exploring the efficacy of a novel app-based cognitive training intervention for improving emotion regulation abnormalities in an R33 grant from NIMH. We are examining whether increased prefrontal activation leads to better emotion regulation, and whether this translates into reductions in negative symptoms, positive symptoms, and improved functional outcome. Research Methods: Primary/Used for Several years: Electroencephalography (EEG), eye tracking, pupillometry, digital phenotyping/ecological momentary assessment Secondary/Newer: Functional Magnetic Resonance Imaging (fMRI), peripheral psychophysiology (electrodermal activity, electrocardiography), blood and saliva draws for biomarkers (e.g., cytokines, cortisol, oxytocin), computational modeling Lab Website: Clinical Affective Neuroscience Laboratory (CAN Lab): https://ugacanlab.com Grants: ACTIVE 4. U01MH124639 (PI: SW Woods) 09/08/2020-06/30/2025 NIMH $1,732,983; Total funding across all sites: $52,000,000 ProNET: Psychosis Risk Outcomes Network This multinational study evaluates biomarkers and clinical factors giving rise to the development of psychotic disorders in those at clinical high-risk for psychosis Role: Site PI 3. R01-MH120092 (PI: GP Strauss) 04/01/2020-03/31/2025 NIMH $2,080,177 4/5 CAPER: Computerized Assessment of Psychosis Risk This grant develops and validates a novel computerized screening battery for the early identification of psychosis among youth with prodromal syndromes. Role: PI 2. R33-MH121560 (PI GP Strauss) 07/01/2024 – 06/30/2027 NIMH $2,997,345 Cognitive training for emotion regulation in psychotic disorders. This grant examines the efficacy of a novel app-based cognitive training program for enhancing the proximal target of emotion regulation via a direct mechanistic effect on increasing prefrontal activation, as well as a distal target of improving symptoms and functional outcome. Role: PI 1. R01-MH116039 (PI GP Strauss) 03/01/2019-11/30/2025 NIMH $2,969,883 Prodromal Inventory for Negative Symptoms (PINS): A Development and Validation Study This grant develops and validates novel methods for assessing negative symptoms in youth at clinical high-risk for psychosis to enhance risk prediction algorithms Role: PI RECENTLY COMPLETED 8. R61-MH121560 (PI GP Strauss) NIMH $2,997,345 Cognitive training for emotion regulation in psychotic disorders. This grant examines the efficacy of a novel app-based cognitive training program for enhancing the proximal target of emotion regulation via a direct mechanistic effect on increasing prefrontal activation, as well as a distal target of improving symptoms and functional outcome. Role: PI 7. R21 –MH122863 (PI: GP Strauss) 04/01/2020-03/31/2023 NIMH $440,650 Computationally modeling the failure of effort to become a secondary reinforcer in schizophrenia This grant uses computational modeling and pupillometry to test the novel hypothesis that avolition in schizophrenia results from a failure of effort to become a secondary reinforcer Role: PI 6. R21-MH119438 (PI GP Strauss) 09/01/2019-06/30/2023 NIMH $415,250 Mechanisms Underlying Emotion Regulation Abnormalities in Youth at Clinical High-Risk for Psychosis This grant examines mechanisms underlying emotion regulation abnormalities at the identification, selection, and implementation stages in youth at clinical high-risk for psychosis using EMA, ambulatory psychophysiology, EEG, pupillometry, and eye-tracking. Role: PI 5. F31-MH125563 (PI: L.A. Bartolomeo) 05/24/2021-07/31/2023 NIMH $80,476 The neural basis of the positivity offset as a mechanism for avolition in schizophrenia This NRSA pre-doctoral mentored fellowship focuses on using fMRI to identify the neural mechanisms underlying avolition as a reduction in the positivity offset. Role: Mentor 4. (PI: Luther, L.) 09/01/2021-11/1/2023 American Psychological Foundation $19,726 Neural predictors and changes in relation to an mHealth intervention in psychosis. This study evaluates the efficacy of a novel mobile health intervention for negative symptoms by determining whether alterations in reward circuitry as measured via fMRI act as a mechanism of action. Role: Mentor 3. R01MH116039-02S1 (PI: Ivan Ruiz) 12/01/2019-11/30-2021 NIMH $116,282 Prodromal Inventory for Negative Symptoms (PINS): A Development and Validation Study This diversity supplement awards a fellowship for Strauss lab graduate student Ivan Ruiz to conduct a sub-study on cognitive effort mechanisms of avolition in youth with prodromal syndromes and obtain additional clinical and neuroscience based training. Role: Mentor 2. NARSAD Young Investigator Grant (PI GP Strauss) 01/15/2019-01/15/2021 Brain & Behavior Research Foundation $70,000 Neurocomputational models of psychosis risk This grant uses computational modeling approaches to examine mechanisms underlying positive and negative symptoms involved with conversion to a psychotic disorder in youth at clinical high-risk for psychosis. Role: PI 1. R21- MH112925 (PI GP Strauss) 04/01/2017- 03/31/2020 NIMH $417,456 Modeling anhedonia in schizophrenia: A stochastic dynamical systems approach This grant applies mathematical models to ecological momentary assessment data to test novel theories about anhedonia reflecting abnormalities in the temporal dynamics of emotion in schizophrenia. Role: PI Selected Publications Selected Publications: * = Student/Trainee Publication 2025/In Press 1. Whearty*, K.M., Ruiz*, I., Knippenberg*, AR., Strauss, G.P. (in press). Anhedonia reflects an encoding deficit for pleasant stimuli in schizophrenia: Evidence from the emotion-induced memory trade-off eye tracking paradigm. Neuropsychology. 2. Strauss, G.P., Knippenberg*, A.R., Allen, D.N. (in press). Anhedonia is associated with impaired memory for positive emotional stimuli in schizophrenia. Neuropsychology. 3. Luther*, L., Ahmed, A.O., Grant, P.M., Granholm, E., Gold, J.M., Williams, T.F., Pratt, D., Holden, J., Walker, E.F., Arnold*, L., Ellman, L.M., Mittal, V.A., Zinbarg, R., Silverstein, S.M., Corlett, P.R., Powers, A.R., Woods, S.W., Waltz, J.A., Schiffman, J., & Strauss, G.P. (in press). Revisiting the Defeatist Performance Belief Scale in Adults with Schizophrenia and Youth at Clinical-High Risk for Psychosis: A Comprehensive Psychometric Analysis. Schizophrenia Bulletin. 4. Luther, L., Raugh, I.M., & Strauss, G.P. (in press). Probabilistic Reinforcement Learning Impairments Predict Negative Symptom Severity and Risk for Conversion in Youth at Clinical High-Risk for Psychosis. Psychological Medicine. 5. Ibonie, S. G., Young, G., Ploe, M. L., Mauss, I. B., Alloy, L., Bavel, J. V., Borelli, J. L., Bullock, B., Holley, S. R., Jopling, E., Kamble, S., LeMoult, J., Mason, L., Moriarty, D., Nusslock, R., Okuma, A., Rutledge, R. B., Strauss, G.P, Villanueva, C. M., & Gruber, J. (in press). Associations Between Bipolar Risk with Social Networks Dimensions in Emerging Adults: two social sides of bipolar disorder. Journal of Clinical and Social Psychology. 6. Spilka*, M. J., Millman, Z. B., Waltz, J. A., Walker, E. F., Levin*, J. A., Powers, A. R., Corlett, P. R., Schiffman, J., Gold, J. M., Silverstein, S. M., Ellman, L. M., Mittal, V. A., Woods, S. W., Zinbarg, R., & Strauss, G. P. (in press). A generalized reward processing deficit pathway to negative symptoms across diagnostic boundaries. Psychological Medicine. 7. Raugh*, I.M., Strauss, G.P. (In press). Deconstructing emotion regulation in schizophrenia: The nature and consequences of positive emotion up-regulation abnormalities. Journal of Emotion and Psychopathology. 8. Strauss, G.P., Raugh*, I.M., Visser*, K.F., Walker, E.F., Mittal, V.A. (In press). Deconstructing the nature of emotion regulation impairments at the identification, selection, and implementation stages in individuals at clinical high-risk for psychosis. Psychological Medicine. 9. Raugh*, I.M., Berglund*, A.M., Strauss, G.P. (in press). Implementation of Mindfulness-Based Emotion Regulation Strategies: A Systematic Review And Meta-Analysis. Affective Science. 10. Strauss, G.P., Walker, E.F., Luther*, L., Mittal, V.A. (in press). The Negative Symptom Inventory-Psychosis Risk (NSI-PR): Psychometric Validation of the Final 11-item version. Schizophrenia Bulletin. 11. Zollicoffer*, A.N., Strauss, G.P., Luther*, L., Schiffman, J., Sims, B., Li, H. (2025). The relationship between perceived family support and subclinical positive symptoms of psychosis among Black college students. Early Intervention in Psychiatry, 19(1):e13554. 12. Weiss*, B., Dinh-Williams, L.L., Beller, N., Raugh*, I.M., Strauss, G.P., Campbell, W.K. (in press). Ayahuasca in the treatment of Post-traumatic Stress Disorder: Mixed methods case series evaluation in military combat veterans. Psychological Trauma: Theory, Research, Practice, and Policy. 13. Zhang*, L., James*, S.H., Standridge, J., Condray, R., Allen, D.N., Strauss, G.P. (in press). Social network reductions are associated with negative symptoms in schizophrenia. Social Psychiatry and Psychiatric Epidemiology. 14. Bartolomeo*, L.A., Strauss, G.P. (in press). Unpacking the anhedonia paradox across the psychosis continuum: The role of the positivity offset. Journal of Emotion and Psychopathology. 15. Mathalon et al. (in press). The Electroencephalography Protocol for the AMP SCZ Consortium: Reliability and Stability of Measures. Schizophrenia. 16. Wigman et al. (in press). Digital Health Technologies in The Accelerating Medicines Partnership® Schizophrenia Program. Schizophrenia. 17. Addington et al. (in press). Sample Ascertainment and Clinical Outcome Measures in the AMP SCZ Study. Schizophrenia. 18. Kuhney*, F.S, Strauss, G.P., Walker, E.F., James*, S.H., Mittal, V.A. (in press). Digital Phenotyping Measurements of Smartphone Social Behavior Predict Illness Progression Risk Scores in Young People at Clinical High-Risk for Psychosis. Schizophrenia Bulletin. 19. Pokorny, V., Tran, T., Williams, T. F., Kenney, J., Silverstein, S. M., Gold, J. M., Waltz, J. A., Schiffman, J., Ellman, L. M., Strauss, G. P., Walker, E. F., Woods, S. W., Powers, A. R., Corlett, P. R., & Mittal, V. A. (in press). Functional Correlates of Atypical Visuoperceptual Organization in a Multisite Clinical High Risk Sample. Journal of Psychopathology and Clinical Science. 20. Luther*, L., Zhang*, Z., James*, S.H., Zhang*, L., Standridge, J., Arnold*, L., Condray, R., Allen, D.N., & Strauss, G.P. (in press). Resource deprivation in the home environment is associated with negative symptoms in outpatients with schizophrenia. Schizophrenia. 2024 1. Knippenberg*, A.R, Yavari*, S., Strauss, G.P. (2024). Negative auditory hallucinations are associated with increased activation of the defensive motivational system in schizophrenia. Schizophrenia Research: Cognition, 39:100334. 2. James*, S.H., Ahmed, A.O., Harvey, P.D., Saoud, J.B., Davidson, M., Kuchibhatla, R., Luthringer, R., Strauss GP. (2024). Network intervention analysis indicates that roluperidone achieves its effect on negative symptoms of schizophrenia by targeting avolition. European Neuropsychopharmacology, 87, 18-23. 3. Luther*, L., Raugh*, I.M., Grant, P.M., Beck, A.T., Strauss, G.P. (2024). The Role of Defeatist Performance Beliefs in State Fluctuations of Negative Symptoms in Schizophrenia Measured in Daily Life via Ecological Momentary Assessment. Schizophrenia Bulletin, 50(6), 1427-1435. 4. Alliende, L.M.; Strauss, G.P.; Yang, L; Mittal, V.A. (2024). Perceptions of Stigma in Youth at Clinical High Risk for Psychosis and Depressive Symptomatology. Schizophrenia Research, 269:79-85. 5. Rossi-Goldthorpe R, Silverstein SM, Gold JM, Schiffman J, Waltz JA, Williams TF, Powers AR, Woods SW, Zinbarg RE, Mittal VA, Ellman LM., Strauss, G.P., Walker, E.F., Levin, J.A., Castiello, S., Kenney, J., Corlett, P.R. (2024). Different learning aberrations relate to delusion-like beliefs with different contents. Brain, 147(8):2854-2866. 6. Pratt, D. N., Treadway, M. T., Strauss, G. P., Mittal, V. A. (2024). Diminished Differentiation of Rewards in Individuals at Clinical High-Risk for Psychosis. European Archives of Psychiatry and Clinical Neuroscience, 274(6):1437-1445. 7. Wannan, C.M.J. et al. (2024). AMP SCZ: Rationale and study design of the largest global prospective cohort study of clinical high-risk for psychosis. Schizophrenia Bulletin,50, 496-512. 8. Luther*, L., Jarvis*, S.A., Spilka*, M.J., & Strauss, G.P. (2024). Global reward processing deficits predict negative symptoms transdiagnostically and transphasically in a severe mental illness-spectrum sample. European Archives of Psychiatry and Clinical Neuroscience, 274(7):1729-1740. 9. Cowan, T., Rodriguez, Z., Strauss, G.P.,Raugh*, I.M., Cohen, A.S. (2024). Computerized analysis of facial expression reveals objective indices of blunted facial affect: A short communication. European Archives of Psychiatry and Clinical Neuroscience, 274(7):1771-1775. 10. Strauss, G.P.(2024). Environmental factors contributing to negative symptoms in youth at clinical high-risk for psychosis and outpatients with schizophrenia. Social Psychiatry and Psychiatric Epidemiology, 59(7):1167-1175. 11. Raugh*, I.M., Strauss, G.P. (2024). Integrating Mindfulness Into The Extended Process Model Of Emotion Regulation: The Dual-Mode Model Of Mindful Emotion Regulation. Emotion, 24(3), 847-866. 12. Woods SW, Parker S, Kerr MJ, Walsh BC, Wijtenburg SA, Prunier N, Nunez AR, Buccilli K, Mourgues-Codern C, Brummitt K, Kinney KS, Trankler C, Szacilo J, Colton BL, Ali M, Haidar A, Billah T, Huynh K, Ahmed U, Adery LL, Marcy PJ, Allott K, Amminger P, Arango C, Broome MR, Cadenhead KS, Chen EYH, Choi J, Conus P, Cornblatt BA, Glenthøj LB, Horton LE, Kambeitz J, Kapur T, Keshavan MS, Koutsouleris N, Langbein K, Lavoie S, Diaz-Caneja CM, Mathalon DH, Mittal VA, Nordentoft M, Pasternak O, Pearlson GD, Gaspar PA, Shah JL, Smesny S, Stone WS, Strauss GP, Wang J, Corcoran CM, Perkins DO, Schiffman J, Perez J, Mamah D, Ellman LM, Powers AR 3rd, Coleman MJ, Anticevic A, Fusar-Poli P, Kane JM, Kahn RS, McGorry PD, Bearden CE, Shenton ME, Nelson B, Calkins ME, Hendricks L, Bouix S, Addington J, McGlashan TH, Yung AR (2024). Development of the PSYCHS: Positive SYmptoms and Diagnostic Criteria for the CAARMS Harmonized with the SIPS. Early Intervention in Psychiatry, 18(4):255-272. 13. James*, S.H., Strauss, G.P. (2024). Racial differences in attenuated psychotic symptoms during the COVID-19 pandemic. Early Intervention in Psychiatry, 18(2), 165-169. Other Information Of note: Philosophy of Graduate Training: I encourage my postdocs, graduate students, and employees to develop a sound theoretical knowledge base in our area of work, gain methodological expertise in the use of cognitive neuroscience methods (e.g., ERP, eye-tracking), build basic research skills (e.g., programming, writing, statistics), and develop strong clinical abilities that will facilitate their clinical research and practice (e.g., diagnostic and symptom interviewing, neuropsychology). I emphasize the importance of developing a niche area and help my trainees plan and design a series of independent studies that build upon one another, with the goal of creating their own independent program of research. I also invest time in the professional development of my trainees via regular meetings to discuss strategies for success at different stages of academic careers, and by encouraging them to attend scientific meetings where they can present research and make connections with others in the field. Graduate students and postdocs who have a strong interest in pursuing an academic career in psychosis research will be a strong fit for this lab.
