Patrick Skosnik, PhD

Dr. Skosnik is an Associate Professor in the Department of Psychiatry and directs the Psychophysiology Laboratory within the VA-CMHC-Yale Schizophrenia Research Clinic (Directed by Dr. Deepak C. D’Souza and Dr. Mohini Ranganathan). The long-term goals of his research program are focused on ascertaining the neurobiological bases of psychosis and substance abuse, particularly in relation to the human cannabinoid system. Toward this end, his area of study lies at the intersection between biological psychiatry, cognitive neuroscience, and neuropharmacology.

Dr. Skosnik utilizes numerous psychophysiological methods including electroencephalography (EEG), polysomnography (PSG), and eyeblink conditioning (EBC). He is also the Principal Investigator on several projects utilizing neuroimaging methods such as functional magnetic resonance imaging (fMRI) and positron emission tomography (PET). More specifically, he has several parallel lines of research that include: 1) The effect of chronic cannabinoids on measures of cognition, functional connectivity, neural oscillations, and central cannabinoid receptor availability; 2) The effect of acute cannabinoids (THC and cannabidiol) on electrophysiological biomarkers (e.g. gamma oscillations) germane to psychosis; 3) The role of the endogenous cannabinoid system (cannabinoid receptor availability and endocannabinoid levels) in schizophrenia and substance abuse.

Selected Publications (out of more than 50):

• D’Souza, D. C., Radhakrishnan, R., Naganawa, M., Ganesh, S., Nabulsi, N., Najafzadeh, S., Ropchan, J., Ranganathan, M., Cortes-Briones, J.A., Huang, Y., Carson, R., and Skosnik, P. D. (in press). In vivo Evidence of Lower Hippocampal Synaptic Density in Cannabis Use Disorder. Molecular Psychiatry.
• Ganesh, S., Cortes-Briones, J., Ranganathan, M., Radhakrishnan, R., Skosnik, P. D., and D'Souza, D.C. (in press). Psychosis-relevant effects of intravenous delta-9-tetrahydrocannabinol - A mega analysis of individual participant-data from human laboratory studies. Int J Neuropsychopharmacology. doi: 10.1093/ijnp/pyaa031.
• Angarita, G. A., Worhunsky, P. D., Naganawa, M., Toyonaga., T., Nabulsi, N. B., Chiang-Shan, R. Li1., Esterlis, I., Skosnik, P. D., Radhakrishnan, R., Pittman, B., Finnema, S. J., Huang, Y., Carson, R. E., and Malison, R. T. (in re-review). Lower Prefrontal Cortical Synaptic Density in Human Cocaine Users: a 11C-UCB-J PET Study. The Journal of Neuroscience.
• D’Souza, D. C., Cortes-Briones, J. A., Creatura, G., Bluez, G., Thurnauer, H., Deaso, E., Bielen, K., Surti, T., Radhakrishnan, R., Gupta, A., Gupta, S., Cahill, J., Sherif, M. A., Makriyannis, A., Morgan, P. T., Ranganathan, M., and Skosnik, P. D. (2019). Efficacy and Safety of a Fatty Acid Amide Hydrolase Inhibitor (PF-04457845) in the Treatment of Cannabis Withdrawal and Dependence in Men: A Double-Blind, Placebo-Controlled, Parallel Group, Phase 2a Single-Site Randomized Controlled Trial. The Lancet Psychiatry. 6(1), 35-45.
• *Boggs, D. L., *Cortes-Briones, J. A., *Surti, T, Luddy, C, Ranganathan, M., Sewell, A R., D'Souza, D. C, and Skosnik, P. D. (2018). The Dose-Dependent Psychomotor Effects of Intravenous Delta-9-Tetrahydrocannabinol (Δ⁹-THC) in Humans. Journal of Psychopharmacology. 32(12), 1308-1318
• *Sherif, M. A., *Cortes-Briones, J. A., Ranganathan, M., and Skosnik, P. D. (in press). Cannabinoid-Glutamate Interactions and Neural Oscillations: Implications for Psychosis. European Journal of Neuroscience.
• *Skosnik, P. D., *Hajós, M., Cortes-Briones, J. A., Edwards, C. R., Pittman, B., Hoffmann, W. E., Sewell, A. R., D’Souza, D. C., and Ranganathan, M. (2018). Cannabinoid-1 Receptor-Mediated Disruption of Sensory Gating and Neural Oscillations: A Translational Study in Rats and Humans. Neuropharmacology. 135, 412-423.
• Skosnik, P. D. and D'Souza, D. C. (2017). Opposing Effects of Cannabis Use on Electroencephalographic Measures of Auditory Repetition Suppression in Schizophrenia and Healthy Controls. Biol Psychiatry Cogn Neurosci Neuroimaging. 2(3), 209-211.
• Johannesen, J. and Skosnik, P. D. (2017). Applied EEG, Chapter 1.14. In: Kaplan & Sadock’s Comprehensive Textbook of Psychiatry, 10^th Edition, edited by Benjamin J. Sadock, Virginia A. Sadock, and Pedro Ruiz (50th Anniversary Edition). Philadelphia, PA: Lippincott Williams & Wilkins, a Wolters Kluwer business.
• Ranganathan, M., Radhakrishnana, R., Addy, P., Schnakenberg, A., Williams, A., Carbuto, M., Elander, J., Pittman, B., Sewell, A., Skosnik, P. D., D'Souza, D. C. (2017). Tetrahydrocannabinol (THC) impairs encoding but not retrieval of verbal information. Progress in Neuropsychopharmacology & Biological Psychiatry. 79(Pt B), 176-183.
• D’Souza, D. C., Radhakrishnan, R., Sherif, M., Cortes-Briones, J. A, Cahill, J. D., Gupta, S., Skosnik, P. D., and Ranganathan, M. (2016). Cannabinoids and Psychosis. Current Pharmaceutical Design. 22(42), 6380-6391.
• Skosnik, P. D. and Cortes-Briones, J. A. (2016): Targeting the Ecology Within: The Role of the Gut-Brain Axis and Human Microbiota in Drug Addiction. Medical Hypotheses. 93, 77-80.
• Skosnik, P. D., Cortes-Briones, J. A., and Hajos, M. (2016). It’s All in the Rhythm: the Role of Cannabinoids in Neural oscillations and Psychosis. Biological Psychiatry. 79(7), 568-77.
• Ranganathan, M., Skosnik, P. D., and D’Souza, D. C. (2016). Marijuana Madness: Associations Between Cannabinoids and Psychosis. Biological Psychiatry. 79(7), 511-3.
• D'Souza, D. C., Cortes-Briones, J. A., Ranganathan, M., Thurnauer, H., Planeta, B., Neumeister, A., Pittman, B., Morgan, P., Normandin, M., Huang, Y., Carson, R. E., and Skosnik, P. D. (2016). Rapid Changes in CB1 Receptor Availability in Cannabis Dependent Males after Abstinence from Cannabis. Biological Psychiatry: Cognitive Neuroscience and Neuroimaging. 1(1), 60-67.
• Skosnik, P. D. and Cortes-Briones, J. A. (2016): Electroencephalography (EEG) and Cannabis: From Event-Related Potentials (ERPs) to Oscillations, Chapter 80. In: The Neuropathology of Drug Addictions and Substance Misuse: Foundations of Understanding, Tobacco, Alcohol, Cannabinoids and Opioids. Preedy VR. Amsterdam, Netherlands: Elsevier Science.
• Ranganathan, M., Cortes-Briones, J. A., Radhakrishnan, R., Thurnauer, H., Planeta, B., Skosnik, P. D., Gao, H., Labaree, D., Neumeister, A., Pittman, B., Surti, T., Huang, Y., Carson, R. E., and D’Souza, D. C. (2016). Reduced Brain Cannabinoid Receptor Availability In Schizophrenia. Biological Psychiatry. 79(12), 997-1005.
• *Radhakrishnan, R., *Skosnik, P.D., Cortes-Briones, J.A., Sewell, R.A., Carbuto, M., Schnakenberg, A., Williams, A., Cahill, J.D., Bois, F., Gunduz-Bruce, H., Pittman, B., Ranganathan, M., and D’Souza, D.C. (2015). GABA Deficit Enhances the Psychotomimetic Effects of Δ⁹-Tetrahydrocannabinol. Neuropsychopharmacology. 40(8), 2047-56.
• Cortes-Briones, J. A., Cahill, J. D., Skosnik, P. D., Mathalon, D. H., Williams, A., Sewell, R. A., Roach, B. J., Ford, J. M., Ranganathan, M., D'Souza, D. C. (2015). The psychosis-like effects of Δ(9)-tetrahydrocannabinol are associated with increased cortical noise in healthy humans. Biological Psychiatry. 78(11), 805-13.
• Cortes-Briones, J.A., Skosnik, P.D., Mathalon, D., Cahill, J.D., Pittman, B., Williams, A., Sewell, R.A., Ranganathan, M., Roach, B.A., Ford, J., and D’Souza, D.C. (2015). ∆⁹-THC Disrupts Gamma (γ)–Band Neural Oscillations in Humans. Neuropsychopharmacology. 40(9), 2124-34
• Cortes-Briones, J.A., Cahill, J.D., Ranganathan, M., Sewell, R.A., D’Souza, D.C., and Skosnik, P.D. (2015). Testing Differences in the Activity of Event-Related Potential Sources: Important Implications for Clinical Researchers. Clinical Neurophysiology. 126(1), 215-8.
• Skosnik, P. D., Krishnan, G. P., D’Souza, D. C., Hetrick, W. P., and O’Donnell, B. F. (2014). Disrupted Gamma-Band Neural Oscillations During Coherent Motion Perception in Heavy Cannabis Users. Neuropsychopharmacology. 39(13), 3087-99.
• Cheng, H., Skosnik, P. D., Pruce, B. J., Brumbaugh, M. S., Vollmer, J. M., Fridberg, D. J., O’Donnell, B. F., Hetrick, W. P., and Newman, S. D. (2014). Resting state functional MRI reveals distinct brain activity in heavy cannabis users – a multi-voxel pattern analysis. Journal of Psychopharmacology. 28(11), 1030-40.
• Radhakrishnan, R., Addy, P. H., Sewell, R. A., Skosnik, P. D., Ranganathan, M., D’Souza, D. C. Cannabis, Cannabinoids and the link with psychosis. In: Johnson JE (Managing ed), Madras B, Kuhar M (ed). The Effects of Drug Abuse on the Human Nervous System, San Diego, CA: Academic Press (Elsevier), 2014; 423-474.
• Fridberg, D. J., Skosnik, P. D., Hetrick, W. P., and O’Donnell, B. F. (2013). Neural correlates of performance monitoring in chronic cannabis users and cannabis-naïve controls. Journal of Psychopharmacology. 27(6), 515-25.
• Albrecht, D. S., Skosnik, P. D., Vollmer, J. M., Brumbaugh, M. S., Perry, K. M., Mock, B. H., Zheng, Q-H., Federici, L. A., Patton, E. A., Herring, C. M., Yoder, K. K. (2013). Striatal D2/D3 Receptor Availability is Inversely Correlated with Cannabis Consumption in Chronic Cannabis Users. Drug and Alcohol Dependence. 128(1-2), 52-7.
• Sewell, R. A., Schnakenberg, A., Elander, J., Radhakrishnan, R., Williams, A., Skosnik, P. D., Pittman, B., Ranganathan, M., and D'Souza, D. C. (2013). Acute effects of THC on Time Perception in Frequent and Non-frequent Cannabis Users. Psychopharmacology. 226(2), 401-13.
• Skosnik, P. D., D’Souza, D. C., Steinmetz, A. B, Edwards, C. R., Vollmer, J. M., Hetrick, W. P., and O’Donnell, B. F. (2012). The Effect of Chronic Cannabinoids on Broadband EEG Neural Oscillations in Humans. Neuropsychopharmacology. 37(10), 2184-93.
• Ranganathan, M., Schnakenberg, A., Skosnik, P.D., Cohen, B., Munro, T., Pittman, B., Sewell, R.A., and D’Souza, D.C. (2012). Dose-related Behavioral, Subjective, Endocrine and Psychophysiological Effects Of the Kappa Opioid Agonist Salvinorin A in Humans. Biological Psychiatry. 72(10), 871-9.
• Skosnik, P. D., Ranganathan, M., and D’Souza, D. C. (2012). Cannabinoids, Working Memory and Schizophrenia. Biological Psychiatry. 71(8), 662-3.

*Shared first authorship