{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2024,7,15]],"date-time":"2024-07-15T00:23:27Z","timestamp":1721003007647},"reference-count":44,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2021,6,30]],"date-time":"2021-06-30T00:00:00Z","timestamp":1625011200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Entropy"],"abstract":"In recent years, the use of psychedelic drugs to study brain dynamics has flourished due to the unique opportunity they offer to investigate the neural mechanisms of conscious perception. Unfortunately, there are many difficulties to conduct experiments on pharmacologically-induced hallucinations, especially regarding ethical and legal issues. In addition, it is difficult to isolate the neural effects of psychedelic states from other physiological effects elicited by the drug ingestion. Here, we used the DeepDream algorithm to create visual stimuli that mimic the perception of hallucinatory states. Participants were first exposed to a regular video, followed by its modified version, while recording electroencephalography (EEG). Results showed that the frontal region\u2019s activity was characterized by a higher entropy and lower complexity during the modified video, with respect to the regular one, at different time scales. Moreover, we found an increased undirected connectivity and a greater level of entropy in functional connectivity networks elicited by the modified video. These findings suggest that DeepDream and psychedelic drugs induced similar altered brain patterns and demonstrate the potential of adopting this method to study altered perceptual phenomenology in neuroimaging research.<\/jats:p>","DOI":"10.3390\/e23070839","type":"journal-article","created":{"date-parts":[[2021,6,30]],"date-time":"2021-06-30T14:03:19Z","timestamp":1625061799000},"page":"839","source":"Crossref","is-referenced-by-count":4,"title":["Increased Entropic Brain Dynamics during DeepDream-Induced Altered Perceptual Phenomenology"],"prefix":"10.3390","volume":"23","author":[{"ORCID":"http:\/\/orcid.org\/0000-0002-9502-4667","authenticated-orcid":false,"given":"Antonino","family":"Greco","sequence":"first","affiliation":[{"name":"Department of Psychology and Cognitive Science, University of Trento, 38068 Rovereto, Italy"},{"name":"Centre for Integrative Neuroscience, University of T\u00fcbingen, 72076 T\u00fcbingen, Germany"},{"name":"MEG Center, University of T\u00fcbingen, 72076 T\u00fcbingen, Germany"}]},{"ORCID":"http:\/\/orcid.org\/0000-0001-5185-0206","authenticated-orcid":false,"given":"Giuseppe","family":"Gallitto","sequence":"additional","affiliation":[{"name":"Department of Neurology, University Hospital Essen, 45147 Essen, Germany"}]},{"ORCID":"http:\/\/orcid.org\/0000-0002-3596-5780","authenticated-orcid":false,"given":"Marco","family":"D\u2019Alessandro","sequence":"additional","affiliation":[{"name":"Institute of Cognitive Sciences and Technologies, National Research Council, 00185 Rome, Italy"}]},{"ORCID":"http:\/\/orcid.org\/0000-0003-1955-3716","authenticated-orcid":false,"given":"Clara","family":"Rastelli","sequence":"additional","affiliation":[{"name":"Department of Psychology and Cognitive Science, University of Trento, 38068 Rovereto, Italy"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2138","DOI":"10.1073\/pnas.1119598109","article-title":"Neural Correlates of the Psychedelic State as Determined by FMRI Studies with Psilocybin","volume":"109","author":"Erritzoe","year":"2012","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"346","DOI":"10.3389\/fnhum.2015.00346","article-title":"Restructuring Consciousness\u2013the Psychedelic State in Light of Integrated Information Theory","volume":"9","author":"Gallimore","year":"2015","journal-title":"Front. Hum. Neurosci."},{"key":"ref_3","first-page":"20","article-title":"The Entropic Brain: A Theory of Conscious States Informed by Neuroimaging Research with Psychedelic Drugs","volume":"8","author":"Leech","year":"2014","journal-title":"Front. Hum. Neurosci."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"4853","DOI":"10.1073\/pnas.1518377113","article-title":"Neural Correlates of the LSD Experience Revealed by Multimodal Neuroimaging","volume":"113","author":"Muthukumaraswamy","year":"2016","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"204","DOI":"10.3389\/fnhum.2014.00204","article-title":"The Effects of Psilocybin and MDMA on Between-Network Resting State Functional Connectivity in Healthy Volunteers","volume":"8","author":"Roseman","year":"2014","journal-title":"Front. Hum. Neurosci."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"S233","DOI":"10.1093\/schbul\/sbu036","article-title":"Visual Hallucinations in the Psychosis Spectrum and Comparative Information from Neurodegenerative Disorders and Eye Disease","volume":"40","author":"Waters","year":"2014","journal-title":"Schizophr. Bull."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"39","DOI":"10.1016\/j.jcbs.2019.11.004","article-title":"Psychological Flexibility Mediates the Relations between Acute Psychedelic Effects and Subjective Decreases in Depression and Anxiety","volume":"15","author":"Davis","year":"2020","journal-title":"J. Contextual Behav. Sci."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"1261","DOI":"10.1002\/da.23065","article-title":"Historic Psychedelic Drug Trials and the Treatment of Anxiety Disorders","volume":"37","author":"Weston","year":"2020","journal-title":"Depress. Anxiety"},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"3099","DOI":"10.1016\/j.cub.2015.10.014","article-title":"Consciousness and Complexity during Unresponsiveness Induced by Propofol, Xenon, and Ketamine","volume":"25","author":"Sarasso","year":"2015","journal-title":"Curr. Biol."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"20140873","DOI":"10.1098\/rsif.2014.0873","article-title":"Homological Scaffolds of Brain Functional Networks","volume":"11","author":"Petri","year":"2014","journal-title":"J. R. Soc. Interface"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"5442","DOI":"10.1002\/hbm.22562","article-title":"Enhanced Repertoire of Brain Dynamical States during the Psychedelic Experience","volume":"35","author":"Tagliazucchi","year":"2014","journal-title":"Hum. Brain Mapp."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"46421","DOI":"10.1038\/srep46421","article-title":"Increased Spontaneous MEG Signal Diversity for Psychoactive Doses of Ketamine, LSD and Psilocybin","volume":"7","author":"Schartner","year":"2017","journal-title":"Sci. Rep."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"116462","DOI":"10.1016\/j.neuroimage.2019.116462","article-title":"Decreased Directed Functional Connectivity in the Psychedelic State","volume":"209","author":"Barnett","year":"2020","journal-title":"NeuroImage"},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1038\/s41598-017-16316-2","article-title":"A Deep-Dream Virtual Reality Platform for Studying Altered Perceptual Phenomenology","volume":"7","author":"Suzuki","year":"2017","journal-title":"Sci. Rep."},{"key":"ref_15","unstructured":"Mordvintsev, A., Olah, C., and Tyka, M. (2015, June 17). Inceptionism: Going Deeper into Neural Networks. Google Research Blog. Available online: http:\/\/Googleresearch.Blogspot.Co.Uk\/2015\/06\/Inceptionism-Going-Deeper-into-Neural.Html."},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Szegedy, C., Liu, W., Jia, Y., Sermanet, P., Reed, S., Anguelov, D., Erhan, D., Vanhoucke, V., and Rabinovich, A. (2015, January 7\u201312). Going Deeper with Convolutions. Proceedings of the IEEE Conference on Computer Vision and pattern Recognition, Boston, MA, USA.","DOI":"10.1109\/CVPR.2015.7298594"},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"9","DOI":"10.1016\/j.jneumeth.2003.10.009","article-title":"EEGLAB: An Open Source Toolbox for Analysis of Single-Trial EEG Dynamics Including Independent Component Analysis","volume":"134","author":"Delorme","year":"2004","journal-title":"J. Neurosci. Methods"},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"97","DOI":"10.3389\/fnins.2018.00097","article-title":"The Harvard Automated Processing Pipeline for Electroencephalography (HAPPE): Standardized Processing Software for Developmental and High-Artifact Data","volume":"12","author":"Wilkinson","year":"2018","journal-title":"Front. Neurosci."},{"key":"ref_19","unstructured":"Mullen, T. (2012). CleanLine EEGLAB Plugin. San Diego CA: Neuroimaging Inform. Tools Resour. Clgh. (NITRC), Available online: https:\/\/www.nitrc.org\/projects\/cleanline."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1129","DOI":"10.1162\/neco.1995.7.6.1129","article-title":"An Information-Maximization Approach to Blind Separation and Blind Deconvolution","volume":"7","author":"Bell","year":"1995","journal-title":"Neural Comput."},{"key":"ref_21","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1016\/j.neuroimage.2019.05.026","article-title":"ICLabel: An Automated Electroencephalographic Independent Component Classifier, Dataset, and Website","volume":"198","author":"Makeig","year":"2019","journal-title":"NeuroImage"},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"1","DOI":"10.1155\/2011\/156869","article-title":"FieldTrip: Open Source Software for Advanced Analysis of MEG, EEG, and Invasive Electrophysiological Data","volume":"2011","author":"Oostenveld","year":"2011","journal-title":"Comput. Intell. Neurosci."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"174102","DOI":"10.1103\/PhysRevLett.88.174102","article-title":"Permutation Entropy: A Natural Complexity Measure for Time Series","volume":"88","author":"Bandt","year":"2002","journal-title":"Phys. Rev. Lett."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"810","DOI":"10.1093\/bja\/aen290","article-title":"Permutation Entropy of the Electroencephalogram: A Measure of Anaesthetic Drug Effect","volume":"101","author":"Olofsen","year":"2008","journal-title":"Br. J. Anaesth."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"022911","DOI":"10.1103\/PhysRevE.87.022911","article-title":"Weighted-Permutation Entropy: A Complexity Measure for Time Series Incorporating Amplitude Information","volume":"87","author":"Fadlallah","year":"2013","journal-title":"Phys. Rev. E"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"154102","DOI":"10.1103\/PhysRevLett.99.154102","article-title":"Distinguishing Noise from Chaos","volume":"99","author":"Rosso","year":"2007","journal-title":"Phys. Rev. Lett."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"1055","DOI":"10.3390\/e13061055","article-title":"Distances in Probability Space and the Statistical Complexity Setup","volume":"13","author":"Kowalski","year":"2011","journal-title":"Entropy"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"42","DOI":"10.1016\/j.physa.2011.07.030","article-title":"Causality and the Entropy\u2013Complexity Plane: Robustness and Missing Ordinal Patterns","volume":"391","author":"Rosso","year":"2012","journal-title":"Phys. A Stat. Mech. Its Appl."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"4677","DOI":"10.3390\/e16084677","article-title":"Entropy-Complexity Characterization of Brain Development in Chickens","volume":"16","author":"Montani","year":"2014","journal-title":"Entropy"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"75","DOI":"10.1109\/TIT.1976.1055501","article-title":"On the Complexity of Finite Sequences","volume":"22","author":"Lempel","year":"1976","journal-title":"IEEE Trans. Inf. Theory"},{"key":"ref_31","doi-asserted-by":"crossref","unstructured":"Viol, A., Palhano-Fontes, F., Onias, H., de Araujo, D.B., H\u00f6vel, P., and Viswanathan, G.M. (2019). Characterizing Complex Networks Using Entropy-Degree Diagrams: Unveiling Changes in Functional Brain Connectivity Induced by Ayahuasca. Entropy, 21.","DOI":"10.3390\/e21020128"},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1016\/j.jneumeth.2007.03.024","article-title":"Nonparametric Statistical Testing of EEG-and MEG-Data","volume":"164","author":"Maris","year":"2007","journal-title":"J. Neurosci. Methods"},{"key":"ref_33","doi-asserted-by":"crossref","unstructured":"Cohen, J. (2013). Statistical Power Analysis for the Behavioral Sciences, Academic Press.","DOI":"10.4324\/9780203771587"},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"677","DOI":"10.1162\/jocn_a_01068","article-title":"Decoding Dynamic Brain Patterns from Evoked Responses: A Tutorial on Multivariate Pattern Analysis Applied to Time Series Neuroimaging Data","volume":"29","author":"Grootswagers","year":"2017","journal-title":"J. Cogn. Neurosci."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"2550","DOI":"10.1002\/hbm.21381","article-title":"Seeing with the Eyes Shut: Neural Basis of Enhanced Imagery Following Ayahuasca Ingestion","volume":"33","author":"Ribeiro","year":"2012","journal-title":"Hum. Brain Mapp."},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"93","DOI":"10.1007\/s00213-006-0358-7","article-title":"Increased Frontal and Paralimbic Activation Following Ayahuasca, the Pan-Amazonian Inebriant","volume":"186","author":"Riba","year":"2006","journal-title":"Psychopharmacology"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"70","DOI":"10.1016\/j.jphysparis.2006.10.001","article-title":"A Free Energy Principle for the Brain","volume":"100","author":"Friston","year":"2006","journal-title":"J. Physiol. Paris"},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1017\/S0140525X12000477","article-title":"Whatever next? Predictive Brains, Situated Agents, and the Future of Cognitive Science","volume":"36","author":"Clark","year":"2013","journal-title":"Behav. Brain Sci."},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"815","DOI":"10.1098\/rstb.2005.1622","article-title":"A Theory of Cortical Responses","volume":"360","author":"Friston","year":"2005","journal-title":"Philos. Trans. R. Soc. B Biol. Sci."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"127","DOI":"10.1038\/nrn2787","article-title":"The Free-Energy Principle: A Unified Brain Theory?","volume":"11","author":"Friston","year":"2010","journal-title":"Nat. Rev. Neurosci."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"390","DOI":"10.1016\/j.tics.2012.05.003","article-title":"Cortical Oscillations and Sensory Predictions","volume":"16","author":"Arnal","year":"2012","journal-title":"Trends Cogn. Sci."},{"key":"ref_42","doi-asserted-by":"crossref","unstructured":"Friston, K.J. (2019). Waves of Prediction. PLoS Biol., 17.","DOI":"10.1371\/journal.pbio.3000426"},{"key":"ref_43","doi-asserted-by":"crossref","unstructured":"Mediano, P.A., Rosas, F.E., Timmermann, C., Roseman, L., Nutt, D.J., Feilding, A., Kaelen, M., Kringelbach, M.L., Barrett, A.B., and Seth, A.K. (2020). Effects of External Stimulation on Psychedelic State Neurodynamics. bioRxiv.","DOI":"10.1101\/2020.11.01.356071"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"15171","DOI":"10.1523\/JNEUROSCI.2063-13.2013","article-title":"Broadband Cortical Desynchronization Underlies the Human Psychedelic State","volume":"33","author":"Muthukumaraswamy","year":"2013","journal-title":"J. Neurosci."}],"container-title":["Entropy"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1099-4300\/23\/7\/839\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2024,7,14]],"date-time":"2024-07-14T21:06:37Z","timestamp":1720991197000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1099-4300\/23\/7\/839"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2021,6,30]]},"references-count":44,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2021,7]]}},"alternative-id":["e23070839"],"URL":"https:\/\/doi.org\/10.3390\/e23070839","relation":{},"ISSN":["1099-4300"],"issn-type":[{"value":"1099-4300","type":"electronic"}],"subject":[],"published":{"date-parts":[[2021,6,30]]}}}