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Pouliot JJ, Ward RT, Traiser CM, Chiasson P, Gilbert FE, Keil A. Neurophysiological and Autonomic Dynamics of Threat Processing During Sustained Social Fear Generalization. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.16.589830. [PMID: 38659834 PMCID: PMC11042332 DOI: 10.1101/2024.04.16.589830] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/26/2024]
Abstract
Survival in dynamic environments requires that organisms learn to predict danger from situational cues. One key facet of threat prediction is generalization from a predictive cue to similar cues, ensuring that a cue-outcome contingency is applied beyond the original learning environment. Generalization has been observed in laboratory studies of aversive conditioning: behavioral and physiological processes generalize responses from a stimulus paired with threat (the CS+) to unpaired stimuli, with response magnitudes varying with CS+ similarity. In contrast, work focusing on sensory responses in visual cortex has found a sharpening pattern, in which responses to stimuli closely resembling the CS+ are maximally suppressed, potentially reflecting lateral inhibitory interactions with the CS+ representation. Originally demonstrated with simple visual cues, changes in visuocortical tuning have also been observed in threat generalization learning across facial identities. It is unclear to what extent these visuocortical changes represent transient or sustained effects and if generalization learning requires prior conditioning to the CS+. The present study addressed these questions using EEG and pupillometry in an aversive generalization paradigm involving hundreds of trials using a gradient of facial identities. Visuocortical ssVEP sharpening occurred after dozens of trials of generalization learning without prior differential conditioning, but diminished as learning continued. By contrast, generalization of alpha power suppression, pupil dilation, and self-reported valence and arousal was seen throughout the experiment. Findings are consistent with threat processing models emphasizing the role of changing visucocortical and attentional dynamics when forming, curating, and shaping fear memories as observers continue learning about stimulus-outcome contingencies.
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Affiliation(s)
| | | | - Caitlin M. Traiser
- Center for the Study of Emotion and Attention, University of Florida; Department of Psychology, University of Florida
| | - Payton Chiasson
- Center for the Study of Emotion and Attention, University of Florida; Department of Psychology, University of Florida
| | - Faith E. Gilbert
- Center for the Study of Emotion and Attention, University of Florida; Department of Psychology, University of Florida
| | - Andreas Keil
- Center for the Study of Emotion and Attention, University of Florida; Department of Psychology, University of Florida
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Ahumada L, Panitz C, Traiser C, Gilbert F, Ding M, Keil A. Quantifying Population-level Neural Tuning Functions Using Ricker Wavelets and the Bayesian Bootstrap. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.22.595429. [PMID: 38826264 PMCID: PMC11142194 DOI: 10.1101/2024.05.22.595429] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2024]
Abstract
Experience changes the tuning of sensory neurons, including neurons in retinotopic visual cortex, as evident from work in humans and non-human animals. In human observers, visuo-cortical re-tuning has been studied during aversive generalization learning paradigms, in which the similarity of generalization stimuli (GSs) with a conditioned threat cue (CS+) is used to quantify tuning functions. This work utilized pre-defined tuning shapes reflecting prototypical generalization (Gaussian) and sharpening (Difference-of-Gaussians) patterns. This approach may constrain the ways in which re-tuning can be characterized, for example if tuning patterns do not match the prototypical functions or represent a mixture of functions. The present study proposes a flexible and data-driven method for precisely quantifying changes in neural tuning based on the Ricker wavelet function and the Bayesian bootstrap. The method is illustrated using data from a study in which university students (n = 31) performed an aversive generalization learning task. Oriented gray-scale gratings served as CS+ and GSs and a white noise served as the unconditioned stimulus (US). Acquisition and extinction of the aversive contingencies were examined, while steady-state visual event potentials (ssVEP) and alpha-band (8-13 Hz) power were measured from scalp EEG. Results showed that the Ricker wavelet model fitted the ssVEP and alpha-band data well. The pattern of re-tuning in ssVEP amplitude across the stimulus gradient resembled a generalization (Gaussian) shape in acquisition and a sharpening (Difference-of-Gaussian) shape in an extinction phase. As expected, the pattern of re-tuning in alpha-power took the form of a generalization shape in both phases. The Ricker-based approach led to greater Bayes factors and more interpretable results compared to prototypical tuning models. The results highlight the promise of the current method for capturing the precise nature of visuo-cortical tuning functions, unconstrained by the exact implementation of prototypical a-priori models.
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Affiliation(s)
- Laura Ahumada
- Department of Psychology, University of Florida, Gainesville, Florida 32611, USA
| | - Christian Panitz
- Department of Psychology, University of Florida, Gainesville, Florida 32611, USA
- Department of Psychology, University of Bremen, 28359 Bremen, Germany
| | - Caitlin Traiser
- Department of Psychology, University of Florida, Gainesville, Florida 32611, USA
| | - Faith Gilbert
- Department of Psychology, University of Florida, Gainesville, Florida 32611, USA
| | - Mingzhou Ding
- J. Crayton Pruitt Family Department of Biomedical Engineering, University of Florida, Gainesville, Florida 32611, USA
| | - Andreas Keil
- Department of Psychology, University of Florida, Gainesville, Florida 32611, USA
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Bachmann T. What do the pre-stimulus brain-process markers really mean vis-à-vis the NCC?: A commentary on "Beyond task response-Pre-stimulus activity modulates contents of consciousness" by Northoff, Zilio, and Zhang. Phys Life Rev 2024; 50:7-9. [PMID: 38762980 DOI: 10.1016/j.plrev.2024.05.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2024] [Accepted: 05/13/2024] [Indexed: 05/21/2024]
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Farkas AH, Ward RT, Gilbert FE, Pouliot J, Chiasson P, McIlvanie S, Traiser C, Riels K, Mears R, Keil A. Auditory aversive generalization learning prompts threat-specific changes in alpha-band activity. Cereb Cortex 2024; 34:bhae099. [PMID: 38517176 DOI: 10.1093/cercor/bhae099] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 02/09/2024] [Accepted: 02/10/2024] [Indexed: 03/23/2024] Open
Abstract
Pairing a neutral stimulus with aversive outcomes prompts neurophysiological and autonomic changes in response to the conditioned stimulus (CS+), compared to cues that signal safety (CS-). One of these changes-selective amplitude reduction of parietal alpha-band oscillations-has been reliably linked to processing of visual CS+. It is, however, unclear to what extent auditory conditioned cues prompt similar changes, how these changes evolve as learning progresses, and how alpha reduction in the auditory domain generalizes to similar stimuli. To address these questions, 55 participants listened to three sine wave tones, with either the highest or lowest pitch (CS+) being associated with a noxious white noise burst. A threat-specific (CS+) reduction in occipital-parietal alpha-band power was observed similar to changes expected for visual stimuli. No evidence for aversive generalization to the tone most similar to the CS+ was observed in terms of alpha-band power changes, aversiveness ratings, or pupil dilation. By-trial analyses found that selective alpha-band changes continued to increase as aversive conditioning continued, beyond when participants reported awareness of the contingencies. The results support a theoretical model in which selective alpha power represents a cross-modal index of continuous aversive learning, accompanied by sustained sensory discrimination of conditioned threat from safety cues.
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Affiliation(s)
- Andrew H Farkas
- Department of Psychology, University of Florida, 945 Center Dr., P.O. Box 112250, Gainesville, FL 32611
| | - Richard T Ward
- Department of Psychology, University of Florida, 945 Center Dr., P.O. Box 112250, Gainesville, FL 32611
| | - Faith E Gilbert
- Department of Psychology, University of Florida, 945 Center Dr., P.O. Box 112250, Gainesville, FL 32611
| | - Jourdan Pouliot
- Department of Psychology, University of Florida, 945 Center Dr., P.O. Box 112250, Gainesville, FL 32611
| | - Payton Chiasson
- Department of Psychology, University of Florida, 945 Center Dr., P.O. Box 112250, Gainesville, FL 32611
| | - Skylar McIlvanie
- Department of Psychology, University of Florida, 945 Center Dr., P.O. Box 112250, Gainesville, FL 32611
| | - Caitlin Traiser
- Department of Psychology, University of Florida, 945 Center Dr., P.O. Box 112250, Gainesville, FL 32611
| | - Kierstin Riels
- Department of Psychology, University of Florida, 945 Center Dr., P.O. Box 112250, Gainesville, FL 32611
| | - Ryan Mears
- Department of Psychology, University of Florida, 945 Center Dr., P.O. Box 112250, Gainesville, FL 32611
| | - Andreas Keil
- Department of Psychology, University of Florida, 945 Center Dr., P.O. Box 112250, Gainesville, FL 32611
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De Filippo R, Schmitz D. Synthetic surprise as the foundation of the psychedelic experience. Neurosci Biobehav Rev 2024; 157:105538. [PMID: 38220035 PMCID: PMC10839673 DOI: 10.1016/j.neubiorev.2024.105538] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2023] [Revised: 01/03/2024] [Accepted: 01/05/2024] [Indexed: 01/16/2024]
Abstract
Psychedelic agents, such as LSD and psilocybin, induce marked alterations in consciousness via activation of the 5-HT2A receptor (5-HT2ARs). We hypothesize that psychedelics enforce a state of synthetic surprise through the biased activation of the 5-HTRs system. This idea is informed by recent insights into the role of 5-HT in signaling surprise. The effects on consciousness, explained by the cognitive penetrability of perception, can be described within the predictive coding framework where surprise corresponds to prediction error, the mismatch between predictions and actual sensory input. Crucially, the precision afforded to the prediction error determines its effect on priors, enabling a dynamic interaction between top-down expectations and incoming sensory data. By integrating recent findings on predictive coding circuitry and 5-HT2ARs transcriptomic data, we propose a biological implementation with emphasis on the role of inhibitory interneurons. Implications arise for the clinical use of psychedelics, which may rely primarily on their inherent capacity to induce surprise in order to disrupt maladaptive patterns.
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Affiliation(s)
- Roberto De Filippo
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität Berlin, and Berlin Institute of Health, Neuroscience Research Center, 10117 Berlin, Germany.
| | - Dietmar Schmitz
- Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität Berlin, and Berlin Institute of Health, Neuroscience Research Center, 10117 Berlin, Germany; German Center for Neurodegenerative Diseases (DZNE) Berlin, 10117 Berlin, Germany; Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität Berlin, and Berlin Institute of Health, Einstein Center for Neuroscience, 10117 Berlin, Germany; Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität Berlin, and Berlin Institute of Health, NeuroCure Cluster of Excellence, 10117 Berlin, Germany; Humboldt-Universität zu Berlin, Bernstein Center for Computational Neuroscience, Philippstr. 13, 10115 Berlin, Germany
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Codispoti M, De Cesarei A, Ferrari V. Alpha-band oscillations and emotion: A review of studies on picture perception. Psychophysiology 2023; 60:e14438. [PMID: 37724827 DOI: 10.1111/psyp.14438] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2023] [Revised: 08/04/2023] [Accepted: 08/24/2023] [Indexed: 09/21/2023]
Abstract
Although alpha-band activity has long been a focus of psychophysiological research, its modulation by emotional value during picture perception has only recently been studied systematically. Here, we review these studies and report that the most consistent alpha oscillatory pattern indexing emotional processing is an enhanced desynchronization (ERD) over posterior sensors when viewing emotional compared with neutral pictures. This enhanced alpha ERD is not specific to unpleasant picture content, as previously proposed for other measures of affective response, but has also been observed for pleasant stimuli. Evidence suggests that this effect is not confined to the alpha band but that it also involves a desynchronization of the lower beta frequencies (8-20 Hz). The emotional modulation of alpha ERD occurs even after massive stimulus repetition and when emotional cues serve as task-irrelevant distractors, consistent with the hypothesis that evaluative processes are mandatory in emotional picture processing. A similar enhanced ERD has been observed for other significant cues (e.g., conditioned aversive stimuli, or in anticipation of a potential threat), suggesting that it reflects cortical excitability associated with the engagement of the motivational systems.
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Affiliation(s)
| | | | - Vera Ferrari
- Department of Medicine and Surgery, University of Parma, Parma, Italy
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Pirazzini G, Starita F, Ricci G, Garofalo S, di Pellegrino G, Magosso E, Ursino M. Changes in brain rhythms and connectivity tracking fear acquisition and reversal. Brain Struct Funct 2023:10.1007/s00429-023-02646-7. [PMID: 37129622 DOI: 10.1007/s00429-023-02646-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 04/17/2023] [Indexed: 05/03/2023]
Abstract
Fear conditioning is used to investigate the neural bases of threat and anxiety, and to understand their flexible modifications when the environment changes. This study aims to examine the temporal evolution of brain rhythms using electroencephalographic signals recorded in healthy volunteers during a protocol of Pavlovian fear conditioning and reversal. Power changes and Granger connectivity in theta, alpha, and gamma bands are investigated from neuroelectrical activity reconstructed on the cortex. Results show a significant increase in theta power in the left (contralateral to electrical shock) portion of the midcingulate cortex during fear acquisition, and a significant decrease in alpha power in a broad network over the left posterior-frontal and parietal cortex. These changes occur since the initial trials for theta power, but require more trials (3/4) to develop for alpha, and are also present during reversal, despite being less pronounced. In both bands, relevant changes in connectivity are mainly evident in the last block of reversal, just when power differences attenuate. No significant changes in the gamma band were detected. We conclude that the increased theta rhythm in the cingulate cortex subserves fear acquisition and is transmitted to other cortical regions via increased functional connectivity allowing a fast theta synchronization, whereas the decrease in alpha power can represent a partial activation of motor and somatosensory areas contralateral to the shock side in the presence of a dangerous stimulus. In addition, connectivity changes at the end of reversal may reflect long-term alterations in synapses necessary to reverse the previously acquired contingencies.
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Affiliation(s)
- Gabriele Pirazzini
- Department of Electrical, Electronic, and Information Engineering "Guglielmo Marconi", University of Bologna, Area di Campus Cesena, Via Dell'Università 50, 47521, Cesena, Italy.
| | - Francesca Starita
- Center for Studies and Research in Cognitive Neuroscience, Department of Psychology "Renzo Canestrari", University of Bologna, 40126, Bologna, Italy
| | - Giulia Ricci
- Department of Electrical, Electronic, and Information Engineering "Guglielmo Marconi", University of Bologna, Area di Campus Cesena, Via Dell'Università 50, 47521, Cesena, Italy
| | - Sara Garofalo
- Center for Studies and Research in Cognitive Neuroscience, Department of Psychology "Renzo Canestrari", University of Bologna, 40126, Bologna, Italy
| | - Giuseppe di Pellegrino
- Center for Studies and Research in Cognitive Neuroscience, Department of Psychology "Renzo Canestrari", University of Bologna, 40126, Bologna, Italy
| | - Elisa Magosso
- Department of Electrical, Electronic, and Information Engineering "Guglielmo Marconi", University of Bologna, Area di Campus Cesena, Via Dell'Università 50, 47521, Cesena, Italy
| | - Mauro Ursino
- Department of Electrical, Electronic, and Information Engineering "Guglielmo Marconi", University of Bologna, Area di Campus Cesena, Via Dell'Università 50, 47521, Cesena, Italy
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