111 results on '"Chait M"'
Search Results
2. Electricity-market price and nuclear power plant shutdown: Evidence from California
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Woo, C.K., Ho, T., Zarnikau, J., Olson, A., Jones, R., Chait, M., Horowitz, I., and Wang, J.
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- 2014
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3. The cumulative effects of predictability on synaptic gain in the auditory processing stream
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Auksztulewicz, R, Barascud, N, Cooray, G, Nobre, A, Chait, M, and Friston, K
- Abstract
Stimulus predictability can lead to substantial modulations of brain activity, such as shifts in sustained magnetic field amplitude, measured with magnetoencephalography. Here, we provide a mechanistic explanation of these effects using MEG data acquired from healthy human volunteers (N=13, 7 female). In a source-level analysis of induced responses, we established the effects of orthogonal predictability manipulations of rapid tone-pip sequences (namely, sequence regularity and alphabet size) along the auditory processing stream. In auditory cortex, regular sequences with smaller alphabets induced greater gamma activity. Furthermore, sequence regularity shifted induced activity in frontal regions towards higher frequencies. To model these effects in terms of the underlying neurophysiology, we used dynamic causal modelling for cross-spectral density and estimated slow fluctuations in neural (postsynaptic) gain. Using the model-based parameters, we accurately explain the sensor-level sustained field amplitude, demonstrating that slow changes in synaptic efficacy — combined with sustained sensory input — can result in profound and sustained effects on neural responses to predictable sensory streams.
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- 2017
4. Neural correlates of auditory figure-ground segregation based on temporal coherence
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Teki S, Nicolas Barascud, Picard S, Payne C, Td, Griffiths, and Chait M
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magnetoencephalography ,Adult ,Auditory Cortex ,Male ,Brain Mapping ,Neuronal Plasticity ,auditory scene analysis ,Original Articles ,intraparietal sulcus ,segregation ,Spatio-Temporal Analysis ,Pattern Recognition, Physiological ,Evoked Potentials, Auditory ,Humans ,Female ,Nerve Net ,Pitch Perception ,Perceptual Masking ,temporal coherence - Abstract
To make sense of natural acoustic environments, listeners must parse complex mixtures of sounds that vary in frequency, space, and time. Emerging work suggests that, in addition to the well-studied spectral cues for segregation, sensitivity to temporal coherence-the coincidence of sound elements in and across time-is also critical for the perceptual organization of acoustic scenes. Here, we examine pre-attentive, stimulus-driven neural processes underlying auditory figure-ground segregation using stimuli that capture the challenges of listening in complex scenes where segregation cannot be achieved based on spectral cues alone. Signals ("stochastic figure-ground": SFG) comprised a sequence of brief broadband chords containing random pure tone components that vary from 1 chord to another. Occasional tone repetitions across chords are perceived as "figures" popping out of a stochastic "ground." Magnetoencephalography (MEG) measurement in naïve, distracted, human subjects revealed robust evoked responses, commencing from about 150 ms after figure onset that reflect the emergence of the "figure" from the randomly varying "ground." Neural sources underlying this bottom-up driven figure-ground segregation were localized to planum temporale, and the intraparietal sulcus, demonstrating that this area, outside the "classic" auditory system, is also involved in the early stages of auditory scene analysis."
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- 2016
5. The locality phenomenon in the analysis of self-similar network traffic flows
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Millan, G., primary, Chait, M., additional, and Lefranc, G., additional
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- 2016
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6. Integration and Test of a 2nd Generation Dual Purpose Pulse Forming Network into the P&E HWIL SIL
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TACOM RESEARCH DEVELOPMENT AND ENGINEERING CENTER WARREN MI, Barshaw, E. J., White, J., Danielson, G., Chait, M. J., Frazier, G., Dixon, B., Marinos, B., Milner, D., TACOM RESEARCH DEVELOPMENT AND ENGINEERING CENTER WARREN MI, Barshaw, E. J., White, J., Danielson, G., Chait, M. J., Frazier, G., Dixon, B., Marinos, B., and Milner, D.
- Abstract
A 2nd Generation Dual Purpose Pulse Forming Network (DP-PFN) has been developed to power both the Electro-Thermal-Chemical (ETC)/Electro-Thermal-Ignition (ETI) lethality capability and the Electro-Magnetic Armor (EMA) survivability capability improvements envisioned for future hybrid-electric vehicles. ETI decreases the ignition variability associated with the launching of conventional munitions by roughly a factor of ten which, in conjunction with the systems ballistic computer, greatly enhances hit probability of the round. ETC provides maximum performance in all conditions, including temperature compensation, resulting in increased lethality and range with higher average muzzle velocities. EMA uses stored electric energy to disrupt a shaped-charge jet and reduce it,s depth of penetration. The second generation DP-PFN for driving both ETI/ETC and EMA emulators is scheduled to be integrated into the Power and Energy (P&E) Hardware-in-the-Loop (HWIL) System Integration laboratory (SIL) in Santa Clara, California in 2006. The DP-PFN is capable of providing either the short pulse lengths required by the EMA or the considerably longer pulse lengths required by the ETI/ ETC Gun as well as emulating various degraded functionality states such as loss of individual capacitors. Integration of this DP-PFN marks another great milestone for the SIL, ensuring that it continues to be capable of emulating all the major hybrid electric mobility functions of a ground combat vehicle as well as the major lethality and survivability electrical loads. This paper describes the DP-PFN components, the overall DP-PFN design philosophy and the planned integration and testing of the DP-PFN in the P&E HWIL SIL., Prepared in cooperation with SAIC, Beltsville, MD. Presented at the International Symposium on Electromagnetic Launch Technology (EML) [13th], held in Potsdam, Brandenburg, Germany 22-25 May 2006. Published in IEEE Transactions on Magnetics, v43, n1, p226-229, Jan 2007. The original document contains color images.
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- 2006
7. Effets de la latéralisation corticale auditive dans la perception de la parole
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Saoud, H., primary, Truy, E., additional, Bertasi, E., additional, Chait, M., additional, Gosse, G., additional, and Giraud, A., additional
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- 2012
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8. Integration and Test of a Dual Purpose Pulse Forming Network into the P&E HWIL SIL
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ARMY TANK-AUTOMOTIVE COMMAND WARREN MI, Bradshaw, E., Chait, M., Danielson, G., Herrera, D., Khalil, G., Leathers, E., Argo, P., Bard, A., Frazier, G., Marinos, B., ARMY TANK-AUTOMOTIVE COMMAND WARREN MI, Bradshaw, E., Chait, M., Danielson, G., Herrera, D., Khalil, G., Leathers, E., Argo, P., Bard, A., Frazier, G., and Marinos, B.
- Abstract
A Dual Purpose Pulse Forming Network (DP-PFN) has been developed to power both the Electro-Thermal- Chemical (ETC)/Electro-Thermal-Ignition (ETI) lethality capability and the Electro-Magnetic Armor (EMA) survivability capability improvements envisioned for future hybrid-electric combat vehicles. The DP-PFN is capable of providing two types of energy pulses to accommodate gun and armor loads: extremely short pulse lengths for the EMA, or longer pulse lengths for the ETI/ETC Gun. This capability of the DP-PFN allows for emulation of three major hybrid-electric, lethality, and survivability functions of an electrically-driven ground combat vehicle., See also ADM001736, Proceedings for the Army Science Conference (24th) Held on 29 November - 2 December 2004 in Orlando, Florida. The original document contains color images.
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- 2004
9. Brain Bases for Auditory Stimulus-Driven Figure-Ground Segregation
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Teki, S., primary, Chait, M., additional, Kumar, S., additional, von Kriegstein, K., additional, and Griffiths, T. D., additional
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- 2011
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10. Research on Improving Metallized Polypropylene Capacitors to Increase Energy Density
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White, J., primary, Paschen, J., additional, Chait, M., additional, Barshaw, E., additional, Cornette, J., additional, Bustamante, J., additional, Dorr, G., additional, Folli, F., additional, Biltchick, D., additional, Borrelli, G., additional, Picci, G., additional, and Rabuffi, M., additional
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- 2007
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11. High Energy Density (HED) Biaxial-Oriented Poly-Propylene (BOPP) Capacitors for Pulsed Power Applications
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White, J., primary, Paschen, J., additional, Chait, M., additional, Barshaw, E., additional, Cornette, J., additional, Bustamante, J., additional, Dorr, G., additional, Folli, F., additional, Biltchick, D., additional, Borrelli, G., additional, Picci, G., additional, and Rabuffi, M., additional
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- 2007
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12. Processing Asymmetry of Transitions between Order and Disorder in Human Auditory Cortex
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Chait, M., primary, Poeppel, D., additional, de Cheveigne, A., additional, and Simon, J. Z., additional
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- 2007
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13. High Energy Density (HED) Biaxially-Oriented Poly-Propylene (BOPP) Capacitors For Pulse Power Applications
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Barshaw, E. J., primary, White, J., additional, Chait, M. J., additional, Cornette, J. B., additional, Bustamante, J., additional, Folli, F., additional, Biltchick, D., additional, Borelli, G., additional, Picci, G., additional, and Rabuffi, M., additional
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- 2007
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14. Integration and Test of a Second Generation Dual Purpose Pulse Forming Network Into the P&E HWIL SIL
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Barshaw, E. J., primary, White, J., additional, Danielson, G., additional, Chait, M. J., additional, Frazier, G., additional, Dixon, B., additional, Marinos, B., additional, and Milner, D., additional
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- 2007
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15. Human Auditory Cortical Processing of Changes in Interaural Correlation
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Chait, M., primary
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- 2005
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16. Proton pump inhibitor-refractory gastroesophageal reflux disease: challenges and solutions
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Mermelstein J, Chait Mermelstein A, and Chait MM
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PPI failure ,Resistant GERD ,acid-related diseases ,Diseases of the digestive system. Gastroenterology ,RC799-869 - Abstract
Joseph Mermelstein,1 Alanna Chait Mermelstein,2 Maxwell M Chait3 1Gasteroenterology and Nutrition Service, Department of Medicine, Memorial Sloan Kettering Cancer Center, New York, NY, USA; 2Department of Psychiatry and Behavioral Sciences, Memorial Sloan Kettering Cancer Center, New York, NY, USA; 3Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USA Abstract: A significant percentage of patients with gastroesophageal reflux disease (GERD) will not respond to proton pump inhibitor (PPI) therapy. The causes of PPI-refractory GERD are numerous and diverse, and include adherence, persistent acid, functional disorders, nonacid reflux, and PPI bioavailability. The evaluation should start with a symptom assessment and may progress to imaging, endoscopy, and monitoring of esophageal pH, impedance, and bilirubin. There are a variety of pharmacologic and procedural interventions that should be selected based on the underlying mechanism of PPI failure. Pharmacologic treatments can include antacids, prokinetics, alginates, bile acid binders, reflux inhibitors, and antidepressants. Procedural options include laparoscopic fundoplication and LINX as well as endoscopic procedures, such as transoral incisionless fundoplication and Stretta. Several alternative and complementary treatments of possible benefit also exist. Keywords: PPI failure, resistant GERD, acid-related diseases, gastroesophageal reflux disease, acid reflux, proton pump inhibitors
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- 2018
17. LINING OF COMPRESSION SET TEST FIXTURES. Interim Report.
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Chait, M. J., primary
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- 1971
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18. Proton pump inhibitors for the treatment of patients with erosive esophagitis and gastroesophageal reflux disease: current evidence and safety of dexlansoprazole
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Mermelstein J, Mermelstein AC, and Chait MM
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dexlansoprazole ,proton pump inhibitors ,gastroesophageal reflux disease ,erosive esophagitis ,Diseases of the digestive system. Gastroenterology ,RC799-869 - Abstract
Joseph Mermelstein,1 Alanna Chait Mermelstein,2 Maxwell M Chait,3 1Department of Medicine, Mount Sinai Beth Israel/Icahn School of Medicine, 2Department of Psychiatry, New York Presbyterian Hospital/Weill Cornell Medicine, 3Department of Medicine, Columbia University College of Physicians and Surgeons, New York, NY, USA Abstract: Gastroesophageal reflux disease is the most common upper gastroenterology disorder in the US. It is associated with a variety of complications and significantly impacts quality of life. Proton pump inhibitors are the most effective treatment. Dexlansoprazole modified release (MR) is a proton pump inhibitor that employs a novel release formulation that prolongs its absorption and allows for more flexibility in dosing. Dexlansoprazole MR can be dosed without regard to food intake or time of day, and once-daily dosing may replace twice-daily dosing of other agents. Dexlansoprazole MR is effective for healing and maintenance of erosive esophagitis, and for the treatment of nonerosive disease, including nocturnal gastroesophageal reflux disease. Dexlansoprazole MR is safe and well tolerated, and can improve quality of life. Keywords: dexlansoprazole, proton pump inhibitors, gastroesophageal reflux disease, erosive esophagitis
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- 2016
19. CEA in colonic lavage of individuals at high risk for large bowel cancer
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Poleski, H.H., primary, Blattner, W.A., additional, Chait, M., additional, Winawer, S.J., additional, Fleisher, M., additional, Schwartz, M.K., additional, Fraumeni, J.F., additional, and Lipkin, M., additional
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- 1978
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20. Brain responses track patterns in sound
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Southwell, Rosemary, Chait, M., and Friston, K.
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617.8 - Abstract
This thesis uses specifically structured sound sequences, with electroencephalography (EEG) recording and behavioural tasks, to understand how the brain forms and updates a model of the auditory world. Experimental chapters 3-7 address different effects arising from statistical predictability, stimulus repetition and surprise. Stimuli comprised tone sequences, with frequencies varying in regular or random patterns. In Chapter 3, EEG data demonstrate fast recognition of predictable patterns, shown by an increase in responses to regular relative to random sequences. Behavioural experiments investigate attentional capture by stimulus structure, suggesting that regular sequences are easier to ignore. Responses to repetitive stimulation generally exhibit suppression, thought to form a building block of regularity learning. However, the patterns used in this thesis show the opposite effect, where predictable patterns show a strongly enhanced brain response, compared to frequency-matched random sequences. Chapter 4 presents a study which reconciles auditory sequence predictability and repetition in a single paradigm. Results indicate a system for automatic predictability monitoring which is distinct from, but concurrent with, repetition suppression. The brain's internal model can be investigated via the response to rule violations. Chapters 5 and 6 present behavioural and EEG experiments where violations are inserted in the sequences. Outlier tones within regular sequences evoked a larger response than matched outliers in random sequences. However, this effect was not present when the violation comprised a silent gap. Chapter 7 concerns the ability of the brain to update an existing model. Regular patterns transitioned to a different rule, keeping the frequency content constant. Responses show a period of adjustment to the rule change, followed by a return to tracking the predictability of the sequence. These findings are consistent with the notion that the brain continually maintains a detailed representation of ongoing sensory input and that this representation shapes the processing of incoming information.
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- 2019
21. The role of the locus coeruleus noradrenergic system in tracking the statistics of rapid sound sequences
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Zhao, S., Chait, M., and Dick, F.
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612.8 - Abstract
The sensory world is full of uncertainty; most perception-relevant statistics are highly dynamic, featuring frequently-changing patterns. Rapid adaptation to the everchanging world requires brain sensitivity to environmental changes and resetting of functional neural networks as needed. Norepinephrine (NE) is proposed to mediate this process by initiating functional resetting (Dayan and Yu, 2006; Sara and Bouret, 2012) via the Locus Coeruleus (LC)-NE system. This doctoral thesis employs pupil diameter measurements – a reliable indicator of NE neural activity in the LC (Aston-Jones and Cohen, 2005; Joshi et al. 2016). Human participants listened to sequences of adjoined 50ms tone-pips (adapted from Barascud et al., 2016) containing transitions from random to regular frequency patterns and vice-versa. Participants were instructed to detect occasionally inserted silent gaps, ensuring attention to the auditory stream, not the transition itself. Although both transitions (regular-to-random and random-to-regular) are clearly detectable behaviourally and evoke strong MEG (Barascud et al., 2016), only violations of regularity (prediction errors) appear to elicit pupil responses. Noteworthily, this response is driven by pattern changes and not merely deviant detection. However, stimuli containing pattern emergences (precision increase) evoke no measurable pupil response; this is not due to pre-transition pupillary saturation, as transitions from random patterns to repeating single tones (random-to-repeating) evoke transient pupil dilation. Only when subjects actively reported changes in button-press did random-to-regular transitions evoke pupil dilations. Investigating the effect of task on evoked pupil responses found no response if subjects were not continuously tracking the sequences, e.g. with attention directed to visual or tactile stimuli. Multiple self-replications of these findings provide robust evidence that NE release acts as an automatic switch, resetting the brain’s internal model of the sensory environment and demonstrating that the unexpected uncertainty signalling process operates over much faster timescales than previously known, implicating NE in the fundamental bases of perception.
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- 2018
22. Sensitivity to temporal structure supports auditory scene analysis : a psychophysics and magnetoencephalography investigation
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Andreou, L.-V., Chait, M., and Dakin, S.
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617.8 - Abstract
The auditory system has developed very sophisticated mechanisms to seek regularities and to extract temporal patterns in sound. This is widely acknowledged yet the mechanisms governing these processes are not fully understood. The purpose of the thesis is to systematically explore how these mechanisms work and what computations they are operating under as well as which regularities we are sensitive to and how this sensitivity plays a role in everyday listening. The thesis is divided into five chapters. In Chapter 1, I review the relevant cognitive and neuroimaging literature. In Chapter 2, I employ magnetoencephalography (MEG) to study the extent to which listeners adapt to temporal structure of acoustic sequences. I demonstrate that the auditory cortex is sensitive to the temporal structure of isochronous sequences, even when this information is not behaviourally relevant. Furthermore, I present evidence that the temporal structure of regular sequences is not learnt as precisely, however, active attending to regular sequences results in improved adaptation. In Chapter 3, I look at a very simple multi-object environment and use an objective measure of performance on a difficult pattern detection task. I show that temporal regularity facilitates stream segregation, but that the effect of temporal regularity as a cue for segregation is limited to relatively fast rates and to situations where frequency separation is insufficient for segregation. In Chapter 4, I show, in the context of a change detection task, that even in complex auditory scenes, sensitivity to temporal regularity is critical to our ability to analyse and detect changes in a dynamic soundscape. In the concluding chapter, I discuss the predictive modelling view of the auditory system and the functional role of temporal structure in auditory scene analysis.
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- 2016
23. Auditory pattern detection
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Barascud, Nicolas and Chait, M.
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617.8 - Abstract
The work presented in this doctoral thesis uses behavioural methods and neuroimaging to investigate how human listeners detect patterns and statistical regularities in complex sound sequences. Temporal pattern analysis is essential to sensory processing, especially listening, since most auditory signals only have meaning as sequences over time. Previous evidence suggests that the brain is sensitive to the statistics of sensory stimulation. However, the process through which this sensitivity arises is largely unknown. This dissertation is organised as follows: Chapter 1 reviews fundamental principles of auditory scene analysis and existing models of regularity processing to constrain the scientific questions being addressed. Chapter 2 introduces the two neuroimaging techniques used in this work, magnetoencephalography (MEG) and functional Magnetic Resonance Imaging (fMRI). Chapters 3-6 are experimental sections. In Chapter 3, a novel stimulus is presented that allows probing listeners’ sensitivity to the emergence and disappearance of complex acoustic patterns. Pattern detection performance is evaluated behaviourally, and systematically compared with the predictions of an ideal observer model. Chapters 4 and 5 describe the brain responses measured during processing of those complex regularities using MEG and fMRI, respectively. Chapter 6 presents an extension of the main behavioural task to the visual domain, which allows pattern detection to be compared in audition and vision. Chapter 7 concludes with a general discussion of the experimental results and provides directions for future research. Overall, the results are consistent with predictive coding accounts of perceptual inference and provide novel neurophysiological evidence for the brain's exquisite sensitivity to stimulus context and its capacity to encode high-order structure in sensory signals.
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- 2014
24. Distinct antibody responses to SARS-CoV-2 in children and adults across the COVID-19 clinical spectrum
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Rei Matsumoto, Yun Zhu, Emily M. Mace, Michael Chait, Wen-Hsuan W. Lin, Eldad A. Hod, Didier Decimo, Branka Horvat, Matthew R. Baldwin, Steven B. Wells, Stephen A. Ferrara, Stuart P. Weisberg, Julia Davis-Porada, Pranay Dogra, Donna L. Farber, Debora Stelitano, Emma Idzikowski, Flavia Dei Zotti, Cyrille Mathieu, Francesca T. Bovier, Matteo Porotto, Zachary C. Bitan, Sandeep N. Wontakal, Francesca La Carpia, Anne Moscona, Krystalyn E. Hudson, Joshua I. Gray, Thomas J. Connors, Peter A. Szabo, Joshua D. Milner, Maya Meimei Li Poon, Columbia University Irving Medical Center (CUIMC), University of the Study of Campania Luigi Vanvitelli, Columbia University [New York], Centre International de Recherche en Infectiologie - UMR (CIRI), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), Centre International de Recherche en Infectiologie (CIRI), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Université Jean Monnet - Saint-Étienne (UJM)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS), ANR-20-COVI-0053,CoVarImm,Variation de la réponse immune systémique et muqueuse pendant l'infection par le SRAS-CoV-2 et la convalescence(2020), Mathieu, Cyrille, Weisberg, S. P., Connors, T. J., Zhu, Y., Baldwin, M. R., Lin, W. -H., Wontakal, S., Szabo, P. A., Wells, S. B., Dogra, P., Gray, J., Idzikowski, E., Stelitano, D., Bovier, F. T., Davis-Porada, J., Matsumoto, R., Poon, M. M. L., Chait, M., Mathieu, C., Horvat, B., Decimo, D., Hudson, K. E., Zotti, F. D., Bitan, Z. C., La Carpia, F., Ferrara, S. A., Mace, E., Milner, J., Moscona, A., Hod, E., Porotto, M., and Farber, D. L.
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0301 basic medicine ,ARDS ,[SDV]Life Sciences [q-bio] ,Immunology ,Population ,medicine.disease_cause ,Article ,Serology ,03 medical and health sciences ,0302 clinical medicine ,Immune system ,medicine ,Immunology and Allergy ,Respiratory system ,Young adult ,education ,Coronavirus ,education.field_of_study ,biology ,business.industry ,medicine.disease ,3. Good health ,[SDV] Life Sciences [q-bio] ,030104 developmental biology ,biology.protein ,Antibody ,business ,030215 immunology - Abstract
International audience; Clinical manifestations of COVID-19 caused by the new coronavirus SARS-CoV-2 are associated with age1,2. Adults develop respiratory symptoms, which can progress to acute respiratory distress syndrome (ARDS) in the most severe form, while children are largely spared from respiratory illness but can develop a life-threatening multisystem inflammatory syndrome (MIS-C)3-5. Here, we show distinct antibody responses in children and adults after SARS-CoV-2 infection. Adult COVID-19 cohorts had anti-spike (S) IgG, IgM and IgA antibodies, as well as anti-nucleocapsid (N) IgG antibody, while children with and without MIS-C had reduced breadth of anti-SARS-CoV-2-specific antibodies, predominantly generating IgG antibodies specific for the S protein but not the N protein. Moreover, children with and without MIS-C had reduced neutralizing activity as compared to both adult COVID-19 cohorts, indicating a reduced protective serological response. These results suggest a distinct infection course and immune response in children independent of whether they develop MIS-C, with implications for developing age-targeted strategies for testing and protecting the population.
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- 2020
25. Eye movements track prioritized auditory features in selective attention to natural speech.
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Gehmacher Q, Schubert J, Schmidt F, Hartmann T, Reisinger P, Rösch S, Schwarz K, Popov T, Chait M, and Weisz N
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- Humans, Magnetoencephalography, Eye-Tracking Technology, Ocular Physiological Phenomena, Speech Perception, Cognition, Hearing, Time Factors, Male, Female, Adult, Speech Intelligibility, Speech, Attention, Eye Movements, Auditory Perception
- Abstract
Over the last decades, cognitive neuroscience has identified a distributed set of brain regions that are critical for attention. Strong anatomical overlap with brain regions critical for oculomotor processes suggests a joint network for attention and eye movements. However, the role of this shared network in complex, naturalistic environments remains understudied. Here, we investigated eye movements in relation to (un)attended sentences of natural speech. Combining simultaneously recorded eye tracking and magnetoencephalographic data with temporal response functions, we show that gaze tracks attended speech, a phenomenon we termed ocular speech tracking. Ocular speech tracking even differentiates a target from a distractor in a multi-speaker context and is further related to intelligibility. Moreover, we provide evidence for its contribution to neural differences in speech processing, emphasizing the necessity to consider oculomotor activity in future research and in the interpretation of neural differences in auditory cognition., (© 2024. The Author(s).)
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- 2024
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26. Concurrent Encoding of Sequence Predictability and Event-Evoked Prediction Error in Unfolding Auditory Patterns.
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Hu M, Bianco R, Hidalgo AR, and Chait M
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- Male, Female, Humans, Acoustic Stimulation methods, Evoked Potentials, Auditory physiology, Brain physiology, Magnetoencephalography, Auditory Perception physiology, Auditory Cortex physiology
- Abstract
Human listeners possess an innate capacity to discern patterns within rapidly unfolding sensory input. Core questions, guiding ongoing research, focus on the mechanisms through which these representations are acquired and whether the brain prioritizes or suppresses predictable sensory signals. Previous work, using fast auditory sequences (tone-pips presented at a rate of 20 Hz), revealed sustained response effects that appear to track the dynamic predictability of the sequence. Here, we extend the investigation to slower sequences (4 Hz), permitting the isolation of responses to individual tones. Stimuli were 50 ms tone-pips, ordered into random (RND) and regular (REG; a repeating pattern of 10 frequencies) sequences; Two timing profiles were created: in "fast" sequences, tone-pips were presented in direct succession (20 Hz); in "slow" sequences, tone-pips were separated by a 200 ms silent gap (4 Hz). Naive participants ( N = 22; both sexes) passively listened to these sequences, while brain responses were recorded using magnetoencephalography (MEG). Results unveiled a heightened magnitude of sustained brain responses in REG when compared to RND patterns. This manifested from three tones after the onset of the pattern repetition, even in the context of slower sequences characterized by extended pattern durations (2,500 ms). This observation underscores the remarkable implicit sensitivity of the auditory brain to acoustic regularities. Importantly, brain responses evoked by single tones exhibited the opposite pattern-stronger responses to tones in RND than REG sequences. The demonstration of simultaneous but opposing sustained and evoked response effects reveals concurrent processes that shape the representation of unfolding auditory patterns., Competing Interests: The authors declare no competing financial interests., (Copyright © 2024 Hu et al.)
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- 2024
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27. Cross-Modal Interactions Between Auditory Attention and Oculomotor Control.
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Zhao S, Contadini-Wright C, and Chait M
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- Male, Female, Humans, Sensation, Sound, Auditory Perception physiology, Visual Perception physiology, Eye Movements
- Abstract
Microsaccades are small, involuntary eye movements that occur during fixation. Their role is debated with recent hypotheses proposing a contribution to automatic scene sampling. Microsaccadic inhibition (MSI) refers to the abrupt suppression of microsaccades, typically evoked within 0.1 s after new stimulus onset. The functional significance and neural underpinnings of MSI are subjects of ongoing research. It has been suggested that MSI is a component of the brain's attentional re-orienting network which facilitates the allocation of attention to new environmental occurrences by reducing disruptions or shifts in gaze that could interfere with processing. The extent to which MSI is reflexive or influenced by top-down mechanisms remains debated. We developed a task that examines the impact of auditory top-down attention on MSI, allowing us to disentangle ocular dynamics from visual sensory processing. Participants ( N = 24 and 27; both sexes) listened to two simultaneous streams of tones and were instructed to attend to one stream while detecting specific task "targets." We quantified MSI in response to occasional task-irrelevant events presented in both the attended and unattended streams (frequency steps in Experiment 1, omissions in Experiment 2). The results show that initial stages of MSI are not affected by auditory attention. However, later stages (∼0.25 s postevent onset), affecting the extent and duration of the inhibition, are enhanced for sounds in the attended stream compared to the unattended stream. These findings provide converging evidence for the reflexive nature of early MSI stages and robustly demonstrate the involvement of auditory attention in modulating the later stages., Competing Interests: The authors declare no competing financial interests., (Copyright © 2024 Zhao et al.)
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- 2024
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28. Generalization of auditory expertise in audio engineers and instrumental musicians.
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Caprini F, Zhao S, Chait M, Agus T, Pomper U, Tierney A, and Dick F
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- Humans, Auditory Perception, Pitch Perception, Cognition, Acoustic Stimulation, Music, Speech Perception
- Abstract
From auditory perception to general cognition, the ability to play a musical instrument has been associated with skills both related and unrelated to music. However, it is unclear if these effects are bound to the specific characteristics of musical instrument training, as little attention has been paid to other populations such as audio engineers and designers whose auditory expertise may match or surpass that of musicians in specific auditory tasks or more naturalistic acoustic scenarios. We explored this possibility by comparing students of audio engineering (n = 20) to matched conservatory-trained instrumentalists (n = 24) and to naive controls (n = 20) on measures of auditory discrimination, auditory scene analysis, and speech in noise perception. We found that audio engineers and performing musicians had generally lower psychophysical thresholds than controls, with pitch perception showing the largest effect size. Compared to controls, audio engineers could better memorise and recall auditory scenes composed of non-musical sounds, whereas instrumental musicians performed best in a sustained selective attention task with two competing streams of tones. Finally, in a diotic speech-in-babble task, musicians showed lower signal-to-noise-ratio thresholds than both controls and engineers; however, a follow-up online study did not replicate this musician advantage. We also observed differences in personality that might account for group-based self-selection biases. Overall, we showed that investigating a wider range of forms of auditory expertise can help us corroborate (or challenge) the specificity of the advantages previously associated with musical instrument training., Competing Interests: Declaration of Competing Interest None., (Copyright © 2023 The Authors. Published by Elsevier B.V. All rights reserved.)
- Published
- 2024
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29. Implicit auditory memory in older listeners: From encoding to 6-month retention.
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Bianco R, Hall ETR, Pearce MT, and Chait M
- Abstract
Any listening task, from sound recognition to sound-based communication, rests on auditory memory which is known to decline in healthy ageing. However, how this decline maps onto multiple components and stages of auditory memory remains poorly characterised. In an online unsupervised longitudinal study, we tested ageing effects on implicit auditory memory for rapid tone patterns. The test required participants (younger, aged 20-30, and older adults aged 60-70) to quickly respond to rapid regularly repeating patterns emerging from random sequences. Patterns were novel in most trials (REGn), but unbeknownst to the participants, a few distinct patterns reoccurred identically throughout the sessions (REGr). After correcting for processing speed, the response times (RT) to REGn should reflect the information held in echoic and short-term memory before detecting the pattern; long-term memory formation and retention should be reflected by the RT advantage (RTA) to REGr vs REGn which is expected to grow with exposure. Older participants were slower than younger adults in detecting REGn and exhibited a smaller RTA to REGr. Computational simulations using a model of auditory sequence memory indicated that these effects reflect age-related limitations both in early and long-term memory stages. In contrast to ageing-related accelerated forgetting of verbal material, here older adults maintained stable memory traces for REGr patterns up to 6 months after the first exposure. The results demonstrate that ageing is associated with reduced short-term memory and long-term memory formation for tone patterns, but not with forgetting, even over surprisingly long timescales., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 Published by Elsevier B.V.)
- Published
- 2023
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30. Neural dynamics underlying successful auditory short-term memory performance.
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Pomper U, Curetti LZ, and Chait M
- Subjects
- Humans, Auditory Perception physiology, Acoustic Stimulation, Sound, Memory, Short-Term physiology, Auditory Cortex physiology
- Abstract
Listeners often operate in complex acoustic environments, consisting of many concurrent sounds. Accurately encoding and maintaining such auditory objects in short-term memory is crucial for communication and scene analysis. Yet, the neural underpinnings of successful auditory short-term memory (ASTM) performance are currently not well understood. To elucidate this issue, we presented a novel, challenging auditory delayed match-to-sample task while recording MEG. Human participants listened to 'scenes' comprising three concurrent tone pip streams. The task was to indicate, after a delay, whether a probe stream was present in the just-heard scene. We present three key findings: First, behavioural performance revealed faster responses in correct versus incorrect trials as well as in 'probe present' versus 'probe absent' trials, consistent with ASTM search. Second, successful compared with unsuccessful ASTM performance was associated with a significant enhancement of event-related fields and oscillatory activity in the theta, alpha and beta frequency ranges. This extends previous findings of an overall increase of persistent activity during short-term memory performance. Third, using distributed source modelling, we found these effects to be confined mostly to sensory areas during encoding, presumably related to ASTM contents per se. Parietal and frontal sources then became relevant during the maintenance stage, indicating that effective STM operation also relies on ongoing inhibitory processes suppressing task-irrelevant information. In summary, our results deliver a detailed account of the neural patterns that differentiate successful from unsuccessful ASTM performance in the context of a complex, multi-object auditory scene., (© 2023 The Authors. European Journal of Neuroscience published by Federation of European Neuroscience Societies and John Wiley & Sons Ltd.)
- Published
- 2023
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31. Pupil Dilation and Microsaccades Provide Complementary Insights into the Dynamics of Arousal and Instantaneous Attention during Effortful Listening.
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Contadini-Wright C, Magami K, Mehta N, and Chait M
- Subjects
- Male, Female, Humans, Auditory Perception, Noise, Arousal, Pupil, Speech Perception
- Abstract
Listening in noisy environments requires effort- the active engagement of attention and other cognitive abilities- as well as increased arousal. The ability to separately quantify the contribution of these components is key to understanding the dynamics of effort and how it may change across listening situations and in certain populations. We concurrently measured two types of ocular data in young participants (both sexes): pupil dilation (PD; thought to index arousal aspects of effort) and microsaccades (MS; hypothesized to reflect automatic visual exploratory sampling), while they performed a speech-in-noise task under high- (HL) and low- (LL) listening load conditions. Sentences were manipulated so that the behaviorally relevant information (keywords) appeared at the end (Experiment 1) or beginning (Experiment 2) of the sentence, resulting in different temporal demands on focused attention. In line with previous reports, PD effects were associated with increased dilation under load. We observed a sustained difference between HL and LL conditions, consistent with increased phasic and tonic arousal. Importantly we show that MS rate was also modulated by listening load. This was manifested as a reduced MS rate in HL relative to LL. Critically, in contrast to the sustained difference seen for PD, MS effects were localized in time, specifically during periods when demands on auditory attention were greatest. These results demonstrate that auditory selective attention interfaces with the mechanisms controlling MS generation, establishing MS as an informative measure, complementary to PD, with which to quantify the temporal dynamics of auditory attentional processing under effortful listening conditions. SIGNIFICANCE STATEMENT Listening effort, reflecting the "cognitive bandwidth" deployed to effectively process sound in adverse environments, contributes critically to listening success. Understanding listening effort and the processes involved in its allocation is a major challenge in auditory neuroscience. Here, we demonstrate that microsaccade rate can be used to index a specific subcomponent of listening effort, the allocation of instantaneous auditory attention, that is distinct from the modulation of arousal indexed by pupil dilation (currently the dominant measure of listening effort). These results reveal the push-pull process through which auditory attention interfaces with the (visual) attention network that controls microsaccades, establishing microsaccades as a powerful tool for measuring auditory attention and its deficits., (Copyright © 2023 Contadini-Wright et al.)
- Published
- 2023
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32. No Link Between Speech-in-Noise Perception and Auditory Sensory Memory - Evidence From a Large Cohort of Older and Younger Listeners.
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Bianco R and Chait M
- Subjects
- Humans, Aged, Hearing physiology, Noise adverse effects, Memory, Short-Term physiology, Speech physiology, Speech Perception physiology
- Abstract
A growing literature is demonstrating a link between working memory (WM) and speech-in-noise (SiN) perception. However, the nature of this correlation and which components of WM might underlie it, are being debated. We investigated how SiN reception links with auditory sensory memory (aSM) - the low-level processes that support the short-term maintenance of temporally unfolding sounds. A large sample of old ( N = 199, 60-79 yo) and young ( N = 149, 20-35 yo) participants was recruited online and performed a coordinate response measure-based speech-in-babble task that taps listeners' ability to track a speech target in background noise. We used two tasks to investigate implicit and explicit aSM. Both were based on tone patterns overlapping in processing time scales with speech (presentation rate of tones 20 Hz; of patterns 2 Hz). We hypothesised that a link between SiN and aSM may be particularly apparent in older listeners due to age-related reduction in both SiN reception and aSM. We confirmed impaired SiN reception in the older cohort and demonstrated reduced aSM performance in those listeners. However, SiN and aSM did not share variability. Across the two age groups, SiN performance was predicted by a binaural processing test and age. The results suggest that previously observed links between WM and SiN may relate to the executive components and other cognitive demands of the used tasks. This finding helps to constrain the search for the perceptual and cognitive factors that explain individual variability in SiN performance., Competing Interests: Declaration of Conflicting InterestsThe authors declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
- Published
- 2023
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33. Immune and epithelial determinants of age-related risk and alveolar injury in fatal COVID-19.
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Chait M, Yilmaz MM, Shakil S, Ku AW, Dogra P, Connors TJ, Szabo PA, Gray JI, Wells SB, Kubota M, Matsumoto R, Poon MM, Snyder ME, Baldwin MR, Sims PA, Saqi A, Farber DL, and Weisberg SP
- Subjects
- Adolescent, Adult, Aged, Aged, 80 and over, Alveolar Epithelial Cells pathology, Autopsy, Humans, Lung pathology, Middle Aged, Young Adult, Acute Lung Injury pathology, COVID-19
- Abstract
Respiratory failure in COVID-19 is characterized by widespread disruption of the lung's alveolar gas exchange interface. To elucidate determinants of alveolar lung damage, we performed epithelial and immune cell profiling in lungs from 24 COVID-19 autopsies and 43 uninfected organ donors ages 18-92 years. We found marked loss of type 2 alveolar epithelial (T2AE) cells and increased perialveolar lymphocyte cytotoxicity in all fatal COVID-19 cases, even at early stages before typical patterns of acute lung injury are histologically apparent. In lungs from uninfected organ donors, there was also progressive loss of T2AE cells with increasing age, which may increase susceptibility to COVID-19-mediated lung damage in older individuals. In the fatal COVID-19 cases, macrophage infiltration differed according to the histopathological pattern of lung injury. In cases with acute lung injury, we found accumulation of CD4+ macrophages that expressed distinctly high levels of T cell activation and costimulation genes and strongly correlated with increased extent of alveolar epithelial cell depletion and CD8+ T cell cytotoxicity. Together, our results show that T2AE cell deficiency may underlie age-related COVID-19 risk and initiate alveolar dysfunction shortly after infection, and we define immune cell mediators that may contribute to alveolar injury in distinct pathological stages of fatal COVID-19.
- Published
- 2022
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34. An online headphone screening test based on dichotic pitch.
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Milne AE, Bianco R, Poole KC, Zhao S, Oxenham AJ, Billig AJ, and Chait M
- Subjects
- Acoustic Stimulation, Humans, Psychophysics, Sound, Auditory Perception, Noise
- Abstract
Online experimental platforms can be used as an alternative to, or complement, lab-based research. However, when conducting auditory experiments via online methods, the researcher has limited control over the participants' listening environment. We offer a new method to probe one aspect of that environment, headphone use. Headphones not only provide better control of sound presentation but can also "shield" the listener from background noise. Here we present a rapid (< 3 min) headphone screening test based on Huggins Pitch (HP), a perceptual phenomenon that can only be detected when stimuli are presented dichotically. We validate this test using a cohort of "Trusted" online participants who completed the test using both headphones and loudspeakers. The same participants were also used to test an existing headphone test (AP test; Woods et al., 2017, Attention Perception Psychophysics). We demonstrate that compared to the AP test, the HP test has a higher selectivity for headphone users, rendering it as a compelling alternative to existing methods. Overall, the new HP test correctly detects 80% of headphone users and has a false-positive rate of 20%. Moreover, we demonstrate that combining the HP test with an additional test-either the AP test or an alternative based on a beat test (BT)-can lower the false-positive rate to ~ 7%. This should be useful in situations where headphone use is particularly critical (e.g., dichotic or spatial manipulations). Code for implementing the new tests is publicly available in JavaScript and through Gorilla (gorilla.sc)., (© 2020. The Author(s).)
- Published
- 2021
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35. Sustained Pupil Responses Are Modulated by Predictability of Auditory Sequences.
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Milne AE, Zhao S, Tampakaki C, Bury G, and Chait M
- Abstract
The brain is highly sensitive to auditory regularities and exploits the predictable order of sounds in many situations, from parsing complex auditory scenes, to the acquisition of language. To understand the impact of stimulus predictability on perception, it is important to determine how the detection of predictable structure influences processing and attention. Here, we use pupillometry to gain insight into the effect of sensory regularity on arousal. Pupillometry is a commonly used measure of salience and processing effort, with more perceptually salient or perceptually demanding stimuli consistently associated with larger pupil diameters. In two experiments we tracked human listeners' pupil dynamics while they listened to sequences of 50-ms tone pips of different frequencies. The order of the tone pips was either random, contained deterministic (fully predictable) regularities (experiment 1, n = 18, 11 female) or had a probabilistic regularity structure (experiment 2, n = 20, 17 female). The sequences were rapid, preventing conscious tracking of sequence structure thus allowing us to focus on the automatic extraction of different types of regularities. We hypothesized that if regularity facilitates processing by reducing processing demands, a smaller pupil diameter would be seen in response to regular relative to random patterns. Conversely, if regularity is associated with heightened arousal and attention (i.e., engages processing resources) the opposite pattern would be expected. In both experiments we observed a smaller sustained (tonic) pupil diameter for regular compared with random sequences, consistent with the former hypothesis and confirming that predictability facilitates sequence processing. SIGNIFICANCE STATEMENT The brain is highly sensitive to auditory regularities. To appreciate the impact that the presence of predictability has on perception, we need to better understand how a predictable structure influences processing and attention. We recorded listeners' pupil responses to sequences of tones that followed either a predictable or unpredictable pattern, as the pupil can be used to implicitly tap into these different cognitive processes. We found that the pupil showed a smaller sustained diameter to predictable sequences, indicating that predictability eased processing rather than boosted attention. The findings suggest that the pupil response can be used to study the automatic extraction of regularities, and that the effects are most consistent with predictability helping the listener to efficiently process upcoming sounds., (Copyright © 2021 Milne et al.)
- Published
- 2021
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36. Correction: PPM-Decay: A computational model of auditory prediction with memory decay.
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Harrison PMC, Bianco R, Chait M, and Pearce MT
- Abstract
[This corrects the article DOI: 10.1371/journal.pcbi.1008304.].
- Published
- 2021
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37. Longitudinal profiling of respiratory and systemic immune responses reveals myeloid cell-driven lung inflammation in severe COVID-19.
- Author
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Szabo PA, Dogra P, Gray JI, Wells SB, Connors TJ, Weisberg SP, Krupska I, Matsumoto R, Poon MML, Idzikowski E, Morris SE, Pasin C, Yates AJ, Ku A, Chait M, Davis-Porada J, Guo XV, Zhou J, Steinle M, Mackay S, Saqi A, Baldwin MR, Sims PA, and Farber DL
- Subjects
- Adolescent, Adult, Age Factors, Aged, Aged, 80 and over, COVID-19 blood, COVID-19 mortality, COVID-19 pathology, Cytokines immunology, Cytokines metabolism, Humans, Inflammation, Longitudinal Studies, Lung pathology, Macrophages immunology, Macrophages pathology, Middle Aged, Monocytes immunology, Monocytes pathology, Myeloid Cells pathology, SARS-CoV-2, T-Lymphocytes immunology, T-Lymphocytes pathology, Transcriptome, Young Adult, COVID-19 immunology, Lung immunology, Myeloid Cells immunology
- Abstract
Immune response dynamics in coronavirus disease 2019 (COVID-19) and their severe manifestations have largely been studied in circulation. Here, we examined the relationship between immune processes in the respiratory tract and circulation through longitudinal phenotypic, transcriptomic, and cytokine profiling of paired airway and blood samples from patients with severe COVID-19 relative to heathy controls. In COVID-19 airways, T cells exhibited activated, tissue-resident, and protective profiles; higher T cell frequencies correlated with survival and younger age. Myeloid cells in COVID-19 airways featured hyperinflammatory signatures, and higher frequencies of these cells correlated with mortality and older age. In COVID-19 blood, aberrant CD163
+ monocytes predominated over conventional monocytes, and were found in corresponding airway samples and in damaged alveoli. High levels of myeloid chemoattractants in airways suggest recruitment of these cells through a CCL2-CCR2 chemokine axis. Our findings provide insights into immune processes driving COVID-19 lung pathology with therapeutic implications for targeting inflammation in the respiratory tract., Competing Interests: Declaration of interests J.Z., M.S., and S.M. have competing interests with IsoPlexis. The remaining authors declare no competing interests., (Copyright © 2021 Elsevier Inc. All rights reserved.)- Published
- 2021
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38. Corrigendum to "The effect of healthy aging on change detection and sensitivity to predictable structure in crowded acoustic scenes" [Hearing Research, vol. 399, 2021].
- Author
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de Kerangal M, Vickers D, and Chait M
- Published
- 2021
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39. Sensitivity to temporal structure facilitates perceptual analysis of complex auditory scenes.
- Author
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Aman L, Picken S, Andreou LV, and Chait M
- Subjects
- Acoustic Stimulation, Attention, Hearing, Auditory Perception
- Abstract
The notion that sensitivity to the statistical structure of the environment is pivotal to perception has recently garnered considerable attention. Here we investigated this issue in the context of hearing. Building on previous work (Sohoglu and Chait, 2016a; elife), stimuli were artificial 'soundscapes' populated by multiple (up to 14) simultaneous streams ('auditory objects') comprised of tone-pip sequences, each with a distinct frequency and pattern of amplitude modulation. Sequences were either temporally regular or random. We show that listeners' ability to detect abrupt appearance or disappearance of a stream is facilitated when scene streams were characterized by a temporally regular fluctuation pattern. The regularity of the changing stream as well as that of the background (non-changing) streams contribute independently to this effect. Remarkably, listeners benefit from regularity even when they are not consciously aware of it. These findings establish that perception of complex acoustic scenes relies on the availability of detailed representations of the regularities automatically extracted from multiple concurrent streams., (Copyright © 2020. Published by Elsevier B.V.)
- Published
- 2021
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40. Distinct antibody responses to SARS-CoV-2 in children and adults across the COVID-19 clinical spectrum.
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Weisberg SP, Connors TJ, Zhu Y, Baldwin MR, Lin WH, Wontakal S, Szabo PA, Wells SB, Dogra P, Gray J, Idzikowski E, Stelitano D, Bovier FT, Davis-Porada J, Matsumoto R, Poon MML, Chait M, Mathieu C, Horvat B, Decimo D, Hudson KE, Zotti FD, Bitan ZC, La Carpia F, Ferrara SA, Mace E, Milner J, Moscona A, Hod E, Porotto M, and Farber DL
- Subjects
- Adolescent, Adult, Aged, COVID-19 virology, Child, Child, Preschool, Female, Humans, Immunoglobulin A immunology, Immunoglobulin G immunology, Immunoglobulin M immunology, Male, Middle Aged, SARS-CoV-2 physiology, Young Adult, Antibodies, Viral immunology, Antibody Formation immunology, COVID-19 immunology, Nucleocapsid Proteins immunology, SARS-CoV-2 immunology, Spike Glycoprotein, Coronavirus immunology
- Abstract
Clinical manifestations of COVID-19 caused by the new coronavirus SARS-CoV-2 are associated with age
1,2 . Adults develop respiratory symptoms, which can progress to acute respiratory distress syndrome (ARDS) in the most severe form, while children are largely spared from respiratory illness but can develop a life-threatening multisystem inflammatory syndrome (MIS-C)3-5 . Here, we show distinct antibody responses in children and adults after SARS-CoV-2 infection. Adult COVID-19 cohorts had anti-spike (S) IgG, IgM and IgA antibodies, as well as anti-nucleocapsid (N) IgG antibody, while children with and without MIS-C had reduced breadth of anti-SARS-CoV-2-specific antibodies, predominantly generating IgG antibodies specific for the S protein but not the N protein. Moreover, children with and without MIS-C had reduced neutralizing activity as compared to both adult COVID-19 cohorts, indicating a reduced protective serological response. These results suggest a distinct infection course and immune response in children independent of whether they develop MIS-C, with implications for developing age-targeted strategies for testing and protecting the population.- Published
- 2021
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41. Reward Enhances Online Participants' Engagement With a Demanding Auditory Task.
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Bianco R, Mills G, de Kerangal M, Rosen S, and Chait M
- Subjects
- Auditory Perception, Auditory Threshold, Humans, Noise, Reward, Speech Perception
- Abstract
Online recruitment platforms are increasingly used for experimental research. Crowdsourcing is associated with numerous benefits but also notable constraints, including lack of control over participants' environment and engagement. In the context of auditory experiments, these limitations may be particularly detrimental to threshold-based tasks that require effortful listening. Here, we ask whether incorporating a performance-based monetary bonus improves speech reception performance of online participants. In two experiments, participants performed an adaptive matrix-type speech-in-noise task (where listeners select two key words out of closed sets). In Experiment 1, our results revealed worse performance in online ( N = 49) compared with in-lab ( N = 81) groups. Specifically, relative to the in-lab cohort, significantly fewer participants in the online group achieved very low thresholds. In Experiment 2 ( N = 200), we show that a monetary reward improved listeners' thresholds to levels similar to those observed in the lab setting. Overall, the results suggest that providing a small performance-based bonus increases participants' task engagement, facilitating a more accurate estimation of auditory ability under challenging listening conditions.
- Published
- 2021
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42. The effect of healthy aging on change detection and sensitivity to predictable structure in crowded acoustic scenes.
- Author
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de Kerangal M, Vickers D, and Chait M
- Subjects
- Acoustic Stimulation, Acoustics, Adult, Aged, Aged, 80 and over, Auditory Perception, Hearing, Humans, Middle Aged, Young Adult, Healthy Aging
- Abstract
The auditory system plays a critical role in supporting our ability to detect abrupt changes in our surroundings. Here we study how this capacity is affected in the course of healthy ageing. Artifical acoustic 'scenes', populated by multiple concurrent streams of pure tones ('sources') were used to capture the challenges of listening in complex acoustic environments. Two scene conditions were included: REG scenes consisted of sources characterized by a regular temporal structure. Matched RAND scenes contained sources which were temporally random. Changes, manifested as the abrupt disappearance of one of the sources, were introduced to a subset of the trials and participants ('young' group N = 41, age 20-38 years; 'older' group N = 41, age 60-82 years) were instructed to monitor the scenes for these events. Previous work demonstrated that young listeners exhibit better change detection performance in REG scenes, reflecting sensitivity to temporal structure. Here we sought to determine: (1) Whether 'baseline' change detection ability (i.e. in RAND scenes) is affected by age. (2) Whether aging affects listeners' sensitivity to temporal regularity. (3) How change detection capacity relates to listeners' hearing and cognitive profile (a battery of tests that capture hearing and cognitive abilities hypothesized to be affected by aging). The results demonstrated that healthy aging is associated with reduced sensitivity to abrupt scene changes in RAND scenes but that performance does not correlate with age or standard audiological measures such as pure tone audiometry or speech in noise performance. Remarkably older listeners' change detection performance improved substantially (up to the level exhibited by young listeners) in REG relative to RAND scenes. This suggests that the ability to extract and track the regularity associated with scene sources, even in crowded acoustic environments, is relatively preserved in older listeners., (Copyright © 2020 Elsevier B.V. All rights reserved.)
- Published
- 2021
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43. PPM-Decay: A computational model of auditory prediction with memory decay.
- Author
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Harrison PMC, Bianco R, Chait M, and Pearce MT
- Subjects
- Algorithms, Humans, Music, Auditory Perception, Computer Simulation, Memory
- Abstract
Statistical learning and probabilistic prediction are fundamental processes in auditory cognition. A prominent computational model of these processes is Prediction by Partial Matching (PPM), a variable-order Markov model that learns by internalizing n-grams from training sequences. However, PPM has limitations as a cognitive model: in particular, it has a perfect memory that weights all historic observations equally, which is inconsistent with memory capacity constraints and recency effects observed in human cognition. We address these limitations with PPM-Decay, a new variant of PPM that introduces a customizable memory decay kernel. In three studies-one with artificially generated sequences, one with chord sequences from Western music, and one with new behavioral data from an auditory pattern detection experiment-we show how this decay kernel improves the model's predictive performance for sequences whose underlying statistics change over time, and enables the model to capture effects of memory constraints on auditory pattern detection. The resulting model is available in our new open-source R package, ppm (https://github.com/pmcharrison/ppm)., Competing Interests: The authors have declared that no competing interests exist.
- Published
- 2020
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44. Tegoprazan to treat gastroesophageal reflux disease.
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Mermelstein J, Mermelstein AC, and Chait MM
- Subjects
- Humans, Proton Pump Inhibitors therapeutic use, Republic of Korea, Benzene Derivatives pharmacology, Gastroesophageal Reflux drug therapy, Imidazoles pharmacology
- Abstract
Gastroesophageal reflux disease (GERD) is the most common upper gastrointestinal disorder in the United States. Although proton pump inhibitors (PPIs) are the mainstay of therapy for GERD and its complications, they have several limitations, including incomplete symptom resolution. Potassium-competitive acid blockers (P-CABs) were developed to address the limitations of PPIs as well as the need for improved antisecretory effects. Tegoprazan, the newest P-CAB, was approved in 2018 in South Korea for the treatment of erosive esophagitis (EE) and nonerosive reflux disease (NERD). A highly selective inhibitor of the H+/K+-ATPase, tegoprazan is also safe and effective for nocturnal acid breakthrough (NAB) and motility. Further studies of tegoprazan are warranted to define its potential role in the treatment of acid-related disorders., (Copyright 2020 Clarivate Analytics.)
- Published
- 2020
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45. Analysis of respiratory and systemic immune responses in COVID-19 reveals mechanisms of disease pathogenesis.
- Author
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Szabo PA, Dogra P, Gray JI, Wells SB, Connors TJ, Weisberg SP, Krupska I, Matsumoto R, Poon MML, Idzikowski E, Morris SE, Pasin C, Yates AJ, Ku A, Chait M, Davis-Porada J, Zhou J, Steinle M, Mackay S, Saqi A, Baldwin M, Sims PA, and Farber DL
- Abstract
Immune responses to respiratory viruses like SARS-CoV-2 originate and function in the lung, yet assessments of human immunity are often limited to blood. Here, we conducted longitudinal, high-dimensional profiling of paired airway and blood samples from patients with severe COVID-19, revealing immune processes in the respiratory tract linked to disease pathogenesis. Survival from severe disease was associated with increased CD4
+ T cells and decreased monocyte/macrophage frequencies in the airway, but not in blood. Airway T cells and macrophages exhibited tissue-resident phenotypes and activation signatures, including high level expression and secretion of monocyte chemoattractants CCL2 and CCL3 by airway macrophages. By contrast, monocytes in blood expressed the CCL2-receptor CCR2 and aberrant CD163+ and immature phenotypes. Extensive accumulation of CD163+ monocyte/macrophages within alveolar spaces in COVID-19 lung autopsies suggested recruitment from circulation. Our findings provide evidence that COVID-19 pathogenesis is driven by respiratory immunity, and rationale for site-specific treatment and prevention strategies.- Published
- 2020
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46. Erector spinae plane block with catheter for management of percutaneous nephrolithotomy: A three case report.
- Author
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Resnick A, Chait M, Landau S, and Krishnan S
- Subjects
- Aged, Anesthetics, Local therapeutic use, Bupivacaine therapeutic use, Dexamethasone therapeutic use, Female, Humans, Middle Aged, Paraspinal Muscles, Kidney Calculi surgery, Nephrolithotomy, Percutaneous methods, Nerve Block methods, Pain, Postoperative prevention & control
- Abstract
Introduction: Percutaneous nephrolithotomy is a procedure used for management of refractory renal calculi. Oral and parenteral opioids, along with local anesthetic infiltration, neuraxial anesthesia, and paravertebral blocks are the most common methods of managing intra-operative and post-operative pain for these patients. The erector spinae plane block with catheter (ESPC) is a newer interfascial regional anesthetic technique that can be used to manage peri-operative pain in these patients., Clinical Findings: Three patients complained of significant flank pain were scheduled for percutaneous nephrolithotomy under general anesthesia in the prone position., Diagnoses: Patients were diagnosed with large renal calculi., Therapeutic Interventions: Patients received ESPC in the pre-operative holding area at the level of the T7 transverse process. The ESPCS were bolused with a solution of 30 mL 0.25% bupivacaine with 4 mg dexamethasone prior to surgery. Patients also received oral tramadol 50 mg and acetaminophen 1 g as part of the multimodal pain protocol prior to surgery. After the procedure, the patients were bolused with 0.25% bupivacaine or started on an infusion of 0.25% bupivacaine to manage their pain., Outcomes: No opioid or other pain medications, other than the local anesthetic solution given in the ESPCs, were used during the intra-operative or post-operative period for management of pain in these patients. Visual analogue scale (VAS) scores were below 4 for all patients in the post-operative period, and patients did not report any issues with post-operative nausea or vomiting., Conclusion: These patients were compared to 3 prior patients who had undergone percutaneous nephrolithotomy without ESPC. The 3 patients without ESPC placement reported increased VAS scores, had increased opioid/pain medication consumption intraoperatively and postoperatively, and had increased incidence of perioperative nausea when compared to our ESPC patients. Our report shows that ESPC, in combination with a multimodal pain protocol, can be a good option for management of patients undergoing percutaneous nephrolithotomy.
- Published
- 2020
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47. Multivoxel codes for representing and integrating acoustic features in human cortex.
- Author
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Sohoglu E, Kumar S, Chait M, and Griffiths TD
- Subjects
- Acoustic Stimulation, Adolescent, Adult, Algorithms, Brain Mapping, Cluster Analysis, Female, Functional Laterality physiology, Humans, Magnetic Resonance Imaging, Male, Multivariate Analysis, Noise, Parietal Lobe diagnostic imaging, Parietal Lobe physiology, Young Adult, Auditory Cortex diagnostic imaging, Auditory Cortex physiology, Auditory Perception physiology
- Abstract
Using fMRI and multivariate pattern analysis, we determined whether spectral and temporal acoustic features are represented by independent or integrated multivoxel codes in human cortex. Listeners heard band-pass noise varying in frequency (spectral) and amplitude-modulation (AM) rate (temporal) features. In the superior temporal plane, changes in multivoxel activity due to frequency were largely invariant with respect to AM rate (and vice versa), consistent with an independent representation. In contrast, in posterior parietal cortex, multivoxel representation was exclusively integrated and tuned to specific conjunctions of frequency and AM features (albeit weakly). Direct between-region comparisons show that whereas independent coding of frequency weakened with increasing levels of the hierarchy, such a progression for AM and integrated coding was less fine-grained and only evident in the higher hierarchical levels from non-core to parietal cortex (with AM coding weakening and integrated coding strengthening). Our findings support the notion that primary auditory cortex can represent spectral and temporal acoustic features in an independent fashion and suggest a role for parietal cortex in feature integration and the structuring of sensory input., (Copyright © 2020 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2020
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48. Spatial cues can support auditory figure-ground segregation.
- Author
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Reed DK, Chait M, Tóth B, Winkler I, and Shinn-Cunningham B
- Subjects
- Acoustic Stimulation, Auditory Perception, Humans, Sound, Cues, Sound Localization
- Abstract
A study by Tóth, Kocsis, Háden, Szerafin, Shinn-Cunningham, and Winkler [Neuroimage 141, 108 - 119 (2016)] reported that spatial cues (such as interaural differences or ITDs) that differentiate the perceived sound source directions of a target tone sequence (figure) from simultaneous distracting tones (background) did not improve the ability of participants to detect the target sequence. The present study aims to investigate more systematically whether spatially separating a complex auditory "figure" from the background auditory stream may enhance the detection of a target in a cluttered auditory scene. Results of the presented experiment suggest that the previous negative results arose because of the specific experimental conditions tested. Here the authors find that ITDs provide a clear benefit for detecting a target tone sequence amid a mixture of other simultaneous tone bursts.
- Published
- 2020
- Full Text
- View/download PDF
49. Long-term implicit memory for sequential auditory patterns in humans.
- Author
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Bianco R, Harrison PM, Hu M, Bolger C, Picken S, Pearce MT, and Chait M
- Subjects
- Adult, Female, Humans, Male, Memory and Learning Tests, Reaction Time physiology, Young Adult, Acoustic Stimulation methods, Auditory Perception physiology, Memory, Long-Term physiology
- Abstract
Memory, on multiple timescales, is critical to our ability to discover the structure of our surroundings, and efficiently interact with the environment. We combined behavioural manipulation and modelling to investigate the dynamics of memory formation for rarely reoccurring acoustic patterns. In a series of experiments, participants detected the emergence of regularly repeating patterns within rapid tone-pip sequences. Unbeknownst to them, a few patterns reoccurred every ~3 min. All sequences consisted of the same 20 frequencies and were distinguishable only by the order of tone-pips. Despite this, reoccurring patterns were associated with a rapidly growing detection-time advantage over novel patterns. This effect was implicit, robust to interference, and persisted for 7 weeks. The results implicate an interplay between short (a few seconds) and long-term (over many minutes) integration in memory formation and demonstrate the remarkable sensitivity of the human auditory system to sporadically reoccurring structure within the acoustic environment., Competing Interests: RB, PH, MH, CB, SP, MP, MC No competing interests declared, (© 2020, Bianco et al.)
- Published
- 2020
- Full Text
- View/download PDF
50. Tissue-Resident Memory T Cells Mediate Immune Homeostasis in the Human Pancreas through the PD-1/PD-L1 Pathway.
- Author
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Weisberg SP, Carpenter DJ, Chait M, Dogra P, Gartrell-Corrado RD, Chen AX, Campbell S, Liu W, Saraf P, Snyder ME, Kubota M, Danzl NM, Schrope BA, Rabadan R, Saenger Y, Chen X, and Farber DL
- Subjects
- B7-H1 Antigen genetics, CD58 Antigens metabolism, Humans, Immunity, Mucosal genetics, Immunity, Mucosal physiology, Immunologic Memory genetics, Macrophages immunology, Macrophages metabolism, Pancreas immunology, Pancreas pathology, Pancreatitis genetics, Programmed Cell Death 1 Receptor genetics, Signal Transduction, T-Lymphocyte Subsets immunology, B7-H1 Antigen metabolism, Immunologic Memory physiology, Pancreas metabolism, Pancreatitis immunology, Pancreatitis metabolism, Programmed Cell Death 1 Receptor metabolism, T-Lymphocyte Subsets metabolism
- Abstract
Non-recirculating tissue-resident memory T cells (TRMs) are the predominant T cell subset in diverse tissue sites, where they mediate protective immune responses in situ. Here, we reveal a role for TRM in maintaining immune homeostasis in the human pancreas through interactions with resident macrophages and the PD-1/PD-L1 inhibitory pathway. Using tissues obtained from organ donors, we identify that pancreas T cells comprise CD8
+ PD-1hi TRMs, which are phenotypically, functionally, and transcriptionally distinct compared to TRMs in neighboring jejunum and lymph node sites. Pancreas TRMs cluster with resident macrophages throughout the exocrine areas; TRM effector functions are enhanced by macrophage-derived co-stimulation and attenuated by the PD-1/PD-L1 pathways. Conversely, in samples from chronic pancreatitis, TRMs exhibit reduced PD-1 expression and reduced interactions with macrophages. These findings suggest important roles for PD-1 and TRM-macrophage interactions in controlling tissue homeostasis and immune dysfunctions underlying inflammatory disease, with important implications for PD-1-based immunotherapies., (Copyright © 2019 The Author(s). Published by Elsevier Inc. All rights reserved.)- Published
- 2019
- Full Text
- View/download PDF
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