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Cook H, Bezsudnova Y, Koponen LM, Jensen O, Barontini G, Kowalczyk AU. An optically pumped magnetic gradiometer for the detection of human biomagnetism. Quantum Sci Technol 2024; 9:035016. [PMID: 38680502 PMCID: PMC11047143 DOI: 10.1088/2058-9565/ad3d81] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 02/09/2024] [Revised: 03/21/2024] [Accepted: 04/11/2024] [Indexed: 05/01/2024]
Abstract
We realise an intrinsic optically pumped magnetic gradiometer based on non-linear magneto-optical rotation. We show that our sensor can reach a gradiometric sensitivity of 18 fT cm - 1 Hz - 1 and can reject common mode homogeneous magnetic field noise with up to 30 dB attenuation. We demonstrate that our magnetic field gradiometer is sufficiently sensitive and resilient to be employed in biomagnetic applications. In particular, we are able to record the auditory evoked response of the human brain, and to perform real-time magnetocardiography in the presence of external magnetic field disturbances. Our gradiometer provides complementary capabilities in human biomagnetic sensing to optically pumped magnetometers, and opens new avenues in the detection of human biomagnetism.
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Affiliation(s)
- Harry Cook
- School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Yulia Bezsudnova
- School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
| | - Lari M Koponen
- Centre for Human Brain Health, School of Psychology, University of Birmingham, Edgbaston, Birmingham B15 2SA, United Kingdom
| | - Ole Jensen
- Centre for Human Brain Health, School of Psychology, University of Birmingham, Edgbaston, Birmingham B15 2SA, United Kingdom
| | - Giovanni Barontini
- School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT, United Kingdom
- Centre for Human Brain Health, School of Psychology, University of Birmingham, Edgbaston, Birmingham B15 2SA, United Kingdom
| | - Anna U Kowalczyk
- Centre for Human Brain Health, School of Psychology, University of Birmingham, Edgbaston, Birmingham B15 2SA, United Kingdom
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Soeta Y, Onogawa E. Physiological evaluations of low-level impulsive sounds generated by an air conditioner. Front Psychol 2023; 14:1128752. [PMID: 36844263 PMCID: PMC9950742 DOI: 10.3389/fpsyg.2023.1128752] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Accepted: 01/25/2023] [Indexed: 02/12/2023] Open
Abstract
Air conditioners are typically installed in buildings and vehicles to control thermal conditions for long periods of time. Air conditioners generate certain types of sounds while functioning, which are among the main noise sources in buildings and vehicles. Most sounds produced by the air conditioner do not change with time, and the sound quality of steady sounds has been investigated. However, air conditioners can generate low-level impulsive sounds. Customers complain of the discomfort caused when these sounds disturb the silence in their living rooms and bedrooms. This study aimed to determine the physical factors that have a significant effect on physiological responses to low-level impulsive sounds produced by air conditioners. We used physiological responses because it is difficult for people to evaluate sounds psychologically when they are sleeping or are not focused on the sounds. The A-weighted equivalent continuous sound pressure level (LAeq) and the factors extracted from the autocorrelation function (ACF) were evaluated as physical factors. Participant responses on electroencephalography (EEG) were evaluated. The correlation between the EEG responses and ACF factors was determined. The LAeq, peak, and delay time to the first maximum peak of the ACF were identified as significant factors for physiological responses to low-level impulsive sounds.
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Affiliation(s)
- Yoshiharu Soeta
- Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST), Osaka, Japan,*Correspondence: Yoshiharu Soeta, ✉
| | - Ei Onogawa
- Research and Innovation Center, Mitsubishi Heavy Industries Ltd., Nagoya, Aichi, Japan
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Norcia AM, Lee A, Meredith WJ, Kohler PJ, Pei F, Ghassan SA, Libove RA, Phillips JM, Hardan AY. A case-control study of visual, auditory and audio-visual sensory interactions in children with autism spectrum disorder. J Vis 2021; 21:5. [PMID: 33830169 PMCID: PMC8039569 DOI: 10.1167/jov.21.4.5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Accepted: 11/09/2020] [Indexed: 01/23/2023] Open
Abstract
To assess the relative integrity of early visual and auditory processes in autism spectrum disorder (ASD), we used frequency-tagged visual and auditory stimulation and high-density electroencephalogram recordings of unimodal and dual-modality responses in a case-control design. To test for the specificity of effects on ASD, we recorded from a smaller group of children with attention-deficit hyperactivity disorder (ADHD). Horizontal 3 cycle per degree (cpd) gratings were presented at 5 Hz, and a random stream of /ba/, /da/, /ga/ syllables was presented at 6 Hz. Grating contrast response functions were measured unimodally and in the presence of a 64-dB auditory input. Auditory response functions were measured unimodally and in the presence of a 40% contrast grating. Children with ASD (n = 34) and ADHD (n = 13) showed a common lack of audio-visual interaction compared to typically developing children (n = 40) when measured at the first harmonic of the visual stimulus frequency. Both patient groups also showed depressed first harmonic responses at low contrast, but the ADHD group had consistently higher first-harmonic responses at high contrast. Children with ASD had a preferential loss of second-harmonic (transient) responses. The alteredtransient responses in ASD are likely to arise very early in the visual pathway and could thus have downstream consequences for many other visual mechanisms and processes. The alteration in audio-visual interaction could be a signature of a comorbid phenotype shared by ASD and ADHD, possibly due to alterations in attentional selection systems.
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Affiliation(s)
- Anthony M Norcia
- Department of Psychology, Stanford University, Stanford, CA, USA
| | - Azalea Lee
- Department of Psychology, Stanford University, Stanford, CA, USA
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
| | | | - Peter J Kohler
- Department of Psychology, York University, Toronto, ON, Canada
- Centre for Vision Research, York University, Toronto, ON, Canada
| | - Francesca Pei
- Department of Psychology, Stanford University, Stanford, CA, USA
| | - Stephanie A Ghassan
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
| | - Robin A Libove
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
| | - Jennifer M Phillips
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
| | - Antonio Y Hardan
- Department of Psychiatry and Behavioral Sciences, Stanford University, Stanford, CA, USA
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Eswaran H, Lau C, Murphy P, Siegel ER, Preissl H, Lowery C. Tracking evoked responses to auditory and visual stimuli in fetuses exposed to maternal high-risk conditions. Dev Psychobiol 2020; 63:5-15. [PMID: 32654120 DOI: 10.1002/dev.22008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2019] [Revised: 04/08/2020] [Accepted: 06/01/2020] [Indexed: 11/05/2022]
Abstract
Magnetoencephalography (MEG) has been successfully applied to record fetal auditory (auditory evoked response [AER]) and visual evoked responses (VER). In this study, we report the AER and VER development trajectory by tracking the evoked response detectability and latency from recordings starting at 27 weeks of gestation in pregnancies classified as high risk. Fetal MEG and ultrasound recordings were performed on 158 pregnant women, and the total number of fetal auditory and visual tests conducted was 321 and 237, respectively. The overall evoked response analysis showed 237 AER (73.8%) and 164 VER detections (69.2%). The mean AER latency was 290.7 (SD 125.5) ms and the mean VER latency was 293.7 (SD 114.5) ms. The rate of decrease (95% confidence limits) in average AER and VER first-peak latency between 100-350 ms was 1.97 (-1.86, +5.81) ms/week and 1.35 (-3.83, +6.53) ms/week, respectively. This trend in high-risk fetuses conforms to the general trajectory of decrease in latency with gestational age progression, even though this decrease was non-significant, as reported in the case of normal growing fetuses. Although there was a significant difference in detection rates between male and female fetuses, this was not reflected in either latency values or the sensory modality applied. Furthermore, the main factors that had the most significant effect on response detectability included the presence of intervening layers of adipose tissue between the fetal head and stimulus source and an increase in the maternal body mass index.
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Affiliation(s)
- Hari Eswaran
- Department of Obstetrics and Gynecology, SARA Fetal MEG Research Center, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Chrystal Lau
- Department of Obstetrics and Gynecology, SARA Fetal MEG Research Center, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Pam Murphy
- Department of Obstetrics and Gynecology, SARA Fetal MEG Research Center, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Eric R Siegel
- Department of Biostatistics, University of Arkansas for Medical Sciences, Little Rock, AR, USA
| | - Hubert Preissl
- Institute for Diabetes Research and Metabolic Diseases (IDM) of the Helmholtz Center Munich at the University of Tübingen, Tübingen, Germany
| | - Curtis Lowery
- Department of Obstetrics and Gynecology, SARA Fetal MEG Research Center, University of Arkansas for Medical Sciences, Little Rock, AR, USA
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Peixe BP, Silva DDD, Biaggio EPV, Bruno RS, Sanguebuche TR, Garcia MV. Applicability of Evoked Auditory Brainstem Responses with Complex Stimuli in Adults with Hearing Loss. Int Arch Otorhinolaryngol 2018; 22:239-244. [PMID: 29983761 PMCID: PMC6033595 DOI: 10.1055/s-0037-1605341] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 06/06/2017] [Indexed: 11/29/2022] Open
Abstract
Introduction The use of the speech-evoked auditory brainstem response (ABR) shows how the brainstem operates up to the subcortex in a more complex manner than when the click-evoked ABR is used. Objective To study the applicability of the speech-evoked ABR in adults with hearing loss. Methods The sample was composed of a study group of 11 subjects, with ages ranging between 18 and 59 years, and auditory thresholds within normal standards, with loss of up to 65 dB at high frequencies or up to moderately severe symmetric sensorineural hearing loss. The sample underwent a basic audiological assessment, as well as speech-evoked ABR and click-evoked ABR, in which waves I, III and V, and V, A, C, D, E, F were respectively marked. The electrophysiological assessments were performed using the SmartEP device (Intelligent Hearing Systems, Miami, FL, US). Results For the speech-evoked ABR, the reference values were used in the identification and analysis of the study group. Those values found for the study group were: V = 8.56; A = 10.97; C = 21.33; D = 29.51; E = 37.93; F = 46.96; and O = 55.97. In the comparison between groups, the study group presented an increase in latency only in wave C. Conclusion The speech-evoked ABR can be performed in subjects with up to moderately severe hearing loss, and the test proved to be appropriate, because, unlike the click-evoked ABR, the former does not suffer influence of peripheral hearing loss.
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Affiliation(s)
- Bruna Pias Peixe
- Department of Speech Theraqpy, Universidade Federal de Santa Maria, Rio Grande do Sul, RS, Brazil
| | - Débora Durigon da Silva
- Department of Speech Theraqpy, Universidade Federal de Santa Maria, Rio Grande do Sul, RS, Brazil
| | | | - Rúbia Soares Bruno
- Department of Speech Theraqpy, Universidade Federal de Santa Maria, Rio Grande do Sul, RS, Brazil
| | | | - Michele Vargas Garcia
- Department of Speech Theraqpy, Universidade Federal de Santa Maria, Rio Grande do Sul, RS, Brazil
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Callan DE, Durantin G, Terzibas C. Classification of single-trial auditory events using dry-wireless EEG during real and motion simulated flight. Front Syst Neurosci 2015; 9:11. [PMID: 25741249 PMCID: PMC4330719 DOI: 10.3389/fnsys.2015.00011] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Accepted: 01/23/2015] [Indexed: 11/13/2022] Open
Abstract
Application of neuro-augmentation technology based on dry-wireless EEG may be considerably beneficial for aviation and space operations because of the inherent dangers involved. In this study we evaluate classification performance of perceptual events using a dry-wireless EEG system during motion platform based flight simulation and actual flight in an open cockpit biplane to determine if the system can be used in the presence of considerable environmental and physiological artifacts. A passive task involving 200 random auditory presentations of a chirp sound was used for evaluation. The advantage of this auditory task is that it does not interfere with the perceptual motor processes involved with piloting the plane. Classification was based on identifying the presentation of a chirp sound vs. silent periods. Evaluation of Independent component analysis (ICA) and Kalman filtering to enhance classification performance by extracting brain activity related to the auditory event from other non-task related brain activity and artifacts was assessed. The results of permutation testing revealed that single trial classification of presence or absence of an auditory event was significantly above chance for all conditions on a novel test set. The best performance could be achieved with both ICA and Kalman filtering relative to no processing: Platform Off (83.4% vs. 78.3%), Platform On (73.1% vs. 71.6%), Biplane Engine Off (81.1% vs. 77.4%), and Biplane Engine On (79.2% vs. 66.1%). This experiment demonstrates that dry-wireless EEG can be used in environments with considerable vibration, wind, acoustic noise, and physiological artifacts and achieve good single trial classification performance that is necessary for future successful application of neuro-augmentation technology based on brain-machine interfaces.
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Affiliation(s)
- Daniel E Callan
- Center for Information and Neural Networks (CiNet), National Institute of Information and Communications Technology (NICT), Osaka University Osaka, Japan ; Multisensory Cognition and Computation Laboratory Universal Communication Research Institute, National Institute of Information and Communications Technology Kyoto, Japan
| | - Gautier Durantin
- Centre Aéronautique et Spatial, Institut Supérieur de l'Aéronautique et de l'Espace, Université de Toulouse Toulouse, France
| | - Cengiz Terzibas
- Multisensory Cognition and Computation Laboratory Universal Communication Research Institute, National Institute of Information and Communications Technology Kyoto, Japan
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Fujioka T, Fidali BC, Ross B. Neural correlates of intentional switching from ternary to binary meter in a musical hemiola pattern. Front Psychol 2014; 5:1257. [PMID: 25429274 PMCID: PMC4228837 DOI: 10.3389/fpsyg.2014.01257] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Accepted: 10/16/2014] [Indexed: 12/02/2022] Open
Abstract
Musical rhythms are often perceived and interpreted within a metrical framework that integrates timing information hierarchically based on interval ratios. Endogenous timing processes facilitate this metrical integration and allow us using the sensory context for predicting when an expected sensory event will happen (“predictive timing”). Previously, we showed that listening to metronomes and subjectively imagining the two different meters of march and waltz modulated the resulting auditory evoked responses in the temporal lobe and motor-related brain areas such as the motor cortex, basal ganglia, and cerebellum. Here we further explored the intentional transitions between the two metrical contexts, known as hemiola in the Western classical music dating back to the sixteenth century. We examined MEG from 12 musicians while they repeatedly listened to a sequence of 12 unaccented clicks with an interval of 390 ms, and tapped to them with the right hand according to a 3 + 3 + 2 + 2 + 2 hemiola accent pattern. While participants listened to the same metronome sequence and imagined the accents, their pattern of brain responses significantly changed just before the “pivot” point of metric transition from ternary to binary meter. Until 100 ms before the pivot point, brain activities were more similar to those in the simple ternary meter than those in the simple binary meter, but the pattern was reversed afterwards. A similar transition was also observed at the downbeat after the pivot. Brain areas related to the metric transition were identified from source reconstruction of the MEG using a beamformer and included auditory cortices, sensorimotor and premotor cortices, cerebellum, inferior/middle frontal gyrus, parahippocampal gyrus, inferior parietal lobule, cingulate cortex, and precuneus. The results strongly support that predictive timing processes related to auditory-motor, fronto-parietal, and medial limbic systems underlie metrical representation and its transitions.
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Affiliation(s)
- Takako Fujioka
- Rotman Research Institute, Baycrest Centre Toronto, ON, Canada ; Center for Computer Research in Music and Acoustics, Department of Music, Stanford University Stanford, CA, USA
| | - Brian C Fidali
- Rotman Research Institute, Baycrest Centre Toronto, ON, Canada ; Brain and Mind Research Institute, Weill Cornell Medical College New York, NY, USA
| | - Bernhard Ross
- Rotman Research Institute, Baycrest Centre Toronto, ON, Canada ; Department of Medical Biophysics, University of Toronto Toronto, ON, Canada
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Raz A, Grady SM, Krause BM, Uhlrich DJ, Manning KA, Banks MI. Preferential effect of isoflurane on top-down vs. bottom-up pathways in sensory cortex. Front Syst Neurosci 2014; 8:191. [PMID: 25339873 PMCID: PMC4188029 DOI: 10.3389/fnsys.2014.00191] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 09/18/2014] [Indexed: 12/31/2022] Open
Abstract
The mechanism of loss of consciousness (LOC) under anesthesia is unknown. Because consciousness depends on activity in the cortico-thalamic network, anesthetic actions on this network are likely critical for LOC. Competing theories stress the importance of anesthetic actions on bottom-up “core” thalamo-cortical (TC) vs. top-down cortico-cortical (CC) and matrix TC connections. We tested these models using laminar recordings in rat auditory cortex in vivo and murine brain slices. We selectively activated bottom-up vs. top-down afferent pathways using sensory stimuli in vivo and electrical stimulation in brain slices, and compared effects of isoflurane on responses evoked via the two pathways. Auditory stimuli in vivo and core TC afferent stimulation in brain slices evoked short latency current sinks in middle layers, consistent with activation of core TC afferents. By contrast, visual stimuli in vivo and stimulation of CC and matrix TC afferents in brain slices evoked responses mainly in superficial and deep layers, consistent with projection patterns of top-down afferents that carry visual information to auditory cortex. Responses to auditory stimuli in vivo and core TC afferents in brain slices were significantly less affected by isoflurane compared to responses triggered by visual stimuli in vivo and CC/matrix TC afferents in slices. At a just-hypnotic dose in vivo, auditory responses were enhanced by isoflurane, whereas visual responses were dramatically reduced. At a comparable concentration in slices, isoflurane suppressed both core TC and CC/matrix TC responses, but the effect on the latter responses was far greater than on core TC responses, indicating that at least part of the differential effects observed in vivo were due to local actions of isoflurane in auditory cortex. These data support a model in which disruption of top-down connectivity contributes to anesthesia-induced LOC, and have implications for understanding the neural basis of consciousness.
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Affiliation(s)
- Aeyal Raz
- Department of Anesthesiology, School of Medicine and Public Health, University of Wisconsin Madison, WI, USA ; Department of Anesthesiology, Rabin Medical Center, Petah-Tikva, Israel, Affiliated with Sackler School of Medicine, Tel Aviv University Tel Aviv, Israel
| | - Sean M Grady
- Department of Anesthesiology, School of Medicine and Public Health, University of Wisconsin Madison, WI, USA
| | - Bryan M Krause
- Neuroscience Training Program, University of Wisconsin Madison, WI, USA
| | - Daniel J Uhlrich
- Department of Neuroscience, University of Wisconsin Madison, WI, USA
| | - Karen A Manning
- Department of Neuroscience, University of Wisconsin Madison, WI, USA
| | - Matthew I Banks
- Department of Anesthesiology, School of Medicine and Public Health, University of Wisconsin Madison, WI, USA ; Department of Neuroscience, University of Wisconsin Madison, WI, USA
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Rong F, Holroyd T, Husain FT, Contreras-Vidal JL, Horwitz B. Task-specific modulation of human auditory evoked response in a delayed-match-to-sample task. Front Psychol 2011; 2:85. [PMID: 21687454 PMCID: PMC3110394 DOI: 10.3389/fpsyg.2011.00085] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2011] [Accepted: 04/21/2011] [Indexed: 12/01/2022] Open
Abstract
In this study, we focus our investigation on task-specific cognitive modulation of early cortical auditory processing in human cerebral cortex. During the experiments, we acquired whole-head magnetoencephalography data while participants were performing an auditory delayed-match-to-sample (DMS) task and associated control tasks. Using a spatial filtering beamformer technique to simultaneously estimate multiple source activities inside the human brain, we observed a significant DMS-specific suppression of the auditory evoked response to the second stimulus in a sound pair, with the center of the effect being located in the vicinity of the left auditory cortex. For the right auditory cortex, a non-invariant suppression effect was observed in both DMS and control tasks. Furthermore, analysis of coherence revealed a beta band (12∼20 Hz) DMS-specific enhanced functional interaction between the sources in left auditory cortex and those in left inferior frontal gyrus, which has been shown to be involved in short-term memory processing during the delay period of DMS task. Our findings support the view that early evoked cortical responses to incoming acoustic stimuli can be modulated by task-specific cognitive functions by means of frontal–temporal functional interactions.
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Affiliation(s)
- Feng Rong
- Brain Imaging and Modeling Section, National Institute on Deafness and Other Communication Disorders, National Institutes of Health Bethesda, MD, USA
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Abstract
Sensory gating (SG) is a prevalent physiological process important for information filtering in complex systems. SG is evaluated by presenting repetitious stimuli and measuring the degree of neural inhibition that occurs. SG has been found to be impaired in several psychiatric disorders. Recent animal and human research has made great progress in the study of SG, and in this review we provide an overview of recent research on SG using different methods. Animal research has uncovered findings that suggest (1) SG is displayed by single neurons and can be similar to SG observed from scalp recordings in humans, (2) SG is found in numerous brain structures located in sensory, motor and limbic subregions, (3) SG can be significantly influenced by state changes of the organism, and (4) SG has a diverse pharmacological profile accented by a strong influence from nicotine receptor activation. Human research has addressed similar issues using deep electrode recordings of brain structures. These experiments have revealed that (1) SG can be found in cortical regions surrounding hippocampus, (2) the order of neural processing places hippocampal involvement during a later stage of sensory processing than originally thought, and (3) multiple subtypes of gating exist that could be dependent on different brain circuits and more or less influenced by alterations in organismal state. Animal and human research both have limitations. We emphasize the need for integrative approaches to understand the process and combine information between basic and clinical fields so that a more complete picture of SG will emerge.
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Affiliation(s)
- Howard C Cromwell
- Department of Psychology, Bowling Green State University, Ohio 43403, USA.
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