1
|
Koehler CC, Almassri LS, Tokar N, Mafi AM, O’Hara MJ, Young JW, Mellott JG. Age-related Changes of GAD1 mRNA Expression in the Central Inferior Colliculus. TRANSLATIONAL MEDICINE OF AGING 2023; 7:20-32. [PMID: 38111912 PMCID: PMC10727507 DOI: 10.1016/j.tma.2023.04.001] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2023] Open
Abstract
Encoding sounds with a high degree of temporal precision is an essential task for the inferior colliculus (IC) to perform and maintain the accurate processing of sounds and speech. However, the age-related reduction of GABAergic neurotransmission in the IC interrupts temporal precision and likely contributes to presbycusis. As presbycusis often manifests at high or low frequencies specifically, we sought to determine if the expression of mRNA for glutamic decarboxylase 1 (GAD1) is downregulated non-uniformly across the tonotopic axis or cell size range in the aging IC. Using single molecule in situ fluorescent hybridization across young, middle age and old Fisher Brown Norway rats (an aging model that acquires low frequency presbycusis) we quantified individual GAD1 mRNA in small, medium and large GABAergic cells. Our results demonstrate that small GABAergic cells in low frequency regions had ~58% less GAD1 in middle age and continued to decline into old age. In contrast, the amount of GAD1 mRNA in large cells in low frequency regions significantly increased with age. As several studies have shown that downregulation of GAD1 decreases the release of GABA, we interpret our results in two ways. First, the onset of presbycusis may be driven by small GABAergic cells downregulating GAD1. Second, as previous studies demonstrate that GAD67 expression is broadly downregulated in the old IC, perhaps the translation of GAD1 to GAD67 is interrupted in large GABAergic IC cells during aging. These results point to a potential genetic mechanism explaining reduced temporal precision in the aging IC, and in turn, presbycusis.
Collapse
Affiliation(s)
- Christina C. Koehler
- Department of Anatomy and Neurobiology Northeast Ohio Medical University Rootstown, OH USA
| | - Laila S. Almassri
- Department of Anatomy and Neurobiology Northeast Ohio Medical University Rootstown, OH USA
| | - Nick Tokar
- Department of Anatomy and Neurobiology Northeast Ohio Medical University Rootstown, OH USA
| | - Amir M. Mafi
- The Ohio State College of Medicine The Ohio State Columbus, OH USA
| | - Mitchell J. O’Hara
- Department of Anatomy and Neurobiology Northeast Ohio Medical University Rootstown, OH USA
| | - Jesse W. Young
- Department of Anatomy and Neurobiology Northeast Ohio Medical University Rootstown, OH USA
| | - Jeffrey G. Mellott
- Department of Anatomy and Neurobiology Northeast Ohio Medical University Rootstown, OH USA
| |
Collapse
|
2
|
Zhao M, Ren M, Jiang T, Jia X, Wang X, Li A, Li X, Luo Q, Gong H. Whole-Brain Direct Inputs to and Axonal Projections from Excitatory and Inhibitory Neurons in the Mouse Primary Auditory Area. Neurosci Bull 2022; 38:576-590. [DOI: 10.1007/s12264-022-00838-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2021] [Accepted: 12/26/2021] [Indexed: 11/29/2022] Open
|
3
|
Homma NY, Bajo VM. Lemniscal Corticothalamic Feedback in Auditory Scene Analysis. Front Neurosci 2021; 15:723893. [PMID: 34489635 PMCID: PMC8417129 DOI: 10.3389/fnins.2021.723893] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2021] [Accepted: 07/30/2021] [Indexed: 12/15/2022] Open
Abstract
Sound information is transmitted from the ear to central auditory stations of the brain via several nuclei. In addition to these ascending pathways there exist descending projections that can influence the information processing at each of these nuclei. A major descending pathway in the auditory system is the feedback projection from layer VI of the primary auditory cortex (A1) to the ventral division of medial geniculate body (MGBv) in the thalamus. The corticothalamic axons have small glutamatergic terminals that can modulate thalamic processing and thalamocortical information transmission. Corticothalamic neurons also provide input to GABAergic neurons of the thalamic reticular nucleus (TRN) that receives collaterals from the ascending thalamic axons. The balance of corticothalamic and TRN inputs has been shown to refine frequency tuning, firing patterns, and gating of MGBv neurons. Therefore, the thalamus is not merely a relay stage in the chain of auditory nuclei but does participate in complex aspects of sound processing that include top-down modulations. In this review, we aim (i) to examine how lemniscal corticothalamic feedback modulates responses in MGBv neurons, and (ii) to explore how the feedback contributes to auditory scene analysis, particularly on frequency and harmonic perception. Finally, we will discuss potential implications of the role of corticothalamic feedback in music and speech perception, where precise spectral and temporal processing is essential.
Collapse
Affiliation(s)
- Natsumi Y. Homma
- Center for Integrative Neuroscience, University of California, San Francisco, San Francisco, CA, United States
- Coleman Memorial Laboratory, Department of Otolaryngology – Head and Neck Surgery, University of California, San Francisco, San Francisco, CA, United States
| | - Victoria M. Bajo
- Department of Physiology, Anatomy and Genetics, University of Oxford, Oxford, United Kingdom
| |
Collapse
|
4
|
Zhang X, Ye X, Cheng R, Li Q, Xiao Z. An Emergent Discriminative Learning Is Elicited During Multifrequency Testing. Front Neurosci 2019; 13:1244. [PMID: 31824246 PMCID: PMC6881306 DOI: 10.3389/fnins.2019.01244] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2019] [Accepted: 11/04/2019] [Indexed: 11/29/2022] Open
Abstract
In auditory-conditioned fear learning, the freezing response is independent of the sound frequencies used, but the frequency of the conditioned sound is considered distinct from those of unrelated sounds based on electrophysiological responses in the auditory system. Whether an emergent discriminative learning underlies auditory fear conditioning and which nuclei and pathways are involved in it remain unclear. Using behavioral and electrophysiological assays, we found that the response of medial prefrontal cortex (mPFC) neurons to a conditioned auditory stimulus (CS) was enhanced relative to the response to unrelated frequencies (UFs) after auditory fear conditioning, and mice could distinguish the CS during multifrequency testing, a phenomenon called emergent discriminative learning. After silencing the mPFC with muscimol, emergent discriminative learning was blocked. In addition, the pure tone responses of mPFC neurons were inhibited after injection of lidocaine in the ipsilateral primary auditory cortex (A1), and the emergent discriminative learning was blocked by silencing both sides of A1 with muscimol. This study, therefore, provides evidence for an emergent discriminative learning mediated by mPFC and A1 neurons after auditory fear conditioning.
Collapse
Affiliation(s)
- Xingui Zhang
- Department of Physiology, School of Basic Medical Sciences, Key Laboratory of Psychiatric Disorders of Guangdong Province, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, China
| | - Xianhua Ye
- Department of Physiology, School of Basic Medical Sciences, Key Laboratory of Psychiatric Disorders of Guangdong Province, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, China
| | - Rui Cheng
- Department of Physiology, School of Basic Medical Sciences, Key Laboratory of Psychiatric Disorders of Guangdong Province, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, China
| | - Qi Li
- Department of Otolaryngology-Head and Neck Surgery, Nanfang Hospital, Southern Medical University, Guangzhou, China
| | - Zhongju Xiao
- Department of Physiology, School of Basic Medical Sciences, Key Laboratory of Psychiatric Disorders of Guangdong Province, Guangdong-Hong Kong-Macao Greater Bay Area Center for Brain Science and Brain-Inspired Intelligence, Key Laboratory of Mental Health of the Ministry of Education, Southern Medical University, Guangzhou, China
| |
Collapse
|
5
|
Inhibitory Projections from the Inferior Colliculus to the Medial Geniculate body Originate from Four Subtypes of GABAergic Cells. eNeuro 2018; 5:eN-NWR-0406-18. [PMID: 30456294 PMCID: PMC6240760 DOI: 10.1523/eneuro.0406-18.2018] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 10/25/2018] [Indexed: 12/26/2022] Open
Abstract
GABAergic cells constitute 20-40% of the cells that project from the inferior colliculus [(IC) a midbrain auditory hub] to the medial geniculate body [(MG) the main auditory nucleus of the thalamus]. Four subtypes of GABAergic IC cells have been identified based on their association with perineuronal nets (PNs) and dense rings of axosomatic terminals expressing vesicular glutamate transporter 2 (VGLUT2 rings). These subtypes differ in their soma size and distribution within the IC. Based on previous work emphasizing large GABAergic cells as the origin of GABAergic IC-MG projections, we hypothesized that GABAergic IC cells surrounded by PNs and VGLUT2 rings, which tend to have larger somas, were more likely to project to the MG than smaller cells lacking these extracellular markers. Here, we injected retrograde tract tracers into the MG of guinea pigs of either sex and analyzed retrogradely labeled GABAergic cells in the ipsilateral IC for soma size and association with PNs and/or VGLUT2 rings. We found a range of GABAergic soma sizes present within the IC-MG pathway, which were reflective of the full range of GABAergic soma sizes present within the IC. Further, we found that all four subtypes of GABAergic IC cells participate in the IC-MG pathway, and that GABAergic cells lacking PNs and VGLUT2 rings were more prevalent within the pathway than would be expected based on their overall prevalence in the IC. These results may provide an anatomical substrate for the multiple roles of inhibition in the IC-MG pathway, which have emerged in electrophysiological studies.
Collapse
|
6
|
Pre- and postsynaptic ionotropic glutamate receptors in the auditory system of mammals. Hear Res 2018; 362:1-13. [DOI: 10.1016/j.heares.2018.02.007] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/01/2017] [Revised: 02/16/2018] [Accepted: 02/21/2018] [Indexed: 01/22/2023]
|
7
|
Xiao C, Liu Y, Xu J, Gan X, Xiao Z. Septal and Hippocampal Neurons Contribute to Auditory Relay and Fear Conditioning. Front Cell Neurosci 2018; 12:102. [PMID: 29713265 PMCID: PMC5911473 DOI: 10.3389/fncel.2018.00102] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2018] [Accepted: 03/28/2018] [Indexed: 01/30/2023] Open
Abstract
The hippocampus has been thought to process auditory information. However, the properties, pathway, and role of hippocampal auditory responses are unclear. With loose-patch recordings, we found that hippocampal neurons are mainly responsive to noise and are not tonotopically organized. Their latencies are shorter than those of primary auditory cortical (A1) neurons but longer than those of medial septal (MS) neurons, suggesting that hippocampal auditory information comes from MS neurons rather than from A1 neurons. Silencing the MS blocks both hippocampal auditory responses and memory of auditory fear conditioning trained with noise and tone. Auditory fear conditioning was associated with some cues but not with a specific frequency of sound, as demonstrated by animals trained with noise, 2.5-, 5-, 10-, 15-, or 30-kHz tones, and tested with these sounds. Therefore, the noise responses of hippocampal neurons have identified a population of neurons that can be associated with auditory fear conditioning.
Collapse
Affiliation(s)
- Cuiyu Xiao
- Key Laboratory of Psychiatric Disorders of Guangdong Province, Department of Physiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Yun Liu
- Key Laboratory of Psychiatric Disorders of Guangdong Province, Department of Physiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Jian Xu
- Key Laboratory of Psychiatric Disorders of Guangdong Province, Department of Physiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Xiong Gan
- Key Laboratory of Psychiatric Disorders of Guangdong Province, Department of Physiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| | - Zhongju Xiao
- Key Laboratory of Psychiatric Disorders of Guangdong Province, Department of Physiology, School of Basic Medical Sciences, Southern Medical University, Guangzhou, China
| |
Collapse
|
8
|
Specialization of the auditory system for the processing of bio-sonar information in the frequency domain: Mustached bats. Hear Res 2018; 361:1-22. [DOI: 10.1016/j.heares.2018.01.012] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/23/2017] [Revised: 01/18/2018] [Accepted: 01/22/2018] [Indexed: 11/20/2022]
|
9
|
Zhang GW, Sun WJ, Zingg B, Shen L, He J, Xiong Y, Tao HW, Zhang LI. A Non-canonical Reticular-Limbic Central Auditory Pathway via Medial Septum Contributes to Fear Conditioning. Neuron 2018; 97:406-417.e4. [PMID: 29290554 PMCID: PMC5798467 DOI: 10.1016/j.neuron.2017.12.010] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2017] [Revised: 11/06/2017] [Accepted: 12/05/2017] [Indexed: 11/26/2022]
Abstract
In the mammalian brain, auditory information is known to be processed along a central ascending pathway leading to auditory cortex (AC). Whether there exist any major pathways beyond this canonical auditory neuraxis remains unclear. In awake mice, we found that auditory responses in entorhinal cortex (EC) cannot be explained by a previously proposed relay from AC based on response properties. By combining anatomical tracing and optogenetic/pharmacological manipulations, we discovered that EC received auditory input primarily from the medial septum (MS), rather than AC. A previously uncharacterized auditory pathway was then revealed: it branched from the cochlear nucleus, and via caudal pontine reticular nucleus, pontine central gray, and MS, reached EC. Neurons along this non-canonical auditory pathway responded selectively to high-intensity broadband noise, but not pure tones. Disruption of the pathway resulted in an impairment of specifically noise-cued fear conditioning. This reticular-limbic pathway may thus function in processing aversive acoustic signals.
Collapse
Affiliation(s)
- Guang-Wei Zhang
- Department of Neurobiology, Chongqing Key Laboratory of Neurobiology, Third Military Medical University, 30 Gaotanyan St., Chongqing, 400038, China; Zilkha Neurogenetic Institute, Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
| | - Wen-Jian Sun
- Zilkha Neurogenetic Institute, Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA; Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - Brian Zingg
- Zilkha Neurogenetic Institute, Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA; Neuroscience Graduate Program, University of Southern California, Los Angeles, CA 90089, USA
| | - Li Shen
- Zilkha Neurogenetic Institute, Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA
| | - Jufang He
- Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong
| | - Ying Xiong
- Department of Neurobiology, Chongqing Key Laboratory of Neurobiology, Third Military Medical University, 30 Gaotanyan St., Chongqing, 400038, China.
| | - Huizhong W Tao
- Zilkha Neurogenetic Institute, Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
| | - Li I Zhang
- Zilkha Neurogenetic Institute, Department of Physiology and Neuroscience, Keck School of Medicine, University of Southern California, Los Angeles, CA 90089, USA.
| |
Collapse
|
10
|
Schu S, Vancamp T. Clinical Aspects of Burst Stimulation for Pain Control. Neuromodulation 2018. [DOI: 10.1016/b978-0-12-805353-9.00052-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
|
11
|
Neurons, Connections, and Microcircuits of the Inferior Colliculus. THE MAMMALIAN AUDITORY PATHWAYS 2018. [DOI: 10.1007/978-3-319-71798-2_6] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
|
12
|
Jhangiani-Jashanmal IT, Yamamoto R, Gungor NZ, Paré D. Electroresponsive properties of rat central medial thalamic neurons. J Neurophysiol 2016; 115:1533-41. [PMID: 26763778 DOI: 10.1152/jn.00982.2015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2015] [Accepted: 01/12/2016] [Indexed: 11/22/2022] Open
Abstract
The central medial thalamic (CMT) nucleus is a poorly known component of the middle thalamic complex that relays nociceptive inputs to the basolateral amygdala and cingulate cortex and plays a critical role in the control of awareness. The present study was undertaken to characterize the electroresponsive properties of CMT neurons. Similar to relay neurons found throughout the dorsal thalamus, CMT cells assumed tonic or burst-firing modes, depending on their membrane potentials (Vm). However, they showed little evidence of the hyperpolarization-activated mixed cationic conductance (IH)-mediated inward rectification usually displayed by dorsal thalamic relay cells at hyperpolarized Vm Two subtypes of CMT neurons were identified when comparing their responses with depolarization applied from negative potentials. Some cells generated a low-threshold spike burst followed by tonic firing, whereas others remained silent after the initial burst, irrespective of the amount of depolarizing current injected. Equal proportions of the two cell types were found among neurons retrogradely labeled from the basolateral amygdala. Their morphological properties were heterogeneous but distinct from the classical bushy relay cell type that prevails in most of the dorsal thalamus. We propose that the marginal influence of IHin CMT relative to other dorsal thalamic nuclei has significant network-level consequences. Because IHpromotes the genesis of highly coherent delta oscillations in thalamocortical networks during sleep, these oscillations may be weaker or less coherent in CMT. Consequently, delta oscillations would be more easily disrupted by peripheral inputs, providing a potential mechanism for the reported role of CMT in eliciting arousal from sleep or anesthesia.
Collapse
Affiliation(s)
| | - Ryo Yamamoto
- Center for Molecular and Behavioral Neuroscience, Rutgers University-Newark, Newark, New Jersey
| | - Nur Zeynep Gungor
- Center for Molecular and Behavioral Neuroscience, Rutgers University-Newark, Newark, New Jersey
| | - Denis Paré
- Center for Molecular and Behavioral Neuroscience, Rutgers University-Newark, Newark, New Jersey
| |
Collapse
|
13
|
Synaptic mechanisms shaping delay-tuned combination-sensitivity in the auditory thalamus of mustached bats. Hear Res 2016; 331:69-82. [DOI: 10.1016/j.heares.2015.10.013] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/11/2015] [Revised: 09/24/2015] [Accepted: 10/20/2015] [Indexed: 11/21/2022]
|
14
|
Cai R, Caspary DM. GABAergic inhibition shapes SAM responses in rat auditory thalamus. Neuroscience 2015; 299:146-55. [PMID: 25943479 PMCID: PMC4457678 DOI: 10.1016/j.neuroscience.2015.04.062] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Revised: 04/27/2015] [Accepted: 04/27/2015] [Indexed: 01/03/2023]
Abstract
Auditory thalamus (medial geniculate body [MGB]) receives ascending inhibitory GABAergic inputs from inferior colliculus (IC) and descending GABAergic projections from the thalamic reticular nucleus (TRN) with both inputs postulated to play a role in shaping temporal responses. Previous studies suggested that enhanced processing of temporally rich stimuli occurs at the level of MGB, with our recent study demonstrating enhanced GABA sensitivity in MGB compared to IC. The present study used sinusoidal amplitude-modulated (SAM) stimuli to generate modulation transfer functions (MTFs), to examine the role of GABAergic inhibition in shaping the response properties of MGB single units in anesthetized rats. Rate MTFs (rMTFs) were parsed into "bandpass (BP)", "mixed (Mixed)", "highpass (HP)" or "atypical" response types, with most units showing the Mixed response type. GABAA receptor blockade with iontophoretic application of the GABAA receptor (GABAAR) antagonist gabazine (GBZ) selectively altered the response properties of most MGB neurons examined. Mixed and HP units showed significant GABAAR-mediated SAM-evoked rate response changes at higher modulation frequencies (fms), which were also altered by N-methyl-d-aspartic acid (NMDA) receptor blockade (2R)-amino-5-phosphonopentanoate (AP5). BP units, and the lower arm of Mixed units responded to GABAAR blockade with increased responses to SAM stimuli at or near the rate best modulation frequency (rBMF). The ability of GABA circuits to shape responses at higher modulation frequencies is an emergent property of MGB units, not observed at lower levels of the auditory pathway and may reflect activation of MGB NMDA receptors (Rabang and Bartlett, 2011; Rabang et al., 2012). Together, GABAARs exert selective rate control over selected fms, generally without changing the units' response type. These results showed that coding of modulated stimuli at the level of auditory thalamus is at least, in part, strongly controlled by GABA neurotransmission, in delicate balance with glutamatergic neurotransmission.
Collapse
Affiliation(s)
- R Cai
- Southern Illinois University School of Medicine, Department of Pharmacology, Springfield, IL, United States
| | - D M Caspary
- Southern Illinois University School of Medicine, Department of Pharmacology, Springfield, IL, United States.
| |
Collapse
|
15
|
Deviance detection in auditory subcortical structures: what can we learn from neurochemistry and neural connectivity? Cell Tissue Res 2015; 361:215-32. [DOI: 10.1007/s00441-015-2134-7] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Accepted: 01/22/2015] [Indexed: 12/18/2022]
|
16
|
De Ridder D, Vanneste S, Plazier M, Vancamp T. Mimicking the brain: evaluation of St Jude Medical's Prodigy Chronic Pain System with Burst Technology. Expert Rev Med Devices 2014; 12:143-50. [PMID: 25483825 DOI: 10.1586/17434440.2015.985652] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The Prodigy is a new type of internal pulse generator that controls the delivery of electrical stimuli to nervous tissue. It is capable of delivering burst stimulation, which is a novel waveform that consists of closely spaced high-frequency electrical impulses delivered in packets riding on a plateau, and followed by a quiescent period. Its inception was based on mimicking burst firing in the nervous system and usually delivered by unmyelinated fibers that uniformly have a motivational affective homeostatic function. It thereby targets a multimodal salience network, even though the stimuli are delivered at the level of the spinal cord. As such, it is specifically capable of influencing the affective/attentional components of pain. Burst stimulation was initially safely applied off-label to the auditory cortex for tinnitus, and later also to the spinal cord, the somatosensory cortex for neuropathic pain, subcutaneously for failed back surgery syndrome, and cingulate cortex for addiction and tinnitus.
Collapse
Affiliation(s)
- Dirk De Ridder
- Department of Surgical Sciences, Section of Neurosurgery, Dunedin School of Medicine, University of Otago, Dunedin, New Zealand
| | | | | | | |
Collapse
|
17
|
Mellott JG, Foster NL, Ohl AP, Schofield BR. Excitatory and inhibitory projections in parallel pathways from the inferior colliculus to the auditory thalamus. Front Neuroanat 2014; 8:124. [PMID: 25414646 PMCID: PMC4220731 DOI: 10.3389/fnana.2014.00124] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2014] [Accepted: 10/17/2014] [Indexed: 01/06/2023] Open
Abstract
Individual subdivisions of the medial geniculate body (MG) receive a majority of their ascending inputs from 1 or 2 subdivisions of the inferior colliculus (IC). This establishes parallel pathways that provide a model for understanding auditory projections from the IC through the MG and on to auditory cortex. A striking discovery about the tectothalamic circuit was identification of a substantial GABAergic component. Whether GABAergic projections match the parallel pathway organization has not been examined. We asked whether the parallel pathway concept is reflected in guinea pig tectothalamic pathways and to what degree GABAergic cells contribute to each pathway. We deposited retrograde tracers into individual MG subdivisions (ventral, MGv; medial, MGm; dorsal, MGd; suprageniculate, MGsg) to label tectothalamic cells and used immunochemistry to identify GABAergic cells. The MGv receives most of its IC input (~75%) from the IC central nucleus (ICc); MGd and MGsg receive most of their input (~70%) from IC dorsal cortex (ICd); and MGm receives substantial input from both ICc (~40%) and IC lateral cortex (~40%). Each MG subdivision receives additional input (up to 32%) from non-dominant IC subdivisions, suggesting cross-talk between the pathways. The proportion of GABAergic cells in each pathway depended on the MG subdivision. GABAergic cells formed ~20% of IC inputs to MGv or MGm, ~11% of inputs to MGd, and 4% of inputs to MGsg. Thus, non-GABAergic (i.e., glutamatergic) cells are most numerous in each pathway with GABAergic cells contributing to different extents. Despite smaller numbers of GABAergic cells, their distributions across IC subdivisions mimicked the parallel pathways. Projections outside the dominant pathways suggest opportunities for excitatory and inhibitory crosstalk. The results demonstrate parallel tectothalamic pathways in guinea pigs and suggest numerous opportunities for excitatory and inhibitory interactions within and between pathways.
Collapse
Affiliation(s)
- Jeffrey G Mellott
- Department of Anatomy and Neurobiology, Northeast Ohio Medical University Rootstown, OH, USA
| | - Nichole L Foster
- Department of Anatomy and Neurobiology, Northeast Ohio Medical University Rootstown, OH, USA ; School of Biomedical Sciences, Kent State University Kent, OH, USA
| | - Andrew P Ohl
- Department of Anatomy and Neurobiology, Northeast Ohio Medical University Rootstown, OH, USA
| | - Brett R Schofield
- Department of Anatomy and Neurobiology, Northeast Ohio Medical University Rootstown, OH, USA ; School of Biomedical Sciences, Kent State University Kent, OH, USA
| |
Collapse
|
18
|
Mellott JG, Bickford ME, Schofield BR. Descending projections from auditory cortex to excitatory and inhibitory cells in the nucleus of the brachium of the inferior colliculus. Front Syst Neurosci 2014; 8:188. [PMID: 25339870 PMCID: PMC4186273 DOI: 10.3389/fnsys.2014.00188] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2014] [Accepted: 09/16/2014] [Indexed: 01/13/2023] Open
Abstract
Descending projections from the auditory cortex (AC) terminate in subcortical auditory centers from the medial geniculate nucleus (MG) to the cochlear nucleus, allowing the AC to modulate the processing of acoustic information at many levels of the auditory system. The nucleus of the brachium of the inferior colliculus (NBIC) is a large midbrain auditory nucleus that is a target of these descending cortical projections. The NBIC is a source of several auditory projections, including an ascending projection to the MG. This ascending projection appears to originate from both excitatory and inhibitory NBIC cells, but whether the cortical projections contact either of these cell groups is unknown. In this study, we first combined retrograde tracing and immunochemistry for glutamic acid decarboxylase (GAD, a marker of GABAergic cells) to identify GABAergic and non-GABAergic NBIC projections to the MG. Our first result is that GAD-immunopositive cells constitute ~17% of the NBIC to MG projection. We then used anterograde labeling and electron microscopy to examine the AC projection to the NBIC. Our second result is that cortical boutons in the NBIC form synapses with round vesicles and asymmetric synapses, consistent with excitatory effects. Finally, we combined fluorescent anterograde labeling of corticofugal axons with immunochemistry and retrograde labeling of NBIC cells that project to the MG. These final results suggest first that AC axons contact both GAD-negative and GAD-positive NBIC cells and, second, that some of cortically-contacted cells project to the MG. Overall, the results imply that corticofugal projections can modulate both excitatory and inhibitory ascending projections from the NBIC to the auditory thalamus.
Collapse
Affiliation(s)
- Jeffrey G Mellott
- Department of Anatomy and Neurobiology, Northeast Ohio Medical University Rootstown, OH USA
| | - Martha E Bickford
- Department of Anatomical Sciences and Neurobiology, University of Louisville Louisville, KY USA
| | - Brett R Schofield
- Department of Anatomy and Neurobiology, Northeast Ohio Medical University Rootstown, OH USA
| |
Collapse
|
19
|
Kong L, Xiong C, Li L, Yan J. Frequency-specific corticofugal modulation of the dorsal cochlear nucleus in mice. Front Syst Neurosci 2014; 8:125. [PMID: 25071477 PMCID: PMC4076887 DOI: 10.3389/fnsys.2014.00125] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2014] [Accepted: 06/16/2014] [Indexed: 01/03/2023] Open
Abstract
The primary auditory cortex (AI) modulates the sound information processing in the lemniscal subcortical nuclei, including the anteroventral cochlear nucleus (AVCN), in a frequency-specific manner. The dorsal cochlear nucleus (DCN) is a non-lemniscal subcortical nucleus but it is tonotopically organized like the AVCN. However, it remains unclear how the AI modulates the sound information processing in the DCN. This study examined the impact of focal electrical stimulation of AI on the auditory responses of the DCN neurons in mice. We found that the electrical stimulation induced significant changes in the best frequency (BF) of DCN neurons. The changes in the BFs were highly specific to the BF differences between the stimulated AI neurons and the recorded DCN neurons. The DCN BFs shifted higher when the AI BFs were higher than the DCN BFs and the DCN BFs shifted lower when the AI BFs were lower than the DCN BFs. The DCN BFs showed no change when the AI and DCN BFs were similar. Moreover, the BF shifts were linearly correlated to the BF differences. Thus, our data suggest that corticofugal modulation of the DCN is also highly specific to frequency information, similar to the corticofugal modulation of the AVCN. The frequency-specificity of corticofugal modulation does not appear limited to the lemniscal ascending pathway.
Collapse
Affiliation(s)
- Lingzhi Kong
- Department of Physiology and Pharmacology, Faculty of Medicine, Hotchkiss Brain Institute, University of Calgary Calgary, AB, Canada
| | - Colin Xiong
- Department of Physiology and Pharmacology, Faculty of Medicine, Hotchkiss Brain Institute, University of Calgary Calgary, AB, Canada
| | - Liang Li
- Department of Psychology, Department of Machine Intelligence, Speech and Hearing Research Center, Key Laboratory on Machine Perception (Ministry of Education), PKU-IDG/McGovern Institute for Brain Research, Peking University Beijing, China
| | - Jun Yan
- Department of Physiology and Pharmacology, Faculty of Medicine, Hotchkiss Brain Institute, University of Calgary Calgary, AB, Canada
| |
Collapse
|
20
|
Antunes FM, Malmierca MS. An Overview of Stimulus-Specific Adaptation in the Auditory Thalamus. Brain Topogr 2013; 27:480-99. [DOI: 10.1007/s10548-013-0342-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2013] [Accepted: 12/05/2013] [Indexed: 12/30/2022]
|
21
|
Honma Y, Tsukano H, Horie M, Ohshima S, Tohmi M, Kubota Y, Takahashi K, Hishida R, Takahashi S, Shibuki K. Auditory cortical areas activated by slow frequency-modulated sounds in mice. PLoS One 2013; 8:e68113. [PMID: 23874516 PMCID: PMC3714279 DOI: 10.1371/journal.pone.0068113] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Accepted: 05/24/2013] [Indexed: 11/18/2022] Open
Abstract
Species-specific vocalizations in mice have frequency-modulated (FM) components slower than the lower limit of FM direction selectivity in the core region of the mouse auditory cortex. To identify cortical areas selective to slow frequency modulation, we investigated tonal responses in the mouse auditory cortex using transcranial flavoprotein fluorescence imaging. For differentiating responses to frequency modulation from those to stimuli at constant frequencies, we focused on transient fluorescence changes after direction reversal of temporally repeated and superimposed FM sweeps. We found that the ultrasonic field (UF) in the belt cortical region selectively responded to the direction reversal. The dorsoposterior field (DP) also responded weakly to the reversal. Regarding the responses in UF, no apparent tonotopic map was found, and the right UF responses were significantly larger in amplitude than the left UF responses. The half-max latency in responses to FM sweeps was shorter in UF compared with that in the primary auditory cortex (A1) or anterior auditory field (AAF). Tracer injection experiments in the functionally identified UF and DP confirmed that these two areas receive afferent inputs from the dorsal part of the medial geniculate nucleus (MG). Calcium imaging of UF neurons stained with fura-2 were performed using a two-photon microscope, and the presence of UF neurons that were selective to both direction and direction reversal of slow frequency modulation was demonstrated. These results strongly suggest a role for UF, and possibly DP, as cortical areas specialized for processing slow frequency modulation in mice.
Collapse
Affiliation(s)
- Yuusuke Honma
- Department of Neurophysiology, Brain Research Institute, Niigata University, Asahi-machi, Niigata, Japan
- Department of Otolaryngology, Faculty of Medicine, Niigata University, Asahi-machi, Niigata, Japan
| | - Hiroaki Tsukano
- Department of Neurophysiology, Brain Research Institute, Niigata University, Asahi-machi, Niigata, Japan
| | - Masao Horie
- Department of Anatomy, Faculty of Medicine, Niigata University, Asahi-machi, Niigata, Japan
| | - Shinsuke Ohshima
- Department of Otolaryngology, Faculty of Medicine, Niigata University, Asahi-machi, Niigata, Japan
| | - Manavu Tohmi
- Department of Neurophysiology, Brain Research Institute, Niigata University, Asahi-machi, Niigata, Japan
| | - Yamato Kubota
- Department of Otolaryngology, Faculty of Medicine, Niigata University, Asahi-machi, Niigata, Japan
| | - Kuniyuki Takahashi
- Department of Otolaryngology, Faculty of Medicine, Niigata University, Asahi-machi, Niigata, Japan
| | - Ryuichi Hishida
- Department of Neurophysiology, Brain Research Institute, Niigata University, Asahi-machi, Niigata, Japan
| | - Sugata Takahashi
- Department of Otolaryngology, Faculty of Medicine, Niigata University, Asahi-machi, Niigata, Japan
| | - Katsuei Shibuki
- Department of Neurophysiology, Brain Research Institute, Niigata University, Asahi-machi, Niigata, Japan
- * E-mail:
| |
Collapse
|
22
|
Bartlett EL. The organization and physiology of the auditory thalamus and its role in processing acoustic features important for speech perception. BRAIN AND LANGUAGE 2013; 126:29-48. [PMID: 23725661 PMCID: PMC3707394 DOI: 10.1016/j.bandl.2013.03.003] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2012] [Revised: 02/28/2013] [Accepted: 03/19/2013] [Indexed: 05/17/2023]
Abstract
The auditory thalamus, or medial geniculate body (MGB), is the primary sensory input to auditory cortex. Therefore, it plays a critical role in the complex auditory processing necessary for robust speech perception. This review will describe the functional organization of the thalamus as it relates to processing acoustic features important for speech perception, focusing on thalamic nuclei that relate to auditory representations of language sounds. The MGB can be divided into three main subdivisions, the ventral, dorsal, and medial subdivisions, each with different connectivity, auditory response properties, neuronal properties, and synaptic properties. Together, the MGB subdivisions actively and dynamically shape complex auditory processing and form ongoing communication loops with auditory cortex and subcortical structures.
Collapse
|
23
|
Topographic distribution, frequency, and intensity dependence of stimulus-specific adaptation in the inferior colliculus of the rat. J Neurosci 2013; 32:17762-74. [PMID: 23223296 DOI: 10.1523/jneurosci.3190-12.2012] [Citation(s) in RCA: 75] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The ability to detect unexpected sounds within the environment is an important function of the auditory system, as a rapid response may be required for the organism to survive. Previous studies found a decreased response to repetitive stimuli (standard), but an increased response to rare or less frequent sounds (deviant) in individual neurons in the inferior colliculus (IC) and at higher levels. This phenomenon, known as stimulus-specific adaptation (SSA) has been suggested to underpin change detection. Currently, it is not known how SSA varies within a single neuron receptive field, i.e., it is unclear whether SSA is a unique property of the neuron or a feature that is frequency and/or intensity dependent. In the present experiments, we used the common SSA index (CSI) to quantify and compare the degree of SSA under different stimulation conditions in the IC of the rat. We calculated the CSI at different intensities and frequencies for each individual IC neuron to map the neuronal CSI within the receptive field. Our data show that high SSA is biased toward the high-frequency and low-intensity regions of the receptive field. We also find that SSA is better represented in the earliest portions of the response, and there is a positive correlation between the width of the frequency response area of the neuron and the maximum level of SSA. The present data suggest that SSA in the IC is not mediated by the intrinsic membrane properties of the neurons and instead might be related to an excitatory and/or inhibitory input segregation.
Collapse
|
24
|
Langguth B, De Ridder D. Tinnitus: therapeutic use of superficial brain stimulation. HANDBOOK OF CLINICAL NEUROLOGY 2013; 116:441-467. [PMID: 24112915 DOI: 10.1016/b978-0-444-53497-2.00036-x] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Tinnitus is a common disorder and traditional treatment approaches such as medication, active or passive sound enhancement, and cognitive behavioral therapy have limited efficacy. Thus, there is an urgent need for more effective treatment approaches. Functional imaging studies in patients with tinnitus have revealed alterations in neuronal activity of central auditory pathways, probably resulting as a consequence of sensory deafferentation. However, nonauditory brain areas are also involved. These nonauditory brain areas might represent both an "awareness" network involved in the conscious perception of the tinnitus signal as well as areas related to a nontinnitus-specific distress network consisting of the anterior cingulate cortex, anterior insula, and amygdala. Moreover, memory mechanisms involving the hippocampus and the parahippocampal region may play a role in the persistence of the awareness of the phantom percept, as well as in the reinforcement of the associated distress. All of these networks represent potential targets for treatment via pharmacological treatment or noninvasive and invasive brain stimulation. Repetitive transcranial magnetic stimulation (rTMS) is a noninvasive method of applying electromagnetic fields to the brain that can induce alterations of neuronal activity that outlast the stimulation period. Single sessions of rTMS over the temporal or temporoparietal cortex have been successful in transiently reducing tinnitus perception. Repeated sessions of rTMS have resulted in tinnitus relief in a subgroup of patients, lasting from several days to several months. However, effect sizes of rTMS in the treatment of tinnitus are only moderate, and interindividual variability is high. Larger and longer lasting effects have been observed with direct electrical stimulation of the auditory cortex via implanted epidural electrodes. Transcranial direct current stimulation (tDCS) has also shown potential for the treatment of tinnitus. Both auditory and frontal tDCS have shown tinnitus reduction in a subgroup of patients. In spite of the promising results of the different brain stimulation approaches, further research is needed before these techniques can be recommended for routine clinical use.
Collapse
Affiliation(s)
- Berthold Langguth
- Interdisciplinary Tinnitus Clinic, Department of Psychiatry and Psychotherapy, University of Regensburg, Regensburg, Germany.
| | | |
Collapse
|
25
|
Zhang J. Auditory cortex stimulation to suppress tinnitus: mechanisms and strategies. Hear Res 2012; 295:38-57. [PMID: 22683861 DOI: 10.1016/j.heares.2012.05.007] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/04/2012] [Revised: 05/06/2012] [Accepted: 05/14/2012] [Indexed: 01/08/2023]
Abstract
Brain stimulation is an important method used to modulate neural activity and suppress tinnitus. Several auditory and non-auditory brain regions have been targeted for stimulation. This paper reviews recent progress on auditory cortex (AC) stimulation to suppress tinnitus and its underlying neural mechanisms and stimulation strategies. At the same time, the author provides his opinions and hypotheses on both animal and human models. The author also proposes a medial geniculate body (MGB)-thalamic reticular nucleus (TRN)-Gating mechanism to reflect tinnitus-related neural information coming from upstream and downstream projection structures. The upstream structures include the lower auditory brainstem and midbrain structures. The downstream structures include the AC and certain limbic centers. Both upstream and downstream information is involved in a dynamic gating mechanism in the MGB together with the TRN. When abnormal gating occurs at the thalamic level, the spilled-out information interacts with the AC to generate tinnitus. The tinnitus signals at the MGB-TRN-Gating may be modulated by different forms of stimulations including brain stimulation. Each stimulation acts as a gain modulator to control the level of tinnitus signals at the MGB-TRN-Gate. This hypothesis may explain why different types of stimulation can induce tinnitus suppression. Depending on the tinnitus etiology, MGB-TRN-Gating may be different in levels and dynamics, which cause variability in tinnitus suppression induced by different gain controllers. This may explain why the induced suppression of tinnitus by one type of stimulation varies across individual patients.
Collapse
Affiliation(s)
- Jinsheng Zhang
- Department of Otolaryngology - Head and Neck Surgery, Wayne State University, School of Medicine, 5E-UHC, 4201 Saint Antoine, Detroit, MI 48201, USA.
| |
Collapse
|
26
|
Langguth B, Schecklmann M, Lehner A, Landgrebe M, Poeppl TB, Kreuzer PM, Schlee W, Weisz N, Vanneste S, De Ridder D. Neuroimaging and neuromodulation: complementary approaches for identifying the neuronal correlates of tinnitus. Front Syst Neurosci 2012; 6:15. [PMID: 22509155 PMCID: PMC3321434 DOI: 10.3389/fnsys.2012.00015] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2012] [Accepted: 03/01/2012] [Indexed: 11/13/2022] Open
Abstract
An inherent limitation of functional imaging studies is their correlational approach. More information about critical contributions of specific brain regions can be gained by focal transient perturbation of neural activity in specific regions with non-invasive focal brain stimulation methods. Functional imaging studies have revealed that tinnitus is related to alterations in neuronal activity of central auditory pathways. Modulation of neuronal activity in auditory cortical areas by repetitive transcranial magnetic stimulation (rTMS) can reduce tinnitus loudness and, if applied repeatedly, exerts therapeutic effects, confirming the relevance of auditory cortex activation for tinnitus generation and persistence. Measurements of oscillatory brain activity before and after rTMS demonstrate that the same stimulation protocol has different effects on brain activity in different patients, presumably related to interindividual differences in baseline activity in the clinically heterogeneous study cohort. In addition to alterations in auditory pathways, imaging techniques also indicate the involvement of non-auditory brain areas, such as the fronto-parietal "awareness" network and the non-tinnitus-specific distress network consisting of the anterior cingulate cortex, anterior insula, and amygdale. Involvement of the hippocampus and the parahippocampal region putatively reflects the relevance of memory mechanisms in the persistence of the phantom percept and the associated distress. Preliminary studies targeting the dorsolateral prefrontal cortex, the dorsal anterior cingulate cortex, and the parietal cortex with rTMS and with transcranial direct current stimulation confirm the relevance of the mentioned non-auditory networks. Available data indicate the important value added by brain stimulation as a complementary approach to neuroimaging for identifying the neuronal correlates of the various clinical aspects of tinnitus.
Collapse
Affiliation(s)
- Berthold Langguth
- Department of Psychiatry and Psychotherapy, University of Regensburg Regensburg, Germany
| | | | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Rabang CF, Bartlett EL. A computational model of cellular mechanisms of temporal coding in the medial geniculate body (MGB). PLoS One 2011; 6:e29375. [PMID: 22195049 PMCID: PMC3241713 DOI: 10.1371/journal.pone.0029375] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2011] [Accepted: 11/28/2011] [Indexed: 12/04/2022] Open
Abstract
Acoustic stimuli are often represented in the early auditory pathway as patterns of neural activity synchronized to time-varying features. This phase-locking predominates until the level of the medial geniculate body (MGB), where previous studies have identified two main, largely segregated response types: Stimulus-synchronized responses faithfully preserve the temporal coding from its afferent inputs, and Non-synchronized responses, which are not phase locked to the inputs, represent changes in temporal modulation by a rate code. The cellular mechanisms underlying this transformation from phase-locked to rate code are not well understood. We use a computational model of a MGB thalamocortical neuron to test the hypothesis that these response classes arise from inferior colliculus (IC) excitatory afferents with divergent properties similar to those observed in brain slice studies. Large-conductance inputs exhibiting synaptic depression preserved input synchrony as short as 12.5 ms interclick intervals, while maintaining low firing rates and low-pass filtering responses. By contrast, small-conductance inputs with Mixed plasticity (depression of AMPA-receptor component and facilitation of NMDA-receptor component) desynchronized afferent inputs, generated a click-rate dependent increase in firing rate, and high-pass filtered the inputs. Synaptic inputs with facilitation often permitted band-pass synchrony along with band-pass rate tuning. These responses could be tuned by changes in membrane potential, strength of the NMDA component, and characteristics of synaptic plasticity. These results demonstrate how the same synchronized input spike trains from the inferior colliculus can be transformed into different representations of temporal modulation by divergent synaptic properties.
Collapse
Affiliation(s)
- Cal F. Rabang
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana, United States of America
| | - Edward L. Bartlett
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana, United States of America
- Department of Biological Sciences, Purdue University, West Lafayette, Indiana, United States of America
- * E-mail:
| |
Collapse
|
28
|
A possible role for a paralemniscal auditory pathway in the coding of slow temporal information. Hear Res 2010; 272:125-34. [PMID: 21094680 DOI: 10.1016/j.heares.2010.10.009] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/17/2010] [Revised: 09/27/2010] [Accepted: 10/19/2010] [Indexed: 11/20/2022]
Abstract
Low-frequency temporal information present in speech is critical for normal perception, however the neural mechanism underlying the differentiation of slow rates in acoustic signals is not known. Data from the rat trigeminal system suggest that the paralemniscal pathway may be specifically tuned to code low-frequency temporal information. We tested whether this phenomenon occurs in the auditory system by measuring the representation of temporal rate in lemniscal and paralemniscal auditory thalamus and cortex in guinea pig. Similar to the trigeminal system, responses measured in auditory thalamus indicate that slow rates are differentially represented in a paralemniscal pathway. In cortex, both lemniscal and paralemniscal neurons indicated sensitivity to slow rates. We speculate that a paralemniscal pathway in the auditory system may be specifically tuned to code low-frequency temporal information present in acoustic signals. These data suggest that somatosensory and auditory modalities have parallel sub-cortical pathways that separately process slow rates and the spatial representation of the sensory periphery.
Collapse
|
29
|
De Ridder D, Vanneste S, van der Loo E, Plazier M, Menovsky T, van de Heyning P. Burst stimulation of the auditory cortex: a new form of neurostimulation for noise-like tinnitus suppression. J Neurosurg 2010; 112:1289-94. [DOI: 10.3171/2009.10.jns09298] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object
Tinnitus is an auditory phantom percept related to tonic and burst hyperactivity of the auditory system. Two parallel pathways supply auditory information to the cerebral cortex: the tonotopically organized lemniscal system, and the nontonotopic extralemniscal system, which fire in tonic and burst mode, respectively. Electrical cortex stimulation is a method capable of modulating activity of the human cortex by delivering stimuli in a tonic or burst way. Burst firing is shown to be more powerful in activating the cerebral cortex than tonic firing, and bursts may activate neurons that are not activated by tonic firing.
Methods
Five patients with an implanted electrode on the auditory cortex were asked to rate their tinnitus distress and intensity on a visual analog scale before and after 40-Hz tonic and 40-Hz burst (5 pulses at 500 Hz) stimulation. All patients presented with both high-pitched pure tone and white noise components in their tinnitus.
Results
A significantly better suppression for narrowband noise tinnitus with burst stimulation in comparison with tonic stimulation (Z = −2.03, p = 0.04) was found. For pure tone tinnitus, no difference was found between tonic and burst stimulation (Z = −0.58, p = 0.56). No significant effect was obtained for stimulation amplitude (Z = −1.21, p = 0.23) and electrical charge per pulse (Z = −0.67, p = 0.50) between tonic and burst stimulation. The electrical current delivery per second was significantly different (Z = −2.02, p = 0.04).
Conclusions
Burst stimulation is a new form of neurostimulation that might be helpful in treating symptoms that are intractable to conventional tonic stimulation. Further exploration of this new stimulation design is warranted.
Collapse
Affiliation(s)
- Dirk De Ridder
- 1BRAI2N (Brain Research Center Antwerp for Innovative and Interdisciplinary Neuromodulation); and
- 2Departments of Neurosurgery and
| | - Sven Vanneste
- 1BRAI2N (Brain Research Center Antwerp for Innovative and Interdisciplinary Neuromodulation); and
- 2Departments of Neurosurgery and
| | - Elsa van der Loo
- 1BRAI2N (Brain Research Center Antwerp for Innovative and Interdisciplinary Neuromodulation); and
- 2Departments of Neurosurgery and
| | - Mark Plazier
- 1BRAI2N (Brain Research Center Antwerp for Innovative and Interdisciplinary Neuromodulation); and
- 2Departments of Neurosurgery and
| | - Tomas Menovsky
- 1BRAI2N (Brain Research Center Antwerp for Innovative and Interdisciplinary Neuromodulation); and
- 2Departments of Neurosurgery and
| | | |
Collapse
|
30
|
Dugué P, Le Bouquin-Jeannès R, Edeline JM, Faucon G. A physiologically based model for temporal envelope encoding in human primary auditory cortex. Hear Res 2010; 268:133-44. [PMID: 20685388 DOI: 10.1016/j.heares.2010.05.014] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/12/2009] [Revised: 05/17/2010] [Accepted: 05/21/2010] [Indexed: 10/19/2022]
Abstract
Communication sounds exhibit temporal envelope fluctuations in the low frequency range (<70 Hz) and human speech has prominent 2-16 Hz modulations with a maximum at 3-4 Hz. Here, we propose a new phenomenological model of the human auditory pathway (from cochlea to primary auditory cortex) to simulate responses to amplitude-modulated white noise. To validate the model, performance was estimated by quantifying temporal modulation transfer functions (TMTFs). Previous models considered either the lower stages of the auditory system (up to the inferior colliculus) or only the thalamocortical loop. The present model, divided in two stages, is based on anatomical and physiological findings and includes the entire auditory pathway. The first stage, from the outer ear to the colliculus, incorporates inhibitory interneurons in the cochlear nucleus to increase performance at high stimuli levels. The second stage takes into account the anatomical connections of the thalamocortical system and includes the fast and slow excitatory and inhibitory currents. After optimizing the parameters of the model to reproduce the diversity of TMTFs obtained from human subjects, a patient-specific model was derived and the parameters were optimized to effectively reproduce both spontaneous activity and the oscillatory part of the evoked response.
Collapse
|
31
|
Ojima H, Murakami K. Triadic synaptic interactions of large corticothalamic terminals in non-lemniscal thalamic nuclei of the cat auditory system. Hear Res 2010; 274:40-7. [PMID: 20685244 DOI: 10.1016/j.heares.2010.05.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2010] [Revised: 05/06/2010] [Accepted: 05/18/2010] [Indexed: 11/25/2022]
Abstract
Large corticothalamic (CT) terminals, presumed to originate from cortical layer 5 pyramidal cells, are distributed predominantly in non-specific thalamic nuclei in mammals. In the auditory system, little is known about whether these CT projections participate in the synaptic aggregation referred to as the triad. We studied synaptic interactions of these terminals with neuronal elements in one of the auditory non-lemniscal thalamic nuclei, the dorsal nucleus of the medial geniculate complex (MGC), in cats. After injections of an anterograde tracer in the primary auditory cortex, areas containing labeled large terminals were examined using an electron microscope. It was revealed that a fraction of large CT terminals participated in complicated synaptic arrangements: labeled terminals making synaptic contacts with vesicle-free dendrites, probably of thalamic principal neurons, and/or vesicle-filled neuronal profiles, probably of presynaptic dendrites (PSDs) of interneurons. In reconstructions or even in single sections, we found that these synaptic connections participated in triadic arrangements. Thus, PSDs postsynaptic to the labeled CT terminals were in turn presynaptic to the vesicle-free dendrites.
Collapse
Affiliation(s)
- Hisayuki Ojima
- Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo 113-8749, Japan.
| | | |
Collapse
|
32
|
Lee CC, Sherman SM. Drivers and modulators in the central auditory pathways. Front Neurosci 2010; 4:79. [PMID: 20589100 PMCID: PMC2920527 DOI: 10.3389/neuro.01.014.2010] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2009] [Accepted: 01/26/2010] [Indexed: 11/19/2022] Open
Abstract
The classic view of auditory information flow depicts a simple serial route from the periphery through tonotopically-organized nuclei in the brainstem, midbrain and thalamus, ascending eventually to the neocortex. Yet, complicating this picture are numerous parallel ascending and descending pathways, whose roles in auditory processing are poorly defined. To address this ambiguity, we have identified several anatomical and physiological properties that distinguish the auditory glutamatergic pathways into two groups that we have termed “drivers” and “modulators”. Driver pathways are associated with information-bearing pathways, while modulator pathways modify these principal information streams. These properties illuminate the potential roles of some previously ill-defined auditory pathways, and may be extended further to categorize either unknown or mischaracterized pathways throughout the auditory system.
Collapse
Affiliation(s)
- Charles C Lee
- Department of Neurobiology, University of Chicago Chicago, IL, USA
| | | |
Collapse
|
33
|
Topography and physiology of ascending streams in the auditory tectothalamic pathway. Proc Natl Acad Sci U S A 2009; 107:372-7. [PMID: 20018757 DOI: 10.1073/pnas.0907873107] [Citation(s) in RCA: 71] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Auditory information is relayed from the cochlea along parallel pathways and reaches the inferior colliculus (IC) and the medial geniculate body (MGB) en route to the cortex. Although the ascending tectothalamic pathway to the ventral division of the MGB is regarded as a high-fidelity information-bearing channel, the roles of the pathways to the dorsal and medial divisions are more opaque. Here, we show fundamental differences between these ascending pathways using an in vitro slice preparation. Using photostimulation, we found three main patterns of input (excitatory, inhibitory, and mixed) that differed in each pathway. Furthermore, electrical stimulation of the central nucleus of the IC evoked a depressing response in the MGB with no metabotropic glutamate (mGlu) receptor component, whereas stimulation of the lateral cortex of the IC evoked a facilitating response with an mGlu receptor component. These data suggest that the ascending tectothalamic pathways are functionally distinct from one another.
Collapse
|
34
|
Reprint of “frequency tuning and firing pattern properties of auditory thalamic neurons: An in vivo intracellular recording from the guinea pig” [Neuroscience 151 (2008) 293–302]☆. Neuroscience 2008; 154:273-82. [DOI: 10.1016/s0306-4522(08)00741-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/04/2007] [Indexed: 11/21/2022]
|
35
|
Llano DA, Sherman SM. Evidence for nonreciprocal organization of the mouse auditory thalamocortical-corticothalamic projection systems. J Comp Neurol 2008; 507:1209-27. [PMID: 18181153 DOI: 10.1002/cne.21602] [Citation(s) in RCA: 112] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
We tested the hypothesis that information is routed from one area of the auditory cortex (AC) to another via the dorsal division of the medial geniculate body (MGBd) by analyzing the degree of reciprocal connectivity between the auditory thalamus and cortex. Biotinylated dextran amine injected into the primary AC (AI) or anterior auditory field (AAF) of mice produced large, "driver-type" terminals primarily in the MGBd, with essentially no such terminals in the ventral MGB (MGBv). In contrast, small, "modulator-type" terminals were found primarily in the MGBv, and this coincided with areas of retrogradely labeled thalamocortical cell bodies. After MGBv injections, anterograde label was observed in layers 4 and 6 of the AI and AAF, which coincided with retrogradely labeled layer 6 cell bodies. After MGBd injections, thalamocortical terminals were seen in layers 1, 4, and 6 of the secondary AC and dorsoposterior AC, which coincided with labeled layer 6 cell bodies. Notably, after MGBd injection, a substantial number of layer 5 cells were labeled in all AC areas, whereas very few were seen after MGBv injection. Further, the degree of anterograde label in layer 4 of cortical columns containing labeled layer 6 cell bodies was greater than in columns containing labeled layer 5 cell bodies. These data suggest that auditory layer 5 corticothalamic projections are targeted to the MGBd in a nonreciprocal fashion and that the MGBd may route this information to the nonprimary AC.
Collapse
Affiliation(s)
- Daniel A Llano
- Department of Neurology, University of Chicago, Chicago, Illinois 60637, USA.
| | | |
Collapse
|
36
|
Frequency tuning and firing pattern properties of auditory thalamic neurons: An in vivo intracellular recording from the guinea pig. Neuroscience 2008; 151:293-302. [DOI: 10.1016/j.neuroscience.2007.09.082] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2007] [Revised: 08/30/2007] [Accepted: 11/07/2007] [Indexed: 11/18/2022]
|
37
|
De Ridder D, van der Loo E, Van der Kelen K, Menovsky T, van de Heyning P, Moller A. Theta, alpha and beta burst transcranial magnetic stimulation: brain modulation in tinnitus. Int J Med Sci 2007; 4:237-41. [PMID: 17952199 PMCID: PMC2016868 DOI: 10.7150/ijms.4.237] [Citation(s) in RCA: 81] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2007] [Accepted: 10/08/2007] [Indexed: 11/17/2022] Open
Abstract
INTRODUCTION Some forms of tinnitus are considered to be auditory phantom phenomena related to reorganization and hyperactivity of the auditory central nervous system. Repetitive transcranial magnetic stimulation (rTMS) is a non-invasive tool capable of modulating human brain activity, using single pulse or burst stimuli. Burst rTMS has only been performed in the theta range, and has not been used clinically. The authors analyze whether burst TMS at theta (5 Hz), alpha (10 Hz) and beta (20 Hz) frequencies can temporarily suppress narrow band noise/white noise tinnitus, which has been demonstrated to be intractable to tonic stimulation. METHODS rTMS is performed both in tonic and burst mode in 46 patients contralateral to the tinnitus side, at 5, 10 and 20 Hz. Fourteen placebo negative rTMS responders are further analyzed. RESULTS In 5 patients, maximal tinnitus suppression is obtained with theta, in 2 with alpha and in 7 with beta burst stimulation. Burst rTMS suppresses narrow band/white tinnitus much better than tonic rTMS t(13)=6.4, p<.000. Women experience greater suppression of their tinnitus with burst stimulation than men, t(12)=2.9, p<.05. Furthermore left sided tinnitus is perceived as more distressing on the TQ than right sided tinnitus, t(12)=3.2, p<.01. The lower the tinnitus pitch the more effectively rTMS suppresses tinnitus(r=-0.65, p<0.05). DISCUSSION Burst rTMS can be used clinically, not only theta burst, but also alpha and beta burst. Burst rTMS is capable of suppressing narrow band/white noise tinnitus very much better than tonic rTMS. This could be due the simple fact that burst neuromodulation is more powerful than tonic neuromodulation or to a differential effect of burst and tonic stimulation on the lemniscal and extralemniscal auditory system. In some patients only alpha or beta burst rTMS is capable of suppressing tinnitus, and theta burst not. Therefore in future rTMS studies it could be worthwhile not to limit burst stimulation to theta burst rTMS.
Collapse
Affiliation(s)
- Dirk De Ridder
- Dept of Neurosurgery, ENT, University Hospital Antwerp, Edegem, Belgium.
| | | | | | | | | | | |
Collapse
|
38
|
De Ridder D, van der Loo E, Van der Kelen K, Menovsky T, van de Heyning P, Moller A. Do tonic and burst TMS modulate the lemniscal and extralemniscal system differentially? Int J Med Sci 2007; 4:242-6. [PMID: 17952200 PMCID: PMC2016869 DOI: 10.7150/ijms.4.242] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/22/2007] [Accepted: 10/08/2007] [Indexed: 11/11/2022] Open
Abstract
INTRODUCTION Tinnitus is an auditory phantom percept related to tonic and burst hyperactivity of the auditory system. Two parallel pathways supply auditory information to the cerebral cortex: the tonotopically organised lemniscal system, and the non-tonotopic extralemniscal system, firing in tonic mode and burst mode respectively. Transcranial magnetic stimulation (TMS) is a non-invasive method capable of modulating activity of the human cortex, by delivering tonic or burst stimuli. Burst stimulation is shown to be more powerful in activating the cerebral cortex than tonic stimulation and bursts may activate neurons that are not activated by tonic stimulations. METHODS The effect of both tonic and burst TMS in 14 placebo-negative patients presenting narrow band/white noise tinnitus were analysed. RESULTS Our TMS results show that narrow band/white noise tinnitus is better suppressed with burst TMS in comparison to tonic TMS, t(13)=6.4, p=.000. For pure tone tinnitus no difference is found between burst or tonic TMS, t(13)=.3, ns. DISCUSSION Based on the hypothesis that white noise is the result of hyperactivity in the non-tonotopic system and pure tone tinnitus of the tonotopic system, we suggest that burst stimulation modulates the extralemniscal system and lemniscal system and tonic stimulation only the lemniscal system.
Collapse
Affiliation(s)
- Dirk De Ridder
- Dept of Neurosurgery, ENT, University Hospital Antwerp, Edegem, Belgium.
| | | | | | | | | | | |
Collapse
|
39
|
Saeb S, Gharibzadeh S, Towhidkhah F, Farajidavar A. Modeling the primary auditory cortex using dynamic synapses: can synaptic plasticity explain the temporal tuning? J Theor Biol 2007; 248:1-9. [PMID: 17559885 DOI: 10.1016/j.jtbi.2007.03.025] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2006] [Revised: 03/20/2007] [Accepted: 03/20/2007] [Indexed: 11/17/2022]
Abstract
The molecular mechanisms underlying the temporal plasticity (temporal tuning) of cortical cells remain controversial. Experimental observations indicate that the neuronal responses at the primary auditory cortex are affected by behavioral learning. In this paper, we present a minimal feed-forward model of the primary auditory cortex, based on the dynamic synapse and the leaky integrate-and-fire neuron models, in order to search for the origin of the observed plasticity. We demonstrate that the frequency response of the model is markedly modified by regulating the contribution of synaptic facilitation to the short-term dynamics of synapses (U(1)). Consequently, we propose that the variation of this parameter may be responsible for primary auditory cortex enhancement achieved by behavioral training. Based on our model, we assume that the contribution of facilitation arises from the amount of Ca(2+) influx each time an action potential arrives at the nerve terminal. Regardless of what really leads to the long-term variation of Ca(2+) influx, we suggest that this process is responsible for the temporal tuning of responses observed in experimental studies. We believe that measurement of the long-term variation of Ca(2+) influx at the pre-synaptic area of the cortical cells in auditory learning trials would be the first step to validate our hypothesis.
Collapse
Affiliation(s)
- Sohrab Saeb
- Cognitive Neural Engineering Lab, Faculty of Biomedical Engineering, Amirkabir University of Technology (Tehran Polytechnic), Tehran, Iran
| | | | | | | |
Collapse
|
40
|
Bartlett EL, Wang X. Neural Representations of Temporally Modulated Signals in the Auditory Thalamus of Awake Primates. J Neurophysiol 2007; 97:1005-17. [PMID: 17050830 DOI: 10.1152/jn.00593.2006] [Citation(s) in RCA: 89] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
In sensory systems, the thalamus has historically been considered a relay station. Neural representations of temporal modulations in the auditory system undergo considerable changes as they pass from the inferior colliculus (IC) to the auditory cortex. We sought to determine in awake primates the extent to which auditory thalamic neurons contribute to these transformations. We tested the temporal processing capabilities of medial geniculate body (MGB) neurons in awake marmoset monkeys using repetitive click stimuli. MGB neurons were able to synchronize to periodic clicks at repetition rates significantly higher than auditory cortex neurons. Unlike responses in the MGB of anesthetized animals, >40% of MGB neurons in awake marmosets displayed nonsynchronized discharges when stimulated by high click rates (short interclick intervals). Such nonsynchronized MGB responses typically occurred at higher repetition rates than those observed in auditory cortex. In contrast to auditory cortex neurons, many MGB neurons exhibited both synchronized and nonsynchronized discharge patterns. In both MGB and auditory cortex, synchronized and nonsynchronized responses represented complementary ranges of interclick intervals (1/click rate). Furthermore, the temporal processing abilities of some MGB neurons were sensitive to the spectrotemporal parameters of the click stimuli used. Together, these findings suggest that MGB neurons participate in active transformations of the neural representations of temporal modulations from IC to auditory cortex. In particular, the MGB appears to be the first station in the auditory ascending pathway in which substantial nonsynchronized responses emerge.
Collapse
Affiliation(s)
- Edward L Bartlett
- Dept. of Biomedical Engineering, Traylor 412, Johns Hopkins University, 720 Rutland Avenue, Baltimore, MD 21205, USA.
| | | |
Collapse
|
41
|
Komura Y, Tamura R, Uwano T, Nishijo H, Ono T. Auditory thalamus integrates visual inputs into behavioral gains. Nat Neurosci 2005; 8:1203-9. [PMID: 16116444 DOI: 10.1038/nn1528] [Citation(s) in RCA: 88] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2005] [Accepted: 07/28/2005] [Indexed: 11/09/2022]
Abstract
By binding multisensory signals, we get robust percepts and respond to our surroundings more correctly and quickly. How and where does the brain link cross-modal sensory information to produce such behavioral advantages? The classical role of sensory thalamus is to relay modality-specific information to the cortex. Here we find that, in the rat thalamus, visual cues influence auditory responses, which have two distinct components: an early phasic one followed by a late gradual buildup that peaks before reward. Although both bimodal presentation and reward value had similar effects on behavioral performance, the cross-modal effect on neural activity showed unique temporal dynamics: it affected the amplitude of the early component and starting level of the late component, whereas reward value affected only the slope of the late component. These results demonstrate that cross-modal cueing modulates gain in the sensory thalamus, potentially providing a priming influence on the choice of an optimal behavior.
Collapse
Affiliation(s)
- Yutaka Komura
- Neuroscience Research Institute, National Institute of Advanced Industrial Science and Technology, 1-1-1 Umezono, Tsukuba 305-8568, Japan
| | | | | | | | | |
Collapse
|
42
|
Hu B, Mooney DM. Burst firing induces a slow after hyperpolarization in rat auditory thalamus. Neurosci Lett 2005; 375:162-4. [PMID: 15694252 DOI: 10.1016/j.neulet.2004.11.005] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2004] [Revised: 11/02/2004] [Accepted: 11/02/2004] [Indexed: 11/25/2022]
Abstract
The Ca2+-activated slow after hyperpolarization (sAHP) is found in many CNS regions where it may induce post-spike suppression of neuronal firing over many seconds. Nevertheless, the presence of sAHP in sensory thalamus remains uncertain. Here we show that a robust sAHP could be evoked in the rat medial geniculate body of auditory thalamus in vitro following a low-threshold Ca2+ spike and burst firing. The evoked sAHP exhibited kinetic and pharmacological features similar to that found elsewhere in the CNS. The sAHP was resistant to TTX or apamin but eliminated by muscarine. Furthermore, activation of low-threshold Ca2+ conductance alone is sufficient to induce the sAHP. Therefore, the membrane conductance underlying sAHP is functionally expressed in lemniscal thalamic relay neurons which may be preferably activated during burst firing.
Collapse
Affiliation(s)
- B Hu
- Department of Clinical Neurosciences and Calgary Brain Institute, HMR Building, Room 170, Faculty of Medicine, University of Calgary, 3330 Hospital Drive N.W., Calgary, Alta., Canada T2N 4N1.
| | | |
Collapse
|
43
|
Cruz NF, Lasater A, Zielke HR, Dienel GA. Activation of astrocytes in brain of conscious rats during acoustic stimulation: acetate utilization in working brain. J Neurochem 2005; 92:934-47. [PMID: 15686496 DOI: 10.1111/j.1471-4159.2004.02935.x] [Citation(s) in RCA: 80] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
To evaluate the response of astrocytes in the auditory pathway to increased neuronal signaling elicited by acoustic stimulation, conscious rats were presented with a unilateral broadband click stimulus and functional activation was assessed by quantitative autoradiography using three tracers to pulse label different metabolic pools in brain: [2-14C]acetate labels the 'small' (astrocytic) glutamate pool, [1-14C]hydroxybutyrate labels the 'large' glutamate pool, and [14C]deoxyglucose, reflects overall glucose utilization (CMR(glc)) in all brain cells. CMR(glc) rose during brain activation, and increased activity of the oxidative pathway in working astrocytes during acoustic stimulation was registered with [2-14C]acetate. In contrast, the stimulation-induced increase in metabolic activity was not reflected by greater trapping of products of [1-14C]hydroxybutyrate. The [2-14C]acetate uptake coefficient in the inferior colliculus and lateral lemniscus during acoustic stimulation was 15% and 18% (p < 0.01) higher in the activated compared to contralateral hemisphere, whereas CMR(glc) in these structures rose by 66% (p < 0.01) and 42% (p < 0.05), respectively. Calculated rates of brain utilization of blood-borne acetate (CMR(acetate)) are about 15-25% of total CMR(glc) in non-stimulated tissue and 10-20% of CMR(glc) in acoustically activated structures; they range from 28 to 115% of estimated rates of glucose oxidation in astrocytes. The rise in acetate utilization during acoustic stimulation is modest compared to total CMR(glc), but astrocytic oxidative metabolism of 'minor' substrates present in blood can make a significant contribution to the overall energetics of astrocytes and astrocyte-neuron interactions in working brain.
Collapse
Affiliation(s)
- Nancy F Cruz
- Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, AR 72205, USA
| | | | | | | |
Collapse
|
44
|
Yu YQ, Xiong Y, Chan YS, He J. In vivo intracellular responses of the medial geniculate neurones to acoustic stimuli in anaesthetized guinea pigs. J Physiol 2004; 560:191-205. [PMID: 15272038 PMCID: PMC1665209 DOI: 10.1113/jphysiol.2004.067678] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2004] [Accepted: 07/21/2004] [Indexed: 11/08/2022] Open
Abstract
In the present study, we investigated the auditory response features of the medial geniculate neurones, using in vivo intracellular recordings in anaesthetized guinea pigs. Of the 76 neurones examined, 9 showed 'off' or 'on-off' responses to an acoustic stimulus and thus were defined as 'off' or 'on-off' neurones. Among the remaining 67 neurones, 42 showed an excitatory postsynaptic potential (EPSP) to acoustic stimuli and 25 showed either a pure inhibitory postsynaptic potential (IPSP, 7 neurones), or an IPSP preceded by an EPSP (EPSP-IPSP type, 18 neurones). The EPSP responses exhibited a mean latency of 15.7 +/- 6.1 ms, which was significantly shorter than that of the IPSP responses (21.3 +/- 8.6 ms, P < 0.01). The IPSP responses also showed a significantly greater duration than the EPSP responses (208.5 +/- 128.2 ms versus 122.4 +/- 84.8 ms, P < 0.05), while there were no significant differences between the amplitudes of IPSP and EPSP (8.3 +/- 3.2 mV versus 8.7 +/- 5.3 mV). Of the 11 neurones that showed EPSP responses to acoustic stimuli and were histologically labelled, 7 were located in the lemniscal medial geniculate body (MGB) and 4 in the non-lemniscal MGB. Another 6 labelled neurones that showed IPSP responses to acoustic stimuli were located in the non-lemniscal MGB. With a membrane potential of above -72 mV, the neurones showed greater EPSP or IPSP to an acoustic stimulus when their membrane potential was depolarized. However, upon hyperpolarization to below -74 mV, the neurones shifted to low-threshold calcium spikes (LTS)/LTS bursts. In response to auditory stimuli of different durations, 'off' neurones that responded to the offset of the acoustic stimulus and were located in the non-lemniscal MGB showed different response latencies or deviations of latencies in addition to exhibiting different numbers of spikes, suggesting that the timing of the spikes could be another component utilized by thalamic neurones to encode information on the stimulus. Given that some non-lemniscal neurones are multisensory and project to the entire auditory cortex, the selective corticofugal inhibition in the non-lemniscal MGB would enable the ascending pathway to prepare the auditory cortex to receive subsequent auditory information, avoiding the interference of other sensory inputs.
Collapse
Affiliation(s)
- Yan-Qin Yu
- Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | | | | | | |
Collapse
|
45
|
Massaux A, Dutrieux G, Cotillon-Williams N, Manunta Y, Edeline JM. Auditory Thalamus Bursts in Anesthetized and Non-Anesthetized States: Contribution to Functional Properties. J Neurophysiol 2004; 91:2117-34. [PMID: 14724263 DOI: 10.1152/jn.00970.2003] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Over the last 10 years, high-frequency bursts of action potentials have been the subject of intense researches to understand their potential role in information encoding. Based on recordings from auditory thalamus neurons ( n = 302) collected during anesthesia (pentobarbital, urethan, or ketamine/xylazine), waking (W), and slow-wave sleep (SWS), we investigated how bursts participate to frequency tuning, intensity-function, response latency (and latency variability), and stimulus detectability. Although present in all experimental conditions, bursts never dominated the cells mode of discharge: the highest proportion was found during ketamine/xylazine anesthesia (22%), the lowest during waking (4.5%). In all experimental conditions, bursts preferentially occurred at or around the cells best frequency (BF), thus increasing the frequency selectivity. This effect was observed at both the intensities producing the highest and the lowest evoked responses. Testing the intensity-functions indicated that for most of the cells, there was no systematic relationship between burst proportion and responses strength. Under several conditions (W, SWS, and urethan), when cells exhibited bursts >20%, the variability of their response latency was reduced in burst mode compared with single-spike mode. During W, this effect was accompanied by a reduction of the response latency. Finally, a receiver operating characteristic analysis indicated no particular relation between bursts and stimulus detectability. Compared with single-spike mode, which is present for broader frequency ranges, the prominence of bursts at the BF should contribute to filter information reaching the targets of medial geniculate cells at both cortical and subcortical levels.
Collapse
Affiliation(s)
- A Massaux
- Laboratoire de Neurobiologie de l'Apprentissage, de la Mémoire et de la Communication, Unité Mixte de Recherche, Centre National de la Recherche Scientifique 8620, Université Paris-Sud, Orsay, France
| | | | | | | | | |
Collapse
|
46
|
Mooney DM, Zhang L, Basile C, Senatorov VV, Ngsee J, Omar A, Hu B. Distinct forms of cholinergic modulation in parallel thalamic sensory pathways. Proc Natl Acad Sci U S A 2003; 101:320-4. [PMID: 14691260 PMCID: PMC314183 DOI: 10.1073/pnas.0304445101] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Mammalian thalamus is a critical site where early perception of sensorimotor signals is dynamically regulated by acetylcholine in a behavioral state-dependent manner. In this study, we examined how synaptic transmission is modulated by acetylcholine in auditory thalamus where sensory relay neurons form parallel lemniscal and nonlemniscal pathways. The former mediates tonotopic relay of acoustic signals, whereas the latter is involved in detecting and transmitting auditory cues of behavioral relevance. We report here that activation of cholinergic muscarinic receptors had opposite membrane effects on these parallel synaptic pathways. In lemniscal neurons, muscarine induced a sustained membrane depolarization and tonic firing by closing a linear K(+) conductance. In contrast, in nonlemniscal neurons, muscarine evoked a membrane hyperpolarization by opening a voltage-independent K(+) conductance. Depending on the level of membrane hyperpolarization and the strength of local synaptic input, nonlemniscal neurons were either suppressed or selectively engaged in detecting and transmitting synchronized synaptic input by firing a high-frequency spike burst. Immunohistochemical and Western blotting experiments showed that nonlemniscal neurons predominantly expressed M2 muscarinic receptors, whereas lemniscal cells had a significantly higher level of M1 receptors. Our data indicate that cholinergic modulation in the thalamus is pathway-specific. Enhanced cholinergic tone during behavioral arousal or attention may render synaptic transmission in nonlemniscal thalamus highly sensitive to the context of local synaptic activities.
Collapse
Affiliation(s)
- D M Mooney
- Ottawa Health Research Institute and University of Ottawa, Ottawa, ON, Canada K1Y 4E9
| | | | | | | | | | | | | |
Collapse
|
47
|
Massaux A, Edeline JM. Bursts in the medial geniculate body: a comparison between anesthetized and unanesthetized states in guinea pig. Exp Brain Res 2003; 153:573-8. [PMID: 12898102 DOI: 10.1007/s00221-003-1516-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2002] [Accepted: 04/16/2003] [Indexed: 10/26/2022]
Abstract
Thalamic high frequency bursts have long been described under anesthesia and during slow-wave sleep (SWS). More recently, studies in the lateral geniculate nucleus have pointed out that they are also present during waking (W). Here, we compared the bursts recorded in the medial geniculate body of guinea pigs under anesthesia or during periods of W and SWS. The tuning of single units was tested between threshold and 80 dB SPL in two conditions: (1) in restrained, undrugged, non-sleep-deprived guinea pigs (n=101 cells) and (2) under pentobarbital anesthesia (n=53 cells). Off-line analyses allowed us to distinguish single action potentials (APs) from bursts. A burst was defined as a group of APs with an interspike interval < or =4 ms, preceded by a silent period > or =100 ms. We found that auditory thalamus bursts occur in synchronized electroencephalogram states (SWS and anesthesia), but also during W. Although the burst characteristics did not differ among the three states, group data showed that the proportion of bursts within spike trains was the greatest under anesthesia. This observation resulted from two types of effects: (1) the percentage of non-bursting cells was lowest under anesthesia and (2) some cells under anesthesia exhibited up to 90% of bursts, whereas during W or SWS the highest proportion of bursts did not exceed 40%. The presence of these bursts is discussed with regards to the known fluctuations of membrane potential which occur in these various states.
Collapse
Affiliation(s)
- Aurélie Massaux
- Laboratoire de Neurobiologie de l'Apprentissage de la Mémoire et de la Communication, CNRS UMR 8620, Université Paris-Sud, Bât 446, 91405 Orsay, France
| | | |
Collapse
|
48
|
Hu B. Functional organization of lemniscal and nonlemniscal auditory thalamus. Exp Brain Res 2003; 153:543-9. [PMID: 12937877 DOI: 10.1007/s00221-003-1611-5] [Citation(s) in RCA: 86] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2002] [Accepted: 06/14/2003] [Indexed: 12/19/2022]
Abstract
Thalamic nuclei of the mammalian auditory system exhibit remarkable parallelism in their anatomical pathways and the patterns of synaptic signalling. This has led to the theory that lemniscal, or core thalamocortical projection, carries tonotopically organized and auditory specific information whereas the nonlemniscal thalamocortical pathway forms part of an integrative system that plays an important role in polysensory integration, temporal pattern recognition, and certain forms of learning. Recent experimental evidence derived from molecular, cellular and behavioural studies indeed supports the conjecture that lemniscal and nonlemniscal pathways are involved in distinctive auditory functions.
Collapse
Affiliation(s)
- B Hu
- Department of Clinical Neurosciences and Neuroscience Research Group, University of Calgary, 3330 Hospital Drive NW, Calgary, Alberta, T2N 4N1, Canada.
| |
Collapse
|
49
|
Abstract
In the present study, we investigated the oscillatory behavior of the auditory thalamic neurons through in vivo intracellular and extracellular recordings in anesthetized guinea pigs. Repeated acoustic stimulus and cortical electrical stimulation were applied to examine their modulatory effects on the thalamic oscillation. The time course of the spike frequency over each trial was obtained by summing all spikes in the onset period and/or the last time period of 100 or 200 msec in the raster display. Spectral analysis was made on the time course of the spike frequency. A slow-frequency oscillation ranging from 0.03 to 0.25 Hz (mean +/- SD, 0.11 +/- 0.05 Hz) was found in the medial geniculate body (MGB) together with a second rhythm of 5-10 Hz. The oscillation neurons had a mean auditory response latency of 17.3 +/- 0.3 msec, which was significantly longer than that of the non-oscillation neurons in lemniscal MGB (9.0 +/- 1.5 msec, p < 0.001, ANOVA) and similar to the non-oscillation neurons in the non-lemniscal MGB (17.6 +/- 5.4 msec, p = 0.811). They were located in the non-lemniscal nuclei of the auditory thalamus. Cortical stimulation altered the thalamic oscillation, leading to termination of the oscillation or to acceleration of the rhythm of the oscillation (the average rhythm changed from 0.07 +/- 0.03 to 0.11 +/- 0.04 Hz, n = 8, p = 0.066, t test). Acoustic stimulation triggered a more regular rhythm in the oscillation neurons. The present results suggest that only the non-lemniscal auditory thalamus is involved in the slow thalamocortical oscillation. The auditory cortex may control the oscillation of the auditory thalamic neurons.
Collapse
|
50
|
He J. Slow oscillation in non-lemniscal auditory thalamus. J Neurosci 2003; 23:8281-90. [PMID: 12967990 PMCID: PMC6740700] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/04/2023] Open
Abstract
In the present study, we investigated the oscillatory behavior of the auditory thalamic neurons through in vivo intracellular and extracellular recordings in anesthetized guinea pigs. Repeated acoustic stimulus and cortical electrical stimulation were applied to examine their modulatory effects on the thalamic oscillation. The time course of the spike frequency over each trial was obtained by summing all spikes in the onset period and/or the last time period of 100 or 200 msec in the raster display. Spectral analysis was made on the time course of the spike frequency. A slow-frequency oscillation ranging from 0.03 to 0.25 Hz (mean +/- SD, 0.11 +/- 0.05 Hz) was found in the medial geniculate body (MGB) together with a second rhythm of 5-10 Hz. The oscillation neurons had a mean auditory response latency of 17.3 +/- 0.3 msec, which was significantly longer than that of the non-oscillation neurons in lemniscal MGB (9.0 +/- 1.5 msec, p < 0.001, ANOVA) and similar to the non-oscillation neurons in the non-lemniscal MGB (17.6 +/- 5.4 msec, p = 0.811). They were located in the non-lemniscal nuclei of the auditory thalamus. Cortical stimulation altered the thalamic oscillation, leading to termination of the oscillation or to acceleration of the rhythm of the oscillation (the average rhythm changed from 0.07 +/- 0.03 to 0.11 +/- 0.04 Hz, n = 8, p = 0.066, t test). Acoustic stimulation triggered a more regular rhythm in the oscillation neurons. The present results suggest that only the non-lemniscal auditory thalamus is involved in the slow thalamocortical oscillation. The auditory cortex may control the oscillation of the auditory thalamic neurons.
Collapse
Affiliation(s)
- Jufang He
- Department of Rehabilitation Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China.
| |
Collapse
|