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Merlino L, Titi L, Pugliese F, D’Ovidio G, Senatori R, Rocca CD, Piccioni MG. Vulvodynia: Pain Management Strategies. Pharmaceuticals (Basel) 2022; 15:ph15121514. [PMID: 36558965 PMCID: PMC9781267 DOI: 10.3390/ph15121514] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2022] [Revised: 11/29/2022] [Accepted: 12/02/2022] [Indexed: 12/12/2022] Open
Abstract
Background: Vulvodynia is defined in this international consensus as persistent vulvar pain that occurs for >3 months without an identifiable cause and with several potential associated factors. At present there is no univocal consensus in the therapeutic treatment of vulvodynia. The methods of intervention are based on various aspects including, above all, the management of painful symptoms. Methods: a research on scientific database such as “Pubmed”, “Medline Plus”, “Medscape” was conducted, using the words “women’s genital pain” and “vulvodynia” for the review of the scientific evidence on the assessment and treatment of women’s genital pain. Results: Among the drugs with pain-relieving action, the most effective in the treatment of vulvodynia would seem to be those with antidepressant and anticonvulsant action, even if their mechanisms of action are not known and there are still insufficient studies able to demonstrate their real validity. Among the least effective are non-steroidal anti-inflammatory drugs (NSAIDs) and corticosteroids. However, the ideal would seem to use a combined treatment with multiple types of drugs. Conclusions: Future studies are needed to draw up a unique therapeutic action plan that considers the stratification of patients with vulvodynia and the variability of the symptom.
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Affiliation(s)
- Lucia Merlino
- Department of Maternal Infantile and Urological Sciences, Sapienza University of Rome, 00161 Rome, Italy
- Correspondence:
| | - Luca Titi
- Department of Anesthesia and Intensive Care Medicine, Sapienza University of Rome, 00161 Rome, Italy
| | - Francesco Pugliese
- Department of Anesthesia and Intensive Care Medicine, Sapienza University of Rome, 00161 Rome, Italy
| | - Giulia D’Ovidio
- Department of Maternal Infantile and Urological Sciences, Sapienza University of Rome, 00161 Rome, Italy
| | - Roberto Senatori
- Italian Society of Colposcopy and Cervicovaginal Pathology (SICPV), 00186 Rome, Italy
| | - Carlo Della Rocca
- Department of Medical-Surgical Sciences and Biotechnologies, Sapienza University of Rome, 00161 Rome, Italy
| | - Maria Grazia Piccioni
- Department of Maternal Infantile and Urological Sciences, Sapienza University of Rome, 00161 Rome, Italy
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Domanski APF, Booker SA, Wyllie DJA, Isaac JTR, Kind PC. Cellular and synaptic phenotypes lead to disrupted information processing in Fmr1-KO mouse layer 4 barrel cortex. Nat Commun 2019; 10:4814. [PMID: 31645553 PMCID: PMC6811545 DOI: 10.1038/s41467-019-12736-y] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Accepted: 09/23/2019] [Indexed: 02/06/2023] Open
Abstract
Sensory hypersensitivity is a common and debilitating feature of neurodevelopmental disorders such as Fragile X Syndrome (FXS). How developmental changes in neuronal function culminate in network dysfunction that underlies sensory hypersensitivities is unknown. By systematically studying cellular and synaptic properties of layer 4 neurons combined with cellular and network simulations, we explored how the array of phenotypes in Fmr1-knockout (KO) mice produce circuit pathology during development. We show that many of the cellular and synaptic pathologies in Fmr1-KO mice are antagonistic, mitigating circuit dysfunction, and hence may be compensatory to the primary pathology. Overall, the layer 4 network in the Fmr1-KO exhibits significant alterations in spike output in response to thalamocortical input and distorted sensory encoding. This developmental loss of layer 4 sensory encoding precision would contribute to subsequent developmental alterations in layer 4-to-layer 2/3 connectivity and plasticity observed in Fmr1-KO mice, and circuit dysfunction underlying sensory hypersensitivity.
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Affiliation(s)
- Aleksander P F Domanski
- School of Physiology, Pharmacology & Neuroscience, University of Bristol, Bristol, UK.
- Centre for Discovery Brain Sciences, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK.
- Patrick Wild Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK.
- Developmental Synaptic Plasticity Section, NINDS, NIH, Bethesda, MD, 20892, USA.
| | - Sam A Booker
- Centre for Discovery Brain Sciences, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
- Patrick Wild Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
- Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
| | - David J A Wyllie
- Centre for Discovery Brain Sciences, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
- Patrick Wild Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
- Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK
- Centre for Brain Development and Repair, NCBS, GKVK Campus, Bangalore, 560065, India
| | - John T R Isaac
- Developmental Synaptic Plasticity Section, NINDS, NIH, Bethesda, MD, 20892, USA.
- Janssen Neuroscience, J&J London Innovation Centre, J&J London Innovation Centre, One Chapel Place, London, W1G 0B, UK.
| | - Peter C Kind
- Centre for Discovery Brain Sciences, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK.
- Patrick Wild Centre, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK.
- Simons Initiative for the Developing Brain, University of Edinburgh, Hugh Robson Building, George Square, Edinburgh, EH8 9XD, UK.
- Centre for Brain Development and Repair, NCBS, GKVK Campus, Bangalore, 560065, India.
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Cortical Visual Performance Test Setup for Parkinson's Disease Based on Motion Blur Orientation. PARKINSONS DISEASE 2019; 2019:3247608. [PMID: 30854187 PMCID: PMC6377996 DOI: 10.1155/2019/3247608] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 12/14/2018] [Accepted: 12/25/2018] [Indexed: 11/18/2022]
Abstract
Studies on Parkinson's disease (PD) are becoming very popular on multidisciplinary platforms. The development of predictable telemonitored early detection models has become closely related to many different research areas. The aim of this article is to develop a visual performance test that can examine the effects of Parkinson's disease on the visual cortex, which can be a subtitle scoring test in UPDRS. However, instead of showing random images and asking for discrepancies between them, it is expected that the questions to be asked to patients should be provable in the existing cortex models, should be deduced between the images, and produce a reference threshold value to compare with the practical results. In a developed test, horizontal and vertical motion blur orientation was applied to natural image samples, and then neural outputs were produced by representing three (original-horizontal-vertical) image groups with the Layer 4 (L4) cortex model. This image representation is then compared with a filtering model which is very similar to thalamus' functionality. Thus, the linear problem-solving performance of the L4 cortex model is also addressed in the study. According to the obtained classification results, the L4 model produces high-performance success rates compared to the thalamic model, which shows the adaptation power of the visual cortex on the image pattern differences. In future studies, developed motion-based visual tests are planned to be applied to PD patient groups/controls, and their performances with mathematical threshold values will be examined.
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The Role of Attention in Somatosensory Processing: A Multi-trait, Multi-method Analysis. J Autism Dev Disord 2017; 46:3232-41. [PMID: 27448580 DOI: 10.1007/s10803-016-2866-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Sensory processing abnormalities in autism have largely been described by parent report. This study used a multi-method (parent-report and measurement), multi-trait (tactile sensitivity and attention) design to evaluate somatosensory processing in ASD. Results showed multiple significant within-method (e.g., parent report of different traits)/cross-trait (e.g., attention and tactile sensitivity) correlations, suggesting that parent-reported tactile sensory dysfunction and performance-based tactile sensitivity describe different behavioral phenomena. Additionally, both parent-reported tactile functioning and performance-based tactile sensitivity measures were significantly associated with measures of attention. Findings suggest that sensory (tactile) processing abnormalities in ASD are multifaceted, and may partially reflect a more global deficit in behavioral regulation (including attention). Challenges of relying solely on parent-report to describe sensory difficulties faced by children/families with ASD are also highlighted.
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Favorov OV, Kursun O, Tommerdahl M. Role of Feed-Forward Inhibition in Neocortical Information Processing: Implications for Neurological Disorders. THE PHYSICS OF THE MIND AND BRAIN DISORDERS 2017. [DOI: 10.1007/978-3-319-29674-6_17] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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Puts NAJ, Wodka EL, Harris AD, Crocetti D, Tommerdahl M, Mostofsky SH, Edden RAE. Reduced GABA and altered somatosensory function in children with autism spectrum disorder. Autism Res 2016; 10:608-619. [PMID: 27611990 DOI: 10.1002/aur.1691] [Citation(s) in RCA: 142] [Impact Index Per Article: 17.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2016] [Revised: 07/22/2016] [Accepted: 08/12/2016] [Indexed: 11/11/2022]
Abstract
BACKGROUND Abnormal responses to tactile stimuli are a common feature of autism spectrum disorder (ASD). Several lines of evidence suggest that GABAergic function, which has a crucial role in tactile processing, is altered in ASD. In this study, we determine whether in vivo GABA levels are altered in children with ASD, and whether alterations in GABA levels are associated with abnormal tactile function in these children. METHODS GABA-edited magnetic resonance spectroscopy was acquired in 37 children with Autism and 35 typically developing children (TDC) from voxels over primary sensorimotor and occipital cortices. Children performed tactile tasks previously shown to be altered in ASD, linked to inhibitory mechanisms. Detection threshold was measured with- and without the presence of a slowly increasing sub-threshold stimulus. Amplitude discrimination was measured with- and without the presence of an adapting stimulus, and frequency discrimination was measured. RESULTS Sensorimotor GABA levels were significantly reduced in children with autism compared to healthy controls. Occipital GABA levels were normal. Sensorimotor GABA levels correlated with dynamic detection threshold as well as with the effect of sub-threshold stimulation. Sensorimotor GABA levels also correlated with amplitude discrimination after adaptation (an effect absent in autism) and frequency discrimination in controls, but not in children with autism. CONCLUSIONS GABA levels correlate with behavioral measures of inhibition. Children with autism have reduced GABA, associated with abnormalities in tactile performance. We show here that altered in vivo GABA levels might predict abnormal tactile information processing in ASD and that the GABA system may be a future target for therapies. Autism Res 2016. © 2016 International Society for Autism Research, Wiley Periodicals, Inc.
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Affiliation(s)
- Nicolaas A J Puts
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, 600 N Wolfe Street, Baltimore, Maryland, 21287.,F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, 707 N Broadway Street, Baltimore, Maryland, 21205
| | - Ericka L Wodka
- Center for Neurocognitive and Imaging Research, Kennedy Krieger Institute, 716 N Broadway, Baltimore, Maryland, 21205.,Center for Autism and Related Disorders, Kennedy Krieger Institute, 3901 Greenspring Ave, Baltimore, Maryland, 21211.,Department of Behavioral Science and Psychiatry, Johns Hopkins University, School of Medicine, 600 N Wolfe Street, Baltimore, Maryland, 21287
| | - Ashley D Harris
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, 600 N Wolfe Street, Baltimore, Maryland, 21287.,F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, 707 N Broadway Street, Baltimore, Maryland, 21205.,Radiology, University of Calgary, 1403 - 29th Street N.W, Calgary, AB, T2N 2T9, Canada.,CAIR Program, Alberta Children's Hospital Research Institute, University of Calgary, 1403 - 29th Street N.W, Calgary, AB, T2N 2T9, Canada.,Hotchkiss Brain Institute and Alberta Children's Hospital Research Institute, 3330 Hospital Drive NW, Calgary, AB, T2N 4N1, Canada
| | - Deana Crocetti
- F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, 707 N Broadway Street, Baltimore, Maryland, 21205.,Center for Neurocognitive and Imaging Research, Kennedy Krieger Institute, 716 N Broadway, Baltimore, Maryland, 21205
| | - Mark Tommerdahl
- Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, 27599
| | - Stewart H Mostofsky
- Center for Neurocognitive and Imaging Research, Kennedy Krieger Institute, 716 N Broadway, Baltimore, Maryland, 21205.,Center for Autism and Related Disorders, Kennedy Krieger Institute, 3901 Greenspring Ave, Baltimore, Maryland, 21211.,Department of Neurology, Johns Hopkins School of Medicine, 600 N Wolfe Street, Baltimore, Maryland, 21287
| | - Richard A E Edden
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, 600 N Wolfe Street, Baltimore, Maryland, 21287.,F.M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, 707 N Broadway Street, Baltimore, Maryland, 21205
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Jin D, Peng J. Investigation on Amari’s dynamical neural field with global constant inhibition. Neural Netw 2015; 71:182-95. [DOI: 10.1016/j.neunet.2015.08.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2014] [Revised: 06/10/2015] [Accepted: 08/20/2015] [Indexed: 10/23/2022]
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Puts NAJ, Harris AD, Crocetti D, Nettles C, Singer HS, Tommerdahl M, Edden RAE, Mostofsky SH. Reduced GABAergic inhibition and abnormal sensory symptoms in children with Tourette syndrome. J Neurophysiol 2015; 114:808-17. [PMID: 26041822 PMCID: PMC4533064 DOI: 10.1152/jn.00060.2015] [Citation(s) in RCA: 91] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2015] [Accepted: 05/28/2015] [Indexed: 11/22/2022] Open
Abstract
Tourette Syndrome (TS) is characterized by the presence of chronic tics. Individuals with TS often report difficulty with ignoring (habituating to) tactile sensations, and some patients perceive that this contributes to a "premonitory urge" to tic. While common, the physiological basis of impaired tactile processing in TS, and indeed tics themselves, remain poorly understood. It has been well established that GABAergic processing plays an important role in shaping the neurophysiological response to tactile stimulation. Furthermore, there are multiple lines of evidence suggesting that a deficit in GABAergic transmission may contribute to symptoms found in TS. In this study, GABA-edited magnetic resonance spectroscopy (MRS) was combined with a battery of vibrotactile tasks to investigate the role of GABA and atypical sensory processing in children with TS. Our results show reduced primary sensorimotor cortex (SM1) GABA concentration in children with TS compared with healthy control subjects (HC), as well as patterns of impaired performance on tactile detection and adaptation tasks, consistent with altered GABAergic function. Moreover, in children with TS SM1 GABA concentration correlated with motor tic severity, linking the core feature of TS directly to in vivo brain neurochemistry. There was an absence of the typical correlation between GABA and frequency discrimination performance in TS as was seen in HC. These data show that reduced GABA concentration in TS may contribute to both motor tics and sensory impairments in children with TS. Understanding the mechanisms of altered sensory processing in TS may provide a foundation for novel interventions to alleviate these symptoms.
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Affiliation(s)
- Nicolaas A J Puts
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland; F. M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland;
| | - Ashley D Harris
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland; F. M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Deana Crocetti
- Center for Neurodevelopment and Imaging Research, Kennedy Krieger Institute, Baltimore, Maryland
| | - Carrie Nettles
- Center for Neurodevelopment and Imaging Research, Kennedy Krieger Institute, Baltimore, Maryland
| | - Harvey S Singer
- Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Mark Tommerdahl
- Department of Biomedical Engineering, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina
| | - Richard A E Edden
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland; F. M. Kirby Center for Functional Brain Imaging, Kennedy Krieger Institute, Baltimore, Maryland
| | - Stewart H Mostofsky
- Center for Neurodevelopment and Imaging Research, Kennedy Krieger Institute, Baltimore, Maryland; Department of Neurology, Johns Hopkins University School of Medicine, Baltimore, Maryland; Department of Psychiatry and Behavioral Sciences, Johns Hopkins University School of Medicine, Baltimore, Maryland; and
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Puts NAJ, Wodka EL, Tommerdahl M, Mostofsky SH, Edden RAE. Impaired tactile processing in children with autism spectrum disorder. J Neurophysiol 2014; 111:1803-11. [PMID: 24523518 DOI: 10.1152/jn.00890.2013] [Citation(s) in RCA: 144] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Impaired responses to tactile stimulation are a commonly reported symptom among children with autism spectrum disorder (ASD). Furthermore, impairments in filtering or habituation to tactile input have been described in ASD. This study measured different aspects of tactile processing to investigate atypical touch sensitivity in children with ASD, methodology that has not been previously used in this population. Sixty-seven typically developing children (TDC) and 32 children with ASD (ages 8-12) completed vibrotactile tasks assessing: reaction time (RT); static and dynamic detection threshold (DT); amplitude discrimination with and without single-site adaptation; frequency discrimination; and temporal order judgment (TOJ) with and without concurrent stimulation. Children with ASD showed raised static detection thresholds and an absence of the effect of a dynamically increasing subthreshold stimulus on static detection threshold. Children with ASD also showed poorer amplitude discrimination than TDC, as well as decreased adaptation. There were no significant differences in frequency discrimination or TOJ performance between the groups. Differences in the effect of dynamic stimulation on detection threshold suggest impaired feed-forward inhibition in autism, which may be linked to poor sensory filtering. Increased baseline amplitude discrimination thresholds in ASD suggest that lateral inhibitory connections are weaker in ASD, and an absence of the effect of adaptation suggests impaired modulation of lateral inhibitory connections in ASD, which may relate to aberrant habituation. These results suggest a functional deficit in the somatosensory inhibitory system in autism. Understanding the specific mechanisms underlying sensory symptoms in autism may allow for more specific therapeutic or drug targeting in the near future.
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Affiliation(s)
- Nicolaas A J Puts
- Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, Baltimore, Maryland
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ALPTEKIN AHMET, KURSUN OLCAY. MISS ONE OUT: A CROSS-VALIDATION METHOD UTILIZING INDUCED TEACHER NOISE. INT J PATTERN RECOGN 2013. [DOI: 10.1142/s0218001413510038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Leave-one-out (LOO) and its generalization, K-Fold, are among most well-known cross-validation methods, which divide the sample into many folds, each one of which is, in turn, left out for testing, while the other parts are used for training. In this study, as an extension of this idea, we propose a new cross-validation approach that we called miss-one-out (MOO) that mislabels the example(s) in each fold and keeps this fold in the training set as well, rather than leaving it out as LOO does. Then, MOO tests whether the trained classifier can correct the erroneous label of the training sample. In principle, having only one fold deliberately labeled incorrectly should have only a small effect on the classifier that uses this bad-fold along with K - 1 good folds and can be utilized as a generalization measure of the classifier. Experimental results on a number of benchmark datasets and three real bioinformatics dataset show that MOO can better estimate the test set accuracy of the classifier.
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Affiliation(s)
- AHMET ALPTEKIN
- The Scientific and Technological Research Council of Turkey (TUBITAK), Gebze, Kocaeli 41470, Turkey
- Department of Computer Engineering, Istanbul University, Avcilar, Istanbul 34320, Turkey
| | - OLCAY KURSUN
- Department of Computer Engineering, Istanbul University, Avcilar, Istanbul 34320, Turkey
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Shipp S, Adams RA, Friston KJ. Reflections on agranular architecture: predictive coding in the motor cortex. Trends Neurosci 2013; 36:706-16. [PMID: 24157198 PMCID: PMC3858810 DOI: 10.1016/j.tins.2013.09.004] [Citation(s) in RCA: 144] [Impact Index Per Article: 13.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2013] [Revised: 08/23/2013] [Accepted: 09/18/2013] [Indexed: 12/30/2022]
Abstract
Predictive coding explains the recursive hierarchical structure of cortical processes. Granular layer 4, which relays ascending cortical pathways, is absent from motor cortex. Perceptual inference results if ascending sensory data modify sensory predictions action, if spinal reflexes enact descending motor and/or proprioceptive predictions. Motor layer 4 regresses as motor predictions inherently require less modification.
The agranular architecture of motor cortex lacks a functional interpretation. Here, we consider a ‘predictive coding’ account of this unique feature based on asymmetries in hierarchical cortical connections. In sensory cortex, layer 4 (the granular layer) is the target of ascending pathways. We theorise that the operation of predictive coding in the motor system (a process termed ‘active inference’) provides a principled rationale for the apparent recession of the ascending pathway in motor cortex. The extension of this theory to interlaminar circuitry also accounts for a sub-class of ‘mirror neuron’ in motor cortex – whose activity is suppressed when observing an action –explaining how predictive coding can gate hierarchical processing to switch between perception and action.
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Affiliation(s)
- Stewart Shipp
- Department of Visual Neuroscience, UCL Institute of Ophthalmology, University College London, Bath Street, London, EC1V 9EL, UK.
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Puts NAJ, Edden RAE, Wodka EL, Mostofsky SH, Tommerdahl M. A vibrotactile behavioral battery for investigating somatosensory processing in children and adults. J Neurosci Methods 2013; 218:39-47. [PMID: 23660524 PMCID: PMC4106128 DOI: 10.1016/j.jneumeth.2013.04.012] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2013] [Revised: 04/15/2013] [Accepted: 04/17/2013] [Indexed: 11/27/2022]
Abstract
The cortical dynamics of somatosensory processing can be investigated using vibrotactile psychophysics. It has been suggested that different vibrotactile paradigms target different cortical mechanisms, and a number of recent studies have established links between somatosensory cortical function and measurable aspects of behavior. The relationship between cortical mechanisms and sensory function is particularly relevant with respect to developmental disorders in which altered inhibitory processing has been postulated, such as in ASD and ADHD. In this study, a vibrotactile battery consisting of nine tasks (incorporating reaction time, detection threshold, and amplitude- and frequency discrimination) was applied to a cohort of healthy adults and a cohort of typically developing children to assess the feasibility of such a vibrotactile battery in both cohorts, and the performance between children and adults was compared. These results showed that children and adults were both able to perform these tasks with a similar performance, although the children were slightly less sensitive in frequency discrimination. Performance within different task-groups clustered together in adults, providing further evidence that these tasks tap into different cortical mechanisms, which is also discussed. This clustering was not observed in children, which may be potentially indicative of development and a greater variability. In conclusion, in this study, we showed that both children and adults were able to perform an extensive vibrotactile battery, and we showed the feasibility of applying this battery to other (e.g., neurodevelopmental) cohorts to probe different cortical mechanisms.
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Affiliation(s)
- Nicolaas A J Puts
- Russell H. Morgan Department of Radiology and Radiological Science, The Johns Hopkins University School of Medicine, 600 North Wolfe Street, Baltimore, MD 21287, USA.
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Nguyen RH, Ford S, Calhoun AH, Holden JK, Gracely RH, Tommerdahl M. Neurosensory assessments of migraine. Brain Res 2013; 1498:50-8. [PMID: 23298830 DOI: 10.1016/j.brainres.2012.12.043] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2012] [Revised: 12/17/2012] [Accepted: 12/29/2012] [Indexed: 11/26/2022]
Abstract
Headache medicine is primarily dependent on patients' subjective reports of pain, which are assessed at diagnosis and throughout the duration of treatment. There is a need for an objective, quantitative biological measurement of headache pain severity. In this study, quantitative sensory testing (QST) was conducted via multi-site vibrotactile stimulation in patients with migraine. The purpose was to investigate the sensitivity of the method and to determine if the metrics obtained from migraineurs could be differentiated from controls. Metrics reflecting sensory percepts of baseline measures of stimulus amplitude discrimination, temporal order judgment, and duration discrimination were significantly different. Additional measures previously demonstrated to be sensitive to alterations in centrally-mediated information processing features such as adaptation and synchronization were also significantly different from control values. In contrast, reaction times and vibrotactile detection thresholds of migraineurs failed to differentiate them from controls, indicating that the results are not due to peripheral neuropathy or some other primary afferent mechanism. The long-term objective of the study is to develop methods that can improve diagnosis and enable more accurate assessments of treatment efficacy in migraine.
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Affiliation(s)
- R H Nguyen
- Department of Biomedical Engineering, University of North Carolina at Chapel Hill, USA
| | - S Ford
- Carolina Headache Institute, USA
| | | | - J K Holden
- Department of Biomedical Engineering, University of North Carolina at Chapel Hill, USA
| | - R H Gracely
- School of Dentistry, University of North Carolina at Chapel Hill, USA
| | - M Tommerdahl
- Department of Biomedical Engineering, University of North Carolina at Chapel Hill, USA.
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Abstract
OBJECTIVE To investigate the clinical correlates of central nervous system alterations among women with vulvodynia. Altered central sensitization has been linked to dysfunction in central nervous system-inhibitory pathways (e.g., γ-aminobutyric acidergic), and metrics of sensory adaptation, a centrally mediated process that is sensitive to this dysfunction, could potentially be used to identify women at risk of treatment failure using conventional approaches. METHODS Twelve women with vulvodynia and 20 age-matched controls participated in this study, which was conducted by sensory testing of the right hand's index and middle fingers. The following sensory precepts were assessed: (1) vibrotactile detection threshold; (2) amplitude discrimination capacity (defined as the ability to detect differences in intensity of simultaneously delivered stimuli to 2 fingers); and (3) a metric of adaptation (determined by the impact that applying conditioning stimuli have on amplitude discriminative capacity). RESULTS Participants did not differ on key demographic variables, vibrotactile detection threshold, and amplitude discrimination capacity. However, we found significant differences from controls in adaptation metrics in 1 subgroup of vulvodynia patients. Compared with healthy controls and women with a shorter history of pain [n=5; duration (y) = 3.4 ± 1.3], those with a longer history [n=7; duration (y) = 9.3 ± 1.4)] were found to be less likely to have adaptation metrics similar to control values. DISCUSSION Chronic pain is thought to lead to altered central sensitization, and adaptation is a centrally mediated process that is sensitive to this condition. This report suggests that similar alterations exist in a subgroup of vulvodynia patients.
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Zhang Z, Francisco EM, Holden JK, Dennis RG, Tommerdahl M. Somatosensory information processing in the aging population. Front Aging Neurosci 2011; 3:18. [PMID: 22163221 PMCID: PMC3233724 DOI: 10.3389/fnagi.2011.00018] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2011] [Accepted: 11/21/2011] [Indexed: 11/13/2022] Open
Abstract
While it is well known that skin physiology – and consequently sensitivity to peripheral stimuli – degrades with age, what is less appreciated is that centrally mediated mechanisms allow for maintenance of the same degree of functionality in processing these peripheral inputs and interacting with the external environment. In order to demonstrate this concept, we obtained observations of processing speed, sensitivity (thresholds), discriminative capacity, and adaptation metrics on subjects ranging in age from 18 to 70. The results indicate that although reaction speed and sensory thresholds change with age, discriminative capacity, and adaptation metrics do not. The significance of these findings is that similar metrics of adaptation have been demonstrated to change significantly when the central nervous system (CNS) is compromised. Such compromise has been demonstrated in subject populations with autism, chronic pain, acute NMDA receptor block, concussion, and with tactile–thermal interactions. If the metric of adaptation parallels cortical plasticity, the results of the current study suggest that the CNS in the aging population is still capable of plastic changes, and this cortical plasticity could be the mechanism that compensates for the degradations that are known to naturally occur with age. Thus, these quantitative measures – since they can be obtained efficiently and objectively, and appear to deviate from normative values significantly with systemic cortical alterations – could be useful indicators of cerebral cortical health.
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Affiliation(s)
- Zheng Zhang
- Department of Biomedical Engineering, University of North Carolina Chapel Hill, NC, USA
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