Bilateral Representations of Touch in the Primary Somatosensory Cortex
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Assessment of Upper Limb Sensory Deficit in People with Type 2 Diabetes Mellitus – a Descriptive Study
International Journal of Research in Engineering, Science and Management 503 Volume-2, Issue-7, July-2019 www.ijresm.com | ISSN (Online): 2581-5792 Assessment of Upper Limb Sensory Deficit in People with Type 2 Diabetes Mellitus – A Descriptive Study Amrita Ghosh1, Shreejan Regmi2, Trapthi Kamath3 1,3Assistant Professor, Department of Neurology, R. V. College of Physiotherapy, Bangalore, India 2Student, Department of Neurology, R. V. College of Physiotherapy, Bangalore, India Abstract: Background and objective of study: The term diabetes multiple etiology characterized by chronic hyperglycemia with mellitus describes a metabolic disorder of multiple etiology disturbance of carbohydrate, fat and protein metabolism characterized by chronic hyperglycemia with disturbance of resulting from deficit in insulin secretion, insulin action or both carbohydrate, fat and protein metabolism resulting from deficit in [1]. Diabetic patients often develop different chronic insulin secretion, insulin action or both. Neurologic complications occur in diabetes mellitus where small fiber damage affects complications which decrease their quality of life [2]. Diabetes sensation of temperature, light touch, pinprick, and pain. Large mellitus(DM)-related complications include neuropathy, fiber damage diminishes vibratory sensation, position sense, retinopathy, nephropathy, cardiovascular and musculoskeletal muscle strength, sharp-dull discrimination, and two-point disease [3]. discrimination. Numerous prior studies had shown that abnormal Diabetes is one of -
The Roles and Functions of Cutaneous Mechanoreceptors Kenneth O Johnson
455 The roles and functions of cutaneous mechanoreceptors Kenneth O Johnson Combined psychophysical and neurophysiological research has nerve ending that is sensitive to deformation in the resulted in a relatively complete picture of the neural mechanisms nanometer range. The layers function as a series of of tactile perception. The results support the idea that each of the mechanical filters to protect the extremely sensitive recep- four mechanoreceptive afferent systems innervating the hand tor from the very large, low-frequency stresses and strains serves a distinctly different perceptual function, and that tactile of ordinary manual labor. The Ruffini corpuscle, which is perception can be understood as the sum of these functions. located in the connective tissue of the dermis, is a rela- Furthermore, the receptors in each of those systems seem to be tively large spindle shaped structure tied into the local specialized for their assigned perceptual function. collagen matrix. It is, in this way, similar to the Golgi ten- don organ in muscle. Its association with connective tissue Addresses makes it selectively sensitive to skin stretch. Each of these Zanvyl Krieger Mind/Brain Institute, 338 Krieger Hall, receptor types and its role in perception is discussed below. The Johns Hopkins University, 3400 North Charles Street, Baltimore, MD 21218-2689, USA; e-mail: [email protected] During three decades of neurophysiological and combined Current Opinion in Neurobiology 2001, 11:455–461 psychophysical and neurophysiological studies, evidence has accumulated that links each of these afferent types to 0959-4388/01/$ — see front matter © 2001 Elsevier Science Ltd. All rights reserved. a distinctly different perceptual function and, furthermore, that shows that the receptors innervated by these afferents Abbreviations are specialized for their assigned functions. -
Dissociation Between Awareness and Spatial Coding: Evidence from Unilateral Neglect
Dissociation between Awareness and Spatial Coding: Evidence from Unilateral Neglect Barbara Treccani1, Roberto Cubelli1, Roberta Sellaro1, Carlo Umiltà2, and Sergio Della Sala3 Downloaded from http://mitprc.silverchair.com/jocn/article-pdf/24/4/854/1777452/jocn_a_00185.pdf by MIT Libraries user on 17 May 2021 Abstract ■ Prevalent theories about consciousness propose a causal re- dissociate. A patient with left neglect, who was not aware of lation between lack of spatial coding and absence of conscious contralesional stimuli, was able to process their color and po- experience: The failure to code the position of an object is sition. However, in contrast to (ipsilesional) consciously per- assumed to prevent this object from entering consciousness. ceived stimuli, color and position of neglected stimuli were This is consistent with influential theories of unilateral neglect processed separately. We propose that individual object fea- following brain damage, according to which spatial coding of tures, including position, can be processed without attention neglected stimuli is defective, and this would keep their process- and consciousness and that conscious perception of an ob- ing at the nonconscious level. Contrary to this view, we report ject depends on the binding of its features into an integrated evidence showing that spatial coding and consciousness can percept. ■ INTRODUCTION the effects of processing of neglected stimuli on responses Awareness of a stimulus can be defined as the explicit to stimuli presented in the intact hemispace. Properties knowledge of its physical and semantic properties or sim- that can be processed implicitly include color and shape, ply of its existence. This knowledge can be demonstrated identity of alphanumerical symbols, and even the mean- by direct reports of the perception of the stimulus; for ing of words and pictures (Della Sala, van der Meulen, example, by naming it, categorizing it, or just by signaling Bestelmeyer, & Logie, 2010; Làdavas, Paladini, & Cubelli, its presence. -
Spatial Stroop with Directional Cues
Manuscript accepted for publication in “Journal of Clinical and Experimental Neuropsychology” Increased attentional load moves the left to the right Mario Bonato1,2 * and Simone Cutini3,4 1 Department of Experimental Psychology, Ghent University 2 Department of General Psychology, University of Padova 3 Department of Developmental Psychology, University of Padova 4 Center for Cognitive Neurosciences, University of Padova Running head: Load-dependent contralesional mislocalizations * Corresponding author: Dr. Mario Bonato, Department of Experimental Psychology, Ghent University, Henri Dunantlaan 2, B-9000 Ghent, Belgium e-mail: [email protected] Abstract Introduction Unilateral brain damage can heterogeneously alter spatial processing. Very often brain-lesioned patients fail to report (neglect) items appearing within the contralesional space. Much less often patients mislocalize items’ spatial position. We investigated whether a top-down attentional load manipulation (dual-tasking), known to result in contralesional omissions even in apparently unimpaired cases, might also induce spatial mislocalizations. Method Nine right-hemisphere damaged patients performed three computer-based tasks encompassing different levels of attentional load. The side of appearance of visual targets had to be reported either in isolation or while processing additional information (visual or auditory dual-task). Spatial mislocalizations (from the contralesional hemispace towards the ipsilesional -unaffected- one) were then contrasted with omissions both within and across tasks, at individual as well as at group level. Results The representation of ipsilesional targets was accurate and not affected by dual-tasking requirements. Contralesional targets were instead often omitted and, under dual-task conditions, also mislocalized by four patients. Three cases reported a significant number of left targets as appearing on the right (alloesthesia). -
Tactile Receptors Underneath Skin (Superficial) Pressure Sensation : Deformation of Deep Tissue Vibration Sensation: Rapidly Repetitive Sensory Signals
Somatic Sensations Col. Asst.Prof. Dangjai Souvannakitti MD. PhD. Department of Physiology Phramongkutklao College of Medicine 1 Objective : Be able to… Describe classification of somatic of sensation Pathways of each somatic sensation Describe two point discrimination threshold Describe vibration pathway Describe itching/tickling pathway Describe position senses Describe Temperature (cold/warmth) sensation Describe cortical representation and plasticity 2 Outline Somatic sensation classification Pathways of somatic sensation : Free (or naked or bare) nerve endings/Merkel disk receptors/Meissner’s corpuscles/Ruffini endings/Pacinian corpuscles/Hair end-organ (or hair follicle)/Field receptor Receptive field and Two point discrimination Vibration Itching/tickling Position senses Temperature 3 Cortical representation and plasticity Somatic Sensations Classified by receptor location : – Exteroceptive sensation (Cutaneous sense) : from skin – Deep sensation : from deep tissues fasciae, muscles, bones (deep pressure, pain, vibration) – Proprioceptive sensation from physical state of body posture – *Visceral sensation from internal organs * Some text may not include in somatic sensation 4 Classified by stimulus energy: – Mechanoreceptive somatic senses • Tactile sense: touch, pressure, vibration, tickle senses • Position sense – Thermoreceptive senses – warmth & cold – Pain senses – chemical releasing from tissues damage 5 Classified by neurological classification – Epicritic sensation • Fine aspects of touch – encapsulated -
Abadie's Sign Abadie's Sign Is the Absence Or Diminution of Pain Sensation When Exerting Deep Pressure on the Achilles Tendo
A.qxd 9/29/05 04:02 PM Page 1 A Abadie’s Sign Abadie’s sign is the absence or diminution of pain sensation when exerting deep pressure on the Achilles tendon by squeezing. This is a frequent finding in the tabes dorsalis variant of neurosyphilis (i.e., with dorsal column disease). Cross References Argyll Robertson pupil Abdominal Paradox - see PARADOXICAL BREATHING Abdominal Reflexes Both superficial and deep abdominal reflexes are described, of which the superficial (cutaneous) reflexes are the more commonly tested in clinical practice. A wooden stick or pin is used to scratch the abdomi- nal wall, from the flank to the midline, parallel to the line of the der- matomal strips, in upper (supraumbilical), middle (umbilical), and lower (infraumbilical) areas. The maneuver is best performed at the end of expiration when the abdominal muscles are relaxed, since the reflexes may be lost with muscle tensing; to avoid this, patients should lie supine with their arms by their sides. Superficial abdominal reflexes are lost in a number of circum- stances: normal old age obesity after abdominal surgery after multiple pregnancies in acute abdominal disorders (Rosenbach’s sign). However, absence of all superficial abdominal reflexes may be of localizing value for corticospinal pathway damage (upper motor neu- rone lesions) above T6. Lesions at or below T10 lead to selective loss of the lower reflexes with the upper and middle reflexes intact, in which case Beevor’s sign may also be present. All abdominal reflexes are preserved with lesions below T12. Abdominal reflexes are said to be lost early in multiple sclerosis, but late in motor neurone disease, an observation of possible clinical use, particularly when differentiating the primary lateral sclerosis vari- ant of motor neurone disease from multiple sclerosis. -
Deficits in Response Space Following Unilateral Striatal Dopamine Depletion in the Rat
The Journal of Neuroscience, March 1989, g(3): 983-989 Deficits in Response Space Following Unilateral Striatal Dopamine Depletion in the Rat Verity J. Brown and Trevor W. Robbins Department of Experimental Psychology, University of Cambridge, Cambridge CB2 3EB, United Kingdom Hungry rats were trained to report the occurrence and lo- location of stimuli on one side of spaceonly, before depleting cation of brief, unpredictable visual stimuli presented to the DA in the striatum contralateral to that side. In another group left of their heads in 1 of 2 response locations. After training, of rats, DA was depleted from the striatum on the sameside as they received unilateral infusions of 6-hydroxydopamine, de- the discrimination, as a control procedure for nonspecific post- pleting dopamine throughout the head of the caudate pu- operative effects. tamen, either on the left or the right side, that is, either A secondquestion of importance concerning striatal neglect ipsilateral or contralateral to the side on which they were is whether a possible hemispatial deficit induced by unilateral required to respond. striatal lesionsis restricted to one side of the body or, altema- Following an ipsilateral lesion there were no impairments tively, is relative, or allocentric, in nature. Kinsboume and War- in localization of the visual discriminanda and there was no rington (1962) and Bisiach and Luzzatti (1978) found parietal lengthening of reaction time. The contralaterally lesioned neglect not only for left retinotopic, but also for left conceptual rats, however, showed considerably lengthened reaction space.In a human reaction time task, Ladavas (1987) described times to both stimuli and a profound bias to the nearer of 2 components of the neglect; there was not only an overall the 2 response locations. -
Reference of Sensation at the Spinal Level by P
J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.19.2.88 on 1 May 1956. Downloaded from J. Neurol. Neurosurg. Psychiat., 1956, 19, 88. REFERENCE OF SENSATION AT THE SPINAL LEVEL BY P. W. NATHAN From the Neurological Research Unit of the Medical Research Council, National Hospital, Queen Square, London After the spino-thalamic tract has been cut in The purpose of this paper is to describe the man, loss of sensation of pain and temperature features of such reference of sensation and to record caudal to the lesion is to be expected. In a small it in conditions other than in those previously proportion of patients, although analgesia-in the reported. Certain related phenomena will also be usual sense of the term-is present, painful or described. An investigation of the various forms thermal stimuli applied to parts of the body caudal of the reference of sensation will be reported; and to the lesion arouse a sensation, which is felt, not the possible underlying mechanism and the ana- at the place actually stimulated, but in a normally tomical implications will be considered. innervated part of the body. Thus, a pin applied to the analgesic left leg, for instance, may cause a Observations sensation referred to the normally innervated right has been observed in This reference of sensation Protected by copyright. leg. one patient having an amputation of an upper This form of reference of sensation following the limb, in one patient with a thrombosis of the cutting of the spino-thalamic tract on one side of anterior spinal artery, and in 13 patients following the cord was described by Ray and Wolff in 1945. -
Body Awareness Disorders: Dissociations Between Body-Related Visual and Somatosensory Information Laure Pisella, Laurence Havé, Yves Rossetti
Body awareness disorders: dissociations between body-related visual and somatosensory information Laure Pisella, Laurence Havé, Yves Rossetti To cite this version: Laure Pisella, Laurence Havé, Yves Rossetti. Body awareness disorders: dissociations between body- related visual and somatosensory information. Brain - A Journal of Neurology , Oxford University Press (OUP), 2019, 142 (8), pp.2170-2173. 10.1093/brain/awz187. hal-02346581 HAL Id: hal-02346581 https://hal.archives-ouvertes.fr/hal-02346581 Submitted on 7 Nov 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. BADs: dissociations between body-related visual and somatosensory information L. Pisella1, L. Havé1,3 & Y. Rossetti1,2 1 ImpAct Team, Lyon Neuroscience Research Center CRNL, INSERM U1028, CNRS UMR5292 and University Claude Bernard Lyon I, Villeurbanne, France 2 Plate-forme Mouvement et Handicap, Hospices Civils de Lyon, Centre de Recherche en Neurosciences de Lyon, 69500 Bron, France 3 Hôpital d'instruction des armées Desgenettes, 69275 Lyon, France Glossary : Precuneus: medial part of the posterior parietal cortex, between the occipital (cuneus) and the anterior parietal (paracentral lobule) cortices, well located for visual- somatosensory integration. Body image typically depicts mental representation of one’s own body, arising from all sources of sensory and cognitive information, whereas body schema is used to depict the unconscious use of sensory information required by our motor system to maintain body posture and produce accurate movements. -
Somatosensory Integration and Masking of Complex Tactile Information: Peripheral and Cortical Contributions
brain sciences Article Somatosensory Integration and Masking of Complex Tactile Information: Peripheral and Cortical Contributions Steven R. Passmore 1,2,3,*, Niyousha Mortaza 3 , Cheryl M. Glazebrook 3, Bernadette Murphy 4 and Timothy D. Lee 1 1 Department of Kinesiology, McMaster University, Hamilton, ON L8S 4K1, Canada; [email protected] 2 Research Department, New York Chiropractic College, Seneca Falls, NY 13148, USA 3 Faculty of Kinesiology and Recreation Management, University of Manitoba, Winnipeg, MB R3T 2N2, Canada; [email protected] (N.M.); [email protected] (C.M.G.) 4 Faculty of Health Sciences, Ontario Tech University, Oshawa, ON L1G 0C5, Canada; [email protected] * Correspondence: [email protected]; Tel.: +1-204-474-6552 Received: 29 October 2020; Accepted: 4 December 2020; Published: 9 December 2020 Abstract: Nerve paresthesia is a sensory impairment experienced in clinical conditions such as diabetes. Paresthesia may “mask” or “compete” with meaningful tactile information in the patient’s sensory environment. The two objectives of the present study were: (1) to determine if radiating paresthesia produces a peripheral mask, a central mask, or a combination; (2) to determine if a response competition experimental design reveals changes in somatosensory integration similar to a masking design. Experiment 1 assessed the degree of masking caused by induced radiating ulnar nerve paresthesia (a concurrent non-target stimulus) on a vibrotactile Morse code letter acquisition task using both behavioral and neurophysiological measures. Experiment 2 used a response competition design by moving the radiating paresthesia to the median nerve. This move shifted the concurrent non-target stimulus to a location spatially removed from the target stimuli. -
Functional Sensory Symptoms
Handbook of Clinical Neurology, Vol. 139 (3rd series) Functional Neurologic Disorders M. Hallett, J. Stone, and A. Carson, Editors http://dx.doi.org/10.1016/B978-0-12-801772-2.00024-2 © 2016 Elsevier B.V. All rights reserved Chapter 24 Functional sensory symptoms J. STONE1* AND M. VERMEULEN2 1Department of Clinical Neurosciences, Centre for Clinical Brain Sciences, University of Edinburgh, Edinburgh, UK 2Department of Neurology, Academic Medical Center, Amsterdam, The Netherlands Abstract Functional (psychogenic) sensory symptoms are those in which the patient genuinely experiences alter- ation or absence of normal sensation in the absence of neurologic disease. The hallmark of functional sen- sory symptoms is the presence of internal inconsistency revealing a pattern of symptoms governed by abnormally focused attention. In this chapter we review the history of this area, different clinical presentations, diagnosis (including sensitivity of diagnostic tests), treatment, experimental studies, and prognosis. Altered sensation has been a feature of “hysteria” since descriptions of witchcraft in the middle ages. In the 19th century hysteric sensory stigmata were considered a hallmark of the condition. Despite this long history, relatively little attention has been paid to the topic of functional sensory disturbance, compared to functional limb weakness or functional movement disorders, with which it commonly coexists. There are recognizable clinical patterns, such as hemisensory disturbance and sensory disturbance fin- ishing at the groin or shoulder, but in keeping with the literature on reliability of sensory signs in neurology in general, the evidence suggests that physical signs designed to make a positive diagnosis of functional sensory disorder may not be that reliable. -
Coding of Spatial Lnformation in the with Neglect Following Parietal Lobe
Coding of Spatial Lnformation in the Somatosensory System: Evidence Erom Patients with Neglect following Parietal Lobe Damage Morris Moscovitch and Marlene Behrmann University of Toronto and Rotnian Research Institute of Baycrest Centre, Toronto Downloaded from http://mitprc.silverchair.com/jocn/article-pdf/6/2/151/1755120/jocn.1994.6.2.151.pdf by guest on 18 May 2021 Abstract Unilateral parietal lobe darnage, particularly in the right both the palm up and the palm down position. Patients ne- cerehral hemisphere, leads to neglect of stimuli on the contra- glected the stimuli on the side of space contralateral to the 1ater;rl side. To determine the reference frame within which lesion regardless of hand position. These results indicate that neglect operates in the somatosensory system, 11 patients with point-localization in the somatosensory system is accomplished unilateral neglect were touched simultaneously on the left and with respect to a spatially defined frame-of-referenceand not right side of the wrist of one hand. The hand was tested in strictly with respect to somatotopically defined coordinates. INTRODUCTION stimulation of the sensory surface projecting to the le- sioned hemisphere. Recent work in vision has refuted Individuals with damage to the right parietal lobes often the notion that this view can account for all aspects of suffer from hemineglect, a dramatic attentional disorder neglect. A number of investigators have shown that what in which information on the left side is ignored (Bisiach is neglected is not necessarily the stimulus in the left & Vattar, 1988; Critchley, 1953; Heilman, Watson, & Val- visual field, but rather the left-most item of a set of enstcin, 1985; Mesulam, 1981).