Volume 8, Issue 6, November 2020, Page: 267-273
Postural Instability in a Young Dyslexic Adult Improved by Hebbian Pulse-width Modulated Lighting
Albert Le Floch, Laser Physics Laboratory, University of Rennes 1, Rennes, France; Quantum Electronics and Chiralities Laboratory, Rennes, France
Samuel Henriat, Clinic of Podiatry, Pontivy, France
Rosane Fourage, Institute of Training in Podology, Ergotherapy and Kinesitherapy, Rennes, France
Guy Ropars, Laser Physics Laboratory, University of Rennes 1, Rennes, France
Received: Oct. 14, 2020;       Accepted: Oct. 23, 2020;       Published: Nov. 4, 2020
DOI: 10.11648/j.ajim.20200806.15      View  58      Downloads  52
Background: Postural stability is linked to vision in everyone, since when the eyes are closed stability decreases by a factor of 2 or more. However, in persons with dyslexia postural stability is often deficient even when the eyes are open, since they show deficits in motor as well as specific cognitive functions. In dyslexics we have shown that abnormal symmetry between retinal Maxwell’s centroid outlines occurs, perturbing the interhemispheric connections. We have also shown that pulse-width modulated lighting can compensate for this lack of asymmetry, improving the reading skills. Objective: As the postural stability and the vision are correlated, one may wonder if the excess of the postural instability recorded in a young adult with dyslexia can also be reduced by a pulse-width modulated light controlling the Hebbian synaptic plasticity. Method: Using a force platform we compared the postural responses of an observer without dyslexia with the responses of a subject with dyslexia, by measuring their respective standing postures with eyes open looking at a target in a room with either continuous or pulse lighting. Results: There was no effect of changing the lighting conditions on the postural control of the subject without dyslexia. However, we found that the postural stability of the subject with dyslexia which was actually impaired during continuous light, but was greatly improved when a 80 Hz pulsed light frequency was used. Importantly, the excursions of the surface area of the center of pressure on the force platform were reduced by a factor of 2.3. Conclusion: The postural instability in a dyslexic person can be improved by pulse-width modulated lighting.
Neural Connectivity, Postural Control, Visual Interactions, Synaptic Plasticity, Dyslexia, Pulse Light Effect
To cite this article
Albert Le Floch, Samuel Henriat, Rosane Fourage, Guy Ropars, Postural Instability in a Young Dyslexic Adult Improved by Hebbian Pulse-width Modulated Lighting, American Journal of Internal Medicine. Vol. 8, No. 6, 2020, pp. 267-273. doi: 10.11648/j.ajim.20200806.15
Copyright © 2020 Authors retain the copyright of this article.
This article is an open access article distributed under the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/) which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
W. M. Paulus, A. Straube, T. Brandt, Visual stabilization of posture, Physiological stimulus characteristics and clinical aspects, Brain 107 (1984) 1143-1163.
T. T. Lê, Z. Kapoula, Role of ocular convergence in the Romberg quotient, Gait Posture 27 (2008) 493-500.
D. N. Lee, The optic flow field: the foundation of vision, Philos Trans R Soc Lond B Biol Sci. 290 (1980) 169-179.
E. E. Hansson, A. Beckman, A. Håkansson, Effect of vision, proprioception, and the position of the vestibular organ on postural sway, Acta Otolaryngol. 130 (2010) 1358-1363. DOI: 10.3109/00016489.2010.498024.
M. Piirtola, P. Era, Force platform measurements as predictors of falls among older people - a review, Gerontology 52 (2006) 1-16.
M. Wade, G. Jones, The Role of Vision and Spatial Orientation in the Maintenance of Posture, Physical therapy 77 (1997) 619-628.
T. Vidyasagar, Neural underpinnings of dyslexia as a disorder of visuo-spatial attention, Clinical & experimental optometry 87 (2004) 4-10. https://doi.org/10.1111/j.14440938.2004.tb03138.x.
J. Stein, The magnocellular theory of developmental dyslexia, Dyslexia 7 (2001) 12-36.
M. Habib, The neurological basis of developmental dyslexia: An overview and working hypothesis, Brain 123 (2001) 2373-2399. DOI: 10.1093/brain/123.12.2373.
R. I. Nicolson, A. Fawcett, P. Dean, Developmental dyslexia: The cerebellar deficit hypothesis, Trends in Neurosciences 24 (2001) 508-511. DOI: 10.1016/S0166-2236(00)01896-8.
H. Martins Da Cunha, Syndrome de déficience posturale, Actualité en rééducation fonctionnelle et en réadaptation. 4e série. Paris: Masson (1979) 27-31.
J. Barela, P. de Freitas, A. Viana, M. Razuk, Dyslexia and the Integration of Sensory Cues into Motor Action, Psychology 5 (2014) 51107. DOI: 10.4236/psych.2014.516192.
C. Stoodley, A. Fawcett, R. Nicolson, J. Stein, Impaired balancing ability in dyslexic children, Experimental brain research 167 (2005) 370-380. DOI: 10.1007/s00221-005-0042-x.
T. Pozzo, P. Vernet, C. Creuzot-Garcher, F. Robichon, A. Bron, P. Quercia, Static postural control in children with developmental dyslexia, Neuroscience letters 403 (2006) 211-215. DOI: 10.1016/j.neulet.2006.03.049.
Z. Kapoula, M. Pia Bucci, Postural control in dyslexic and non-dyslexic children, Journal of neurology 254 (2007) 1174-1183. DOI: 10.1007/s00415-006-0460-0.
S. Vieira, P. Quercia, C. Michel, T. Pozzo, F. Bonnetblanc, Cognitive demands impair postural control in developmental dyslexia: A negative effect that can be compensated, Neuroscience letters 462 (2009) 125-129. DOI: 10.1016/j.neulet.2009.06.093.
M. Pia Bucci, E. Bui, C.-L. Gerard, The Effect of a Stroop-like Task on Postural Control in Dyslexic Children, PloS one. 8. (2013) e77920. DOI: 10.1371/journal.pone.0077920.
F. Ramus, E. Pidgeon, U. Frith, The Relationship Between Motor Control and Phonology in Dyslexic Children, Journal of child psychology and psychiatry, and allied disciplines 44 (2003) 712-722. DOI: 10.1111/1469-7610.00157.
A. Kirby, D. A. Sugden, Children with developmental coordination disorders, J R Soc Med. 100 (2007) 182–186. DOI: 10.1258/jrsm.100.4.182.
A. Gaddis, K. S. Rosch, B. Dirlikov, D. Crocetti, L. MacNeil, A. D. Barber et al., Motor overflow in children with attention-deficit/hyperactivity disorder is associated with decreased extent of neural activation in the motor cortex, Psychiatry Res. 30 (2015) 488-495. DOI: 10.1016/j.pscychresns.2015.08.001.
E. Finn, X. Shen, J. Holahan, D. Scheinost, C. Lacadie, X. Papademetris, et al., Disruption of Functional Networks in Dyslexia: A Whole-Brain, Data-Driven Analysis of Connectivity, Biological psychiatry 76 (2013) 397-404. DOI: 10.1016/j.biopsych.2013.08.031.
S. Dehaene, L. Cohen, The unique role of the visual word form area in reading, Trends in cognitive sciences 15 (2011) 254-262. DOI: 10.1016/j.tics.2011.04.003.
D. Bishop, Cerebral Asymmetry and Language Development: Cause, Correlate, or Consequence?, Science 340 (2013) 1230531. DOI: 10.1126/science.1230531.
N. Tzourio-Mazoyer, Intra- and Inter-hemispheric Connectivity Supporting Hemispheric Specialization, In: H. Kennedy, D. C. Van Essen, Y. Christen, editors. Micro-, Meso- and Macro-Connectomics of the Brain [Internet]. Cham (CH): Springer; 2016. Available from: https://www.ncbi.nlm.nih.gov/books/NBK435764/doi: 10.1007/978-3-319-27777-6_9.
P. K. Mutha, K. Y. Haaland, R. L. Sainburg, The effects of brain lateralization on motor control and adaptation, J Mot Behav. 44 (2012) 455-469. DOI: 10.1080/00222895.2012.747482.
S. E. Parlow A Closer Look at Motor Overflow in Dyslexic Children. [Washington, D. C.], (1991). Distributed by ERIC Clearinghouse, https://eric.ed.gov/?id=ED333673.
K. Hoy, P. Fitzgerald, J. L. Bradshaw, C. Armatas, N. Georgiou-Karistianis, Investigating the cortical origins of motor overflow, Brain Res. Brain Res. Rev. 46 (2004) 315-327. DOI: 10.1016/j.brainresrev.2004.07.013.
E. D'Agati, L. Casarelli, M. Bernarda, A. Pasini, Overflow movements and white matter abnormalities in ADHD, ProgNeuropsychopharmacol Biol Psychiatry 34 (2010) 441-445. DOI: 10.1016/j.pnpbp.2010.01.013.
P. Addamo, M. Farrow, K. Hoy, J. L Bradshaw, N. Georgiou-Karistianis, The effects of age and attention on motor overflow production—A review, Brain Res Rev 54 (2007) 189-204. DOI: 10.1016/j.brainresrev.2007.01.004.
A. Fawcett, R. I. Nicolson, Dyslexia: The Role of the Cerebellum, in book: Dyslexia in Context: Research, Policy and Practice, (2008). 13-22. DOI: 10.1002/9780470777916.ch2.
J. L. Needle, A. J. Fawcett, R. I. Nicholson, Balance and dyslexia: An investigation of adults’ abilities, European Journal of Cognitive Psychology 18 (2006) 909-936. https://doi.org/10.1080/09541440500412304.
R. L. Brookes, S. Tinkler, R. I. Nicholson, A. J. Fawcett, Striking the right balance: Motor difficulties in children and adults with dyslexia, Dyslexia 16 (2010) 358-373. http://dx.doi.org/10.1002/dys.420.
M. Patel, M. Magnusson, D. Lush, S. Gomez, P. A. Fransson, Effects of dyslexia on postural control in adults, Dyslexia 16 (2010) 162-174.
Y. Ouchi, H. Okada, E. Yoshikawa, S. Nobezawa, M. Futatsubashi, Brain activation during maintenance of standing postures in humans, Brain 122 (1999) 329-338.
F. Horak, Postural orientation and equilibrium: What do we need to know about neural control of balance to prevent falls? Age and ageing 35 (2006) ii7–ii11. DOI: 10.1093/ageing/afl077.
R. L. Buckner, The cerebellum and cognitive function: 25 years of insight from anatomy and neuroimaging, Neuron. 80 (2013) 807-815. DOI: 10.1016/j.neuron.2013.10.044.
R. Chiba, K. Takakusaki, J. Ota, A. Yozu, N. Haga, Human upright posture control models based on multisensory inputs; in fast and slow dynamics, Neuroscience research. 104 (2016) 96-104. DOI: 10.1016/j.neures.2015.12.002.
J. D. Schmahmann. The cerebellum and cognition, Neuroscience Letters 688 (2019) 62-75. https://doi.org/10.1016/j.neulet.2018.07.005.
M. McPhillips, P. G. Hepper, G. Mulhern, Effects of replicating primary-reflex movements on specific reading difficulties in children: A randomised, double-blind, controlled trial, Lancet. 355 (2000) 537-41. DOI: 10.1016/S0140-6736(99)02179-0.
A. Le Floch, G. Ropars, Left – Right asymmetry of the Maxwell spot centroids in adults without and with dyslexia, Proceedings of the Royal Society B: Biological Sciences 284 (2017) 20171380. DOI: 10.1098/rspb.2017.1380.
D. H. Hubel, Eye, brain, and vision. New York, NY: Scientific American Library (1988).
D. H. Hubel, T. N. Wiesel, Brain and visual perception. New York, Oxford University Press, Inc (2005).
T. S. Kapteyn, W. Bles, C. Njiokiktjien, L. Kodde, C. Massen, & J. M. F. Mol, Standardisation in platform stabilometry being part of posturography, Agressologie 24 (1983) 321-326.
F. Scoppa, R. Capra, M. Gallamini, R. Shiffer, Clinical stabilometry standardization Basic definitions - Acquisition interval - Sampling frequency, Gait & posture 37 (2012) 290-292. DOI: 10.1016/j.gaitpost.2012.07.009.
M. Yamamoto, K. Ishikawa, M. Aoki, K. Mizuta, Y. Ito, M. Asai et al., Japanese standard for clinical stabilometry assessment: Current status and future directions, Auris Nasus Larynx 45 (2018) 201-206. DOI: 10.1016/j.anl.2017.06.006.
N. Pinsault, N. Vuillerme, Test-retest reliability of centre of foot pressure measures to assess postural control during unperturbed stance, Medical engineering & physics 31 (2008) 276-286. DOI: 10.1016/j.medengphy.2008.08.003.
P. M. Gaget, G. Biggo, La mesure en Posturologie, Institut de Posturologie (http://ada-posturologie.fr/MesureEnPosturologie.htm), Paris.
D. O. Hebb, The organization of behavior: neuropsychological theory. New York: Wiley (1949).
M. Glickstein, How are visual areas of the brain connected to motor areas for the sensory guidance of movement? Trends Neurosci. 23 (2000) 613-617.
Y. Han, J. M. Kebschull, R. Campbell, D. Cowan, F. Imhof, A. M. Zador, et al. The logic of single-cell projections from visual cortex, Nature 556 (2018) 51-56. DOI: 10.1038/nature26159.
P. Brotchie, R. A. Andersen, L. Snyder, S. J. Goodman, Head position signals used by parietal neurons to encode locations of visual stimuli, Nature 375 (1995) 232-235. DOI: 10.1038/375232a0.
B. Mimica et al., Efficient cortical coding of 3D posture in freely behaving rats, Science 362 (2018) 584-598. DOI: https://doi.org/10.1101/307785.
Browse journals by subject