Clinical trial NCT05972200: V5/MT Stimulation on Reading and Reading-related Measures in Developmental Dyslexia
Official title: Probing the Efficacy of V5/MT Stimulation on Reading and Reading-related Measures in Children and Adolescents With Developmental Dyslexia
Study type: INTERVENTIONAL
Overall status: RECRUITING
Phase: NA
Conditions: Developmental Dyslexia
Keywords: Children
Adolescents
tDCS
transcranial direct current stimulation
neurodevelopmental disorders
non-invasive brain stimulation
transcranial electrical stimulation
EEG
reading abilities
Lead sponsor: Bambino Gesù Hospital and Research Institute
Sponsor class: OTHER
First posted: 2023-08-02
Enrollment: 36
Sex: ALL
Minimum age (years): 8
Maximum age (years): 13
Standard ages: CHILD
Accepts healthy volunteers: yes
Allocation: RANDOMIZED
Intervention model: CROSSOVER
Primary purpose: TREATMENT

Brief summary: The present study grounds on the absence of evidence-based treatment in individuals with developmental dyslexia (DD). At this topic, the present study will explore the potential effect of transcranial direct current stimulation (tDCS) over left hemispheric direct Lateral Geniculate Nucleus (LGN)-V5/MT pathway, cerebral areas usually disrupted in individuals with DD.

The investigators hypothesized that active tDCS over V5/MT will boost reading skills in children and adolescents with DD. On the contrary, sham (placebo condition) tDCS over V5/MT or active (control condition) tDCS over V1 will not have significant effect in improving reading skills. Further, both active and sham tDCS will be safe and well tolerated.

Detailed description: Over the last few decades, a huge number of studies has revealed that Developmental Dyslexia (DD), a brain-based neurodevelopmental disorder characterized by a severe and persistent impairment in the acquisition of reading skills may depend on multiple neurocognitive impairments, ranging from language-specific to cognitive-general deficits. Besides the most influential hypothesis of a phonological core deficit, there is also evidence for difficulties in low-level visual-temporal information processing, as the magnocellular deficit theory supports, as well as for visual-spatial attentional deficits, visual-perceptual impairments, and rapid automatized naming (RAN)-speed deficits.

Replicated structural/functional neuroimaging studies have demonstrated a DD hypoactivation relative to typical readers in the left temporo-occipital regions-critical for the automatic visual processing of word strings or print-and in the left temporo-parietal regions-important for grapheme-to-phoneme mapping.

Moreover, findings from animal models and post mortem studies in humans suggest that DD might also be associated with structural alterations in subcortical sensory pathways, particularly in visual and auditory thalamic nuclei and in their connections with high-order sensory cortices (i.e., the left hemispheric direct Lateral Geniculate Nucleus (LGN)-V5/MT pathway and the left hemispheric direct Medial Geniculate Body (MGB)-mPT pathway). In addition, in adults with DD, left V5/MT-LGN connectivity strength correlated with RAN abilities - a key deficit in DD.

A number of studies have demonstrated the positive effect of transcranial direct current stimulation (tDCS), a non-invasive brain stimulation used for transiently modifying neural activity of target areas, on reading and, particularly, in DD.

However, the few non-invasive brain stimulation studies on improving reading in DD yielded heterogeneous results and this variability might be partly due to the lack of neurobiological understanding of the underlying DD mechanism or to the use of traditional tDCS rather than a more focal technique such as the high-definition tDCS (HD-tDCS).

Starting from this, the aim of the current study is testing the effectiveness of a cutting-edge stimulation technique (i.e., HD-tDCS) in a within-subject experiment involving children and adolescents with DD. Especially, we will work to test i) the specific effect of HD-tDCS over high-order sensory cortices (i.e., V5/MT vs V1) on reading in children with DD; ii) the preconditions and neurobiological mechanisms that lead to high treatment outcomes.

If the stimulation over V5/MT is effective and specifically related to reading improvement, our results could help to i) understand the contribution and neurobiological mechanism of V5/MT in reading of children and adolescents with DD; ii) select criteria for potential responders to non-invasive brain stimulation; iii) develop evidence-based interventions in DD.

Eligibility criteria: Inclusion Criteria:

* Italian speakers right-handed children and adolescents with dyslexia (DSM-5, APA 2013);
* Word/nonword/text reading accuracy and/or speed at least 2 Standard Deviations below the mean for school-age;
* nv IQ ≥ 85;
* normal hearing and normal or corrected-to-normal vision.

Exclusion Criteria:

* Having a comorbidity with other primary psychiatric/neurological diagnosis (e.g., depression, anxiety, autism, ADHD);
* Having a personal history of neurological/medical/genetic diseases;
* Having ongoing drug treatment influencing brain function;
* Having epilepsy o family history of epilepsy.

Primary outcomes:
measure: Text reading accuracy (Experimental reading task)
timeFrame: during procedure
measure: Text reading speed (Experimental reading task)
timeFrame: during procedure
Secondary outcomes:
measure: Word reading accuracy (Experimental reading task)
timeFrame: during procedure
measure: Word reading speed (Experimental reading task)
timeFrame: during procedure
measure: Non-word reading accuracy (Experimental reading task)
timeFrame: during procedure
measure: Non-word reading speed (Experimental reading task)
timeFrame: during procedure
measure: Right visual hemisphere-motion perception (Experimental reading task)
timeFrame: during procedure
measure: Rapid automatized naming letter and number (Experimental reading task)
timeFrame: during procedure
measure: Phoneme blending (Experimental reading task)
timeFrame: during procedure
measure: Eye-movements during reading (Experimental reading task)
timeFrame: during procedure
measure: Spontaneous EEG (Experimental reading task)
timeFrame: during procedure
Other outcomes:
Locations:
city: Roma
country: Italy
facility: Bambino Gesù Hospital and Research Institute
Study officials:
References:
citation: American Psychiatric Association. Diagnostic and statistical manual of mental disorders (5th ed.): DSM 5. Washington, DC: American Psychiatric Association. 2013.
citation: Snowling, M. Dyslexia, 2nd ed.; Blackwell Publishing: Oxford, UK. 2000.
citation: Wolf M, Bowers PG. The double-deficit hypothesis for the developmental dyslexias. Journal of Educational Psychology. 1999; 91(3): 415-438.
citation: Menghini D, Finzi A, Benassi M, Bolzani R, Facoetti A, Giovagnoli S, Ruffino M, Vicari S. Different underlying neurocognitive deficits in developmental dyslexia: a comparative study. Neuropsychologia. 2010 Mar;48(4):863-72. doi: 10.1016/j.neuropsychologia.2009.11.003. Epub 2009 Nov 10.
citation: Vellutino FR, Fletcher JM, Snowling MJ, Scanlon DM. Specific reading disability (dyslexia): what have we learned in the past four decades? J Child Psychol Psychiatry. 2004 Jan;45(1):2-40. doi: 10.1046/j.0021-9630.2003.00305.x.
citation: Melby-Lervag M, Lyster SA, Hulme C. Phonological skills and their role in learning to read: a meta-analytic review. Psychol Bull. 2012 Mar;138(2):322-52. doi: 10.1037/a0026744. Epub 2012 Jan 16.
citation: Schulte-Korne G, Bruder J. Clinical neurophysiology of visual and auditory processing in dyslexia: a review. Clin Neurophysiol. 2010 Nov;121(11):1794-809. doi: 10.1016/j.clinph.2010.04.028. Epub 2010 May 31.
citation: Vidyasagar TR, Pammer K. Dyslexia: a deficit in visuo-spatial attention, not in phonological processing. Trends Cogn Sci. 2010 Feb;14(2):57-63. doi: 10.1016/j.tics.2009.12.003. Epub 2010 Jan 14.
citation: Franceschini S, Gori S, Ruffino M, Pedrolli K, Facoetti A. A causal link between visual spatial attention and reading acquisition. Curr Biol. 2012 May 8;22(9):814-9. doi: 10.1016/j.cub.2012.03.013. Epub 2012 Apr 5.
citation: Bosse ML, Tainturier MJ, Valdois S. Developmental dyslexia: the visual attention span deficit hypothesis. Cognition. 2007 Aug;104(2):198-230. doi: 10.1016/j.cognition.2006.05.009. Epub 2006 Jul 21.
citation: Stenneken P, Egetemeir J, Schulte-Korne G, Muller HJ, Schneider WX, Finke K. Slow perceptual processing at the core of developmental dyslexia: a parameter-based assessment of visual attention. Neuropsychologia. 2011 Oct;49(12):3454-65. doi: 10.1016/j.neuropsychologia.2011.08.021. Epub 2011 Aug 31.
citation: Giovagnoli G, Vicari S, Tomassetti S, Menghini D. The Role of Visual-Spatial Abilities in Dyslexia: Age Differences in Children's Reading? Front Psychol. 2016 Dec 21;7:1997. doi: 10.3389/fpsyg.2016.01997. eCollection 2016.
citation: Wang Z, Cheng-Lai A, Song Y, Cutting L, Jiang Y, Lin O, Meng X, Zhou X. A perceptual learning deficit in Chinese developmental dyslexia as revealed by visual texture discrimination training. Dyslexia. 2014 Aug;20(3):280-96. doi: 10.1002/dys.1475. Epub 2014 Mar 18.
citation: Bowers PG, Wolf, M. Theoretical links among naming speed, precise timing mechanisms and orthographic skill in dyslexia. Reading and Writing.1993; 51: 69-85.
citation: Richlan F, Kronbichler M, Wimmer H. Meta-analyzing brain dysfunctions in dyslexic children and adults. Neuroimage. 2011 Jun 1;56(3):1735-42. doi: 10.1016/j.neuroimage.2011.02.040. Epub 2011 Feb 19.
citation: Richlan F. Developmental dyslexia: dysfunction of a left hemisphere reading network. Front Hum Neurosci. 2012 May 1;6:120. doi: 10.3389/fnhum.2012.00120. eCollection 2012.
citation: Livingstone MS, Rosen GD, Drislane FW, Galaburda AM. Physiological and anatomical evidence for a magnocellular defect in developmental dyslexia. Proc Natl Acad Sci U S A. 1991 Sep 15;88(18):7943-7. doi: 10.1073/pnas.88.18.7943.
citation: Galaburda AM, Menard MT, Rosen GD. Evidence for aberrant auditory anatomy in developmental dyslexia. Proc Natl Acad Sci U S A. 1994 Aug 16;91(17):8010-3. doi: 10.1073/pnas.91.17.8010.
citation: Giraldo-Chica M, Hegarty JP 2nd, Schneider KA. Morphological differences in the lateral geniculate nucleus associated with dyslexia. Neuroimage Clin. 2015 Mar 20;7:830-6. doi: 10.1016/j.nicl.2015.03.011. eCollection 2015.
citation: Muller-Axt C, Anwander A, von Kriegstein K. Altered Structural Connectivity of the Left Visual Thalamus in Developmental Dyslexia. Curr Biol. 2017 Dec 4;27(23):3692-3698.e4. doi: 10.1016/j.cub.2017.10.034. Epub 2017 Nov 16.
citation: Tschentscher N, Ruisinger A, Blank H, Diaz B, von Kriegstein K. Reduced Structural Connectivity Between Left Auditory Thalamus and the Motion-Sensitive Planum Temporale in Developmental Dyslexia. J Neurosci. 2019 Feb 27;39(9):1720-1732. doi: 10.1523/JNEUROSCI.1435-18.2018. Epub 2019 Jan 14.
citation: Kirimoto H, Ogata K, Onishi H, Oyama M, Goto Y, Tobimatsu S. Transcranial direct current stimulation over the motor association cortex induces plastic changes in ipsilateral primary motor and somatosensory cortices. Clin Neurophysiol. 2011 Apr;122(4):777-83. doi: 10.1016/j.clinph.2010.09.025. Epub 2010 Nov 11.
citation: Turkeltaub PE, Benson J, Hamilton RH, Datta A, Bikson M, Coslett HB. Left lateralizing transcranial direct current stimulation improves reading efficiency. Brain Stimul. 2012 Jul;5(3):201-207. doi: 10.1016/j.brs.2011.04.002. Epub 2011 May 5.
citation: Younger JW, Randazzo Wagner M, Booth JR. Weighing the Cost and Benefit of Transcranial Direct Current Stimulation on Different Reading Subskills. Front Neurosci. 2016 Jun 7;10:262. doi: 10.3389/fnins.2016.00262. eCollection 2016.
citation: Younger JW, Booth JR. Parietotemporal Stimulation Affects Acquisition of Novel Grapheme-Phoneme Mappings in Adult Readers. Front Hum Neurosci. 2018 Mar 23;12:109. doi: 10.3389/fnhum.2018.00109. eCollection 2018.
citation: Heth I, Lavidor M. Improved reading measures in adults with dyslexia following transcranial direct current stimulation treatment. Neuropsychologia. 2015 Apr;70:107-13. doi: 10.1016/j.neuropsychologia.2015.02.022. Epub 2015 Feb 19.
citation: Costanzo F, Varuzza C, Rossi S, Sdoia S, Varvara P, Oliveri M, Koch G, Vicari S, Menghini D. Reading changes in children and adolescents with dyslexia after transcranial direct current stimulation. Neuroreport. 2016 Mar 23;27(5):295-300. doi: 10.1097/WNR.0000000000000536.
citation: Costanzo F, Varuzza C, Rossi S, Sdoia S, Varvara P, Oliveri M, Giacomo K, Vicari S, Menghini D. Evidence for reading improvement following tDCS treatment in children and adolescents with Dyslexia. Restor Neurol Neurosci. 2016;34(2):215-26. doi: 10.3233/RNN-150561.
citation: Costanzo F, Rossi S, Varuzza C, Varvara P, Vicari S, Menghini D. Long-lasting improvement following tDCS treatment combined with a training for reading in children and adolescents with dyslexia. Neuropsychologia. 2019 Jul;130:38-43. doi: 10.1016/j.neuropsychologia.2018.03.016. Epub 2018 Mar 14.
citation: Rios DM, Correia Rios M, Bandeira ID, Queiros Campbell F, de Carvalho Vaz D, Lucena R. Impact of Transcranial Direct Current Stimulation on Reading Skills of Children and Adolescents With Dyslexia. Child Neurol Open. 2018 Oct 4;5:2329048X18798255. doi: 10.1177/2329048X18798255. eCollection 2018.
citation: Lazzaro G, Costanzo F, Varuzza C, Rossi S, De Matteis ME, Vicari S, Menghini D. Individual differences modulate the effects of tDCS on reading in children and adolescents with dyslexia. Scientific Studies of Reading. 2021; 25(6): 1-17.
citation: Lazzaro G, Costanzo F, Varuzza C, Rossi S, Vicari S, Menghini D. Effects of a short, intensive, multi-session tDCS treatment in developmental dyslexia: Preliminary results of a sham-controlled randomized clinical trial. Prog Brain Res. 2021;264:191-210. doi: 10.1016/bs.pbr.2021.01.015.
citation: Battisti A, Lazzaro G, Costanzo F, Varuzza C, Rossi S, Vicari S, Menghini D. Effects of a short and intensive transcranial direct current stimulation treatment in children and adolescents with developmental dyslexia: A crossover clinical trial. Front Psychol. 2022 Sep 9;13:986242. doi: 10.3389/fpsyg.2022.986242. eCollection 2022.