Amazing Research Findings from the Last 10 Years
There’s been a lot of really interesting research about Irlen Syndrome and the use of color as an intervention conducted over the last ten years. Here are some amazing research findings you might not know about that have been reported in scientific journals around the world. These studies use objective measures such as brain imaging and eye-tracking to assess improvements in brain function, performance, and symptom reduction, and they discuss the implications of Irlen symptoms among varying populations, such as those with fibromyalgia, traumatic brain injury, and Autism.
Note. Irlen Syndrome is also referred to as Meares-Irlen Syndrome, Scotopic Sensitivity Syndrome, and Visual Stress in the literature.
2022: Suppressing visual cortical activity might benefit people with CRPS or fibromyalgia.
Complex regional pain syndrome (CRPS) and fibromyalgia are chronic pain conditions associated with changes in the central nervous system, possibly leading to enhanced visual sensitivity. Researchers examined visual sensitivity elicited by different stimuli and in daily life, through an online study of people with CRPS (n = 57), fibromyalgia (n = 74), other pain (n = 50), and no pain (n = 89). Respondents rated changes in pain, discomfort, or distress from viewing patterns with different spatial frequencies (lower-order visual processing), and reversible figures (bistable images; higher-order visual processing). Respondents with CRPS or fibromyalgia reported more visual discomfort than pain-related and pain-free controls while viewing striped patterns and a circle, with no effect of spatial frequency. They reported more pain while viewing a nonreversible square, but not reversible figures (Necker Cube, Duck/Rabbit). Finally, they reported more daily visual sensitivity than pain-related and pain-free controls. (Ten Brink, A. F., & Bultitude, J. H. (2022). Visual Sensitivity in Complex Regional Pain Syndrome and Fibromyalgia: An Online Study. Perception, 51(3), 187-209.)
2022: Patients recovering from traumatic brain injury subjectively report that precision tinted lenses improve their post-traumatic light sensitivity and migraines.
In a review of research regarding the use of colored filters among patients recovering from traumatic brain injuries, researchers found that while there is a paucity of information related to the therapeutic use of tinted lenses to mitigate post-traumatic light sensitivity and migraines, patients subjectively report improved symptoms, specifically with precision tints or FL-41. (Bansal, S., & Green, K. (2022). Application of colored filters in patients post-traumatic brain injury: A review. NeuroRehabilitation, (Preprint), 1-10.)
2020: Eye-tracking data shows objective improvements in reading with colored overlays.
(reduced the number of Fixations and Regressions and improved Span of Recognition, Reading Rate, Relative Efficiency, and Comprehension. Spectral overlays immediately and significantly (p < .001) reduced the number of Fixations and Regressions per 100 words, while there were significant (p < .001) gains in positive factors such as Span of Recognition, Reading Rate, Relative Efficiency, and Comprehension. (Guimarães, M. R., Vilhena, D. D. A., Loew, S. J., & Guimarães, R. Q. (2020). Spectral overlays for reading difficulties: oculomotor function and reading efficiency among children and adolescents with visual stress. Perceptual and Motor Skills, 127(2), 490-509.)
2020: Tinted lenses improve social cognition in children with Autism Spectrum Disorders.
A masked randomized control design compared the effectiveness of precision ophthalmic tints in improving the recognition of emotion in Autism Spectrum Disorders (ASD). Performance in the ASD group was superior in both social interaction tasks with the lenses that provided the optimal colour of light. (Ludlow, A. K., Giannadou, A., Franklin, A., Allen, P. M., Simmons, D. R., & Wilkins, A. J. (2020). The possible use of precision tinted lenses to improve social cognition in children with Autism Spectrum Disorders. Vision Research, 170, 53-59.)
2020: Spectral filters reduce TBI-related migraines and visual cortical sensitivity.
Pre versus post comparison of migraine frequency, medication usage, and scores on the HIT-6TM showed that there was a significant reduction in migraine frequency (M=18.8, SD=22.0 vs. M=2.0, SD=6.0); t(181) = 10.6, p=.000. There was also significant improvement (M=66.0, SD=8.0 vs. M=41.6, SD=9.9) in terms of impact of headaches on functional health and well-being, t(183) = 32.9, p=.000. fMRI retinotopic scans show precision-tinted spectral versus blank filters reduced within primary and secondary visual regions as well as fronto-parietal attentional networks, consistent with reduced hyperactivity to visual stimulation and reduced recruitment of neural networks outside of the visual system proper. Preliminary evidence supports reduced uncontrolled cortical excitability to patterned light stimulation as a potential mechanism of action. (Anderson, A., De Rosa, E., & Tosta, S. (2020, March). Precision-Tinted Spectral Filters Reduce TBI-Related Migraines and Visual Cortical Sensitivity. In JOURNAL OF HEAD TRAUMA REHABILITATION (Vol. 35, No. 2, pp. E199-E200). TWO COMMERCE SQ, 2001 MARKET ST, PHILADELPHIA, PA 19103 USA: LIPPINCOTT WILLIAMS & WILKINS.)
2019: Systematic review and meta-analysis shows improved reading performance using colored overlays.
63% of children in the general population inform perceptual improvement in text clarity with the use of overlays. The prevalence with the sustained use of at least two months is revealed in 30% of the general population. Finally, under the use of overlays, 33% of the population improved reading speed, quantified via Rate of Reading Test, with 18% presenting moderate to robust gains. The clinical groups that are most likely to gain reading speed with the use of overlays are, respectively: Tourette Syndrome, Multiple Sclerosis, Autistic Spectrum Disorder, Reading Difficulty. (de Araújo Vilhena, D., Guimarães, MR, & Guimarães, RQ (2019). Improved reading performance using spectral slides: systematic review and meta-analysis. Psychology Argument, 36(93), 343-361.)
2019: About one-third of those diagnosed with dyslexia also have Irlen Syndrome.
A study of a sample of adults with dyslexia found that 27% also had Irlen Syndrome. (Caskey, J., & Freney, P. (2019). IS THERE A RELATIONSHIP BETWEEN DYSLEXIA AND MEARES IRLEN-SYNDROME IN ADULT VOCATIONAL STUDENTS? European Journal of Education Studies.)
2018: Colored overlays result in increased reading speed, especially for those with discomfort.
13% of the children presented an improvement of at least 15% in reading speed with the use of spectral overlays. Pupils with severe reading difficulties tended to have more improvement in RRT with spectral overlays. Children with severe reading discomfort obtained the highest gains in RRT. Overlays can improve reading performance, particularly in those children with severe visual discomfort. (Garcia A.C.O., Momensohn-Santos T.M., Vilhena D.A. (2018). Effects of Spectral Overlays on Reading Performance of Brazilian Elementary School Children, Folia Phoniatr Logop, 69, 219-225.)
2018: There is evidence of a genetic, biochemical and immunological bases of Meares-Irlen syndrome.
An integrative literature review aimed to analyze the scientific production in relation to biochemical, genetic and immunological basis that maybe understood in this condition. Many studies have suggested an association of the syndrome with biochemical and genetic alterations. Some support the hypothesis that immune changes and metabolism of fatty acids are involved in cognitive and learning problems. Despite the scarce volume of studies on the subject, there is increasing evidence that there is a biochemical basis involved in a variety of visual disorders and learning. (Soares, F. A., & Gontijo, L. S. (2016). Production of knowledge: genetic basis, biochemical and immunological of Meares-Irlen Syndrome. Revista Brasileira de Oftalmologia, 75, 412-415.)
2017: Colored glasses significantly improve attention performance according to electrophysiological late event-related potential patterns.
The present investigation examined whether changes of electrophysiological late event related potential pattern could be used to reflect clinical changes from therapeutic intervention with coloured glasses in a group of patients with symptoms of central visual processing disorder. Subjects consisted of 13 patients with average age 16 years (range 6–51 years) with attention problems and learning disability, respectively. These patients were provided with specified coloured glasses which were required to be used during day time. Results indicated that specified coloured glasses significantly improved attention performance. Furthermore electrophysiological parameters revealed a significant change in the late event-related potential distribution pattern (latency, amplitudes). This reflects a synchronization of together firing wired neural assemblies responsible for visual processing, suggesting an accelerated neuromaturation process when using coloured glasses. Visual event-related potentials measures are sensitive to changes in clinical development of patients with deficits of visual processing wearing appropriate coloured glasses. (Friederichs, E., & Wahl, S. (2017). (Re)-wiring a brain with light: Clinical and visual processing findings after application of specific coloured glasses in patients with symptoms of a visual processing disorder (CVPD): Challenge of a possible new perspective? Medical hypotheses, 105, 49-62.)
2016: Tinted filters result in increased visual comfort for adults with mTBI reporting photosensitivity and reading problems.
The aim of the present pilot study was to determine the effect of spectral filters on reading performance and visuo-cortical responsivity in adults with mTBI. While there were few significant group differences in either the reading-related parameters or VEP latency for any of the test filter conditions, subjective improvements were noted in most with mTBI (11/12), supporting improved visual comfort. While significant findings based on the objective testing were found for some conditions, the subjective results suggest that precision tints should be considered as an adjunctive treatment in patients with mTBI and photosensitivity. (Fimreite, V., Willeford, K. T., & Ciuffreda, K. J. (2016). Effect of chromatic filters on visual performance in individuals with mild traumatic brain injury (mTBI): a pilot study. Journal of Optometry, 9(4), 231-239.)
2015: fMRI data shows improved brain function with colored filters that correlates directly with improved reading measures.
The reading speed of patients improved by more than 20% while wearing the selected lenses. When compared to the before-lens session, the after-lens session identified significant regions of activation in the left middle and superior temporal gyri (paired t-test; maximal z score, 38; Montreal Neurological Institute coordinate, -60 / -39 / 0; threshold at p < 0.05; corrected for multiple comparisons using family-wise error). No region of activation at the same threshold was found in the before-lens session as compared to the after-lens session. Conclusions: In the current study, we confirmed activation in the left middle and superior temporal gyri during sentence reading after wearing color-tinted lenses. (Kim, J. H., Seo, H. J., Ha, S. G., & Kim, S. H. (2015). Functional Magnetic Resonance Imaging Findings in Meares-Irlen Syndrome: A Pilot Study. Korean Journal of Ophthalmology, 29(2), 121-125.)
2012: There is brain imaging evidence of a neurobiological foundation of Irlen Syndrome.
There are significant differences in the amount of activation in both the visual cortex (primary and extrastriate) and the somatosensory cortex (postcentral gyrus) – the area of the brain that interprets information on touch, temperature, pain, and pressure between individuals with Irlen Syndrome and controls. (Chouinard, B. D., Zhou, C. I., Hrybouski, S., Kim, E. S., & Cummine, J. (2012). A functional neuroimaging case study of Meares–Irlen syndrome/visual stress (MISViS). Brain topography, 25(3), 293-307.)
2012: Colored filters are effective for alleviating visual symptoms and improving reading speed.
Twenty-five patients were selected through a brief questionnaire aimed to determine symptoms of eyestrain or visual distortion after thorough eye examinations. Two months after wearing the individually prescribed colored filters, a questionnaire on the patient’s subjective satisfaction with the colored filters were completed and evaluated. The mean reading rate improved from 82.72 wpm (words per minute) to 101.84 wpm with the colored filters, a statistically significant change (p = 0.019). The overall satisfaction score with the colored lenses was 3.6, with the highest score given to ease of reading (4.08). (Park, S. H., Kim, S. H., Cho, Y. A., & Joo, C. K. (2012). The effect of colored filters in patients with Meares-Irlen syndrome. Journal of the Korean Ophthalmological Society, 53(3), 452-459.)
2011: Precision-tinted filters normalize hyperactivity in the visual cortex related to migraine (V2-V4).
fMRI identified normalization of cortical activation (V2-V4) and spatial frequency tuning (V2) in the migraineurs by precision tinted filters that suggests a neurological basis for the therapeutic effect of these lenses in reducing visual cortical hyperactivation in migraine. (Huang, J., Zong, X., Wilkins, A., Jenkins, B., Bozoki, A., Cao, Y. (2011). fMRI evidence that precision ophthalmic tints reduce cortical hyperactivation in migraine. Cephalagia, 31(8):925-36.)