Which part of the brain stores information for automatic word recognition?
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Many studies have looked at the parts of the brain that are activated in typical readers (and weak readers). Show Neuro-imaging methods have revealed three brain regions involved in reading that develop as children gain word-level reading skills (see Figure 1):
 Figure 1. Reading centres and pathways in the brain. With permission from Dr. Devin Kearns. 2019. Reading pathways in the brainThese three areas of the brain are involved in TWO reading pathways:
It is thought that beginner readers first use the dorsal pathway (decoding) when they are learning to read. In early reading stages, most words must be ‘decoded’, that is, the letters in the word must be linked to the sounds they represent. As words become familiar and stored in long term memory, they can be read more quickly through the ventral pathway; reading becomes much more automatic. At this stage, it is very difficult to look at a familiar word and not read it – the process is so automatic. Words that are read ‘automatically’ are often called ‘sight words’. Orthographic mappingThis process where a word’s spelling and meaning gets stored into permanent, long-term memory as a ‘sight word’ is termed “orthographic mapping”. Research has shown that orthographic mapping is enabled by phonological awareness and grapheme-phoneme knowledge (Ehri 2014; Yoncheva et al., 2015), and that instruction in letter-sound mapping also supports the self-teaching of unfamiliar but decodable words (Yoncheva et al., 2015). Read more about orthographic mapping on the Science of reading page. Dyslexia and the neurobiology of readingFunctional and structural differences have been found in parts of the brain used for reading in people with dyslexia compared to normal readers and these differences have been found prior to learning to read (Kearns et al., 2019, Norton et al, 2015; Ozernov-Palchik et al., 2016). Differences in connectivity efficiency between the areas of the brain in reading have also been reported ( Finn et al., 2014; Lou et al., 2018; Raschle et al., 2011; Saygin et al, 2013; Saygin et al., 2016; Tschentscher et al., 2019; Vandermosten et al., 2016, Zhou et al., 2015). For example, some people with dyslexia do not have the same activation in the brain in the same areas that are activated in good readers. Some people may have good activation in the dorsal pathway (they can decode accurately) but the ventral pathway is not efficient, and they struggle with automaticity. Dyslexia runs in families and several candidate genes for dyslexia susceptibility have been identified (Ozernov-Palchik et al., 2016). There is evidence from neurological research that reading (especially decoding) difficulties can often be remediated with appropriate reading instruction. Recently, studies have shown that effective remediation/instruction is associated with increased activation or normalization of regions that typically show reduced or absent activation in dyslexia (Barquero et al, 2014; Gabrieli, 2016). Finally, neuroimaging studies (along with many behavioural studies) support the use of foundational word-recognition instruction (Kearns et al., 2019) as provided by structured literacy instruction. References Expand Barquero, L.A., N. Davis, L.E. Cutting. 2014. Neuroimaging of reading intervention: a systematic review and activation likelihood estimate meta-analysis. PLoS ONE. 9(1):e83668. Ehri, L. 2014. Orthographic mapping in the acquisition of sight word reading, spelling memory, and vocabulary learning. Finn, E.S., et al. 2014. Disruption of functional networks in dyslexia: a whole-brain, data-driven analysis of connectivity. Biol. Psychiatry. 76:397-404. Gabrieli, J.D. 2009. Dyslexia: a new synergy between education and cognitive Kearns, D.M., Hancock, R., Hoeft, F., Pugh, K.R. and S.J. Frost. 2019. The neurobiology of dyslexia. Teaching Exceptional Children. 51 (3):175-188. Lou C., et al. 2018. White matter network connectivity deficits in developmental dyslexia. Human Brain Mapping. 40:505-516. Norton, E.S., S.D. Beach, J.D.E. Gabrieli. 2015. Neurobiology of dyslexia. Current Opinion in Neurobiology. 30:73-78. Ozernov-Palchik, O. et al. 2016. Lessons to be learned: how a comprehensive neurobiological framework of atypical reading development can inform educational practice. Current Opinion in Behavioral Sciences. 10: 45-58. Raschle, N.M., M. Chang, N. Gaab. Saygin, Z.M. et al. 2013. Tracking the roots of reading ability: white matter volume and integrity correlate with phonological awareness in prereading and early-reading Saygin, Z,M. et al. 2016. Connectivity precedes function in the development of the visual word form area. Nature Neuroscience. 19:1250-1266. Tschentscher, N., A. Ruisinger, H. Blank, B. Diaz, K. von Kriegstiein. 2019. Reduced structural connectivity between left auditory thalamus and the motion-sensitive planum temporale in developmental dyslexia. The Journal of Neuroscience. 39(9):1720-1732. Vandermosten, M., F. Hoeft & E.S. Norton. 2016. Integrating MRI brain imaging studies of pre-reading children with current theories of developmental dyslexia: a review and quantitative meta-analysis. Current Opinion in Behavioral Sciences. 10:155-161. What Works Clearinghouse. 2009. Assisting Students Struggling with Reading: Response to Intervention (RtI) and Multi-Tier Intervention in the Primary Grades. National Center for Education Evaluation and Regional Assistance, U.S. Department of Education. NCEE 2009-4045. Yoncheva, Y.N., J. Wise, B. McCandliss. 2015. Hemispheric specialization for visual words is shaped by attention to sublexical units during initial learning. Brain & Language. 145-146: 23-33. A summary is available here. Zhou w., et al. Altered connectivity of the dorsal and ventral visual regions in dyslexic children: a resting-state fMRI study. 2015. Frontiers in Human Neuroscience. 9: article 495. doi: 10.3389/fnhum.2015.00495. What part of the brain is active when reading?The frontal lobe handles speech production, reading fluency, grammatical usage, and comprehension, making it possible to understand simple and complex grammar in our native language.
What the brain does when it reads?When you read letters on a page, the left occipito-temporal cortex of your brain immediately links each written word to its spoken equivalent. One part of your brain analyzes the word's meaning, while another part makes it possible to automatically recognize words.
Where is the orthographic processor in the brain?Orthographic processing is believed to be located in the fusiform gyrus, an area that overlaps the temporal, parietal, and occipital lobes in the lower part of the cortex in both hemispheres. This is where letter sequences are stored and retrieved from.
What is the 4 part processor?The Four-Part Processing Model for word recognition is a simplified model that illustrates how the brain reads or recognizes words. It illustrates that there are four processes that are active in the reading brain including: phonological, orthographic, meaning, and context processors (Moats & Tolman, 2019).
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