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Anneli Veispak, Perceptual and Cognitive Underpinnings of Braille Reading.</></> Dissertation submitted to obtain the degree of Doctor in Educational Sciences 2012. Supervision: Prof. Dr. Pol Ghesquière, Dr. Bart Boets</>
Learning to read is a complex task requiring the translation of written symbols, or graphemes, into speech forms, or phonemes. Given that the brain evolved to understand communicative messages conveyed by speech, the pre-existing neural circuitries for spoken language and object recognition have had to adapt to the explicit needs of reading. Reading acquisition is therefore less trivial than it looks. Even though the majority of children will master the reading skill fluently and well,about 5-10% of the population develops a specific reading impairment i.e. developmental dyslexia, which is a neurological disorder resulting ina failure to acquire reading and spelling skills despite adequate intelligence, instruction and remedial efforts. Similarly to the sighted population, a proportion of blind children have specific difficulties related to reading braille, which cannot be easily explained. Very few studieshave been conducted to investigate the cognitive and perceptual abilities which are relevant for fluent braille reading and which might be affected in the case of braille reading difficulties. Since braille and print are linguistically identical, the findings from print reading researchcan be used for testing hypothesis about reading braille. Hence in our research, being inspired by the concepts of the phonological and the temporal processing deficit theories of developmental dyslexia, we have combined auditory, speech and phonological processing as well as tactile spatial resolution measures to gain an understanding of how these perceptual and cognitive processes interact in support of reading braille as opposed to reading print.</>
The participants of the current project were blind braille readers from Belgium (n=12), the Netherlands (n=16) and Estonia (n=12). Thirty-three of the included braille readers were blind from birth, while 7 had lost their vision before the age of 10. Twenty one braille readers are able to perceive light, whereas nineteen have no remaining rest vision. Based on age, sex, nationality and educational level a matched control group of sighted print readers was composed. All participating braille and print readers had normal intelligence as well as hearing and they spoke Dutch and Estonian as their first language respectively. In order to observe possible developmental patterns, the Dutchspeaking participants were also divided into groups based on age: a group of young readers (younger than 16 years of age) and a group of adult readers (older than 16 years of age).</>
Differently from visual processing, which enables simultaneous and parallel perception of text, the tactile modality offers a successive input and imposes a sequential nature of reading. Since fingers must necessarily pass over all the characters on a line, braille reading is believed to mirror the grapho-phonological reading strategy (character-by-character) which is prominent in young and inexperienced print readers. While sighted readers apply a direct orthographic route to read frequent or irregular words and </>the indirect grapho-phonological route to decode infrequent and unfamiliar words or nonwords, braille readers, we hypothesized, should use the same grapho-phonological route indiscriminately. Therefore, we administered word reading, pseudoword reading and story reading tests, measuring accuracy and speed of reading in all conditions. If blind readers are inclined to constant decoding, an effective engagement of various phonological processing skills should be required throughout the reading process. In order to assess these phonological processing abilities we administered phonological awareness tests (phoneme deletion and spoonerism), verbal short term memory tests (digit span and nonword repetition) and tests measuring lexical retrieval speed, i.e. rapid automatic naming (RAN digits and RAN letters). Auditory temporal processing has been suggested to have a crucial impact on the development of adequate phonological representations through speech perception. Thus far, no studies have investigatedthe relation between auditory processing and braille reading. Considering the postulated association between auditory processing, speech perception and the quality of phonological representations and given the hypothetical role of phonological processing in braille reading, we administered both auditory temporal processing as well as speech perception tasks. A</>uditory temporal processing was assessed with a frequency modulation detection test and </>speech perception was measured by the words-in-noise and sentences-in-noise perception tests. A specific aspect pertaining to braille reading is tactile spatial acuity, which plays an essential part in the correct identification of the relative spatial position of the dots in braille characters. In order to measure tactile spatial acuity in the current study, a grating orientation task was administered.</>
The results revealed that the sequential nature of braille does impose constant decoding and effective recruitment of phonological skills throughout the reading process. In addition to the significant item length effect (i.e. reading times increase with the number of constituent syllables of the word) on both word and pseudoword reading speed, phonological awareness and verbal short-term memory correlated substantially with all the reading accuracy measures in both Dutch and Estonian groups ofbraille readers. In the group of print readers, on the other hand item length effect was only observable on pseudoword reading measures, which in turn also correlated with phonological awareness. Hence, it can be suggested that sighted print readers switch between the use of grapho-phonological and orthographic processing modes depending on the familiarity,length and structure of the words. While braille readers performed equally well as print readers on speech perception tests, they did present slightly better thresholds (though non-significant) on the auditory frequency modulation detection task. Furthermore, both frequency modulation detection and speech perception not only correlated with phonological processing measures in the group of braille readers, but also related directly to braille reading performance. In the group of print readers, conversely, no direct associations between reading performance and auditory as well as speech processing were observed. Tactile spatial acuity correlated significantly with both braille reading accuracy as well as speed. To conclude, it can be suggested that highly developed phonological awareness and verbal short-term memory skills, corroborated by auditory processing and speech perception aptitude, together with adequate tactile spatial acuity determine the level of braille reading achievement.</>
Project
Severe reading problems in blind children. Similarities with developmental dyslexia?
Anneli Veispak, Perceptual and Cognitive Underpinnings of Braille Reading.</></> Dissertation submitted to obtain the degree of Doctor in Educational Sciences 2012. Supervision: Prof. Dr. Pol Ghesquière, Dr. Bart Boets</>
Learning to read is a complex task requiring the translation of written symbols, or graphemes, into speech forms, or phonemes. Given that the brain evolved to understand communicative messages conveyed by speech, the pre-existing neural circuitries for spoken language and object recognition have had to adapt to the explicit needs of reading. Reading acquisition is therefore less trivial than it looks. Even though the majority of children will master the reading skill fluently and well,about 5-10% of the population develops a specific reading impairment i.e. developmental dyslexia, which is a neurological disorder resulting ina failure to acquire reading and spelling skills despite adequate intelligence, instruction and remedial efforts. Similarly to the sighted population, a proportion of blind children have specific difficulties related to reading braille, which cannot be easily explained. Very few studieshave been conducted to investigate the cognitive and perceptual abilities which are relevant for fluent braille reading and which might be affected in the case of braille reading difficulties. Since braille and print are linguistically identical, the findings from print reading researchcan be used for testing hypothesis about reading braille. Hence in our research, being inspired by the concepts of the phonological and the temporal processing deficit theories of developmental dyslexia, we have combined auditory, speech and phonological processing as well as tactile spatial resolution measures to gain an understanding of how these perceptual and cognitive processes interact in support of reading braille as opposed to reading print.</>
The participants of the current project were blind braille readers from Belgium (n=12), the Netherlands (n=16) and Estonia (n=12). Thirty-three of the included braille readers were blind from birth, while 7 had lost their vision before the age of 10. Twenty one braille readers are able to perceive light, whereas nineteen have no remaining rest vision. Based on age, sex, nationality and educational level a matched control group of sighted print readers was composed. All participating braille and print readers had normal intelligence as well as hearing and they spoke Dutch and Estonian as their first language respectively. In order to observe possible developmental patterns, the Dutchspeaking participants were also divided into groups based on age: a group of young readers (younger than 16 years of age) and a group of adult readers (older than 16 years of age).</>
Differently from visual processing, which enables simultaneous and parallel perception of text, the tactile modality offers a successive input and imposes a sequential nature of reading. Since fingers must necessarily pass over all the characters on a line, braille reading is believed to mirror the grapho-phonological reading strategy (character-by-character) which is prominent in young and inexperienced print readers. While sighted readers apply a direct orthographic route to read frequent or irregular words and </>the indirect grapho-phonological route to decode infrequent and unfamiliar words or nonwords, braille readers, we hypothesized, should use the same grapho-phonological route indiscriminately. Therefore, we administered word reading, pseudoword reading and story reading tests, measuring accuracy and speed of reading in all conditions. If blind readers are inclined to constant decoding, an effective engagement of various phonological processing skills should be required throughout the reading process. In order to assess these phonological processing abilities we administered phonological awareness tests (phoneme deletion and spoonerism), verbal short term memory tests (digit span and nonword repetition) and tests measuring lexical retrieval speed, i.e. rapid automatic naming (RAN digits and RAN letters). Auditory temporal processing has been suggested to have a crucial impact on the development of adequate phonological representations through speech perception. Thus far, no studies have investigatedthe relation between auditory processing and braille reading. Considering the postulated association between auditory processing, speech perception and the quality of phonological representations and given the hypothetical role of phonological processing in braille reading, we administered both auditory temporal processing as well as speech perception tasks. A</>uditory temporal processing was assessed with a frequency modulation detection test and </>speech perception was measured by the words-in-noise and sentences-in-noise perception tests. A specific aspect pertaining to braille reading is tactile spatial acuity, which plays an essential part in the correct identification of the relative spatial position of the dots in braille characters. In order to measure tactile spatial acuity in the current study, a grating orientation task was administered.</>
The results revealed that the sequential nature of braille does impose constant decoding and effective recruitment of phonological skills throughout the reading process. In addition to the significant item length effect (i.e. reading times increase with the number of constituent syllables of the word) on both word and pseudoword reading speed, phonological awareness and verbal short-term memory correlated substantially with all the reading accuracy measures in both Dutch and Estonian groups ofbraille readers. In the group of print readers, on the other hand item length effect was only observable on pseudoword reading measures, which in turn also correlated with phonological awareness. Hence, it can be suggested that sighted print readers switch between the use of grapho-phonological and orthographic processing modes depending on the familiarity,length and structure of the words. While braille readers performed equally well as print readers on speech perception tests, they did present slightly better thresholds (though non-significant) on the auditory frequency modulation detection task. Furthermore, both frequency modulation detection and speech perception not only correlated with phonological processing measures in the group of braille readers, but also related directly to braille reading performance. In the group of print readers, conversely, no direct associations between reading performance and auditory as well as speech processing were observed. Tactile spatial acuity correlated significantly with both braille reading accuracy as well as speed. To conclude, it can be suggested that highly developed phonological awareness and verbal short-term memory skills, corroborated by auditory processing and speech perception aptitude, together with adequate tactile spatial acuity determine the level of braille reading achievement.</>
Date:1 Oct 2008 → 30 Sep 2012
Keywords:Braille, Neuropsychology, Temporal processing, Dyslexia
Disciplines:Orthopedagogics and special education
Project type:PhD project