Fragile X syndrome (FXS) is an inherited genetic disorder resulting in developmental delays and challenging behaviors. Reliable, accurate tests are available for carrier, prenatal, or newborn screening. Since genetic screening is not routinely offered, FXS is typically identified through behavioral observation. The variability and subtlety in the expression of FXS make early identification challenging. The article reviews the research and recommends a set of characteristics to enhance the identification process. While a checklist alone is unlikely to improve identification during the infant-toddler years, it may alert professionals to more obvious cases, help confirm parental and professional suspicions over several visits, and yield more fine-grained observations and precise comparisons.
Introduccion: La tecnica de demora constante es una practica basada en la evidencia que ensena a reconocer en vista palabras de uso frecuente a estudiantes con multidiscapacidad. Hasta la fecha, existen dos estudios que han documentado su eficacia en la ensenanza de braille. Metodologia: A traves de un diseno de linea base multiple hemos evaluado la eficacia de la tecnica de demora constante en la ensenanza de palabras muy motivadoras a tres lectores de braille principiantes con discapacidad del desarrollo. Entre las variaciones procedimentales se encuentran una herramienta para la pre-ensenanza y la evaluacion, un criterio superior para el dominio de la actividad, un mayor numero de ensayos por sesion y una retroalimentacion correctiva por parte del profesor. Resultados: Se establecio una relacion funcional para los tres participantes. Los alumnos dominaron la tecnica en un periodo de cuatro a doce sesiones de menos de una hora de duracion. Aunque el numero de respuestas correctas disminuyo con el tiempo, la retencion a largo plazo quedo demostrada. Discusion: Los resultados muestran que se trata de una tecnica muy prometedora para ensenar a lectores de braille en edades tempranas, si bien se requieren posteriores replicas de este estudio para establecer la tecnica de demora constante como una practica basada en la evidencia para alfabetizar a lectores de braille. Aspectos de aplicacion en la atencion practica: Se recomienda a los profesionales que adopten esta tecnica en el contexto de los programas generales de lectoescritura, con el objetivo de generalizar la lectura de todo tipo de palabras.
The association made between the meaning, spelling, and pronunciation of a word has been shown to help children remember the meanings of words. The present study addressed whether the presence of a target word in Braille during instruction facilitated vocabulary learning more efficiently than an auditory-only instructional condition. The authors used an adapted alternating treatments single-case experimental design with three students with visual impairments who read Braille, collecting data on definition recall and spelling during each session. Data on definition recall were used to determine mastery. The results of this study are not consistent with previous findings with students who read print. Visual analyses of the data indicated that participants reached mastery in both conditions, but all three reached mastery on definition recall in fewer sessions in the auditory-only condition. Spellings of words were learned in the flashcard condition only, and possible implications of this are discussed. The difference in the unit of recognition and working memory load between reading Braille and reading print is discussed as one possible explanation.
The performance of 54 boys with fragile X syndrome (FXS), ages 7 to 13 years, was compared to that of a group of typically developing boys who were matched on mental age (MA) and ethnicity across multiple measures of executive function (EF). Boys with FXS varied in their ability to complete EF measures, with only 25.9% being able to complete a set-shifting task and 94.4% being able to complete a memory for word span task. When compared to the control group, and controlling for MA and maternal education, boys with FXS showed significant deficits in inhibition, working memory, cognitive flexibility/set-shifting, and planning. No group differences were observed in processing speed. Mental age significantly impacted performance on working memory, set-shifting, planning, and processing speed tasks for both groups. In boys with FXS, MA significantly predicted performance on working memory and set-shifting tasks. Our findings suggest that deficits in EF in boys with FXS are not solely attributable to developmental delays but, rather, present as a true array of neurocognitive deficits.
The academic achievement of boys with fragile X syndrome and the relation between several predictive factors and academic performance are reported. Boys with fragile X syndrome displayed significant deficits in all academic skill areas. Relative strengths were observed in general knowledge, reflecting the ability to integrate experiential information. In contrast, relative weaknesses were observed in prewriting skills and visuospatial-processing abilities. The rate of academic growth slowed over time, and the decrease in rate was more pronounced in measures of core academic skills (e.g., prereading and math skills) than in broad-based tasks. Nonverbal IQ and FMR protein expression were not associated with the level or rate of change; however, autistic behavior and maternal education were related to academic achievement scores.
Effortful control, or the ability to suppress a dominant response to perform a subdominant response, is an early-emerging temperament trait that is linked with positive social-emotional development. Fragile X syndrome (FXS) is a single-gene disorder characterized by hallmark regulatory impairments, suggesting diminished effortful control. This study compared the development of effortful control in preschool boys with FXS ( n = 97) and typical development ( n = 32). Unlike their typical peers, the boys with FXS did not exhibit growth in effortful control over time, which could not be accounted for by adaptive impairments, FMR1 molecular measures, or autism symptoms. These results contribute to our understanding of the childhood phenotype of FXS that may be linked to the poor social-emotional outcomes seen in this group.
