Here are some of the results from projects that have come out of the lab.
Numerical Skills in Young People with Down Syndrome
Researchers have begun to examine the most basic numerical skills in children with Down syndrome (DS). Non-symbolic numerical skills relate to judging quantities (e.g., more or less) without number symbols. Symbolic numerical skills relate to understanding number symbols and the quantities they stand for. For her master’s thesis, Kristina Baggett examined both types of numerical skills by comparing participants with DS (age 9 – 16 years old) and participants who are typically developing (TD) and are at the same vocabulary level (age 4 – 7 years old). This study was conducted over Zoom due to the pandemic. Participants completed a vocabulary test, a non-symbolic numerical skills test (judging which set of dots has more), and a symbolic numerical test (judging which number is more). Results showed that the children with DS performed similarly to the younger TD children. In other words, children with DS had numerical skills at the level that would be expected for their vocabulary level. They had no special difficulty with either type of numerical skill.
Wayfinding and Shortcuts
It is sometimes difficult to learn the layout of a place after moving through it just a few times, yet wayfinding is an important practical skill. It allows us to find new routes, take shortcuts, and orient when lost. Zach Himmelberger’s dissertation study sought to understand how wayfinding emerges over multiple exposures to a new environment. Three times, participants traveled through a virtual environment and then were asked to find a shortcut. Young adults with Down syndrome (DS), typically developing (TD) young adults, and typically developing children participated in the study. Results showed that participants DS were not as successful as TD young adults in finding a shortcut. Also, they did not improve as readily as TD children over repeated trials. Young adults with DS may need extra guidance and practice to learn wayfinding skills.
Modeling the Relationships Among Sustained Attention, Short-Term Memory, and Language in Down Syndrome
Language can be a challenge for youth with Down syndrome (DS). Gayle Faught’s dissertation study looked at the roles of sustained attention and short-term memory in language skills. Sustained attention is the ability to maintain attention over time and short-term memory is the temporary storage and retrieval of information in memory. Gayle looked at both auditory and visual sustained attention and short-term memory. Results suggested that participants with better language skills also had better auditory sustained attention and auditory short-term memory. Further, there seemed to be a directional relation, such that auditory sustained attention enabled auditory short term memory, which in turn related to better language skills. To foster language development in children with DS, parents and teachers can first ensure the child is attending, start with short sentences, and expand length and complexity gradually.
Measuring Physical Activity in Youth with Down Syndrome
Research has shown that physical activity results not only in health benefits but also in cognitive benefits. However, it is not always easy to measure physical activity. For his master’s thesis, Andrew Tungate examined two ways to measure physical activity in youth with Down syndrome (DS) – direct measurement and parent report. Youth with DS, ages 5-18 years old, wore a pedometer each day for a week to measure their number of steps; also, their parents completed a questionnaire on their son or daughter’s exercise habits. Andrew found that using a pedometer to measure daily physical activity worked well for teens with DS, but not so well for younger children with DS. He also found that, for those who did successfully use the pedometer, their average steps per day were below the level expected for their age. This suggests that youth with DS may need more daily physical activity. Finally, Andrew found that parent report needs more development, as it was challenging for parents to report the level of detail requested in the study questionnaires. We hope that what Andrew learned about measuring physical activity in youth with DS can be used in future research, because this is an important topic for health, cognition, and quality of life.
Reading Skills in Down Syndrome
Susan Loveall’s dissertation study examined various aspects of reading skills in individuals with Down syndrome (DS). Reading is a complex skill that is built off of many lower-level skills. The focus of this study was single word reading, or word recognition, which has two important subskills, one verbal and one visual. The verbal subskill is known as phonological decoding and is the ability to sound words out. The visual subskill is known as orthographic knowledge and is the ability to read words by recognizing common letter patterns. The study compared individuals with DS (age 11 to 21 years) to younger, typically developing (TD) children of the same word recognition reading level (age 5-9 years). Results showed that individuals with DS did not perform as well as the TD children on a measure of phonological decoding; however, they performed similarly to the TD children on two measures of orthographic knowledge. Thus, individuals with DS may be utilizing stronger visual skills when reading words. However, because it is so important to use phonological decoding to read new words, they may need extra emphasis on this subskill. Developing both verbal and visual word recognition skills could help individuals with DS attain higher levels of reading.
Home Literacy Environment of Individuals with Down Syndrome
The home literacy environment is defined as the number and type of literacy-related activities in the home, such as parent-child shared book reading, number of books in the home, number of trips to the library, and reading done by caregivers. Research shows that rich home literacy environments lead to better language development and reading achievement in typically developing children. As part of Susan Loveall’s dissertation, 56 parents of individuals with Down syndrome (DS) completed a reading questionnaire reporting on their child’s reading abilities, the home literacy environment, their child’s motivation to read, and their child’s language, vision and hearing. Of the parents with children with DS over the age of five, 95.9% reported that their child could read single words and 70.8% reported that their child could sound out new or unfamiliar words. Overall 73% of parents reported that they would describe their child as a reader. Almost all parents reported that they began reading to their child before their child was one year old. They also reported reading to their child regularly and always having children’s books in the home. Home literacy environment measures correlated with parent reports of the child’s motivation to read, as well as to vocabulary and word recognition in a subset of the sample who completed the study described above.
Parenting Children with Down Syndrome
A dissertation by Allyson Phillips examined parenting styles and dimensions in mothers of children with Down syndrome (DS) compared to mothers of typically developing (TD) children. While much work has been conducted on parenting typically developing children, little work has examined parenting children with DS. There are three primary parenting styles— authoritative, authoritarian, and permissive. Authoritative style considered best for healthy child development. Thirty-five mothers of children with DS and 47 mothers of typically developing children (age 5-12 years) completed a set of questionnaires asking about the way in which they parent their child, their child’s cognitive and behavioral abilities, their own well-being, and the expectations and fears they have in relation to their child. Overall, mothers of both types of children reported using authoritative parenting style most often; however, mothers of children with DS reported using authoritative parenting style less often than mothers of TD children. They also reported using a permissive parenting style more often than mothers of TD children. However, mothers of children with DS reported more parenting stress, and this accounted for the differences in parenting style. The results emphasize the role of parenting stress in choice of parenting style and highlight the importance of reducing parenting stress whenever possible.