Down syndrome (DS) is a common genetic developmental disorder characterized by the trisomy of chromosome 21 (Hsa21). All individuals with DS have some kind of intellectual disability, associated with dysfunction in cognition-related structures, including the frontal cortex. Studies have examined developmental changes in the frontal cortex during prenatal stages in DS, however little is known about cortical lamination and neuronal differentiation in postnatal periods in this neurodevelopmental disorder. Therefore, we examined the quantitative and qualitative distribution of neuronal profiles containing the neuronal migration protein doublecortin (DCX), the non-phosphorylated high-molecular-weight neurofilament SMI-32, the calcium-binding proteins calbindin D-28K (Calb), calretinin (Calr), and parvalbumin (Parv), as well as human β-amyloid and APP (6E10), Aβ1-42, and phospho-tau (CP-13) in the supragranular (SG, II/III) and infragranular (IG, V/VI) layers in the DS postnatal frontal cortex compared to neurotypically developing (NTD) controls from ages 28 weeks to 196.4 weeks using immunohistochemistry. Furthermore, cortical lamination was evaluated using thionin, a Nissl stain. We found DCX-immunoreactive (-ir) cells in both the SG and IG layers in younger cases, but not in the oldest cases in both groups. Strong expression of SMI-32 immunoreactivity was observed in pyramidal cells in layers III and V in the oldest cases in both groups, however SMI-32-ir cells appeared much earlier in NTD compared to DS. We found small and fusiform Calb-ir cells in the younger cases (28 to 44 weeks), while in the oldest cases, Calb immunoreactivity was also found in pyramidal cells. Calr-ir cells appeared earlier in DS at 32 weeks compared to NTD at 44 weeks, however both groups showed large bipolar fusiform-shaped Calr-ir cells in the oldest cases. Diffuse APP/Aβ-ir plaque-like accumulations were found in the frontal cortex grey and white matter at all ages, but no Aβ1-42 immunoreactivity was detected in any case. Furthermore, neuropil (but not cellular) granular CP-13 immunostaining was seen in layer I only at 41 weeks NTD and 33 weeks DS. Cell counts show a significantly higher cell number in SG compared to IG for all the neuronal markers in both groups, except in Calb and SMI-32. In NTD, age and brain weight showed the strongest correlations with all cellular counts, except in thionin where DS had a stronger negative correlation with age and brain weight compared to NTD. In addition, height and body weight showed a strong negative correlation in NTD with the migration and neurogenesis marker DCX. These findings suggest that trisomy 21 affects the postnatal frontal cortex lamination, neuronal migration<br/>eurogenesis, and differentiation of projection pyramidal cells and interneurons, which contribute to the disruption of the local and projection inhibitory and excitatory circuitries that may underlie the cognitive disabilities in DS.

The purpose of this study was to examine the validity of a modified Assisted Cycling Therapy bicycle for improving depression in children with Down Syndrome (DS). Seven participants completed 2x/week for 8 weeks, 30 minutes at a time of ACT, in which participants’ voluntary pedaling rates were augmented via the bicycle motor, ensuring that they were pedaling at a rate greater than their self-paced rate. Depression was measured using a modified version of the Children’s Depressive Inventory, called the CDI-2. Our study demonstrated that the scores from the CDI-2 decreased, demonstrating less depressive symptomatology after the conclusion of the 8 week intervention. Our results were interpreted via our model of the mechanisms involved in influencing the success of ACT. Future research would include a greater sample size, a more relevant measure of depressive scores, and a consistent data collection environment. However our initial pilot study showed promising results for improving mental health in children with DS.

The primary goal of this study is to assess and develop an understanding of the effects of Assisted Cycling Therapy on manual motor performance in children with Down syndrome. Seven children (Mage 11.6 years old) completed a 30-minute cycle session 2x/week for 8 weeks on the PACT bicycle at a 35% greater rate than their self-selected rate. Pre- and post-testing of grip force with a dynamometer and unimanual and bimanual manual dexterity using the Purdue Pegboard were measured to determine changes in force production and fine motor control, respectively. Results consistently showed improvements in grip force in both hands and bimanual dexterity following PACT. My results are interpreted with respect to cerebral lateralization and neuroplasticity following PACT intervention.

Research has shown the benefits of exercise on people with (DS), and how it affects their quality of life (Maïano et al. 2019). However, many studies have also shown that the majority of people with DS do not meet the national minimum requirements for physical activity per day (Phillips et al. 2011). The current study will focus on Pediatric Assisted Cycle Therapy (PACT) as exercise and specifically its effects on children with DS. The goal is to improve the general behavioral skills of children with DS, which in turn can improve their quality of life. We predict that, based on pilot data (Gomez, 2015; Parker, 2016), GLTEQ will increase their total activity score following 8 weeks of PACT in young children with DS. The Godin Leisure Time Exercise Questionnaire was used to measure the participants’ participation levels in leisure time activity. Participants were involved in an 8-week intervention, in which they biked (PACT) for 30 minutes, twice a week. GLETQ was measured pre and post intervention and assessed using the scale provided by the GLETQ. The data from this study has shown a positive correlation between Leisure Time Activity and PACT. Overall, a mean increase in raw activity score in the GLETQ was shown.

Down syndrome (DS) is caused by either an extra copy of chromosome 21 or by extra material on chromosome 21. This causes various levels of intellectual disability and issues with gross motor skill development which can prevent these individuals from participating in activities of daily living (ADL) such as getting dressed, self-care, or grocery shopping. People with DS have a decreased ability to balance, an abnormal and slower gait pattern, difficulty adapting to new environments, and a lack of improvement in these areas with growth and development when compared to their neurotypical peers. The objective of this study was to determine the immediate effects of resistance training (RT) and assisted cycle therapy (ACT) on adults with DS’s balance ability and gait speed. Each participant completed one session of RT, ACT (stationary cycling with the assistance of a motor to maintain a cadence of at least 35% greater than their voluntary cycling speed), and no training in a randomly selected order. Balance and gait speed were measured by a Clinical Test of Sensory Interaction on Balance (CTSIB) (i.e., eyes open firm surface, eyes closed firm surface, eyes open foam surface, eyes closed foam surface) on a Balance Tracking System Board (Btracks board) and by a Timed Up and Go (TUG) test. A total of ten participants’ data was used for analysis. The measures of total path length (cm), anterior-posterior (AP) excursion, and medial-lateral (ML) excursion were used to analyze the CTSIB. The average time was used to analyze the TUG test. The results showed that the eyes closed foam surface balance task was the most challenging balance task for every participant in every intervention. Furthermore, the most improvement was evident in the eyes closed foam surface balance task from pre to post intervention in all of the interventions. Post hoc tests also indicated statistically significant improvements of path length from pre to post in the RT intervention with the eyes closed foam surface balance task as well as with AP excursion in the ACT intervention with the eyes closed foam surface balance task. Possible explanations for improvements from pre to post in the eyes closed foam balance task across all interventions will be discussed with respect to the length of the intervention, and the effect of strength, social and learned factors on balance in adults with DS.