Possible disrupted biological movement processing in Developmental Coordination Disorder

EEG spectral power in developmental coordination disorder and attention-deficit/hyperactivity disorder: a pilot study

Developmental coordination disorder (DCD) and attention-deficit/hyperactivity disorder (ADHD) overlap in symptoms and often co-occur. Differentiation of DCD and ADHD is crucial for a better understanding of the conditions and targeted support. Measuring electrical brain activity with EEG may help to discern and better understand the conditions given that it can objectively capture changes and potential differences in brain activity related to externally measurable symptoms beneficial for targeted interventions. Therefore, a pilot study was conducted to exploratorily examine neurophysiological differences between adults with DCD and/or ADHD at rest. A total of N = 46 adults with DCD (n = 12), ADHD (n = 9), both DCD + ADHD (n = 8), or typical development (n = 17) completed 2 min of rest with eyes-closed and eyes-open while their EEG was recorded. Spectral power was calculated for frequency bands: delta (0.5-3 Hz), theta (3.5-7 Hz), alpha (7.5-12.5 Hz), beta (13-25 Hz), mu (8-13 Hz), gamma (low: 30-40 Hz; high: 40-50 Hz). Within-participants, spectral power in a majority of waveforms significantly increased from eyes-open to eyes-closed conditions. Groups differed significantly in occipital beta power during the eyes-open condition, driven by the DCD versus typically developing group comparison. However, other group comparisons reached only marginal significance, including whole brain alpha and mu power with eyes-open, and frontal beta and occipital high gamma power during eyes-closed. While no strong markers could be determined to differentiate DCD versus ADHD, we theorize that several patterns in beta activity were indicative of potential motor maintenance differences in DCD at rest. Therefore, larger studies comparing EEG spectral power may be useful to identify neurological mechanisms of DCD and continued differentiation of DCD and ADHD.

Exploring the presence and impact of sensory differences in children with Developmental Coordination Disorder

BACKGROUND

Children with Developmental Coordination Disorder (DCD) can experience sensory differences. There has been limited exploration of these differences and their impact on children with DCD.

AIMS

i) To explore the presence and impact of sensory differences in children with DCD compared to children without DCD; ii) To examine whether sensory differences are related to motor ability, attention deficit hyperactivity disorder (ADHD), or autistic traits.

METHOD

Parents of children (8-12 years) with (n = 23) and without (n = 33) DCD used standardised questionnaires to report on their children's sensory differences, autistic traits, and ADHD traits. Motor abilities were assessed through the Movement Assessment Battery for Children-2. Data were explored both categorically (between-groups) and dimensionally.

RESULTS

Children with DCD had significantly higher levels of sensory differences than children without DCD. Sensory differences also had a significantly greater impact on daily activities for children with DCD. Higher levels of ADHD and autistic traits, but not motor ability, were significant independent predictors of higher levels of sensory difference.

CONCLUSION

Children with DCD experience high levels of sensory differences, which impact on their daily lives. These sensory differences may be a marker for additional neurodivergence in children with DCD. Practitioners should consider the sensory needs of children with DCD.

WHAT THIS PAPER ADDS

This paper provides insight into the sensory features of children with DCD and the impact that sensory differences can have on daily living. Using parent-report, we found that children with DCD had increased sensory differences relative to children without DCD. These included increased hyperresponsiveness, increased hyporesponsiveness, and increased sensory interests, repetitions, and seeking behaviours (SIRS). We also found that sensory differences had a greater impact on daily living for children with DCD compared to children without DCD. Across the whole sample, autistic traits predicted hyperresponsivity and hyporesponsivity patterns; whereas traits of hyperactivity and impulsivity predicted SIRS. Motor abilities did not uniquely predict sensory differences, suggesting that other traits of neurodivergence may contribute to the sensory differences in DCD. Taken together, these findings highlight the necessity of considering sensory needs when supporting children with DCD. They also suggest that if sensory differences are identified in children with DCD, it may be due to the presence of co-occurring neurodivergent traits or conditions.